Cesium carbonate → Tert-butyl 4-(6-cyanopyridin-3-yl)piperazine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

A mixture of the 5-bromopyridine-2-carbonitrile (0.957 g, 5.23 mmol), tert-butyl piperazine-1-carboxylate (1.36 g, 7.32 mmol), cesium carbonate (3.41 g, 10.5 mmol), racemic N,N′-dimethylcyclohexane-1,2-diamine (0.074 g, 0.52 mmol), and copper(I) iodide (0.010 mg, 0.052 mmol) was stirred with 13.1 mL of 1-methylpyrrolidin-2-one and purged with a stream of nitrogen. The reaction was heated to 120° C. for 8 hours. The mixture was diluted with dichloromethane (20 mL) and washed with water (3×20 mL). The organic layer was dried over sodium sulfate, filtered, concentrated, and subjected to purified by silica gel chromatography eluting with 0-50% EtOAc in hexanes. Collection of product containing fractions and removal of solvent yielded to yield tert-butyl 4-(6-cyanopyridin-3-yl)piperazine-1-carboxylate.

Provenance & Evidence