93379-49-8

white to light yellow crystal powde

Preparative Methods of (4R,5R)-2,2-Dimethyl-4,5-bis(hydroxydiphenylmethyl)-1,3-dioxolane: chiral titanates are usually prepared by mixing dichlorodiisopropoxytitanium and a chiral 1,4-diol in toluene. Other solvents such as ether and dichloromethane can also be employed. The alcohol exchange reaction takes place immediately at rt. Wherever necessary, liberated isopropyl alcohol is removed by azeotropic removal with toluene. The chiral 1,4-diols are prepared from dimethyl (or diethyl) tartrate by a two-step procedure comprising acetalization followed by the addition of an aryl Grignard reagent.

Chiral titanates are usually prepared just before use under argon atmosphere. Care should be taken to avoid moisture, especially when a catalytic amount of the reagent is used.