2-Chloro-1-cyclohexyl-4-(1,2,2-trichloroethyl)benzene → 3-chloro-4-cyclohexyl-1-ethynylbenzene
Reaction equation
Cl[CH:2](Cl)[CH:3]([C:5]1[CH:10]=[CH:9][C:8]([CH:11]2[CH2:16][CH2:15][CH2:14][CH2:13][CH2:12]2)=[C:7]([Cl:17])[CH:6]=1)Cl.C[Li]>CCOCC>[Cl:17][C:7]1[CH:6]=[C:5]([C:3]#[CH:2])[CH:10]=[CH:9][C:8]=1[CH:11]1[CH2:16][CH2:15][CH2:14][CH2:13][CH2:12]1Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
β.β,α,3-tetrachloro-4-cyclohexylphenylethane (55.8 g.; 0.17 moles) is dissolved in anhydrous ether (100 ml). The solution is cooled in an ice-bath with stirring under nitrogen. Methyl lithium (2.3 M in ether; 300 cc) is added dropwise and the mixture stirred in the icebath for 2.5 hours before destroying the excess methyl lithium with ice. The ethereal fraction is washed thoroughly with saline until the washings are neutral. Removal of solvent gives 3-chloro-4-cyclohexyl-1-ethynylbenzene (b.p. 82°-88°/0.15 m).