A novel chiral amino alcohol ligand, (1 R,2R,5S,7R,8R,9S ) 9 amino 8 hydroxycedrane was synthesized from cedranediol and reacted with borane to form the corresponding complex, oxazaborolidine, that was used as catalyst in the asymmetric reduction of prochiral ketones. Medium stereoselectivities were obtained.
The reactions of carbonyls with a low-valent titanium reagent prepared by TiCl4with Mg in THF were carried out under ultrasonic action at room temperature for 10 min to1 h and corresponding olefins were obtained in good yields. The results indicate that the titanium-induced reductive coupling of carbonyls to olefins is directly affected by ultra sonic dueto the electron transfer process.
