Inversion of secondary chiral alcohols in toluene with the tunable complex of R3NR′COOH
摘要:
The S(N)2 reaction of enantiomerically pure sulfonates with the tunable complex of R3N-R'COOH in toluene has been extensively studied. It was revealed that the molar ratio of the tertiary amines and carboxylic acids in the complex of R3NR'COOH is crucial for the S(N)2 reaction, and should be tuned for each sulfonate to give the best yield. Fifteen sulfonates 1 and 3-13 (Scheme 2) were prepared and transformed into 22 corresponding inverted esters 2 and 14-24 (Scheme 2) in good to high yields. (C) 2010 Elsevier Ltd. All rights reserved.
A novel asymmetric synthesis of oseltamivir phosphate (Tamiflu) from (−)-shikimic acid
摘要:
Oseltamivir phosphate 1 was synthesized starting from a readily available acetonide, that is, ethyl (3R,4S,5R)-3,4-O-isopropylidene shikimate 2, through a new route via 11 steps and in 44% overall yield. The synthesis described in this article is characterized by two particular steps: the highly regioselective and stereoselective facile nucleophilic replacement of an OMs by ail N-3 group at the C-3 position of ethyl (3R,4S,5R)-3,4-O-bismethanesulfonyl-5-0-benzoyl shikimate 5, and the mild ring-opening of an aziridine with 3-pentanol at the C-1 position of ethyl (1 S,5R,6S)-7-acetyl-5-benzoyloxy-7-azabicyclo[4,1,0]hept-2-ene-3-carboxylate 8. (C) 2008 Elsevier Ltd. All rights reserved.
Inversion of secondary chiral alcohols in toluene with the tunable complex of R3NR′COOH
作者:Xiao-Xin Shi、Chun-Li Shen、Jian-Zhong Yao、Liang-Deng Nie、Na Quan
DOI:10.1016/j.tetasy.2009.12.028
日期:2010.3
The S(N)2 reaction of enantiomerically pure sulfonates with the tunable complex of R3N-R'COOH in toluene has been extensively studied. It was revealed that the molar ratio of the tertiary amines and carboxylic acids in the complex of R3NR'COOH is crucial for the S(N)2 reaction, and should be tuned for each sulfonate to give the best yield. Fifteen sulfonates 1 and 3-13 (Scheme 2) were prepared and transformed into 22 corresponding inverted esters 2 and 14-24 (Scheme 2) in good to high yields. (C) 2010 Elsevier Ltd. All rights reserved.
A novel asymmetric synthesis of oseltamivir phosphate (Tamiflu) from (−)-shikimic acid
作者:Liang-Deng Nie、Xiao-Xin Shi
DOI:10.1016/j.tetasy.2008.11.027
日期:2009.1
Oseltamivir phosphate 1 was synthesized starting from a readily available acetonide, that is, ethyl (3R,4S,5R)-3,4-O-isopropylidene shikimate 2, through a new route via 11 steps and in 44% overall yield. The synthesis described in this article is characterized by two particular steps: the highly regioselective and stereoselective facile nucleophilic replacement of an OMs by ail N-3 group at the C-3 position of ethyl (3R,4S,5R)-3,4-O-bismethanesulfonyl-5-0-benzoyl shikimate 5, and the mild ring-opening of an aziridine with 3-pentanol at the C-1 position of ethyl (1 S,5R,6S)-7-acetyl-5-benzoyloxy-7-azabicyclo[4,1,0]hept-2-ene-3-carboxylate 8. (C) 2008 Elsevier Ltd. All rights reserved.