Chiral lithium amido sulfide ligands for asymmetric addition reactions of alkyllithium reagents to aldehydes
摘要:
Six chiral amino sulfides have been synthesised from the amino acids phenylalanine. phenylglycine and valine. These amino sulfides were used as chiral ligands in the asymmetric addition of n-butyllithium and metyllithium to various aldehydes at low temperatures. The highest stereoselectivities were obtained with berizaldehyde. resulting in 1-phenyl-1-pentanol and 1-phenyl-1-ethanol in enantiomeric excesses of > 98.5 and 95% respectively. These stereoselectivities were significantly, higher than those induced by the ether analogues. (C) 2003 Elsevier Science Ltd. All rights reserved.
Synthesis of chiral β-amino sulfides and β-amino thiols from α-amino acids
作者:Graeme A. Cran、Colin L. Gibson、Sheetal Handa
DOI:10.1016/0957-4166(95)00197-w
日期:1995.7
Bifurcated routes to two series of chiral secondary beta-amino sulfides 5a - c and 11a - c have been developed from L-proIine and (S)-phenylglycine, respectively. The developed methodology has also led to the synthesis of the tertiary beta-amino thiol 7 and the primary beta-amino sulfide 1 2 from L-proline and (S)-phenylglycine, respectively.