Triphenylphosphine → HCID 13036853, compound

Participants

Reaction Steps

To a cold (0°-5° C.) solution of N2 -[[(phenylmethyl)oxy]carbonyl]-N-[2-[[[(phenylmethyl)oxy]carbonyl]amino]-3-methoxy-3-oxopropoxy]-L-serinamide (6.08 g) in distilled tetrahydrofuran (100 ml) is added triphenylphosphine (3.6 g) followed by diethylazodicarboxylate (2.15 ml, 2.38 g). The reaction mixture is allowed to stir for twelve hours under nitrogen, whereupon 7.0 ml of 1,8-diazabicyclo[5.4.0.]undecan-7-ene is added. After 30 minutes, tetrahydrofuran is removed by evaporation and the resulting residue is partitioned between ethyl acetate and saturated sodium bicarbonate. The aqueous layer is washed once with ethyl acetate, then adjusted to pH 2 with saturated potassium bisulfate, and extracted with ethyl acetate (five times). The combined extracts are dried and concentrated to a crystalline solid (1.8 g). A portion is recrystallized from acetone/hexane (two times) to give an analytical sample, melting point 128°-131° C.

Provenance & Evidence