Triethylamine → [6-Chloro-4-(3,3-dimethyl-but-1-ynyl)-pyridin-3-yl]-carbamic acid tert-butyl ester

Participants

Reaction Conditions

Reaction Steps

To a deoxygenated solution of (6-chloro-4-iodo-pyridin-3-yl)-carbamic acid tert-butyl ester (23.3 g, 65.6 mmol), 3,3-dimethyl-but-1-yne (53.8 g, 0.656 mol), CuI (623 mg, 3.3 mmol) and triethylamine (13.3 g, 0.13 mol) in toluene (150 mL) and water (50 mL) was added Pd(PPh3)2Cl2 (2.30 g, 3.28 mmol) under N2. The mixture was heated at 70° C. and stirred for 24 hours. The solid was filtered off and washed with ethyl acetate (200 mL×3). The filtrate was evaporated under reduced pressure to obtain a residue, which was purified by column (petroleum ether/ethyl acetate=10/1) to give [6-chloro-4-(3,3-dimethyl-but-1-ynyl)-pyridin-3-yl]-carbamic acid tert-butyl ester (15.8 g, 78%). 1H NMR (300 MHz, CDCl3) δ 9.10 (br s, 1H), 7.21 (s, 1H), 6.98 (br s, 1H), 1.53 (s, 9H), 1.36 (s, 9H).

Provenance & Evidence