Acetic Acid → 1-[4-(3-t-Butyldiphenylsilyloxyazetidine-1-carbonyl)-1,3-oxazol-2-yl]-3-hydroxyazetidine

Participants

Reaction Conditions

Reaction Steps

To a solution of 3-hydroxy-1-(4-methoxycarbonyl-1,3-oxazol-2-yl)azetidine (500 mg, 2.52 mmol) (obtained as described in Reference Example 70(7)) in toluene (25 ml) was added a solution of 0.67 M 3-t-butyldiphenylsilyloxyazetidine (obtained as described in Reference Example 42(2))-trimethylaluminium in toluene (11.3 ml) at room temperature under an atmosphere of nitrogen and the mixture was stirred in an oil bath (80° C.) for 15 minutes. After checking the completion of the reaction, to the reaction mixture were added 10% aqueous acetic acid (20 ml) and ethyl acetate (50 ml) in an ice bath and the mixture was stirred at room temperature for 0.5 hours. To the reaction mixture was added ethyl acetate. The mixture was partitioned between ethyl acetate and water. The organic layer was washed with saturated aqueous sodium hydrogencarbonate solution and saturated aqueous sodium chloride solution, dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure. The residue was purified by chromatography on a silica gel column using methylene chloride:methanol (95:5→9:1) as the eluant to afford 1-[4-(3-t-butyldiphenylsilyloxyazetidine-1-carbonyl)-1,3-oxazol-2-yl]-3-hydroxyazetidine (1.24 g, yield 100%) as a pale brown solid.

Provenance & Evidence