Tetrahydrofuran → HCID 54433767, compound

Participants

Reaction Conditions

Reaction Steps

A four-necked flask of 1 L capacity was charged with 60 g (0.159 mol) of (S)-α-(2,3-dimethoxyphenyl)-4-chloro-2-(pivaloylamino)benzyl alcohol, 240 ml of tetrahydrofuran, and 60 ml of methylene chloride and after the atmosphere in the flask was purged with N2 gas, the mixture was stirred with cooling at 10° C. Then, 144 ml of 70% NaAlH2 (OCH2CH2OCH3)2 (Red-Al)/toluene maintained at 10-25° C. was added dropwise under constant stirring. After completion of dropwise addition, the mixture was allowed to stand at room temperature overnight. Next morning, 100 ml of water was added dropwise under ice-cooling and stirring and the mixture was extracted with 923 ml of ethyl acetate. The aqueous layer was further extracted with 923 ml of ethyl acetate. The extracts were combined, and 100 g of anhydrous MgSO4 and 6 g of activated carbon powder for decolorization were added. The mixture was stirred for 10 minutes and, then, filtered. The residue on the filter was washed with 462 ml of ethyl acetate. The filtrate and wash were combined and concentrated under reduced pressure. By this procedure, the objective compound was obtained as a viscous oily residue. Crude yield 62.16 g (optical purity 92.9%, yield 99.6%).

Provenance & Evidence