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The Aluminum Alkoxide Rearrangement of Epoxides, Part I: The Synthesis of Allylic Alcohols and Glycols Monoethers
Author(s) -
Eschinasi E.H.
Publication year - 1968
Publication title -
israel journal of chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.908
H-Index - 54
eISSN - 1869-5868
pISSN - 0021-2148
DOI - 10.1002/ijch.196800089
Subject(s) - chemistry , alkoxide , allylic rearrangement , epoxide , catalysis , oxygen , carbon fibers , ether , organic chemistry , ether cleavage , cleavage (geology) , polymer chemistry , medicinal chemistry , geotechnical engineering , materials science , fracture (geology) , composite number , composite material , engineering
The rearrangement of epoxides catalyzed by aluminum alkoxides affords a selective way of preparing allylic alcohols in high yields. It takes place in the presence of catalytic amounts of aluminum isopropoxide (AIP) which leads to cleavage of the ether linkage at the site of the more substituted α‐carbon of the oxirane. A mechanism with a six membered transition state involving a concerted proton transfer from the least substituted carbon in β position of the oxirane oxygen is suggested. Mild conditions are sufficient to promote this rearrangement to allylic alcohols with epoxides having a tertiary carbon in α‐position of the oxirane oxygen. However, alkoxide transfer to the cleaved α‐carbon may take place when primary or secondary carbons are the only ones present in the α‐positions of the oxirane oxygen with more drastic conditions and equimolar amounts of AIP. The major product is a mixture of α‐glycol monoethers.