HCID 21969394, compound → HCID 53896973, compound

Participants

Reaction Steps

A solution of (R)-4-bromo-α-[(methoxycarbonyl)amino]-γ-oxobenzenebutanoic acid (2) (74.35 g) in dichloromethane and triethylsilane (182 ml) was cooled to 0° C. and titanium tetrachloride (99.0 ml) was added dropwise over a period of 15 minutes with stirring. After 5.5 hours, triethylsilane (72 ml) was added, and the mixture was stirred at room temperature for 17 hours and at reflux on the steam bath for 3 hours. The mixture was cooled and poured onto ice. The mixture was extracted twice with diethylether. The combined ether extracts were washed with water and extracted 3 times with 250 ml portions of 10% sodium carbonate solution. The combined extracts were washed with diethylether, cooled in ice, and acidified with concentrated hydrochloric acid. The precipitate was filtered, washed with water, and dried under vacuum to leave a white solid. Crystallization from ethyl acetate/hexane gave the title compound as white crystals (52.7 g, 74%, m.p. 136-137° C.). [α]D =-12° (25° C., CH3OH, c=0.8709).

Provenance & Evidence