Open AccessC-Alkylation of Chiral Tropane- and Homotropane-Derived Enamines
Author(s) -
David M. Hodgson,
Andrew Charlton,
Robert S. Paton,
Amber L. Thompson
Publication year - 2013
Publication title -
journal of organic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.2
H-Index - 228
eISSN - 1520-6904
pISSN - 0022-3263
DOI - 10.1021/jo3025972
Subject(s) - alkylation , iminium , tropane , chemistry , stereoselectivity , methylene , hydrolysis , enamine , stereochemistry , organic chemistry , catalysis
The synthesis and alkylation of chiral, nonracemic tropane- and homotropane-derived enamines is examined as an approach to enantioenriched α-alkylated aldehydes. The two bicyclic N auxiliaries, which differ by a single methylene group, give opposite senses of asymmetric induction on alkylation with EtI and provide modestly enantioenriched 2-ethylhexanal (following hydrolysis of the alkylated iminium). The observed stereoselectivity is supported by density functional studies of ethylation for both enamines.