Design and Synthesis of Novel C2-Symmetric Chiral Piperazines and an Application to Asymmetric Acylation of σ-Symmetric 1,2-Diols
摘要:
A novel alicyclic chiral C-2-symmetric piperazine, (S, S)-7, is designed and synthesized from L-proline. Benzoylation of a series of cyclic and acyclic meso-1,2-diols with a catalytic amount of (S,S)-7 and CuCl2 provided optically active monobenzoates with high enantioselectivity.
Design and Synthesis of Novel C2-Symmetric Chiral Piperazines and an Application to Asymmetric Acylation of σ-Symmetric 1,2-Diols
摘要:
A novel alicyclic chiral C-2-symmetric piperazine, (S, S)-7, is designed and synthesized from L-proline. Benzoylation of a series of cyclic and acyclic meso-1,2-diols with a catalytic amount of (S,S)-7 and CuCl2 provided optically active monobenzoates with high enantioselectivity.
Highly Diastereoselective Desymmetrizations of Cyclo(Pro,Pro): An Enantioselective Strategy toward Phakellstatin and Phakellin
作者:Karine G. Poullennec、Anna T. Kelly、Daniel Romo
DOI:10.1021/ol026140q
日期:2002.8.1
[GRAPHICS]Monoenolates of C-2-symmetric, proline-derived piperazine-2,5-diones were generated and trapped with a variety of electrophiles to produce, in a highly diastereoselective fashion, functionalized diketopiperazines (DKPs). These reactions provide the basis for an asymmetric, desymmetrization strategy toward the marine alkaloids phakellstatin and phakellin, The relative stereochemistry of the functionalized DKPs was confirmed by single-crystal X-ray analysis and/or NOE experiments. Bis-functionalization of the DKPs was also found to proceed with high levels of diastereoselectivity.
Design and Synthesis of Novel <i>C</i><sub>2</sub>-Symmetric Chiral Piperazines and an Application to Asymmetric Acylation of σ-Symmetric 1,2-Diols
A novel alicyclic chiral C-2-symmetric piperazine, (S, S)-7, is designed and synthesized from L-proline. Benzoylation of a series of cyclic and acyclic meso-1,2-diols with a catalytic amount of (S,S)-7 and CuCl2 provided optically active monobenzoates with high enantioselectivity.