名称:
                                Stereoselective intramolecular cycloadditions of homochiral nitrilimines: synthesis of enantiopure (6S)-substituted-2,3,3a,4,5,6-hexahydro-furo[3,4-c]pyrazoles
                             
                            
                                摘要:
                                Starting from (S)-ethyl lactate and (S)-ethyl mandelate the homochiral hydrazonoyl chlorides 4b-d have been synthesised. Their base treatment promoted the in situ generation of the corresponding nitrilimines 5b-d, which gave the enantiopure title compounds with good overall yields and diastereoselectivities. (C) 2004 Elsevier Ltd. All rights reserved.