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

Temperature

-78 °C

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%).

1. customsealed tube
2. custompropyne gas bubbled through until the volume
3. temperaturehad increased by approx 10 ml
4. customto reach room temperature
5. additionThe mixture was poured onto water (500 ml)
6. extractionextracted with EtOAc (3×150 ml)
7. washThe combined EtOAc layers were washed with water (3×400 ml), saturated NaCl (150 ml)
8. dry with materialdried over Na2SO4
9. filtrationfiltered through a 1 inch plug of silica
10. customevaporated

ORD record

ord-400ab3ffa1fe43fc8edfbdf55e5e0cf0

Source dataset

uspto-grants-2008_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07442701B2