T. Katagiri et al., Intramolecular S(N)2 reaction alpha- to a trifluoromethyl group: preparation of 1-cyano-2-trifluoromethylcyclopropane, TETRAHEDR-A, 10(13), 1999, pp. 2583-2589
The first intramolecular S(N)2 reaction of alpha-trifluoromethylated second
ary alcohols by a carbanion is described. A stereoselective intramolecular
cyclization of 3-substituted-3-cyano-1-trifluoromethylpropyl sulfonate via
the cyano stabilized carbanion provides 1-substituted-1-cyano-2-trifluorome
thylcyclopropanes in good yields. The product has the opposite configuratio
n to the starting alcohol at the carbon attached to trifluoromethyl group,
revealing the reaction takes place in S(N)2 manner with Walden inversion at
the reaction center. (C) 1999 Elsevier Science Ltd. All rights reserved.