Solvent effects on the asymmetric Pauson–Khand-type reaction by rhodium
作者:Yun Hee Choi、Jaesung Kwak、Nakcheol Jeong
DOI:10.1016/j.tetlet.2009.08.060
日期:2009.11
enantioselectivity of an asymmetric Pauson–Khand-type reaction catalyzed by cationic rhodium are heavily dependent on the solvent. Coordinating solvents, such as THF, provide a faster reaction and better stereoselectivity than non-coordinating solvents, such as toluene. These beneficial effects can be attributed to a significant increase in the more reactive catalytic species of [Rh(bisphosphane ligand)∗(solvent)n]+
1,n-Diols (n = 2 - 5) and 2-hydroxy aldehydes protected with a steric auxiliary are transformed by Pseudomonas lipases with high enantioselectivity, thus allowing the efficient resolution of these molecules and the synthesis of related derivatives with high optical purity.