1,2-Dichloroethane → HCID 68864647, compound

Participants

Reaction Steps

Method a) A mixture of 11.81 g 2-methyl-but-2-enoyl chloride (0.10 mol) and 1.36 g zinc chloride (0.01 mol, 0.1 eq.) in 100 ml ethylene chloride was treated with a soln. of 136 g α-pinene ((1S)-(−)/(1R)-(+) 90:10, 1 mol, 10 eq.) in 150 ml ethylene chloride and the resulting mixture was stirred 45 min. at 25° C., 2.5 h at 50° C., and 1 h at 80°. After cooling, the reaction mixture was washed with aq. sat. NaCl soln. and aq. sat. NaHCO3 soln. The aq. phases were extracted with Et2O, dried (Na2SO4), and concentrated. The crude product (48 g) filtered (SiO2, hexane/Et2O 200:6→200:13) and the residue (5.1 g) treated with 1 g LiOH.H2O in 75 ml MeOH at 25° C. for 48 h. The resulting mixture was poured into aq. sat. NaCl soln. and extracted with hexane. The combined org. phases were dried (Na2SO4), concentrated and purified by FC (SiO2, hexane/Et2O 100:3) gave 1.6 g (7.1%) of compound 11.

Provenance & Evidence