Reacción #6656

Ecuación de reacción

2,2,4,4-tetramethyl-6-ethynylthiochroman

Compound 3

2,2,4,4-tetramethyl-6-ethynylthiochroman

ethyl 6-chloro-nicotinate

ethyl 6-chloronicotinate

Compound 98

ethyl 6-chloronicotinate

→

title compound

Ethyl 6-[(2,2,4,4-tetramethyl-thiochroman-6-yl)-ethynyl]nicotinate

Disolventes

triethylamine

Condiciones de reacción

Tratamiento posterior

1. 1
   Otrodegassed
2. 2
   OtroThe mixture was degassed again
3. 3
   Otrothe tube was sealed
4. 4
   Temperaturacooled to room temperature
5. 5
   workup.ADDITIONThe mixture was treated with water and ether
6. 6
   Otrothe organic layer was separated
7. 7
   ExtracciónThe aqueous layer was extracted with ether
8. 8
   Lavadowashed with saturated NaCl solution
9. 9
   Secadodried (MgSO4)
10. 10
    OtroThe solvent was removed in vacuo
11. 11
    Otrothe resultant residue was purified by flash chromatography (silica; 10% ethyl acetate in hexanes)

Procedimiento

A solution of 232 mg (1.01 mmol) of 2,2,4,4-tetramethyl-6-ethynylthiochroman (Compound 3) and 190 mg (1.03 mmol) of ethyl 6-chloro-nicotinate (Compound 98) in 2 ml of triethylamine was placed in a heavy-walled glass tube, degassed, placed under argon and then treated with a powdered mixture of 53 mg (0.28 mmol) of cuprous iodide and 84 mg (0.12 mmol) of bis(triphenylphosphine) palladium (II) chloride. The mixture was degassed again, placed under argon and the tube was sealed. The reaction mixture was heated at 55 degrees C. for 60 h and then cooled to room temperature. The mixture was treated with water and ether and the organic layer was separated. The aqueous layer was extracted with ether. The organic layers were then combined and washed with saturated NaCl solution and then dried (MgSO4). The solvent was removed in vacuo and the resultant residue was purified by flash chromatography (silica; 10% ethyl acetate in hexanes) to give the title compound as a dark yellow oil. PMR (CDCl3): 1.32-1.43 (15H, m), 1.92 (2H, s), 4.38 (2H, q, J~7.1 Hz), 7.28 (1H, dd, J~8.3 Hz, 1.8 Hz), 7.32-7.38 (2H, m), 7.53 (1H, d, J~8.3 Hz), 8.24 (1H, dd, J~8.2 Hz, 2.2 Hz), 9.16 (1H, d, J~2.2 Hz). MS exact mass, m/e 379.1594 (calcd. for C23H25NO2S. 379.1606).

Fuente