[H-].[Na+].[NH:3]1[C:11]2[C:6](=[CH:7][CH:8]=[CH:9][CH:10]=2)[C:5]([CH:12]=[O:13])=[CH:4]1.Cl[C:15]([O:17][CH2:18][C:19]1[CH:24]=[CH:23][CH:22]=[CH:21][CH:20]=1)=[O:16].O>C1COCC1>[C:15]([N:3]1[C:11]2[C:6](=[CH:7][CH:8]=[CH:9][CH:10]=2)[C:5]([CH:12]=[O:13])=[CH:4]1)([O:17][CH2:18][C:19]1[CH:24]=[CH:23][CH:22]=[CH:21][CH:20]=1)=[O:16]Sodium hydride (1.99 g, 50% in oil, 41.4 mmol, extracted with hexanes) was stirred in THF (50 ml) in a flame-dried flask at 0° C. under nitrogen. Indole-3-carboxaldehyde (5.00 g, 34.5 mmol) was added as a powder in small portions, and then the mixture was warmed to 40° C. for 30 min. The mixture was again cooled to 0° C., and benzyl chloroformate (4.92 ml, 34.5 mmol) was added. After warming to room temperature and stirring overnight, the mixture was poured into water (50 ml) and extracted with CH2Cl2 (50 ml). The organic layer was washed with water (50 ml), dried with MgSO4, filtered and evaporated to 9.2 g (95%) of a gold-brown oil. Crystallization from hot hexane gave 8.47 g (88%) of white crystalline product: mp 70°-71°
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