STEREOCHEMISTRY IN CARBENOID FORMATION BY BROMINE LITHIUM AND BROMINE ZINC EXCHANGE-REACTIONS OF 1,1-DIBROMOALKENES - HIGHER REACTIVITY OF THE STERICALLY MORE HINDERED BROMINE ATOM

被引：58
作者：
HARADA, T
KATSUHIRA, T
OKU, A
机构：
[1] Department of Chemistry, Kyoto Institute of Technology, Kyoto 606, Matsugasaki, Sakyo-ku
来源：
JOURNAL OF ORGANIC CHEMISTRY | 1992年 / 57卷 / 22期
关键词：
D O I：
10.1021/jo00048a002
中图分类号：
O62 [有机化学];
学科分类号：
070303 ; 081704 ;
摘要：
Both lithium and zincate carbenoids (R1-(R2)C=C(Br)M; M = Li and Zn(Bu)2Li) generated by the halogen/metal exchange reaction of 1,1-dibromoalkene 1 with BuLi and (Bu)3ZnLi, respectively, are configurationally stable at low temperatures, but in the presence of excess 1, the lithium carbenoids undergo facile isomerization at the carbenoid carbons. Under kinetically controlled conditions, both the Br/Li and Br/Zn exchange reactions take place preferentially at the sterically more hindered bromine atom of 1.
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页码：5805 / 5807
页数：3
相关论文
共 28 条
[11]   TRIALKYLZINCLITHIUM [R3ZNLI] - NEW REAGENT FOR CONJUGATE ADDITION TO ALPHA,BETA-UNSATURATED KETONES [J].
ISOBE, M ;
KONDO, S ;
NAGASAWA, N ;
GOTO, T .
CHEMISTRY LETTERS, 1977, (06) :679-682
[12]  
Kirmse W., 1971, CARBENE CHEM
[13]   SUBSTITUTION ON CARBENOID CARBON OF ALPHA-HALOCYCLOPROPYLLITHIUM - NOVEL STEREOSELECTIVE SYNTHESIS OF GEMINALLY SUBSTITUTED CYCLOPROPANES [J].
KITATANI, K ;
YAMAMOTO, H ;
HIYAMA, T ;
NOZAKI, H .
BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN, 1977, 50 (08) :2158-2160
[14]   ELIMINATIONS FROM OLEFINS [J].
KOBRICH, G .
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION, 1965, 4 (01) :49-&
[15]   (Z)-2-ETHOXYVINYLLITHIUM - REMARKABLY STABLE AND SYNTHETICALLY USEFUL 1,2-COUNTERPOLARIZED SPECIES [J].
LAU, KSY ;
SCHLOSSER, M .
JOURNAL OF ORGANIC CHEMISTRY, 1978, 43 (08) :1595-1598
[16]   THE MULTIPLE MINIMUM PROBLEM IN MOLECULAR MODELING - TREE SEARCHING INTERNAL COORDINATE CONFORMATIONAL SPACE [J].
LIPTON, M ;
STILL, WC .
JOURNAL OF COMPUTATIONAL CHEMISTRY, 1988, 9 (04) :343-355
[17]   (E)-1-BROMO-3,3-DIETHOXY-1-PROPENE (DIETHYL ACETAL OF 3-BROMOACROLEIN) - A VERSATILE SYNTHON FOR THE SYNTHESIS OF FURANS, BUTENOLIDES, AND (Z)-ALLYL ALCOHOLS [J].
MEYERS, AI ;
SPOHN, RF .
JOURNAL OF ORGANIC CHEMISTRY, 1985, 50 (24) :4872-4877
[18]  
Moss R. A., 1975, CARBENES, V2
[19]  
MOSS RA, 1975, CARBENES, V1
[20]   CARBENOIDS - METAL-ASSISTED IONIZATION [J].
RACHON, J ;
GOEDKEN, V ;
WALBORSKY, HM .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1986, 108 (23) :7435-7436
123