Sodium borohydride → HCID 20740331, compound

Participants

Reaction Conditions

Reaction Steps

In a separate flask, sodium borohydride (3.8 g) was added in portions to isobutyric acid (60 mL) cooled to about 15° C. under nitrogen. After 15 minutes, the reaction was cooled to 0° C. and the above reaction solution containing 2-benzylamino-4-methyl-cyclohex-1-enecarboxylic acid ethyl ester was added dropwise. After stirring for 2 hours, the reaction was carefully quenched with 40 mL of 3 M aqueous hydrochloric acid. The organic layer was separated, and the aqueous layer washed with 50% ethyl acetate/hexanes. After making the aqueous layer basic with 2M sodium hydroxide, extraction with four portions of ethyl acetate was conducted. The organic layer was concentrated to about 50 mL, cooled to 0° C., and made acidic with 30% HBr in propionic acid. After 1 hour, a solid was collected (1.1 g). The mother liquor was made basic and extracted with ethyl acetate. After concentration, the residue was subjected to flash chromatography using hexanes/ethyl acetate to afford 1.31 g of 2-benzylamino-4-methyl-cyclohexanecarboxylic acid ethyl ester.

Provenance & Evidence