Chiral salen-metal complexes as novel catalysts for asymmetric phase transfer alkylations
作者:Yuri N. Belokon、Michael North、Vadim S. Kublitski、Nikolai S. Ikonnikov、Pavel E. Krasik、Viktor I. Maleev
DOI:10.1016/s0040-4039(99)01214-9
日期:1999.8
salen-metal complexes have been tested as catalysts for the C-alkylation of aldimine Schiff's bases of alanine esters with alkyl bromides under phase-transfer conditions (solid sodium hydroxide, toluene, ambient temperature, 1–10% of the catalyst). The best catalyst, which was derived from a Cu(II) complex of (1R,2R or 1S,2S)-[N,N′-bis(2′-hydroxybenzylidene)]-1,2-diaminocyclohexane, gave α-methyl-α-amino
在相转移条件下(固体氢氧化钠,甲苯,环境温度,催化剂的1-10%),手性的Salen-金属络合物已作为催化剂用于醛亚胺Schiff丙氨酸酯与烷基溴的C-烷基化反应中。最好的催化剂是由(1 R,2 R或1 S,2 S)-[ N,N'-双(2'-羟基亚苄基)]-1,2-二氨基环己烷的Cu(II)络合物衍生的,得到对映体过量70-96%的α-甲基-α-氨基酸。