chiral bisoxazoline ligands with four asymmetric centers were readily synthesized from the two enantiomers of tartaric acid and several aminoacids via the corresponding bis(β-hydroxylamide)s and dimesylates as successive intermediates. With these novel chiral bisoxazoline ligands, rhodium(I)-catalyzedhydrosilylation of acetophenone was carried out and the effects of the combination of the four asymmetric
(2S,2'S)-Bimorpholine was synthesized starting from (R,R)-tartaric acid ester acetal in six steps in 50% of the total yield. Key steps include: cyanide catalyzed amidation and one-step cyclization with p-toluenesulfonyl imidazole. Derivatization of N,N-dibenzyl bimorpholine afforded quaternary bimorpholinium salts, which were used as chiral phase transfer alkylation catalysts. (c) 2007 Elsevier Ltd. All rights reserved.