Trifluoroethoxy-Coated Phthalocyanine Catalyzes Perfluoroalkylation of Alkenes under Visible ...

12 Pages·2017·0.87 MB·English

molecules
Article
Trifluoroethoxy-Coated Phthalocyanine Catalyzes
Perfluoroalkylation of Alkenes under
†
Visible-Light Irradiation
KoheiMatsuzaki1,TomoyaHiromura2,HidekiAmii3andNorioShibata1,2,*
1 DepartmentofNanopharmaceuticalSciences,NagoyaInstituteofTechnologyGokiso,Showa-ku,
Nagoya466-8555,Japan;[email protected]
2 DepartmentofLifeScienceandAppliedChemistry,NagoyaInstituteofTechnologyGokiso,Showa-ku,
Nagoya466-8555,Japan;[email protected]
3 DivisionofMolecularScience,GraduateSchoolofScienceandTechnology,GunmaUniversity,
1-5-1Tenjin-cho,Kiryu,Gunma376-8515,Japan;[email protected]
* Correspondence:[email protected];Tel./Fax:[phone]
† ThismanuscriptisdedicatedtothememoryofProfessorKenjiUneyama(1941–2017).
Received:19June2017;Accepted:3July2017;Published:7July2017
Abstract: Wedisclosehereintheperfluoroalkylationofalkenescatalyzedbytrifluoroethoxy-coated
zincphthalocyanineunderirradiationofvisiblelight.Perfluoroalkyliodideswerenicelyincorporated
into unsaturated substrates, including alkyne, to provide perfluoroalkyl and iodide adducts in
moderatetogoodyields. Trifluoromethylationisalsopossiblebytrifluoromethyliodideunderthe
samereactionconditions. Themechanisticstudyisdiscussed.
Keywords: phthalocyanine;photocatalysts;trifluoromethylation;perfluoroalkylation;visiblelight
1. Introduction
Perfluoroalkylgroupsfrequentlyappearedinthelibrariesofpharmaceuticals,agrochemicals,
and functional materials and in the methods for the introduction of perfluoroalkyl groups to
organic molecules, causing a massive accumulation of literature over the past few decades [1–5].
Radical perfluoroalkylation of alkenes using perfluoroalkyl halides (Rf-X) under shortwave UV
irradiationisoneoftheclassicalandwell-exploredmethodsforthispurpose[6–8]. However, the
classicalUVirradiationmethod[9–12]hasoftensufferedfromalackofselectivity,lowyields,and
complicatedreactiondevicessuchasthequartzvesselorthemerry-go-roundreactor. Inrecentyears,
radicalperfluoroalkylationhasdramaticallychangedforthesakeofdiscoveryofphotoredoxcatalyst
systemsundervisiblerightirradiation[13–31]. Themethodsdonotrequirecomplexreactiondevices
orharmfulUVirradiationbecauseenvironmentallybenignvisiblelightsandphotocatalystsareused
instead. Besides,highyieldsandhighchemoselectivitiesareoftenobservedunderphoto-catalysis
without any harsh reaction conditions. Photoredox catalysts containing ruthenium or iridium
complexedwithpolybipyridylligandsabsorbingbluelight(λ=375–450nm)aremainlyexplored
in this system [13–27]. In recent years, organic dyes such as eosinY or methylene blue have also
started to be investigated as organic photoredox catalysts under blue to green light irradiation
(λ=ca. 450–550nm)[29–31]. Althoughseveralmetalandnon-metalphotoredoxcatalystshavebeen
developed,rutheniumoriridiumcomplexescoordinatedbypolybipyridylligandsaresurelythemost
effectivecatalystsinthesetransformations,despitethemajordisadvantageoftheirhighcost.
Phthalocyanines,whichareman-madebluecolordyeswithnearlyacenturyofhistory[32,33],are
18π-electronmacro-heterocyclesconsistingoffourisoindolineunitswithaplanarstructure.Theirlarge
conjugated system induces good absorption bands of spectra at 620–700 nm, and their chemical,
Molecules2017,22,1130;doi:10.3390/molecules22071130 www.mdpi.com/journal/molecules
Molecules2017,22,1130 2of12
Molecules 2017, 22, 1130 2 of 12
thermal, and photo stabilities, low-cost and non-toxicity makes them promising photosensitizers
successful application of phthalocyanines for DSSC, they should also be very attractive alternative
for dye-sensitized solar cell (DSSC) applications [34–36]. From the viewpoint of the successful
catalysts to Ru(II) polypyridyl complexes for photoredox perfluoroalkylation reactions. In spite of
applicationofphthalocyaninesforDSSC,theyshouldalsobeveryattractivealternativecatalyststo
their potential performance as photoredox materials, as mentioned above, research on
Ru(II)polypyridylcomplexesforphotoredoxperfluoroalkylationreactions. Inspiteoftheirpotential
phthalocyanines for photoredox radical perfluoroalkylation is rarely reported [37,38]. This is
performanceasphotoredoxmaterials,asmentionedabove,researchonphthalocyaninesforphotoredox
presumably due to the notorious low solubility of phthalocyanines in organic solvents [32,33]. In the
radicalperfluoroalkylationisrarelyreported[37,38]. Thisispresumablyduetothenotoriouslow
last several years, we have reported the design and synthesis of a series of trifluoroethoxy-coated
solubilityofphthalocyaninesinorganicsolvents[32,33]. Inthelastseveralyears,wehavereported
phthalocyanines, and revealed their extraordinary non-aggregation property allowing them to
the design and synthesis of a series of trifluoroethoxy-coated phthalocyanines, and revealed their
become highly soluble in a wide variety of organic solvents [39–45]. We recently reported that
extraordinarynon-aggregationpropertyallowingthemtobecomehighlysolubleinawidevarietyof
trifluoroethoxy-coated boron subphthalocyanine is a very effective catalyst for the radical
organicsolvents[39–45]. Werecentlyreportedthattrifluoroethoxy-coatedboronsubphthalocyanine
fluoroalkylation of alkenes and alkynes under energetically lower red light irradiation [46]. However,
isaveryeffectivecatalystfortheradicalfluoroalkylationofalkenesandalkynesunderenergetically
apart from the advantages of its reactivity following red-light activation (λ = 600–700 nm), boron
lower red light irradiation [46]. However, apart from the advantages of its reactivity following
sruedbp-lhigthhtalaocctyivaantiinoen m(λig=h6t 0h0a–v7e0 a0 pnrmo)b,lbemor,o intss luobnpgh-ttehramlo pchyoantoin-setambiilgihtyt [h4a7v–e49a].p Trohbalte ims, ,ifi ttshleo rnega-ctteiromn
requires very long time, catalytic activity would disappear. We disclose herein the radical
photo-stability [47–49]. That is, if the reaction requires very long time, catalytic activity would
perfluoroalkylation of alkenes, including alkyne, catalyzed by trifluoroethoxy-coated zinc
disappear. Wedisclosehereintheradicalperfluoroalkylationofalkenes,includingalkyne,catalyzed
phthalocyanine under visible light irradiation.
bytrifluoroethoxy-coatedzincphthalocyanineundervisiblelightirradiation.
22.. RReessuullttss aanndd DDiissccuussssiioonn
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saeclceocrtdedin gactcooorduirnpgr etvoi oouusr rpepreovrtio[u46s ].reTphoerdt e[s4i6r]e.d Tpheer fldueosriroeodc typleartfelduoprrooodcutyclta2taeda wparosdoubctat in2aeda awftaesr
o1bhtaiinne8d8 %aftyeire 1ld h( iTna b88le%1 y,iEenldtr (yTa1b).leC 1o, nEtnrotrlye 1x)p. eCroimnternotls esxhpoewrimedenthtse srheoawcteiodn thneo rleoancgtieornp nroo cleoendgeedr
pwriotcheoeudtedlig whitthiroruatd liiagthiot nir,racadtiaaltyiosnt,, ocartaaldydstit, iovre a(dEdnittriviees (E2–n4tr)i.esT 2h–e4)u. sTehseo ufsteBs uo-ff tuBnuc-tfiuonncatliioznedalizziendc
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oTfF TEFOE-OZn-ZPncPdce dcerecaresaesdedp rpordoudcutcyt iyeiledlsd(sE (nEtnrtireises5 ,56, )6.).N Neexxtt,, aaddddiittiivveess wweerree ssccrreeeenneedd aanndd tthhee uussee ooff
aassccoorrbbiicc aacciidd oorr HHaannttzzsscchh eesstteerr rreessuulltteedd iinn aa ddeeccrreeaassee iinn yyiieellddss ((EEnnttrriieess 77,, 88)).. FFiinnaallllyy,, ssttuuddyy ooff ssoollvveenntt
eeffffeecctt rreevveeaalleedd tthhaatts isninggleles oslovlevnetnstssu scuhcahs aMs eMOHeO,HM,e CMNeC,oNr,D oMr SDOMsShOow sehdownoedim npor oivmepmreonvteimneyniet ldins
y(Eienldtrsie (sE9n–tr1i1e)s, 9b–u1t1a)n, binuct raena siencinrecaosne cienn ctorantcieonntgraatvioenh gigahveer hpirgohdeur cptryoideuldct( Eynietlrdy (1E2n).try 12).
TTaabbllee 11.. PPeerrfflluuoorrooooccttyyllaattiioonn rreeaaccttiioonn ooff 11--hheexxeennooll wwiitthh TTFFEEOO--ZZnnPPcc uunnddeerr vviissiibbllee lliigghhtt iirrrraaddiiaattiioonn.. aa

Catalyst Additive
Entry Catalyst Additive Solvent Yield(%)b
(1mol%) (0.35equiv)
Entry Solvent Yield (%) b
(1 mol %) (0.35 equiv)
1 TFEO-ZnPc Naascorbate MeCN/MeOH 88
1 2c TFTEFOE-ZOn-PZcnPc NaasNcoarb aastecorbatMe eCN/MMeeOCHN/MeOH <5 88
3 - Naascorbate MeCN/MeOH <5
2 c TFEO-ZnPc Na ascorbate MeCN/MeOH <5
4 TFEO-ZnPc - MeCN/MeOH <5
3 5 tBu-ZnP- c NaasNcoarb aastecorbatMe eCN/MMeeOCHN/MeOH 45 <5
4 6 TFTEFOE-SOub-ZPcnPc Naascorbate- MeCN/MMeeOCHN/MeOH 77 <5
7 TFEO-ZnPc Ascorbicacid MeCN/MeOH 33
5 tBu-ZnPc Na ascorbate MeCN/MeOH 45
6 TFEO-SubPc Na ascorbate MeCN/MeOH 77
7 TFEO-ZnPc Ascorbic acid MeCN/MeOH 33
8 TFEO-ZnPc Hantzsch ester MeCN/MeOH 24
Molecules2017,22,1130 3of12
Molecules 2017, 22, 1130 Table1.Cont. 3 of 12
9 d,e TFEO-ZnPc Na ascorbate MeCN <5
Catalyst Additive
Entry Solvent Yield(%)b
10 d (1TmFoElO%-)ZnPc (0.35Neqau iavs)corbate MeOH 62
11 f 8 TFTEFOE-ZOn-PZcnPc HantzsNchae astsecrorbaMtee CN/MeODHMSO 24 7
12 g9 d,e TFTEFOE-ZOn-PZcnPc NaascNorab aatsecorbate MeCMNeCN/MeOH <5 93
10d TFEO-ZnPc Naascorbate MeOH 62
a The reactio1n1 off 1-hexTeFnEoOl -(Z1naP 0c.25 mmNoala)s wcoirtbha tneC8F17I (0.3D75M mSOmol) was carried o7ut in the presence
12g TFEO-ZnPc Naascorbate MeCN/MeOH 93
of TFEO-ZnPc (0.0025 mmol) and Na ascorbate (0.0875 mmol) in MeCN (2.0 mL) and MeOH (1.5 mL)
aatT rhoeormeac tteiomnpoefr1a-htuexreen uoln(d1aer0 .i2r5ramdmiaotli)owni twhintCh 8wF1h7Iit(e0 .3L7E5Dm (m1o0l )Ww)a;s bc Yarireileddso wuteirnet hcealpcrueslaentecde obfyT F19EFO-N-ZMnPRc
(0.0025mmol)andNaascorbate(0.0875mmol)inMeCN(2.0mL)andMeOH(1.5mL)atroomtemperatureunder
iorfr acdriuatdioen pwriothduwcht ituesLinEgD P(1h0CWF)3; basY iaenld sinwteerrenacal lcsutalantdedarbdy; 1c9 FR-NeaMctRioonf cwruadse cparrordieudct uosuitn ginP htChFe 3daasrakn;
idn Rteernaacltisotann dtiamrde; cwRaesa c2t4io nh;w e aTsectarraribeudtoyulatminmthoendiaurkm;d bRreoamctiidone t(iTmBeAwBas, 1240 hm;eoTl e%tra) bwutaysl aamdmdoendi;u fm Rberaocmtiiodne
(wTBasA cBa,r1r0iemd oolu%t )fowra 5s ha dwdietdh;ofuRt eNacat iaosncowrabsactear; rgi eRdeaocuttiofonr w5ahsw caitrhroieudt Nouata isnc oMrbeaCteN;g (1R.e0a mctiLo)n awnads McaerOrieHd
outinMeCN(1.0mL)andMeOH(0.75mL).TFEO-ZnPc,trifluoroethoxy-coatedzincphthalocyanine;tBuZnPc,
(0.75 mL). TFEO-ZnPc, trifluoroethoxy-coated zinc phthalocyanine; tBuZnPc, tBu-functionalized zinc
tBu-functionalizedzincphthalocyanine;TFEO-SubPc,trifluoroethoxy-coatedsubphthalocyanine.
phthalocyanine; TFEO-SubPc , trifluoroethoxy-coated subphthalocyanine.
WWiitthh ooppttiimmiizzeedd rreeaaccttiioonn ccoonnddiittiioonnss iinn hhaanndd,, ppeerrfflluuoorrooaallkkyyllaattiioonn ooff aa vvaarriieettyy ooff aallkkeenneess 11 iinn tthhee
pprreesseennccee ooff aa ccaattaalylytticica ammoouunntto offT TFFEEOO-Z-ZnnPPccu nudnedrerv ivsiisbilbeleli glihgthitr riarrdaidatiiaotniown awsaast taetmtepmtepdte(dF i(gFuigreu1re).
V1)a. rVieadrifeudn fcutniocntiaolnizaeldizeadlk aelnkeesne(1s )(1h)a hvainvgintgo tsoyslyatlae,teh, ahlaolgoegnesn,sc, acrabrbamamataet,e,a annddk keettoonnee sshhoowweedd ggoooodd
rreeaaccttiivviittyy ttoo ffuurrnniisshh ppeerrfflluuoorrooaallkkyylalatteedd ccoommppoouunndds s(2()2 )afatfetre r1 1h hirrirardaidaitaiotino.n T.hTe hreearcetaiocnti ocnouclodu blde
bapepalpiepdli etod tionninern-earlk-aelnkee nseubsustbrsattreast e1sj 1ajnadn d1k1,k i,nicnlculduidnign galaklyknyne e11gg, ,inin ccoommppaarraabbllee yyiieellddss,, aanndd ttoo
eelleeccttrroonn--ddeeffiicciieenntt aallkkeennee 11ll iinn aacccceeppttaabbllee yyiieelldd.. OOtthheerr ppeerrfflluuoorrooaallkkyyll iiooddiiddeess,, iinncclluuddiinngg CC44 aanndd CC66
ppeerrflfluuoorrooaallkkyyll cchhaaiinnss,, wweerree ssuucccceessssffuullllyy uusseedd uunnddeerr tthhee ooppttiimmiizzeedd rreeaaccttiioonn ccoonnddiittiioonnss aanndd ddeessiirreedd
pprroodduuccttss 22aabb aanndd 22aacc wweerree aaffffoorrddeedd iinn 11 hh.. TThhee ttrriiflfluuoorroommeetthhyyllaattiioonn rreeaaccttiioonn uussiinngg ttrriiflfluuoorroommeetthhyyll
iiooddiiddee rreeqquuiirreedd aa lloonnggeerr rreeaaccttiioonn ttiimmee ttoo ffuurrnniisshh ccoommppaarraabbllee pprroodduucctt 22aadd iinn 8877%% yyiieelldd..

Figure 1. Perfluoroalkylation reaction of 1 with TFEO-ZnPc under visible light irradiation. The
Figure1.Perfluoroalkylationreactionof1withTFEO-ZnPcundervisiblelightirradiation.Thereaction
reaction of 1 (0.25 mmol) with perfluoroalkyliodide (0.375 mmol) was carried out in the presence of
of1(0.25mmol)withperfluoroalkyliodide(0.375mmol)wascarriedoutinthepresenceofTFEO-ZnPc
TFEO-ZnPc (0.0025 mmol) and Na ascorbate (0.0875 mmol) in MeCN (1.0 mL) and MeOH
(0.0025 mmol) and Na ascorbate (0.0875 mmol) in MeCN (1.0 mL) and MeOH (0.75 mL) at room
(0.75 mL) at room temperature under irradiation with white LED (10 W). Yields are shown as isolated
temperature under irradiation with white LED (10 W). Yields are shown as isolated yield. 2ad:
yield. 2ad: The reaction was carried out for 5 h with an excess amount of CF3I. 2g: 3.7:1 dr. 2j: 1.8:1 dr.
The reaction was carried out for 5 h with an excess amount of CF I. 2g: 3.7:1 dr. 2j: 1.8:1 dr.
RFI: perfluoroalkyliodide. 3
R I:perfluoroalkyliodide.
F
To confirm the reaction mechanism, the time profile of the reaction was investigated. The
trifluoromethylation was selected for this purpose due to its longer reaction time (Figure 2). First,
trifluoromethylation of 1a was carried out with optimized conditions for only 1 h and 65% isolated
yield of product 2ad was obtained, even though an excess amount of CF3I was used (Figure 2a). This
result indicates the difficulty of trifluoromethylation compared with other perfluoroalkylations. Next,
the time profile was further studied by checking the yields of each reaction time with PhCF3 as an
Molecules2017,22,1130 4of12
To confirm the reaction mechanism, the time profile of the reaction was investigated.
Thetrifluoromethylationwasselectedforthispurposeduetoitslongerreactiontime(Figure2). First,
trifluoromethylationof1awascarriedoutwithoptimizedconditionsforonly1hand65%isolated
yield of product 2ad was obtained, even though an excess amount of CF I was used (Figure 2a).
3
TMholiescurleess u20l1t7i,n 2d2,i c11a3t0e sthedifficultyoftrifluoromethylationcomparedwithotherperfluoroalkyla4ti oofn 1s2.
Next,thetimeprofilewasfurtherstudiedbycheckingtheyieldsofeachreactiontimewithPhCF as
3
ainnteinrntearln satalnstdaanrdda wrditwh iat hpaaupsaeu inse liignhlti girhrtaidriraatdioiant i(oFnig(uFrieg u2bre). 2Tbh).e Trehaecrtieoanc tgiorandguraaldlyu aplrloycpeerodceede danedd
agnavdeg caovmepcoarmabplaer aybielledysi aefltdesr aaf 5te hr are5achtiroena ctitmioen, twimhiel,ew thhei lreeathcteiorena dcitdio nnodt ipdroncoetepdr oinc ethede dinartkh.e Tdhaerske.
Trehseusletsr eshsuolwts gsohoodw aggoroeedmaegnret ewmitehn otuwri tphreovuiroupsre rveisouultssr [e4s6u]l atsnd[4 w6]iathn dotwheitrh reopthoertrsr [e1p9o] rotsn [t1h9e] pohnotthoe-
pinhdoutoc-eidn draudciecdalr atrdifilcuaolrtroimflueothroymlateitohny loaft iaolkneonfeasl kweinthe spwhoitthorpehdootxo rceadtaolxysctast.a lysts.
(a)

(b)

Figure2.Thetimeprofileandlight/darkexperimentontrifluoromethylationof1awithTFEO-ZnPc
uFingduerre v2i.s Tibhlee tliimghet pirrorafidleia atniodn l:ig(ha)t/dTrairflku eoxrpoemriemtheynlta otino ntriofflu1oarowmitehthTyFlaEtiOon-Z onfP 1ca uwnidthe rToFpEtOim-ZiznePdc
cuonnddeirt iovnissibfloe rliaghrte aircrtiaodniattiiomne: (oaf) 1Trhiflaunodro5meht;hy(bla)tiToinm oef p1rao fiwleitha nTdFEliOgh-Zt/ndPacr kunedxepre roipmtiemntizoend
tcroiflnduiotrioonmse tfhoyr laat iorenaoctfi1oan wtiimtheT FoEf O1 -Zhn aPnc.d 5 h; (b) Time profile and light/dark experiment on
trifluoromethylation of 1a with TFEO-ZnPc.
AplausiblereactionmechanismshowninScheme1issupportedbypreviousreports[9]andby
theliAgh pt/laduasribkleex rpeaecritmioenn mtmecehnatnioisnme dshaobwovne i.nT Shcehreemaect 1io ins ssutaprptsorwteitdh btyh epreelevciotruosn rterpaonrstfse [r9f]r oanmdN bya
athsceo lribgahtte/dtaorekx ecixtpederTimFEenOt- ZmnePncti(oPnce*d) baybvoviseib. lTehleig rhetatcotifoonr mstathrtes TwFiEthO -tZhen Pecleacntrioonn rtraadnicsafelr( Pfrco−m)a Nnda
tahsecoarnbiaotne troa deixccailterde dTuFcEeOs-tZhnePpce r(Pflcu*o) rboya lvkiysilbioled ildigeh(tR toI f)otromp trhoed uTcFeEtOh-eZpnePrcfl aunoiroona lrkaydlicraald (iPcca−l) (aRnd).
F F
Tthhee arnadioinca rlardeaiccatls rwedituhcaens uthnes apteurrfaluteodromalokiyeltiyodofidthe e(RsuFIb) sttor apterotdoufocer mthaen paelrkfylulorraodailckaylli nrtaedrimcaeld (iRatFe)..
TThheen r,atdhiecaall kreyalcrtasd wiciathl mana yundsoantuatreattehde meloecietrtyo noft otheex csiutebdstrTaFteE Oto- ZfonrPmc aton raelpkryol draudceictahl einTteFrEmOe-dZinaPtec.
aTnhieonn, rtahdei caalkly(Pl artahdAic;aCl mlosaeyd droenacattieo nthcey ecllee)c.trAonno ttoh eerxpciotessdi bTilFitEyOo-fZtnhPiscr teoa crteiponroidsuracde itchael pTrFoEpOag-ZatnioPnc
anion radical (Path A; Closed reaction cycle). Another possibility of this reaction is radical
propagation of the perfluoroalkyl radical intermediate with RFI (Path B; Chain propagation cycle).
The control experiment shows that both plausible reaction passes need an initial electron-transfer
between Na ascorbate and TFEO-ZnPc and the experiment in Figure 1b shows that continuous light
irradiation is essential for the production of a perfluoroalkylated product. From the previous study
[46] and these results in this reaction, Path A and B may work concertedly in this transformation.
Further studies are required to disclose the details of this mechanism.
Molecules2017,22,1130 5of12
oftheperfluoroalkylradicalintermediatewithR I(PathB;Chainpropagationcycle). Thecontrol
F
experimentshowsthatbothplausiblereactionpassesneedaninitialelectron-transferbetweenNa
ascorbateandTFEO-ZnPcandtheexperimentinFigure1bshowsthatcontinuouslightirradiationis
essentialfortheproductionofaperfluoroalkylatedproduct. Fromthepreviousstudy[46]andthese
resultsinthisreaction,PathAandBmayworkconcertedlyinthistransformation. Furtherstudiesare
requiredtodisclosethedetailsofthismechanism.
Molecules 2017, 22, 1130 5 of 12

Scheme 1. Plausible reaction mechanism of trifluoromethylation of alkenes with TFEO-ZnPc.
Scheme1.PlausiblereactionmechanismoftrifluoromethylationofalkeneswithTFEO-ZnPc.
3. Materials and Methods
3. MaterialsandMethods
All reactions were performed in oven-dried glassware under the positive pressure of argon
All reactions were performed in oven-dried glassware under the positive pressure of argon
unless otherwise mentioned. Solvents were transferred via syringe and were introduced into the
unless otherwise mentioned. Solvents were transferred via syringe and were introduced into the
reaction vessels though a rubber septum. All reactions were monitored by thin-layer chromatography
reac(tTioLnCv) ecsasrerilesdt hoouut gohn aa r0u.2b5b merms eMpteurcmk .sAililclar egaecl t(i6o0n-Fs2w54)e. rTeLmC opnlaittoesr ewdebrey vthisiuna-lliazyeedr wchitrho mUVat loigghrat phy
(TLCan)dc aKrMriendO4o iunt woantear/h0e.2at5. CmomlumMne crhcrkomsialitcoagrgaeplh(y6 w0-aFs2 5c4a)r.rieTdL oCutp olna tceosluwmenrse pvaicskueadl iwzeitdh wsiliitcha UV
lightgealn (d60NKM spnhOericianl nweautterarl/ shiezae t6.3–C2o1l0u μmmn, Kcharnotom Cathoegmriacpalh Cyow., aInscc.,a Trroikeydo,o Juatpaonn). cTohlue m1Hn-sNMpaRc ked
4
with(3s0i0l iMcaHgze),l 19(F6-0NNMRsp (h28e2r iMcaHlzn),e auntdra 1l3Cs-iNzeM6R3 (–12215 0MµHmz), spKeacntrtao foCr hsoelmutiicoanl inC Co.D,CInl3c w.,eTreo rkeycoor,dJeadp an).
Theo1nH a-N VMarRian( 330000 M(AHgizl)e,n1t 9TFe-NchMnoRlog(2ie8s2, PMalHo zA),ltaon, dCA13, CU-SNAM) Ran(d1 2a5 BMruHkezr) Aspvaenctcrea 5f0o0r (sBorluukteior,n in
CDCBlillwereicrae, rMecAo,r UdeSdA)o. nCaheVmariciaanl s3h0if0ts( A(δg) ialreen etxTpercehsnseodlo igni epsp,mP adloowAnlftioe,ldC Afro,mUS TAM)Sa n(δd =a 0B.0r0u)k oerr CA6Fv6a nce
3
500((δB r=u −k1e6r2,.2B i(lCleDriCcla3),) MasA a,nU inStAer)n.aCl hsetamndicaarlds. hMifatsss (sδp)eacrtrea ewxperree srseecdordinedp ponm ad Sohwimnafidezlud GfrCoMmST-MS
QP5050A (EI-MS) and Shimadzu LCMS-2020 (ESI-MS) (Shimadzu Corporation, Kyoto, Japan).
(δ = 0.00) or C F (δ=−162.2(CDCl )) as an internal standard. Mass spectra were recorded on a
6 6 3
Melting points were recorded on a Buchi M-565 (Büchi Labortechnik AG, Flawil, Switzerland).
Shimadzu GCMS-QP5050A (EI-MS) and Shimadzu LCMS-2020 (ESI-MS) (Shimadzu Corporation,
Infrared spectra were recorded on a JASCO FT/IR-4100 spectrometer (Jasco Corporation, Tokyo,
Kyoto, Japan). Melting points were recorded on a Buchi M-565 (Büchi Labortechnik AG, Flawil,
Japan). Chemicals were purchased and used without further purification unless otherwise noted.
Switzerland). InfraredspectrawererecordedonaJASCOFT/IR-4100spectrometer(JascoCorporation,
MeOH was dried and distilled before use.
Tokyo, JaAplla nre)a.cCtiohnesm wicearles pweerfroermpuedrc huansdeedr iarnraddiuastieodn wbyit hcoomutmfeurrctihalelry pauvariifilacbaleti o1n0 Wun lweshsitoe tLhEeDrw ise
note(dP.anMaesoOnHic wCaosrpdorriaetdioann, dOsdaikstai,l lJeadpabne,f oDrAe1u0sDe.GK60W, 810 lumens). The LEDs were placed at a
dAisltlanrecea cotfi o3–n4s cwme. re performed under irradiation by commercially available 10 W white LED
(Panasonic Corporation, Osaka, Japan, DA10DGK60W, 810 lumens). The LEDs were placed at
3.1. Perfluoroalkylation of Alkenes and Alkynes with TFEOZnPc
adistanceof3–4cm.
A Schlenk tube equipped with a rubber septum and magnetic stir bar was charged with TFEO-
3.1. PerfluoroalkylationofAlkenesandAlkyneswithTFEOZnPc
ZnPc (5.4 mg, 0.0025 mmol, 1 mol %) and Na ascorbate (17.3 mg, 0.0875 mmol, 0.35 equiv). The tube
was degassed by vacuum evacuation and argon backfill (×3) before MeCN (1.0 mL), MeOH (0.75 mL),
A Schlenk tube equipped with a rubber septum and magnetic stir bar was charged with
substrate (0.25 mmol, 1.0 equiv) and perfluoroalkyliodide (0.375 mmol, 1.5 equiv) were added. The
TFEO-ZnPc (5.4 mg, 0.0025 mmol, 1 mol %) and Na ascorbate (17.3 mg, 0.0875 mmol, 0.35 equiv).
mixture was degassed by the freeze-pump-thaw method (×3). The mixture was stirred for 1 h under
Thetubewasdegassedbyvacuumevacuationandargonbackfill(×3)beforeMeCN(1.0mL),MeOH
irradiation by 10 W white LEDs. After the reaction was complete, the mixture was diluted by Et2O
(0.75mL),substrate(0.25mmol, 1.0equiv)andperfluoroalkyliodide(0.375mmol, 1.5equiv)were
and filtered through a pad of silica gel, and the filtrate was concentrated under reduced pressure.
added. Themixturewasdegassedbythefreeze-pump-thawmethod(×3). Themixturewasstirredfor
The crude product was purified by column chromatography on silica gel to give the desired product.
1hunderirradiationby10WwhiteLEDs. Afterthereactionwascomplete,themixturewasdilutedby
Et2O3.a1n.1d. 5fi-Ilotedroe-d6-tpherrofulugohroaopctaydlhoefxasnileic-1a-gole (l,2aaan)d thefiltratewasconcentratedunderreducedpressure.
Thecrudeproductwaspurifiedbycolumnchromatographyonsilicageltogivethedesiredproduct.
Following a general procedure, TFEO-ZnPc (5.4 mg, 0.0025 mmol, 1 mol %), Na ascorbate
(17.3 mg, 0.0875 mmol, 0.35 equiv) alkene 1a (29.5 μL, 0.25 mmol, 1.0 equiv) and C8F17I (99.0 μL, 0.375
mmol, 1.5 equiv) were used in MeCN (1.0 mL) and MeOH (0.75 mL) at room temperature for 1 h. The
crude product was purified by column chromatography on silica gel (hexane/EtOAc = 8:2) to give
perfluoroalkylated product 2a (150.2 mg, 93% yield) as a white solid.
Molecules2017,22,1130 6of12
3.1.1. 5-Iodo-6-perfluorooctylhexane-1-ol(2aa)
Following a general procedure, TFEO-ZnPc (5.4 mg, 0.0025 mmol, 1 mol %), Na ascorbate
(17.3 mg, 0.0875 mmol, 0.35 equiv) alkene 1a (29.5 µL, 0.25 mmol, 1.0 equiv) and C F I (99.0 µL,
8 17
0.375mmol,1.5equiv)wereusedinMeCN(1.0mL)andMeOH(0.75mL)atroomtemperaturefor1h.
Thecrudeproductwaspurifiedbycolumnchromatographyonsilicagel(hexane/EtOAc=8:2)togive
perfluoroalkylatedproduct2a(150.2mg,93%yield)asawhitesolid.
The1H-NMR,19F-NMRspectrummatchedthatreportedin[19].
MS (EI, m/z) 519 [(M − I)+]; 1H-NMR (CDCl , 300 MHz): δ 4.40–4.30 (m, 1H), 3.70–3.66 (m,
3
2H), 3.00–2.70 (m, 2H), 1.90–1.50 (m, 7H); 19F-NMR (CDCl , 282 MHz): δ −81.2 (t, J = 9.0 Hz, 3F),
3
−111.5–−112.5(m,1F),−114.5–−115.5(m,1F),−121.9(brs,2F),−122.3(brs,4F),−123.1(brs,2F),
−123.9(brs,2F),−126.5(brs,2F).
3.1.2. 5-Iodo-6-perfluorohexylhexanol(2ab)
Following a general procedure, TFEO-ZnPc (5.4 mg, 0.0025 mmol, 1 mol %), Na ascorbate
(17.3 mg, 0.0875 mmol, 0.35 equiv) alkene 1a (29.5 µL, 0.25 mmol, 1.0 equiv) and C F I (81.2 µL,
6 13
0.375mmol,1.5equiv)wereusedinMeCN(1.0mL)andMeOH(0.75mL)atroomtemperaturefor1h.
Thecrudeproductwaspurifiedbycolumnchromatographyonsilicagel(hexane/EtOAc=8:2)togive
perfluoroalkylatedproduct2ab(128.4mg,94%yield)asawhitesolid.
The1H-NMR,19F-NMRspectrummatchedthatreportedin[19].
MS (EI, m/z) 419 [(M − I)+]; 1H-NMR (CDCl , 300 MHz): δ 4.39–4.30 (m, 1H), 3.70–3.67 (m,
3
2H), 3.04–2.69 (m, 2H), 1.90–1.49 (m, 7H); 19F-NMR (CDCl , 282 MHz): δ −81.3 (t, J = 9.9 Hz, 3F),
3
−111.7–−112.7(m,1F),−114.7–−115.7(m,1F),−122.3(brs,2F),−123.4(brs,2F),−124.1(brs,2F),
−126.7(brs,2F).
3.1.3. 5-Iodo-6-perfluorobutylhexanol(2ac)
Following a general procedure, TFEO-ZnPc (5.4 mg, 0.0025 mmol, 1 mol %), Na ascorbate
(17.3 mg, 0.0875 mmol, 0.35 equiv) alkene 1a (29.5 µL, 0.25 mmol, 1.0 equiv) and C F I (63.0 µL,
4 9
0.375mmol,1.5equiv)wereusedinMeCN(1.0mL)andMeOH(0.75mL)atroomtemperaturefor1h.
Thecrudeproductwaspurifiedbycolumnchromatographyonsilicagel(hexane/EtOAc=8:2)togive
perfluoroalkylatedproduct2ac(99.3mg,89%yield)asawhitesolid.
The1H-NMR,19F-NMRspectrummatchedthatreportedin[50].
MS (EI, m/z) 319 [(M − I)+]; 1H-NMR (CDCl , 300 MHz): δ 4.39–4.30 (m, 1H), 3.71–3.67 (m,
3
2H), 2.98–2.69 (m, 2H), 1.89–1.48 (m, 7H); 19F-NMR (CDCl , 282 MHz): δ −81.5 (t, J = 9.9 Hz, 3F),
3
−111.9–−112.9(m,1F),−115.1–−116.0(m,1F),−125.1(brs,2F),−126.4(brs,2F).
3.1.4. 5-Iodo-6-trifluoromethylhexanol(2ad)
A Schlenk tube equipped with a rubber septum and a magnetic stir bar was charged with
TFEO-ZnPc (5.4 mg, 0.0025 mmol, 1 mol %) and Na ascorbate (17.3 mg, 0.0875 mmol, 0.35 equiv).
Thetubewasdegassedbyvacuumevacuationandargonbackfill(×3)beforeMeCN(1.0mL),MeOH
(0.75 mL) and alkene 1a (29.5 µL, 0.25 mmol, 1.0 equiv) were added. The mixture was degassed
bythefreeze-pump-thawmethod(×3). CF I(1.45g,7.32mmol,29.3equiv)inaballoonwasthen
3
addedtothetubeviaaneedlethencooledto−78◦Cinanethanolbath. Themixturewaswarmedto
roomtemperatureandstirredfor5hunderirradiationby10WwhiteLEDs. Afterthereactionwas
complete,themixturewasdilutedbyEt Oandfilteredthroughapadofsilicagel,andthefiltratewas
2
concentratedunderreducedpressure. Thecrudeproductwaspurifiedbycolumnchromatographyon
silicagel(hexane/EtOAc=8:2)togivedesiredproduct2ad(64.2mg,87%yield)asawhitesolid.
The1H-NMR,19F-NMRspectrummatchedthatreportedin[51].
MS(EI,m/z)169[(M−I)+];1H-NMR(CDCl ,300MHz): δ=4.25–4.16(m,1H),3.71–3.66(m,2H),
3
2.98–2.74(m,2H),1.86–1.44(m,7H);19F-NMR(CDCl ,282MHz): δ=−64.4(t,J=10.4Hz,3F).
3
Molecules2017,22,1130 7of12
3.1.5. 5-Iodo-6-perfluorooctylhexyll-4-methylbenzenesulfonate(2b)
Following a general procedure, TFEO-ZnPc (5.4 mg, 0.0025 mmol, 1 mol %), Na ascorbate
(17.3 mg, 0.0875 mmol, 0.35 equiv) alkene 1b (63.6 mg, 0.25 mmol, 1.0 equiv) and C F I (99.0 µL,
8 17
0.375mmol,1.5equiv)wereusedinMeCN(1.0mL)andMeOH(0.75mL)atroomtemperaturefor1h.
Thecrudeproductwaspurifiedbycolumnchromatographyonsilicagel(hexane/EtOAc=8:2)togive
perfluoroalkylatedproduct2b(184.3mg,92%yield)asawhitesolid.
m.p. =54.3–55.3◦C;HRMS(EI)calcd. forC H F O S[(M−I)+]: 673.0705found673.0724;
21 18 17 3
1H-NMR(300MHz,CDCl ): δ7.82(d,J=8.3Hz,2H),7.36(d,J=8.3Hz,2H),4.29–4.21(m,1H),4.05
3
(t,J =6.2Hz, 2H),2.92–2.66(m, 2H),2.45(s, 3H),1.73–1.46(m, 6H).; 19F-NMR(CDCl , 282MHz):
3
δ−81.2(t,J=9.4Hz,3F),−111.6–−112.6(m,1F),−114.8–−115.8(m,1F),−122.1(brs,2F),−122.4(br
s,4F),−123.3(brs,2F),−124.1(brs,2F),−126.6(brs,2F).;13CNMR(CDCl ,125MHz): δ=144.8,
3
133.0,130.0,127.9,120.0–108.8(m,C F ),69.9,41.6(t,J=20.7Hz),39.4(apparentdoublet,J=1.3Hz),
8 17
27.8,25.8,21.6,19.7;IR(KBr)2940,2362,1599,1352,1202,957,812,660,557cm−1.
3.1.6. 1-Bromo-5-iodo-6-perfluorooctylhexane(2c)
Followingageneralprocedure,TFEO-ZnPc(5.4mg,0.0025mmol,1mol%),Naascorbate(17.3mg,
0.0875mmol,0.35equiv),alkene1c(40.8mg,0.25mmol,1.0equiv)andC F I(99.0µL,0.375mmol,
8 17
1.5equiv)wereusedinMeCN(1.0mL)andMeOH(0.75mL)atroomtemperaturefor1h. Thecrude
productwaspurifiedbycolumnchromatographyonsilicagel(hexane)togiveperfluoroalkylated
product2c(160.3mg,90%yield)asyellowoil.
The1H-NMR,19F-NMRspectrummatchedthatreportedin[19].
HRMS (EI) calcd. for C H BrF [(M − I)+]: 580.9773 found 580.9785; 1H-NMR (CDCl ,
14 11 17 3
300MHz): δ4.37–4.28(m,1H),3.42(t,J=6.6Hz,2H),3.04–2.71(m,2H),2.00–1.54(m,6H);19F-NMR
(CDCl ,282MHz): δ−81.1(t,J=9.9Hz,3F),−111.2–−112.3(m,1F),−114.2–−115.2(m,1F),−121.7
3
(brs,2F),−122.0(brs,4F),−122.9(brs,2F),−123.7(brs,2F),−126.3(brs,2F).
3.1.7. 1,5-Diiodo-6-perfluorooctylhexane(2d)
Followingageneralprocedure,TFEO-ZnPc(5.4mg,0.0025mmol,1mol%),Naascorbate(17.3mg,
0.0875mmol,0.35equiv),alkene1d(52.5mg,0.25mmol,1.0equiv)andC F I(99.0µL,0.375mmol,
8 17
1.5equiv)wereusedinMeCN(1.0mL)andMeOH(0.75mL)atroomtemperaturefor1h. Thecrude
productwaspurifiedbycolumnchromatographyonsilicagel(hexane)togiveperfluoroalkylated
product2d(178.3mg,94%yield)asyellowoil.
The1H-NMR,19F-NMRspectrummatchedthatreportedin[19].
HRMS(EI)calcd. forC H F I (M)+: 755.8679found755.8651;1H-NMR(CDCl ,300MHz):
14 11 17 2 3
δ4.37–4.29(m,1H),3.21–3.19(m,2H),3.02–2.71(m,2H),1.84–1.56(m,6H);19F-NMR(CDCl ,282MHz):
3
δ−81.2(t,J=9.3Hz,3F),−111.4–−112.3(m,1F),−114.5–−115.5(m,1F),−121.9(brs,2F),−122.3(br
s,4F),−123.1(brs,2F),−123.9(brs,2F),−126.5(brs,2F).
3.1.8. tert-Butyl(2-iodo-3-perfluorooctylpropyl)carbamate(2e)
Following a general procedure, TFEO-ZnPc (5.4 mg, 0.0025 mmol, 1 mol %), Na ascorbate
(17.3mg, 0.0875mmol, 0.35equiv), alkene1e (39.3mg, 0.25mmol, 1.0equiv)and C F I(99.0 µL,
8 17
0.375mmol,1.5equiv)wereusedinMeCN(1.0mL)andMeOH(0.75mL)atroomtemperaturefor1h.
Thecrudeproductwaspurifiedbycolumnchromatographyonsilicagel(hexane/EtOAc=8:2)togive
perfluoroalkylatedproduct2e(163.6mg,83%yield)asawhitesolid.
The1H-NMR,19F-NMRspectrummatchedthatreportedin[19].
MS(ESI,m/z)726[(M+Na)+];1H-NMR(CDCl ,300MHz):δ5.09–4.99(m,1H),4.43–4.35(m,1H),
3
3.58–3.50(m,2H),2.93–4.73(m,2H),1.45(s,9H);19F-NMR(CDCl ,282MHz): δ−81.2(t,J=8.7Hz,
3
3F), −112.1–−114.7(m, 2F), −121.9(brs, 2F), −122.2(brs, 4F), −123.1(brs, 2F), −123.9(brs, 2F),
−126.5(brs,2F).
Molecules2017,22,1130 8of12
3.1.9. (3-Iodo-4-perfluorooctylbutyl)benzene(2f)
Followingageneralprocedure,TFEO-ZnPc(5.4mg,0.0025mmol,1mol%),Naascorbate(17.3mg,
0.0875mmol,0.35equiv),alkene1f(33.0mg,0.25mmol,1.0equiv)andC F I(99.0µL,0.375mmol,
8 17
1.5equiv)wereusedinMeCN(1.0mL)andMeOH(0.75mL)atroomtemperaturefor1h. Thecrude
productwaspurifiedbycolumnchromatographyonsilicagel(hexane)togiveperfluoroalkylated
product2f(145.4mg,86%yield)asawhitesolid.
The1H-NMRmatchedthatreportedin[52].
HRMS(EI)calcd. forC H F I(M)+: 677.9712found677.9713; 1H-NMR(300MHz,CDCl ):
18 12 17 3
δ7.31(d,J=6.0Hz,2H),7.26–7.20(m,3H),4.31–4.22(m,1H),2.93–2.70(m,4H),2.16–2.08(m,2H).
19F-NMR(282MHz,CDCl ): δ−81.3(t,J=8.5Hz,3F),−111.3–−112.3(m,1F),−114.6–−115.6(m,1F),
3
−122.1(brs,2F),−122.4(brs,4F),−123.2(brs,2F),−124.1(brs,2F),−126.6(brs,2F).
3.1.10. 3-Iodo-4-perfluorooctyldobut-3-en-1-ol(2g)
Following a general procedure, TFEO-ZnPc (5.4 mg, 0.0025 mmol, 1 mol %), Na ascorbate
(17.3mg, 0.0875mmol, 0.35equiv), alkyne1g(17.5mg, 0.25mmol, 1.0equiv)andC F I(99.0µL,
8 17
0.375mmol,1.5equiv)wereusedinMeCN(1.0mL)andMeOH(0.75mL)atroomtemperaturefor1h.
Thecrudeproductwaspurifiedbycolumnchromatographyonsilicagel(hexane/EtOAc=8:2)togive
perfluoroalkylatedproduct2g(128.6mg,83%yield)asawhitesolid.
The1H-NMR,19F-NMRspectrummatchedthatreportedin[19].
HRMS (EI) calcd. for C H F I (M)+: 677.9712 found 677.9711; Data for major isomer of
18 12 17
compound(2g);1H-NMR(CDCl ,300MHz): δ6.49(t,J=13.4Hz,1H),3.89–3.85(m,2H),2.97–2.92
3
(m,2H),1.70(s,1H);19F-NMR(CDCl ,282MHz): δ−81.2(t,J=9.4Hz,3F),−105.3–−105.5(m,2F),
3
−121.8(brs,2F),−122.3(brs,4F),−123.1(brs,2F),−123.4(brs,2F),−126.5(brs,2F).Dataforminor
isomerofcompound(2g);1H-NMR(CDCl ,300MHz): δ6.41(t,J=12.1Hz,1H),3.88–3.84(m,2H),
3
2.95–2.91(m,2H),1.61(s,1H);19F-NMR(CDCl ,282MHz): δ−81.2(t,J=10.0Hz,3F),−109.1–−109.2
3
(m,2F),−121.8(brs,2F),−122.3(brs,4F),−123.2(brs,4F),−126.5(brs,2F).
3.1.11. 2-Iodo-1-perfluorooctyloctene(2h)
Followingageneralprocedure,TFEO-ZnPc(5.4mg,0.0025mmol,1mol%),Naascorbate(17.3mg,
0.0875mmol,0.35equiv),alkene1h(28.0mg,0.25mmol,1.0equiv)andC F I(99.0µL,0.375mmol,
8 17
1.5equiv)wereusedinMeCN(1.0mL)andMeOH(0.75mL)atroomtemperaturefor1h. Thecrude
productwaspurifiedbycolumnchromatographyonsilicagel(hexane)togiveperfluoroalkylated
product2h(160.2mg,97%yield)ascolorlessoil.
HRMS(EI)calcd. forC H F [(M−I)+]: 531.0981found531.0997;1H-NMR(CDCl ,300MHz):
16 16 17 3
δ4.38–4.30(m,1H),3.03–2.68(m,2H),1.87–1.75(m,2H),1.55–1.52(m,8H),0.91–0.90(m,3H);19F-NMR
(CDCl ,282MHz): δ−81.3(t,J=9.4Hz,3F),−111.8–−112.7(m,1F),−114.7–−115.7(m,1F),−122.1
3
(brs,2F),−122.3(brs,4F),−123.2(brs,2F),−124.1(brs,2F),−126.7(brs,2F).;13CNMR(CDCl ,
3
125MHz): δ=106.4–120.8(m,C F ),41.7(t,J=20.6Hz),40.3(apparentdoublet,J=1.3Hz),31.4,29.5,
8 17
28.2,22.5,20.9,14.0(apparentdoublet,J=5.0Hz);IR(NaCl)2932,2860,1468,1434,1368,1206,1151,
705,657,559cm−1.
3.1.12. 5-Iodo-6-perfluorooctylhexane-2-one(2i)
Following a general procedure, TFEO-ZnPc (5.4 mg, 0.0025 mmol, 1 mol %), Na ascorbate
(17.3 mg, 0.0875 mmol, 0.35 equiv), alkene 1i (24.5 mg, 0.25 mmol, 1.0 equiv) and C F I (99.0 µL,
8 17
0.375mmol,1.5equiv)wereusedinMeCN(1.0mL)andMeOH(0.75mL)atroomtemperaturefor1h.
Thecrudeproductwaspurifiedbycolumnchromatographyonsilicagel(hexane/EtOAc=9:1)togive
perfluoroalkylatedproduct2i(137.6mg,85%yield)asawhitesolid.
m.p. = 42.4–43.3 ◦C; HRMS (EI) calcd. for C H F O [(M − I)+]: 517.0460 found 517.0447;
14 10 17
1H-NMR (CDCl , 300 MHz): δ 4.40–4.32 (m, 1H), 3.01–2.63 (m, 4H), 2.20–2.00 (m, 5H); 19F-NMR
3
Molecules2017,22,1130 9of12
(CDCl ,282MHz): δ−81.2(t,J=8.5Hz,3F),−111.6–−112.6(m,1F),−114.4–−115.4(m,1F),−122.0
3
(brs,2F),−122.3(brs,4F),−123.1(brs,2F),−124.0(brs,2F),−126.6(brs,2F).;13CNMR(CDCl ,
3
125MHz): δ=206.5,120.1–106.0(m,C F ),43.7,41.9(t,J=20.6Hz),34.0,30.1,19.8;IR(KBr)2924,
8 17
2370,1714,1434,1250,1146,1034,705,659cm−1.
3.1.13. 1-Iodo-2-perfluorooctylcyclohexane(2j)
Followingageneralprocedure,TFEO-ZnPc(5.4mg,0.0025mmol,1mol%),Naascorbate(17.3mg,
0.0875mmol,0.35equiv),alkene1j(20.5mg,0.25mmol,1.0equiv)andC F I(99.0µL,0.375mmol,
8 17
1.5equiv)wereusedinMeCN(1.0mL)andMeOH(0.75mL)atroomtemperaturefor1h. Thecrude
productwaspurifiedbycolumnchromatographyonsilicagel(hexane)togiveperfluoroalkylated
product2j(150.2mg,96%yield)asawhitesolid.
The1H-NMRspectrummatchedthatreportedin[53].
HRMS(EI)calcd. forC H F [(M−I)+]: 501.0511found501.0511;Dataformajorisomerof
16 16 17
compound(2j);1H-NMR(CDCl ,300MHz): δ4.99–4.95(m,1H),2.75–2.63(m,1H),2.19–1.59(m,8H);
3
19F-NMR(CDCl ,282MHz): δ−81.2(t,J=8.9Hz,3F),−108.6–−109.6(m,1F),−110.3–−111.3(m,1F),
3
−121.0–−121.3(brs,2F),−122.0–−122.3(m,6F),−123.1(brs,2F),−126.5(brs,2F).Dataforminor
isomerofcompound(2j);1H-NMR(CDCl ,300MHz): δ4.74–4.70(m,1H),2.24–2.20(m,1H),2.00–1.37
3
(m,8H);19F-NMR(CDCl ,282MHz): δ−81.2(t,J=8.9Hz,3F),−118.0(brs,2F),−120.3–−122.2(m,
3
8F),−123.1(brs,2F),−126.5(brs,2F).
3.1.14. 2-Iodo-3-perfluorooctylnorbornane(2k)
Followingageneralprocedure,TFEO-ZnPc(5.4mg,0.0025mmol,1mol%),Naascorbate(17.3mg,
0.0875mmol,0.35equiv),alkene1k(23.5mg,0.25mmol,1.0equiv)andC F I(99.0µL,0.375mmol,
8 17
1.5equiv)wereusedinMeCN(1.0mL)andMeOH(0.75mL)atroomtemperaturefor1h. Thecrude
productwaspurifiedbycolumnchromatographyonsilicagel(hexane)togiveperfluoroalkylated
product2k(69.8mg,44%yield)asawhitesolid.
The1H-NMRspectrummatchedthatreportedin[53].
HRMS(EI)calcd. forC H F [(M−I)+]: 513.0511found513.0497;1H-NMR(CDCl ,300MHz):
15 10 17 3
δ 4.33–4.31 (m, 1H), 2.50–2.31 (m, 3H), 1.93–1.30 (m, 6H) ; 19F-NMR (CDCl , 282 MHz): δ −81.3
3
(t,J=9.3Hz,3F),−115.6–116.6(m,1F),−119.0–−120.0(m,1F),−121.3(brs,2F),−122.2–−122.5(m,
6F),−123.2(brs,2F),−126.6(brs,2F).
3.1.15. 3-Iodo-4-(perfluorooctyl)butanenitrile(2l)
Following a general procedure, TFEO-ZnPc (5.4 mg, 0.0025 mmol, 1 mol %), Na ascorbate
(17.3 mg, 0.0875 mmol, 0.35 equiv), alkene 1l (17.8 mg, 0.25 mmol, 1.0 equiv) and C F I (99.0 µL,
8 17
0.375mmol,1.5equiv)wereusedinMeCN(1.0mL)andMeOH(0.75mL)atroomtemperaturefor1h.
Thecrudeproductwaspurifiedbycolumnchromatographyonsilicagel(hexane/EtOAc=9:1)togive
perfluoroalkylatedproduct2l(33.0mg,22%yield)asayellowsolid.
m.p. =81.7–82.7◦C;HRMS(EI)calcd. forC H F NI[(M+)]: 612.9195found612.9209;1H-NMR
12 5 17
(CDCl , 300 MHz): δ 4.49–4.41(m, 1H), 3.34–3.16 (m, 2H), 3.03–2.88 (m, 2H); 19F-NMR (CDCl ,
3 3
282MHz):δ−81.2(t,J=9.4Hz,3F),−111.8–−112.7(m,1F),−114.9–−115.9(m,1F),−122.1(brs,2F),
−122.4(brs,4F),−123.2(brs,2F),−123.9(brs,2F),−126.6(brs,2F);13CNMR(CDCl ,125MHz):
3
δ=120.0–108.3(m,C F ),116.4,40.5(t,J=21.3Hz),30.3(apparentdoublet,J=3.8Hz),5.34(apparent
8 17
doublet,J=3.8Hz);IR(KBr)2958,2920,2366,2258,1371,1203,1149,1117,972,657cm−1.
4. Conclusions
Insummary,wedisclosethefirstphoto-inducedradicalperfluoroalkylationofalkenesandalkyne
inducedbytrifluoroethoxy-coatedzincphthalocyanineasacatalyst. Fromtheviewoftheeaseof
availability,lowercost,andthesubstantialityofphthalocyanines,thisstudywillbeamonumentalwork
Molecules2017,22,1130 10of12
ofphthalocyaninesasphotocatalysts. Furtherstudiestorevealthenewpotentialofphthalocyanines
areunderinvestigationbyourgroup[54].
Acknowledgments:ThisresearchispartiallysupportedbytheAdvancedCatalyticTransformation(ACT-C)from
theJSTAgency,JSPSKAKENHIGrantNumberJP16H01017inPreciselyDesignedCatalystswithCustomized
Scaffolding,andtheAsahiGlassFoundation.K.M.wassupportedbyaGrant-in-AidforJSPSResearchFellow
(15J06852).TrifluoromethyliodideisagiftfromTosohF-TechInc(Shunan,Japan).
AuthorContributions: N.S.conceivedanddesignedtheexperimentsanddirectedtheproject;K.M.andT.H.
performedtheexperimentsandanalyzedthedata;H.A.contributedtocriticaldiscussionandpresentationofthe
results;K.M.andN.S.wrotethepaper.
ConflictsofInterest:Theauthorsdeclarenoconflictsofinterest.
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