Chiral tricarbonyl(η6-cyclobutabenzene)chromium complexes. Diastereoselective synthesis and use in asymmetric cycloaddition reactions
作者:E. Peter Kündig、James Leresche、Lionel Saudan、Gérald Bernardinelli
DOI:10.1016/0040-4020(96)00257-8
日期:1996.5
The intermolecular Diels-Alder reaction of a nonracemic planar chiral (ortho-quinodimethane)Cr(CO)3 intermediate 6 with dienophiles gave, after decomplexation, chiral nonracemic tetralins 23–25. Access to 6 was obtained via enzyme catalyzed acetate hydrolysis of 1-acetoxycyclobutabenzene (13), derivatization of the highly enantioenriched 1-hydroxycyclobutabenzene (S-(+)-8) as the tetrahydropyranyl
非外消旋的平面手性(邻-喹二甲烷)Cr(CO)3中间体6与亲二烯体的分子间Diels-Alder反应在分解后产生了手性的非外消旋四氢化萘23-25。通过酶催化的1-乙酰氧基环丁苯的乙酸水解(13),高度对映体富集的1-羟基环丁苯(S-(+)- 8)的四氢吡喃基醚20非对映选择性络合为Cr(CO)3的方法获得6的通道。 (1-羟基环丁苯)Cr(CO)的阴离子的水解和电荷加速开环3((1S,6aR)-(-)- 4)。