Trichloroethylene → Biisocrotyl

Participants

Reaction Steps

A portion of the effluent from Example 6 was taken, containing 800 m mole trichloroethylene, 35 m mole 2,5-dimethylhexa-1,5-diene and 91 m mole 1,1-dichloro-4-methylpenta-1,4-diene. This mixture was subjected to fractional distillation, and about 600 m mole of trichloroethylene were removed slowly at ≯ 87° C. The residue was treated with p-toluene sulphonic acid (1% by weight) in an autoclave at 150° for 4 hours under autogeneous pressure. Essentially complete isomerisation of the dienes to their conjugated isomers was effected by this treatment. The mixture was fractionally distilled to yield 2,5-dimethylhexa-2,4-diene (28 m mole) and 1,1-dichloro-4-methylpenta-1,3-diene (80 m mole).

Provenance & Evidence