Boron Trichloride → (3R,7S)-3-(4-hydroxy-phenyl)-1-methyl-2-oxo-6-((S)-1-phenyl-propyl)-2,3,5,6,7,8-hexahydro-1H-4-oxa-1,6-diaza-anthracene-7-carboxylic acid

Participants

Reaction Steps

To a solution of (3R,7S)-3-[4-(3,4-dichloro-benzyloxy)-phenyl]-1-methyl-2-oxo-6-((S)-1-phenyl-propyl)-2,3,5,6,7,8-hexahydro-1H-4-oxa-1,6-diaza-anthracene-7-carboxylic acid (1R,2S,5R)-2-isopropyl-5-methyl-cyclohexyl ester (0.2 mmol) in DCM (3 mL) was added 1N BCl3 solution in hexane (0.5 mL) at 0° C. and the mixture was stirred for 3 h. The mixture was evaporated to dryness and the residue was quenched with water. The mixture was basified using sodium bicarbonate solution to pH 7. The residue was extracted with EtOAc and 10% THF. The organic layer was washed and dried to get (3R,7S)-3-(4-hydroxy-phenyl)-1-methyl-2-oxo-6-((S)-1-phenyl-propyl)-2,3,5,6,7,8-hexahydro-1H-4-oxa-1,6-diaza-anthracene-7-carboxylic acid as a yellow solid (122 mg). This solid was used as is for the next step.

Provenance & Evidence