Sodium Carbonate → Methyl [(3S)-5-(4-chlorophenyl)-7-(methyloxy)-2-thioxo-2,3-dihydro-1H-1,4-benzodiazepin-3-yl]acetate

Participants

Reaction Conditions

Reaction Steps

A suspension of P4S10 (85.8 g, 190 mmol) and Na2CO3 (20.5 g, 190 mmol) in 1,2-DCE (1.5 L) at RT was stirred for 1 h before methyl[(3S)-5-(4-chlorophenyl)-7-(methyloxy)-2-oxo-2,3-dihydro-1H-1,4-benzodiazepin-3-yl]acetate (for a preparation see Intermediate 5) (40 g, 107 mmol) was added. The resulting mixture was stirred at 65° C. for 4 h before being cooled and filtered. The solid was washed with DCM and the filtrate washed with sat. NaHCO3. The organic layer was dried over Na2SO4, filtered and concentrated under reduced pressure. The title compound was precipitated from a DCM/i-Pr2O mixture and filtered. The filtrate was then concentrated and purified by flash chromatography (DCM/MeOH: 98/2) to afford another batch of product. The title compound was obtained combining the two fractions (30.2 g, 73%) as a yellow powder. LC/MS: m/z 389 [M(35Cl)+H]+, Rt 3.29 min.

Provenance & Evidence