The Diels-Alder reactions of m- and p-nitrostyrenes

33 Pages·01.153 MB·English

by  Hylton, Virginia M

This thesis, having been approved by the
special Faculty Committee, is accepted
by the Graduate School of the
University of Wyoming,
in partied fulfillment of the requirements
for the degree o/-lias_ter__of__£.cieiiQ£.____
___________
Dean of the Graduate School.
Date Jyn§_.22jL_i2£i
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
THE DIEIS^ALDSR REACTIONS OF m- AND p-NITROSTYRSNJS
by
Virginia M. Hylton
H
A Thesis
Submitted to the Department
of Chemistry and the Graduate School
of the University of Wyoming in Partial
Fulfillment of Requirements for the Degree of
Master of Science
W'r UTBRARY ^
•* DF THE
UNIVERSITY OF WYOMING
LARAMIE
University of Wyoming
Laramie, Wyoming
June, 1951
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
UMI Number: EP20780
INFORMATION TO USERS
The quality of this reproduction is dependent upon the quality of the copy
submitted. Broken or indistinct print, colored or poor quality illustrations and
photographs, print bleed-through, substandard margins, and improper
alignment can adversely affect reproduction.
In the unlikely event that the author did not send a complete manuscript
and there are missing pages, these will be noted. Also, if unauthorized
copyright material had to be removed, a note will indicate the deletion.
®
UMI
UMI Microform EP20780
Copyright 2007 by ProQuest Information and Learning Company.
All rights reserved. This microform edition is protected against
unauthorized copying under Title 17, United States Code.
ProQuest Information and Learning Company
300 North Zeeb Road
P.O. Box 1346
Ann Arbor, Ml 48106-1346
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
hebard room
ACKNOWLEDGMENT
To Dr, Sara Jane Rhoads, the author wishes to express her
appreciation for directing the experimental work and preparation of
the thesis,
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
TABLE OF CONTENTS
Page
INTRODUCTION........................................................... . • . 1
EXPERIMENTAL RESULTS AND DISCUSSION, 10
EXPERIMENTAL......................................................................................................18
SUMMARY ........................... . . . . . . . . . . . . 25
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
LIST OF TM3LE?
page
TABLE I 17
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
T“R*.R of srtjrHiE
Page
FIliURE 1 . . , ................................................................. 19
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
H W
INTRODUCTION
Isolated examples of the Dieis-Alder synthesis were to be
found in the early chemical literatu re,1a but little significance was
'a J. A. Norton, Chem._ Rev.. 31. 319 (1942); b) H.v. Euler and K. 0.
Josephson, J£§r., £2, 822 (19207; c) 0. Diels, J. Blorn, and W. Koll,
Ann., 44-3. 242 (1925); d) K. Alder, "Newer Methods of Preparative Or­
ganic Chemistry," Interscience Publishers, Inc., Nsw York, N. Y.,
19A8, p. 381 ff.
attached to these until, in 1925, Diels and Alder noted the sim ilarity
between a reaction of benzoquinone with isoprene1^ and a reaction of
azodicarboxylic ester with cyclopentadiene and isoprene derivatives.
In 1928, as a result of three years of research, they published the
first paper setting forth a type of reaction now known as the diene
synthesis.
This reaction involves 1,4-addition of an olefinic compound
to a diene, accompanied by a shift of a double bond of the diene, to
form a new six-membered ring. The following general equation illu s­
trates the path of the Diels-Alder reaction. The di9ne (I) varies with
the groups R and R', and the dienophile (the olefinic component, (II))
varies with the groups R" and R "'.
I II III
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
2
In general the dienophile must be activated by an electro­
negative group conjugated with th9 unsaturated double bond. The re­
action1 a has been observed to proceed most often when the carbonyl
group is so conjugated. This group is not essential, however, for
nitro-, cyano-, and other electronegative groups activate the dienophile
as well.
The diene may be a simple compound such as butadiene or a
more complicated one such as cyclopentadiene. Benzene and its simple
derivatives do not participate as the diene although anethole2 does
2a V. Bruchner and J. Kovacs, J. Org., Cfcem.. 13. 641 (1948);
b Ibid., 14, 65 (1949)
give a 2:1 adduct with maleic anhydride.
Butadiene (I, R=R'=H) reacts readily with acrolein, croton-
aldehyde, maleic anhydride and sim ilar compounds. Butadiene reacts
with 1-nitro-l-pentene (II, R,fe N02, R"'= at 100-110° in six
hours to give a supposedly good yield of adduct.3a In contrast, the
3a K. Alder, H. F. Rickert, and E. Windemuth, |l$r., 71, 2451 (1938);
b L. M. Joshel and L. W. Butz, J. Am. Chem. Soc., 63, 3350 (1941)*
reaction of butadiene with ethylene to give cyclohexene3*3 requires a tem­
perature of 200° for seventeen hours at high pressures. Presumably,
conjugation of the nitro- group with the olefinic bond in the nitropentene
accounts for the difference in activity.
Styrene (IV) possesses the qualities of both a diene and a di­
enophile, but at this point (Jane, 1951) no experiment has been reported
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.