Abstract: There is disclosed a process for preparing unsaturated ketones especially terpenoid ketones, by subjecting a substituted propargyl alcohol of formula (II) ##STR1## wherein R is a group containing 1 or 2 substituted or unsubstituted alkyl- or alkylene units containing 4 carbon atoms each to a thermal treatment sufficient to rearrange its structure in order to obtain structurally isomeric unsaturated ketones of formula I ##STR2## wherein one of the substituents X.sub.3 and X.sub.4 is hydrogen and the other and Z.sub.2 together form a bond. The process can be effected in the presence of an isomerization catalyst, which leads to high percentage of .alpha...beta.,.gamma...delta.-unsaturated ketones. The ketones of formula I are useful as perfumes and as intermediates for the production of terpenoid compounds.

Abstract: A process for obtaining a stereospecific nerolidol at the .DELTA..sup.6 -position thereof by rectifying a mixture of .DELTA..sup.6 -cis-nerolidol and .DELTA..sup.6 -trans-nerolidol in rectification column having from 10 to 100 theoretical plates with a reflux ratio of from 2 to 200 at a temperature below 230.degree. C. under reduced pressure to separate each stereospecific nerolidol from said mixture.

Abstract: 1,1,1-Trihalogeno-4-methyl pentenes and 1,1-dihalogeno-4-methyl-1,3-pentadienes are produced. These compounds are of value as intermediates for the production of pyrethrin analogs which are of use as insecticides or agricultural chemicals.

Abstract: A process for preparing stereospecific farnesylacetic acid and ester thereof by rectifying a mixture of .DELTA..sup.4,8 -trans- and .DELTA..sup.4 -cis-.DELTA..sup.8 -trans-farnesylacetic acids or esters thereof or .DELTA..sup.4,8 -trans- and .DELTA..sup.4 -cis-.DELTA..sup.8 -trans-farnesylacetic acid or esters thereof or a mixture of four isomers of the said farnesylacetic acids or esters thereof.

Abstract: 2,7,10,15,18,23-Hexamethyltetracosane is a novel compound. This compound is prepared [1] by hydrogenating 2,7,10,15,18,23-hexamethyltetracosa-1,6,18,23-tetraene-11,13-diyne-10,15-d iol [itself a novel compound] or 2,7,10,15,18,23-hexamethyltetracosa-11,13-diyne-10,15-diol, dehydrating the hydrogenated intermediates, and thence hydrogenating the dehydrated precursors, or [2] by selectively, partially hydrogenating the said 10,15-diol compounds and thence hydrogenolyzing the precursor diols, or [3] by hydrogenolyzing the said 10,15-diol compounds, or [4] by hydrogenolyzing the hydrogenated intermediates of the reaction [1]. The compound, 3,6,11-trimethyl-undeca-6,11-dien-1-yl-3-ol, a starting material intermediate, is also a novel compound.

Abstract: 2-Substituted or unsubstituted geranyl actic acid esters represented by the general formula [I], ##STR1## wherein R.sub.1 represents a hydrogen atom or a hydrocarbon and R.sub.5 is the same as R.sub.2, R.sub.3 or R.sub.4 hereinafter defined, are prepared by reacting linalool (II) with 2-substituted or unsubstituted ortho acetic acid ester derivatives represented by the general formula [III] ##STR2## wherein R.sub.2, R.sub.3 and R.sub.4, which are the same or different, each represents an alkyl group or a cycloalkyl group, in the presence of an acidic catalyst.

Abstract: Novel 2,6,10,15,19,23-hexamethyltetracosa-11,13-diin-10,15-diol derivatives. Such derivatives are prepared by oxydative coupling of 3,7,11-trimethyldodeca-1-in-3-ol derivatives or by ethynylation of 6,10-dimethylundecan-2-on derivatives with diacetylene and used as starting materials for preparing squalane.

Abstract: Allenic esters of the formula: ##EQU1## (specific examples of R, R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are given) and a process for the preparation thereof which comprises reacting propargyl alcohol derivatives with 2-substituted ortho-acetic acid esters in the presence of an acidic catalyst. These allenic esters are rearranged in the presence of an alkali catalyst to form .alpha., .beta., .gamma., .delta.-unsaturated carboxylic acid esters and are useful as intermediates in the synthesis of various perfumes, medicines, agricultural chemicals and the like.

Abstract: An alkyne-10,15-diol is synthesized by coupling a 3-alkynol containing methyl groups by using as a catalyst a complex comprised of a halide of a metal of Group VII of the Periodic Table coordinated with an organic phosphorus compound.The so-obtained diol can be formed into squalane [2,6,10,15,19,23-hexamethyl tetracosane] by hydrogenolysis, a combination of hydrogenation and hydrogenolysis or a combination of hydrogenation, dehydration and hydrogenation.