Tk. Yang et al., THE STUDY OF LEWIS-ACID EFFECT ON ASYMMETRIC DIELS-ALDER REACTIONS OFNEW 2-SULFINYLBUTADIENES DERIVED FROM (1R,2S,3R)-3-MERCAPTOCAMPHAN-2-OL, Tetrahedron letters, 37(26), 1996, pp. 4537-4540
The Diels-Alder reactions of N-phenylmaleimide and new chiral 2-sulfin
ylbutadienes, which were prepared from MerCO[(1R,2S,3R)-3-mercaptocamp
han-2-ol], produced cycloadducts up to 99% d.e. in the presence of LiC
lO4 at ambient temperature. On the other hand, we found the facial sel
ectivity of the cycloaddition changed greatly among various Lewis acid
s. Copyright (C) 1996 Elsevier Science Ltd