Stereoselective synthesis of 3-alkylsulfinylmethylisoxazolines and their use as chiral nucleophiles in the chain elongation of 2,3-O-isopropylidene-d-glyceraldehyde
摘要:
The reaction of racemic 3-methylisoxazolines and enantiomerically pure (R-S)- and (S-S)-methanesulfinates and (R-S)- and (S-S)-ethanesulfmates of 1,2:5,6-di-O-isopropylidene-D-glucofuranose allows enantiomerically pure 3-alkylsulfinylmethylisoxazolines with both absolute configurations at sulfur to be obtained. One of these has been used as a chiral nucleophile in the four carbon homologation of 2,3-O-isopropylidene-D-glyceraldehyde 17. (C) 2001 Elsevier Science Ltd. All rights reserved.
in the Rh-catalyzed asymmetric hydroformylation of styrene. Systematic variation of the phosphite moiety revealed a remarkable effect on the selectivity of the hydroformylationcatalysts. High regioselectivities for 2-phenylpropanal (up to 95%) and moderate enantioselectivity were found under mild reaction conditions (25–40°C, 25 bar of syn gas). The hydroformylation results are explained by the solution
Stereoselective synthesis of 3-alkylsulfinylmethylisoxazolines and their use as chiral nucleophiles in the chain elongation of 2,3-O-isopropylidene-d-glyceraldehyde
The reaction of racemic 3-methylisoxazolines and enantiomerically pure (R-S)- and (S-S)-methanesulfinates and (R-S)- and (S-S)-ethanesulfmates of 1,2:5,6-di-O-isopropylidene-D-glucofuranose allows enantiomerically pure 3-alkylsulfinylmethylisoxazolines with both absolute configurations at sulfur to be obtained. One of these has been used as a chiral nucleophile in the four carbon homologation of 2,3-O-isopropylidene-D-glyceraldehyde 17. (C) 2001 Elsevier Science Ltd. All rights reserved.