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The SmI2-mediated and H2O-promoted reductive cross-coupling reactions of the L-tartatic It: acid derived nitione (3S,4S)-8 with aldehydes/ketones. and the L-malic acid derived nitrone (S)-6 with aliphatic acyl chlorides have been investigated. respectively (2R,3S,4S)-1,3,4-Trihydroxyprolinol derivatives 9a-f were obtained with high C-2/C-3 trans-selectivities. and 72 28-85 15 diastereoselectivities at the carbinol center from aromatic ketones/aldehydes. while low diastereoselectivities for aliphatic aldehydes Conditions have been established for the syntheses of (2R,3S,4S)-3,4-dihydroxyprolinol derivatives such as 18, by N-O bond cleavage of the corresponding N-hydroxyprolinol derivatives 9b-f, or more conveniently by a one-pot reductive coupling of nitrone 8 and in Situ N-O bond cleavage of the resultant coupling product. The 2-acyl-3-benzyloxy-1-hydroxypyrrolidines 10a-f were formed in 48-82% yields. and in 74 26-78 22 diastereoselectivities. It was revealed that the amount of water required for the reaction is substrate-depending (C) 2010 Elsevier Ltd All rights reserved ; NSF of China [20832005]; National Basic Research Program [2010CBS33206]