Methyl 2-formyl-6-nitrobenzoate → trans-3,4-Dihydro-2.2-dimethyl-4-(7-nitro-1-oxoisoindolin-2-yl)-6-trifluoromethylsulfonyl-2H-1-benzopyran-3-ol

Participants

Reaction Steps

Following the procedure and working up described in Example 10, but using 0.326 g of trans-4-amino-3,4-dihydro-2,2-dimethyl-6-trifluoromethylsulfonyl-2H-1-benzopyran-3-ol (prepared from its hydrochloride, in turn prepared as described in Preparation 9), 0.224 g of methyl 2-formyl-6-nitrobenzoate, 0.164 g of zinc chloride and 0.075 g of sodium cyanoborohydride, 0.391 g of the title compound, melting at 283°-284° C., were obtained.

Provenance & Evidence