Nucleophilic attacks on carbon-carbon double bonds. Part 39. Nucleophile and nucleofuge effects, catalysis and stereochemistry in vinylic substitution of electrophilic nitro olefins
Nucleophilic attacks on carbon–carbon double bonds. Part XXII. Base catalysis, leaving group effects, and solvent effects in several nucleophilic vinylic substitutions by amines
作者:Zvi Rappoport、Alain Topol
DOI:10.1039/p29750000863
日期:——
anilines with 1-chloro-(and 1-bromo-)2,2-dicyano-1-p-nitrophenylethylenes (7) show very mild catalysis by the amine, while the reactions of 1-chloro-(and 1-bromo-)2-cyano-2-methoxycarbonylethylenes (9) with p-cyanoaniline, and of other electrophilic olefins with piperidine and morpholine show no catalysis. The reactivity ratios of the leaving groups in system (6) are: kOMs/kCl= 10·4–59·7; kOTs/kCl=
从1-X-2,2-双乙氧基羰基-1-对硝基苯基乙烯[6; X = Cl,OSO 2 Me(OMs),OSO 2 C 6 H 4 Me- p(OTs),OSO 2 C 6 H 4 Br- p(OBs)]由哌啶和吗啉在MeCN,四氢呋喃(THF)和EtOH和EtOH中的苯硫醇根离子是二阶的(速率常数k obs)。苯胺与1-氯-(和1-溴-)2,2-二氰基-1- p的反应-硝基苯基乙烯(7)显示出非常温和的胺催化作用,而1-氯-(和1-溴-)2-氰基-2-甲氧基羰基乙烯(9)与对氰基苯胺的反应以及其他亲电烯烃与哌啶的反应和吗啉没有催化作用。系统(6)中离去基团的反应比为:k OMs / k Cl = 10·4–59·7;k OTs / k Cl = 10·6-29·9;k OB / K OTs = 1·56–2·85,对于系统(7)和(9),k Br / k Cl= 0·67-1·32。对于大多数系统,溶剂对反应性的影响是MeCN>
Bernasconi, Claude F.; Fassberg, Julianne; Killion Jr., Robert B., Journal of the American Chemical Society, 1990, vol. 112, # 8, p. 3169 - 3177
作者:Bernasconi, Claude F.、Fassberg, Julianne、Killion Jr., Robert B.、Rappoport, Zvi
DOI:——
日期:——
Bernasconi, Claude F.; Fassberg, Julianne; Killion Jr., Robert B., Journal of the American Chemical Society, 1991, vol. 113, # 13, p. 4937 - 4946
作者:Bernasconi, Claude F.、Fassberg, Julianne、Killion Jr., Robert B.、Schuck, David F.、Rappoport, Zvi
DOI:——
日期:——
Kinetics of reactions of amines with .alpha.-nitro-.beta.-substituted-stilbenes in 50% dimethyl sulfoxide-50% water. Search for the intermediate in nucleophilic vinylic substitution reactions
作者:Claude F. Bernasconi、Julianne Fassberg、Robert B. Killion、Zvi Rappoport
DOI:10.1021/jo00302a020
日期:1990.7
Nucleophilic attacks on carbon-carbon double bonds. Part 39. Nucleophile and nucleofuge effects, catalysis and stereochemistry in vinylic substitution of electrophilic nitro olefins