Dimethylformamide → 2-Fluoro-6-(prop-1-yn-1-yl)benzaldehyde

Participants

Reaction Conditions

Reaction Steps

A mixture of 2-bromo-6-fluorobenzaldehyde [see Tetrahedron Letters (1992), 33(49), 7499-7502] (4.0 g; 19.7 mmol) and triethylamine (4.12 ml; 29.5 mmol) in anhydrous N,N-dimethylformamide (75 ml) contained within a large (200 ml capacity) sealed tube was cooled to −78° C. and propyne gas bubbled through until the volume had increased by approx 10 ml. To this mixture was added Pd(PPh3)2Cl2 (0.69 g; 0.99 mmol) and CuI (180 mg; 1.97 mmol), the lid was put in place and the tube allowed to reach room temperature and stir for 4 hours after which TLC showed the reaction was complete. The mixture was poured onto water (500 ml) and extracted with EtOAc (3×150 ml). The combined EtOAc layers were washed with water (3×400 ml), saturated NaCl (150 ml), dried over Na2SO4, filtered through a 1 inch plug of silica and evaporated to give the title compound (3.2 g, 100%).

Provenance & Evidence