4-Chloro-2-methylbenzoic acid → 4-Chloro-2-methylbenzyl Alcohol

反応式

[Cl:1][C:2]1[CH:10]=[CH:9][C:5]([C:6](O)=[O:7])=[C:4]([CH3:11])[CH:3]=1.C(O)C.C(OCC)(OCC)OCC.S(=O)(=O)(O)O>O1CCCC1>[Cl:1][C:2]1[CH:10]=[CH:9][C:5]([CH2:6][OH:7])=[C:4]([CH3:11])[CH:3]=1

参加物

実験手順

A sample of 4-chloro-2-methylbenzoic acid was converted to the ethyl ester using ethanol/triethyl orthoformate/sulfuric acid in >95% yield. Reduction of the ester with LiAiH4/tetrahydrofuran gave 4-chloro-2-methylbenzyl alcohol in 97% yield as a colorless oil. Subsequent treatment with thionyl chloride/pyridine/CH2Cl2 gave the substituted benzyl chloride. The latter, on treatment with 40% excess sodium cyanide in DMF at 90° C. for 20 min. and normal work-up and crystallization from hexane/butyl chloride (2 crops) gave 4-chloro-2-methylbenzyl cyanide in 80% overall yield.