Chloral → 1,1,1-Trichloro-4-methylpent-4-en-2-ol

Participants

Reaction Conditions

Reaction Steps

A mixture of anhydrous chloral (738 g), isobutylene (309 g), and petroleum ether (boiling range 40° to 60° C, 800 ml) was stirred at a temperature in the range -5° to -8° C whilst aluminium chloride (54.5 g) was added in small portions over a period of 2 hours. The mixture was stirred for a further period of one hour at 0° C. Water (450 ml) was then added over 15 minutes, the temperature being maintained at 0° C, after which the mixture was allowed to attain to the ambient temperature. The organic phase was separated, washed with brine (3 × 250 ml) and dried over anhydrous magnesium sulphate. After removal of the solvent by evaporation under reduced pressure the residual oil was distilled under reduced pressure and the fraction boiling range 101° to 111° C at 16 to 18 mm Hg pressure collected. This was shown by gas liquid chromatographic examination to consist of approximately 90%, 1,1,1-trichloro-2-hydroxy-4-methyl-4-pentene and approximately 10% 1,1,1-trichloro-2-hydroxy-4-methyl-3-pentene. Careful distillation afforded almost pure (by g.l.c.) 1,1,1-trichloro-2-hydroxy-4-methyl-4-pentene as a colourless oil (boiling point 99° -100° C/16 mm Hg).

Provenance & Evidence