Reacción #6630

Ecuación de reacción

4,4-dimethylthiochroman

Compound 61

4,4-dimethylthiochroman

acetyl chloride

water

hydrogen chloride

→

title compound

4,4-Dimethyl-6-acetylthiochroman

Disolventes

benzene

Condiciones de reacción

Tratamiento posterior

1. 1
   Temperaturaheated
2. 2
   Temperaturaat reflux for 0.5 hours
3. 3
   TemperaturaAfter being cooled to room temperature
4. 4
   Otrothe organic layer was separated
5. 5
   Extracciónthe aqueous layer extracted with 5×50 ml benzene
6. 6
   Lavadowashed with 5% sodium carbonate, water, saturated NaCl
7. 7
   Secadodried (MgSO4)
8. 8
   OtroThe solvent was removed in vacuo
9. 9
   Otrothe residue purified by flash chromatography (silica; 5% ethyl acetate in hexanes)
10. 10
    workup.DISTILLATIONfollowed by kugelrohr distillation (150 degrees C., 0.7 mm)

Procedimiento

A solution of 14.3g (80.21 mmol) of 4,4-dimethylthiochroman (Compound 61) and 6.76g (86.12 mmol) of acetyl chloride in 65 ml benzene was cooled in an ice bath and treated dropwise with 26.712g (102.54 mmol) of stannic chloride. The mixture was stirred at room temperature for 12 hours, then treated with 65 ml water and 33 ml conc. hydrogen chloride and heated at reflux for 0.5 hours. After being cooled to room temperature, the organic layer was separated and the aqueous layer extracted with 5×50 ml benzene. The recovered organic fractions were combined and washed with 5% sodium carbonate, water, saturated NaCl and then dried (MgSO4). The solvent was removed in vacuo and the residue purified by flash chromatography (silica; 5% ethyl acetate in hexanes) followed by kugelrohr distillation (150 degrees C., 0.7 mm) to give the title compound as a pale yellow oil. PMR (CDCl3) & 1.35 (6H, s), 1.92-1.98 (2H, m) 2.54 (3H, s), 3.02-3.08 (2H, m), 7.13 (1H, d, J~8.6 Hz), 7.58 (1H, dd, J~8.6 Hz, Hz), 7.99 (1H, d, J~2Hz).

Fuente