Formic Acid → (3aRS,4RS,6aSR)-2-benzyl-4-(4-bromobenzyl)-5,6,6-trimethyl-tetrahydro-pyrrolo[3,4-c]pyrrole-1,3-dione

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Reaction Conditions

Reaction Steps

A mixture of 3.88 g (9.1 mmol) of (3aRS,4RS,6aSR)-2-benzyl-4-(4-bromo-benzyl)-6,6-dimethyl-tetrahydro-pyrrolo[3,4-c]pyrrole-1,3-dione, 85% formic acid (4.9 g, 90 mmol) and 35% formalin solution (2.6 g, 30 mmol) were heated to 100° C. for 5.5 hours. After cooling 1N NaOH (50 ml) was added and the mixture was extracted four times with dichloromethane. The organic phase was concentrated and the residue was separated chromatographically (hexane/ethyl acetate 3:1+1% triethylamine). 3.45 g of (3aRS, 4RS,6aSR)-2-benzyl-4-(4-bromobenzyl)-5,6,6-trimethyl-tetrahydro-pyrrolo[3,4-c]pyrrole-1,3-dione were isolated as a yellowish oil. FAB-MS: 441 ([M+H]+, 40); 271 (100); 212 (5); 169 (11); 136 (14); 110 (26); 91 (42).

Provenance & Evidence