Lithium triethylborohydride → (S)-2-(3-aminophenyl)-7-methoxy-8-(3-((S)-7-methoxy-2-(4-methoxyphenyl)-5-oxo-5,11a-dihydro-1H-pyrrolo[2,1-c][1,4]benzodiazepine-8-yloxy)propyloxy)-1H-pyrrolo[2,1-c][1,4]benzodiazepine-5(11aH)-one

Participants

Reaction Steps

A solution of superhydride (0.56 mL, 0.56 mmol, 1.0 M in THF) was added dropwise to a solution of the SEM dilactam (18) (0.271 g, 0.27 mmol) in dry THF (10 mL) at −78° C. under a nitrogen atmosphere. After 1 hr a further aliquot of superhydride solution (0.13 ml, 0.13 mmol) was added and the reaction mixture was allowed to stir for another 0.5 hr, at which time LC-MS indicated that reduction was complete. The reaction mixture was diluted with water and allowed to warm to room temperature. The reaction mixture was partitioned between chloroform and water, the layers were separated and the aqueous layer extracted with additional chloroform (emulsions). Finally the combined organic phase was washed with brine and dried over magnesium sulphate. The reduced product was dissolved in methanol, chloroform and water and allowed to stir in the presence of silica gel for 72 hours The crude product was subjected to flash column chromatography (methanol/chloroform gradient) to afford the desired imine product (150 mg, 0.21 mmol, 77%) after removal of excess eluent from selected fractions.

Provenance & Evidence