Sodium borohydride → HCID 59831715, compound

Participants

Reaction Steps

To a stirring suspension of 3-(1H-indol-5-yl)-3-phenyl-acrylonitrile VII (2.8 g, 11.5 mmol) in 2-propanol (60 ml) at room temperature, under N2 was added NaBH4 (2.8 g, 74 mmol) portionwise over 90 min period. The mixture was refluxed for 20 hours and additional 2-propanol (25 ml) was added to facilitate the stirring. After 40 hours at reflux, additional NaBH4 (0.5 g, 13.2 mmol) was added. After 60 hours at reflux, additional NaBH4 (1 g, 26.4 mmol) and 2-propanol (20 ml) were added. After 110 hours at reflux, the mixture was cooled to room temperature, concentrated and the residue was partitioned between H2O and Et2O. The organic layer was separated, washed with brine, dried over MgSO4, filtered and concentrated. The waxy dark yellow solid was re-subjected to the NaBH4 reduction conditions at reflux for 40 hours. The reaction was cooled to room temperature and worked up as above affording 3-(1H-indol-4-yl)-3-phenyl-propionitrile VIII as a yellow-brown solid which was used as crude mixture for the next reaction.

Provenance & Evidence