Potassium Iodide → tert-butyl 3(R)-[5-(1-benzyloxycarbonyl-4-piperidyl)-1(R)-ethoxycarbonylpentyl]amino-4-oxo-2,3,4,5-tetrahydro-1,5-benzothiazepine-5-acetate

Participants

Reaction Steps

A mixture of 3(R)-[5-(1-benzyloxycarbonyl-4-piperidyl)-1-ethoxycarbonylpentyl]amino-2,3-dihydro-1,5(5H)-benzothiazepin-4-one (1.0 g), tert-butyl chloroacetate (0.27 g), potassium iodide (0.3 g), potassium carbonate (0.24 g) and N,N-dimethylformamide (10 ml) is stirred for 15 hours at room temperature. The mixture is poured into water (50 ml) and extracted with ethyl acetate (40 ml). The extract is washed with diluted hydrochloric acid, sodium bicarbonate solution and water successively, dried over anhydrous sodium sulfate and concentrated in vacuo. The residue is purified by silica gel column chromatography (hexane:ethyl acetate=2:1) to give firstly tert-butyl 3(R)-[5-(1-benzyloxycarbonyl-4-piperidyl)-1(R)-ethoxycarbonylpentyl]amino-4-oxo-2,3,4,5-tetrahydro-1,5-benzothiazepine-5-acetate (0.45 g) as a colorless oil.

Provenance & Evidence