Methyl bromoacetate → {4-[(E)-3-(3,4-Dichloro-phenyl)-acryloyl]-7-oxo-[1,4]diazepan-1-yl}-acetic acid methyl ester

Participants

Reaction Conditions

Reaction Steps

A suspension of 2.60 g (8.30 mmol) of 1-[(E)-3-(3,4-dichloro-phenyl)-acryloyl]-[1,4]diazepan-5-one (intermediate 5A) in 46 ml of THF was treated slowly at −78° C. with 9.30 ml (9.30 mmol) of lithium hexamethyldisilylazide 1M in THF. After 20 min at −78° C., the mixture was warmed to nearly −10° C. to go entirely in solution and cooled to −78° C. just after. Then, a solution of 1.18 ml (12.45 mmol) of methyl bromoacetate in 15 ml of THF was added dropwise. Over night, the solution was naturally warmed to RT, poured on aqueous 10% KHSO4 solution and extracted with EtOAc(3×). The organic phase was dried (Na2SO4) and evaporated to give 3.21 g (quant.) of the titled compound as a light brown solid containing max 5% of methyl bromoacetate. MS: 385.3 (MH+, 2Cl).

Provenance & Evidence