Patent GB-952342-A (GB)
Title: Unsaturated aliphatic alcohols
IPC: C07C69/587
Filed: 1960-06-23
Abstract: The invention comprises compounds of the general formula: <FORM:0952342/C2/1> wherein R is an unsaturated, branched aliphatic radical and R1 is a hydrogen atom or R and R1 together form a tri- or tetramethylene residue, which may be substituted by alkyl radicals and R11 is an alkyl radical, and the geometric isomers thereof.  The compounds may be prepared by (i) reacting a 1-halogeno-alki-2-ene of the general formula: <FORM:0952342/C2/2> wherein R, R1 and R11 are as defined above and Hal is a chlorine, bromine or iodine atom, with triphenylphosphine to give a triphenyl phosphonium halide which is reacted with a proton acceptor to give a phosphorane and this is in turn reacted with (a) a 1-acyloxy-decan -10- al, the acyl group of which contains up to 4 carbon atoms, and the conjugated unsaturated ester thus obtained is saponified with alkali, or (b) a decan -10- al -1- carboxylic acid ester, the ester group of which contains up to 5 carbon atoms, to give a conjugated unsaturated ester which is subsequently reduced to the desired primary alcohol with a complex metal hydride; (ii) reacting a 1-halogeno-alki -2- ene of the above general formula with (a) a C1-C4 acylate of decan -10- al- -1- ol and zinc, magnesium or lithium, by means of a Grignard or Reformatshy synthesis to give a secondary carbinol which is then dehydrated and the acylate thus obtained is saponified with alkali, or (b) a decon -10- al -1- carboxylic acid ester, the ester group of which contains up to 5 carbon atoms, and zinc, magnesium or lithium, by means of a Grignard or Reformatshy synthesis to give a secondary carbinol which is then dehydrated and the carboxylic acid ester thus formed is reduced with a complex metal hydride. The 1-halogeno-alki-2-ene may be used in a sterically homogeneous form or in the form of mixtures of the stereoizomers and the alcohols or acids produced by the above process may be separated into their geometric isomers. Several proton acceptors are specified.  The 1-halogeno-alki-2-enes of the above general formula are obtained by halogenation in known manner of the corresponding 1-hydroxy-alki-2-enes. Decan-10-al-1-carboxylic acid methyl ester may be obtained by ozonolysis of undecyl-10-ene-acid methyl ester. 1-acyloxy-decan-10-als are obtained by reduction of under-10-ene-acid methyl ester to under-10-en-1-ol by means of complex metal hydrides followed by acylation of the alcohol and ozonolysis of the resulting unsaturated ester. Triphenylphosphine oxide is obtained as a by-product in the reaction between the phosphorane and the ester-aldehyde described in (i) above. Reactions of type (ii) may yield other branched chain products of the type: <FORM:0952342/C2/3> wherein R, R1 and R11 are as defined above and R111 represents an alkoxycarbonyl or acyloxymethyl radical containing up to 5 carbon atoms. Examples are given.ALSO:Insect attractants of the formula <FORM:0952342/A5-A6/1> wherein R is an unsaturated, branched aliphatic radical and R1 is a hydrogen atom or R and R1 together form a tri- or tetramethylene residue, which may be substituted by alkyl radicals and R11 is an alkyl radical, and the geometrical isomers thereof (see Division C2), may be added to pest control agents, particularly insecticides.