PREPARATION OF 8-METHOXY-4,8-DIMETHYL-1-(4-ISOPROPYLPHENYL)-NONANE

摘要

Prodn. of 8-methoxy-4,8-dimethyl -1-(4-isopropylphenyl) -1-nonene (I) comprises: (a) reacting isopropylbenzyl chloride (II) with triphenylphosphine in methanol as solvent to form a methanolic soln. of p-isopropylbenzyl triphenylphosphonium chloride (III); (b) reacting this with sodium methoxide then with methoxycitronellal (IV) to give (I); and (c) sepg. (I). (I) may then be hydrogenated in presence of ethanol or hexane and a palladium-carbon catalyst to give 8-methoxy-4,8-dimethyl -1-(4-isopropyl phenyl) nonane (V). - Alternatively (V) is obtd. by: (i) reacting (II) with PPh3 in a solvent (pref. n-octane or n-heptane) to form a slurry of (III); (ii) extracting (III) with MeOH; (iii) reacting the methanolic soln. of (III) with NaOMe then (IV) to produce cis-and trans-(I); and (IV) hydrogenating in a solvent (pref. hexane) in presence of a Pd-C catalyst. - (V) is an insecticide useful for controlling fire ants. (III) remains in soln. or suspension and need not be isolated or purified (cf. known prepns. of (I)). The entire process is in a liq. medium.(0/0)