Ethyl 6-chloronicotinate → Ethyl 6-[(2,2,4,4-tetramethylchroman-6-yl)-ethynyl]nicotinate

Participants

Reaction Conditions

Reaction Steps

A solution of 233 mg (1.09 mmol) of 2,2,4,4-tetramethyl-6-ethynylchroman (Compound 5) and 209 mg (1.09 mmol) of ethyl 6-chloronicotinate (Compound 9s) in 1 ml of triethylamine was degassed and then treated under argon with a powdered mixture of 50 mg (0.26 mmol) of cuprous iodide and 100 mg (0.14 mmol) of bis(triphenylphosphine) palladium (II) chloride. The reaction mixture was heated under argon at 55 degrees C. for 80 h and then cooled to room temperature. The triethylamine was then removed under vacuum and the residue purified by lash chromatography (silica; 5% ethyl acetate in hexanes) to give the title compound as a yellow oil. PMR (CDCl3): & 1.36 (12H, s), 1.42 (3H, t, J~7.2 Hz), 1.85 (2H, s), 4.37 (2H, q, J~7.2 Hz), 6.79 (1H, d, J~4 Hz), 7.34 (1H, dd, J~8.4 Hz, 2.1 Hz), 7.56 (1H, d, J~8.7 Hz), 7.60 (1H, d, J~2.1 Hz), 8.27 (1H, dd, J~8.7 Hz, 2.4 Hz), 9.19 (1H, d, J~2.4 Hz). MS exact mass, m/e 363.1837 (calcd. for C23H25O3N, 363 1834).

Provenance & Evidence