Abstract: The present invention relates to a process for preparing farnesyl acetone.

Abstract: The present invention relates to a process for preparing farnesyl acetone.

Abstract: E7/Z9 -alkadien-1-ols which may be protected at the hydroxy group are prepared by subjecting a 7-hydroxyheptenal to a Wittig reaction with a phosphorylide to give an acetal compound which is converted by further Wittig reaction with a phosphorylide to an E7/Z9 -alkadienol.

Abstract: Polytetrahydrofuran vinyl ethers of the general formulaH.sub.2 C.dbd.HC--[)O--CH.sub.2 --CH.sub.2 --CH.sub.2 --CH.sub.2 --].sub.n O--R Iwhere R is hydrogen or the CH.dbd.CH radical and n is from 2 to 150, are prepared by a process in which polytetrahydrofuran of the general formulaH--[O--CH.sub.2 --CH.sub.2 --CH.sub.2 --CH.sub.2 --].sub.n OH IIis reacted with acetylene.

Abstract: 3,9-Dihydroxynonyne and its derivatives protected at the 9-OH function, of the general formula I ##STR1## where R is hydrogen or a conventional alcohol protective group, and processes for the preparation of the compounds I.

Abstract: 1-tert-Butoxy-.omega.-alkenes of the general formula ICH.sub.2 .dbd.CH--CH.sub.2).sub.n O--C(CH.sub.3).sub.3 (I)wherein n is an integer from 4 to 10, their preparation and their use for imparting fragrance properties to perfumes or to products to be perfumed, or for improving or modifying the fragrance properties of the said perfumes or products, and scent compositions containing these compounds.

Abstract: A process for the preparation of esters of tetrahydropyran-4-carboxylic acid of the general formula I, where R.sup.1 is an alkyl, cycloalkyl, or aryl group, by treating butyrolactones of the general formula II, where R.sup.2 is a hydrogen atom, an alkyl group, or an acyl group --CO--R.sup.3, R.sup.3 being a hydrogen atom or an alkyl group with from 1 to 6 carbon atoms, with alcohols of the general formula III at temperatures of from 150.degree. C. to 400.degree. C. in the presence of acid catalysts.

Abstract: .gamma.-butyrolactones of the general formula I ##STR1## where R.sup.1 is hydrogen or alkyl of 1 to 4 carbon atoms which may be substituted by lower alkoxy or acyloxy and R.sup.2 is hydrogen or straight-chain or branched alkyl which is unsubstituted or substituted by a functional group or is aryl, are prepared by reacting an alkylene oxide of the general formula II ##STR2## with an acylacetate of the general formla III ##STR3## where R.sup.1 and R.sup.2 have the above meanings and R.sup.3 and R.sup.4 are each alkyl of 1 to 6 carbon atoms or aryl, and R.sup.4 may furthermore be hydrogen, in the presence of a catalyst at elevated temperatures, by a process in which the reaction is carried out in the presence of an alkali metal halide, of an ammonium halide, preferably a quaternary ammonium halide, of a phosphonium halide, of an alkali metal phosphate or of an alkali metal carbonate at from 20.degree. to 200.degree. C. and under from 1 to 50 bar.

Abstract: .beta.-Aryl alcohols for the general forumla I ##STR1## where R.sup.1, R.sup.2 and R.sup.3 are identical or different and each is hydrogen, C.sub.1 -C.sub.20 -alkyl, C.sub.5 -C.sub.7 -cycloalkyl, aryl, C.sub.7 -C.sub.12 -aralkyl or C.sub.7 -C.sub.12 -alkaryl, n is 0, 1, 2, 3 or 4, or where two adjacent R.sup.1 's are linked to form a 5- or 6-membered ring, are prepared by reacting an aromatic of the formula II ##STR2## with an alkylene oxide of the formula III ##STR3## where R.sup.1, R.sup.2 and R.sup.3 have the abovementioned meanings, in the presence of a Friedel-Crafts catalyst, by carrying out the reaction in the presence of a titanium(IV) alcoholate at from -20.degree. to +40.degree. C. in the presence or absence of a solvent.

Abstract: Novel phenylalkylcycloamines, their preparation, agents containing these compounds, and methods for regulating plant growth.

Abstract: An improved process for the preparation of riboflavin by condensation of a 4,5-dimethyl-N-(D)-ribityl-2-phenylazoaniline derivative with barbituric acid in the presence of an acidic condensing agent in an organic solvent, wherein a 4,5-dimethyl-N-(D)-ribityl-2-(o-alkoxyphenylazo)-aniline of the formula IIa ##STR1## where R is alkyl of 1 to 4 carbon atoms, in particular methyl, is reacted with barbituric acid, as well as the novel intermediates of the formula IIa.

Abstract: 3-Formyltetrahydrothiopyrans are prepared by hydrogenating a 3-formyl-5,6-dihydro-2H-thiopyran in the presence of a catalyst containing nickel, cobalt, platinum, copper and/or silver; if necessary, the 3-formyl-5,6-dihydro-2H-thiopyrans are prepared by converting bis-(.beta.-formylethyl) sulfides and/or 3-formyl-4-hydroxytetrahydrothiopyrans in the presence of an acidic catalyst, and, if required, these bis-(.beta.-formylethyl) sulfides and/or 3-formyl-4-hydroxytetrahydrothiopyrans are prepared by reacting an acrolein with hydrogen sulfide (a) in the presence of a basic catalyst and of methylene chloride, aromatic hydrocarbons and/or 1,1,2-trichloroethane as solvents, and/or (b) in the presence of a carboxamide.The compounds obtainable by the process according to the invention are useful starting materials for the preparation of dyes, drugs and pesticides.

Abstract: 3-Formyl-5,6-dihydro-2H-pyran is prepared by conversion of acrolein in the presence of water, acids and halohydrocarbons of 1 to 6 carbon atoms and 1 to 6 halogen atoms as solvents at from 60.degree. to 150.degree. C. The 3-formyl-5,6-dihydro-2H-pyran obtained by the novel process is a valuable starting material for the preparation of dyes and crop protection agents.

Abstract: Novel malondialdehyde tetraalkylacetals and the preparation of malondialdehyde tetraalkylacetals by reacting alkyl formates, oxiranes and alkyl vinyl ethers in the presence of a halide of boron, antimony(V), iron(III), tin(II or IV) and/or zinc.The malondialdehyde tetraalkylacetals obtainable by the process of the invention are valuable starting materials for the preparation of dyes, pest control agents and pharmaceuticals.