Synthesis and Investigation of C2-Symmetric Optically Active Pyrrolidinium Salts as Chiral Phase-Transfer Catalysts.
作者:Min SHI、Kenichi KAZUTA、Yukihiro SATOH、Yukio MASAKI
DOI:10.1248/cpb.42.2625
日期:——
C2-Symmetric optically active pyrrolidinium salts were synthesized by the reaction of 2, 3 : 4, 5-di-O-benzylidene-(3R, 4R)-dihydroxy-(2S, 5S)-bis(hydroxymethyl)pyrrolidine (2), (3R, 4R)-dimethoxy-(2S, 5S)-bis(methoxymethyl)-pyrrolidine (3), 2, 3 : 4, 5-Di-O-benzylidene-(3R, 4R)-dihydroxy-N-(2-hydroxyethyl)-(2S, 5S)-bis(hydroxymethyl)-pyrrolidine (5), and (3R, 4R)-dimethoxy-N-(2-hydroxyethyl)-(2S, 5S)-bis(methoxymethyl)pyrrolidine (7) with methyl iodide or α, ω-dibromoalkanes. They exhibited low chiral induction activity in the epoxidation of chalcone and in the Darzens condensation of p-chlorobenzaldehyde and phenacyl chloride under phase-transfer conditions.
C2-对称光学活性吡咯烷盐是通过2, 3 : 4, 5-二-O-亚苄基-(3R, 4R)-二羟基-(2S, 5S)-双(羟甲基)吡咯烷(2)、(3R, 4R)-二甲氧基-(2S, 5S)-双(甲氧甲基)吡咯烷(3)、2, 3 : 4, 5-二-O-亚苄基-(3R, 4R)-二羟基-N-(2-羟基乙基)-(2S, 5S)-双(羟甲基)吡咯烷(5)和(3R, 4R)-二甲氧基-N-(2-羟基乙基)-(2S, 5S)-双(甲氧甲基)吡咯烷(7)与甲基碘或α, ω-二溴烷的反应合成的。它们在相转移条件下对查尔酮的环氧化反应以及对对氯苯甲醛和苯甲酰氯的达森缩合反应表现出低手性诱导活性。