Dichloromethane → HCID 86747606, compound

Participants

Reaction Conditions

Reaction Steps

The desired (+)-pinanediol-(S)-1-chloro-5-bromo-pentane-1-boronate is prepared according to the procedure given in Organometallics 3, 1284 (1984). Therefore methylenechloride (9.8 ml) in THF is cooled to -100° C. and n-butyllithium (71.6 ml 1.6M solution, 114.5 mMol) is added over 20 min. After 15 min at -100° C., a cold (-78° C.) solution of (+)-pinanediol-5-bromo-pentane-1-boronate (32,8 g, 104.1 mMol) in THF is added. After additional 1 hr at -100° C. anhydrous ZnCl2 (7.1 g, 52,0 mMol) in THF is added. After additional 15 min at -100° C. the reaction mixture is warmed to room temperature and stirred for 2 hr at this temperature. The solvent is removed in vacuo, the residue is diluted with hexane/water and is extracted several times with hexane. After drying over Na2SO4 and removal of the solvent in vacuo, (+ )-pinanediol-(S)-1-chloro-5-bromo-pentane-1-boronate is obtained as a yellow oil which is used directly in the next step without further purification.

Provenance & Evidence