A Convenient Approach to the Enantiopure (1S,2S,4S,5S)-and (1R,2S,4R,5S)-2,5-Bis(phenylmethyl)-1,4-d

• 作 者: 邱丽华 沈宗旋 陈五红 张勇 张雅文
• 机 构: Department of Chemistry and Chemical Engineering, Suzhou University,Department of Chemistry and Chem
• 出 处: Chinese Journal of Chemistry
• 发表日期: 2003年08期
• 关键词: octane methanol chloroform corrected symmetric carbonate operate

Cyclodipeptide (3 S,6S ) bis(phenylmethyl)piperazine 2,5 dione was prepared in high yield by heating phenylalanine methyl ester in toluene under reflux. The reduction of this cyclodipeptide with sodium NaBH 4 BF 3 in DME gave the (2 S,5S ) bis(phenylmethyl)piperazine, which, on heating with ethylene bromide and triethylamine, afforded the title compounds. This method was proved to be generally applicable to the synthesis of C 2 symmetric 2,5 disubstituted 1,4 diazabicyclo[2.2.2]octane from the corresponding natural or unnatural amino acid esters.

The reduction of this cyclodipeptide with sodium NaBH 4 BF 3 in DME gave the (2S, 6S) bis (phenylmethyl) piperazine 2,5 dione was prepared in high yield by heating the phenylalanine methyl ester in toluene under reflux. 5S) bis (phenylmethyl) piperazine, which, on heating with ethylene bromide and triethylamine, afforded the title compounds. This method was proved to be generally applicable to the synthesis of C 2 symmetric 2,5 disubstituted 1,4 diazabicyclo [2.2.2 ] octane from the corresponding natural or unnatural amino acid esters.