(2)-Cyohexenyl/cyclohexanone prepn. - by crotonisation of cyclohexanone in the liq. phase with a metal cpd. catalyst

摘要

Prepn. of 2-(1-cyclohexenyl)-cyclohexanone (I) comprises crotonisation of cyclohexanone in the liq. phase at 50-250 degrees C in the presence of a catalyst comprising a Fe, Co or Ni cpd. sufficient to provide =1 mol metal per mol cyclohexanone. The metal cpd. may be e.g. (a) a salt of a 1-20C aliphatic carboxylic acid or a naphthenic acid; (b) a metal alkanolate derived from a 1-6C alkanol; (c) polyacids and heteropoly acids or (d) a complex with a 1,3-diketone or with EDTA. Process gives high yields of (I), which can be dehydrogenated to o-phenylphenol. which is a useful fungicide and preservative. Pref. the catalyst is used in amts. of up to 0.5 mol esp. 10-5 to 10-2 mol per mol cyclohexanone. The crotonisation reaction is carried out e.g. at 50-250 degrees C esp. 120-180 degrees C, and may be operated continuously or discontinuously.