Boron tribromide → HCID 86599915, compound

Participants

Reaction Steps

420 mg (0.958 mmol) of the compound 4-{[4-(5-fluoro-2-methoxyphenyl)-2-hydroxy-4-methyl-2-(trifluoromethyl)pentylidene]amino}-2,3-dihydroisoindol-1-one that is described in the paragraph above is mixed with 9.6 ml of a 1 M solution of boron tribromide in dichloromethane, and it is stirred for 1¾ hours at room temperature. The reaction mixture is mixed drop by drop with saturated sodium bicarbonate at −30° C., specifically up to pH 8. After dilution with ethyl acetate, the cold bath is removed and stirred vigorously for 15 minutes. After 2× extraction with ethyl acetate, the organic phases are washed with water and saturated sodium chloride solution. After the solvent is dried (sodium sulfate) and spun off, the residue is chromatographed on a Flashmaster (silica gel, NH2 phase) (mobile solvent dichloromethane/methanol). 67.7 mg (16.6%) of 4-{[8-fluoro-2-hydroxy-5-methoxy-4,4-dimethyl-2-(trifluoromethyl)-1,2,3,4-tetrahydronaphthalen-1-yl]amino}-2,3-dihydroisoindol-1-one (diastereomer A, F1); 12.9 mg (3.2%) of 4-{[8-fluoro-2,5 dihydroxy-4,4-dimethyl-2-(trifluoromethyl)-1,2,3,4-tetrahydronaphthalen-1-yl]amino}-2,3-dihydroisoindol-1-one (diastereomer A, F2), and 32.2 mg (7.9%) of 4-{[8-fluoro-2,5-dihydroxy-4,4-dimethyl-2-(trifluoromethyl)-1,2,3,4-tetrahydronaphthalen-1-yl]amino}-2,3-dihydroisoindol-1-one (diastereomer B, F3) are isolated.

Provenance & Evidence