C-alkylation of chiral tropane- and homotropane-derived enamines.
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.
Department of Chemistry, Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA, UK. david.hodgson@chem.ox.ac.uk
David M
DM
Hodgson
Andrew
A
Charlton
Robert S
RS
Paton
Amber L
AL
Thompson
D000447:Aldehydes / Q000737:chemistry; D000478:Alkylation; D000588:Amines / Q000737:chemistry*; D007659:Ketones / Q000737:chemistry; D015394:Molecular Structure; D013237:Stereoisomerism; D014326:Tropanes / Q000737:chemistry*
D000447:Aldehydes; D000588:Amines; D007659:Ketones; D014326:Tropanes; C040669:2-ethylhexanal