Triethylborane → 4,6-Diamino-2-ethyl-nicotinonitrile

Participants

Reaction Steps

A mixture of 4,6-diamino-2-bromo-nicotinonitrile from Example 65A (250 mg, 1.2 mmol), Pd(dppf)Cl2 (96 mg, 0.12 mmol), Cs2CO3 (576 mg, 1.8 mmol) in anhydrous DMF was flushed with nitrogen for 5 min before BEt3 (1.0 M solution in hexane, 1.42 mL, 1.4 mmol) was added. The sealed tube was heated@ 120° C. in a microwave reactor for 20 min. The reaction mixture was then partitioned between EtOAc and water, the organic layer was washed with water and brine, dried over Na2SO4, and concentrated in vacuo. The crude residue was purified by silica gel sep-pak, eluting with 30-50% EtOAc in hexane. The product was further purified by recrystalization from EtOAc/hexane to provide the titled compound as a light brown solid (77 mg, 40% yield). 1H NMR (300 MHz, DMSO-d6) δ 6.18 (s, 2H), 6.10 (s, 2H), 5.52 (s, 1H), 2.54 (q, J=7.6 Hz, 2H), 1.14 (t, J=7.6 Hz, 3H); MS (ESI) m/e 163 (M+H)+.

Provenance & Evidence