Structural and solvent effects on the mechanism of base-induced rearrangement of epoxides to allylic alcohols

被引:40
作者
Morgan, KM
Gronert, S
机构
[1] Coll William & Mary, Dept Chem, Williamsburg, VA 23187 USA
[2] San Francisco State Univ, Dept Chem & Biochem, San Francisco, CA 94132 USA
关键词
D O I
10.1021/jo991619q
中图分类号
O62 [有机化学];
学科分类号
070303 ; 081704 ;
摘要
A combined experimental and computational study is presented which explores the influence of structure and solvent on the base-catalyzed isomerization of cyclopentene- and cyclohexene oxides. Cyclohexene oxide is known to rearrange via a syn beta-elimination in nonpolar solvents. Cyclopentene oxide instead undergoes alpha-elimination to a carbenoid intermediate in nonpolar solvents due to the unusual acidity of the alpha-proton, not because of an unfavorable conformation. In HMPA, cyclopentene oxide undergoes beta-elimination. To explore the origins of this mechanistic change, deuterium-labeled cis-4-tert-butylcyclohexene oxide was rearranged in HMPA and was found to react via anti beta-elimination, as presumably do cyclopentene oxide and other epoxides.
引用
收藏
页码:1461 / 1466
页数:6
相关论文
共 38 条
[1]   Conformational analysis, Part 31. A theoretical and lanthanide induced shift (LIS) investigation of the conformations of some epoxides [J].
Abraham, RJ ;
Castellazzi, I ;
Sancassan, F ;
Smith, TAD .
JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 2, 1999, (01) :99-106
[2]   REACTIVITY OF EPOXIDES .2. EFFECT OF REACTION MEDIUM ON OPENING OF EPOXIDES BY LITHIUM AMIDES [J].
APPARU, M ;
BARRELLE, M .
TETRAHEDRON, 1978, 34 (10) :1541-1546
[3]   An asymmetric synthesis of (1S,4R)-4-amino-2-cyclopentenol derivatives [J].
Asami, M ;
Ogawa, M ;
Inoue, S .
TETRAHEDRON LETTERS, 1999, 40 (08) :1563-1564
[4]   CHANGES OF GROWTH-CONDITIONS IN THE VERTICAL BRIDGMAN-STOCKBARGER METHOD FOR THE SOLIDIFICATION OF ALUMINUM [J].
BARTHOLOMEW, DML ;
HELLAWELL, A .
JOURNAL OF CRYSTAL GROWTH, 1980, 50 (02) :453-460
[5]  
BIERBAUM VM, 1976, J AM CHEM SOC, V98, P4229, DOI 10.1021/ja00430a038
[6]   SOLUTION STRUCTURES OF LITHIUM DIALKYLAMIDES AND RELATED N-LITHIATED SPECIES - RESULTS FROM LI-6-N-15 DOUBLE-LABELING EXPERIMENTS [J].
COLLUM, DB .
ACCOUNTS OF CHEMICAL RESEARCH, 1993, 26 (05) :227-234
[7]   ASYMMETRIC-SYNTHESIS USING HOMOCHIRAL LITHIUM AMIDE BASES [J].
COX, PJ ;
SIMPKINS, NS .
TETRAHEDRON-ASYMMETRY, 1991, 2 (01) :1-26
[8]  
CRANDALL JK, 1983, ORG REACTIONS, V29, P345
[9]   ELECTRONIC EFFECTS IN ELIMINATION REACTIONS .V. BIMOLECULAR CIS ELIMINATIONS . 2-ARYLCYCLOPENTYL TOSYLATES [J].
DEPUY, CH ;
MORRIS, GF ;
SMITH, JS ;
SMAT, RJ .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1965, 87 (11) :2421-&
[10]   CONCERTED BIMOLECULAR ELIMINATIONS AND SOME COMMENTS ON EFFECT OF DIHEDRAL ANGLE ON E2 REACTIONS [J].
DEPUY, CH ;
THURN, RD ;
MORRIS, GF .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1962, 84 (07) :1314-&