Abstract: A process for the preparation of hydroxylated isoflavones by reacting in a Hoesch reaction using an alkanoic acid alkyl ester as solvent a phenol with a phenylacetonitrile to yield a 1,2-diphenyl-ethanone and transforming the ethanone into an isoflavone by well-known methods.

Abstract: A process for the preparation of hydroxylated isoflavones by reacting in a Hoesch reaction using an alkanoic acid alkyl ester as solvent a phenol with a phenylacetonitrile to yield a 1,2-diphenyl-ethanone and transforming the ethanone into an isoflavone by well-known methods.

Abstract: A process for the manufacture of retinal (I) comprises reacting a 5-(2,6,6-trimethyl-cyclohex-1-enyl)-1,4-pentadiene derivative (IIa) or a 5-(2,6,6-trimethyl-cyclohex-2-enyl)-1,4-pentadiene derivative (IIb) or a 5-(2,6,6-trimethyl-2-cyclohexen-1-ylidene)-1-pentene derivative (IIc) or a 5-(2,6,6-trimethyl-cyclohex-1-enyl)-penta-1-en-4-yne derivative (IId) or a 5-(2,6,6-trimethyl-cyclohex-2-enyl)-penta-1-en-4-yne derivative (IIe) with a 1,3-butadiene derivative H2C?C(CH3)CCH?CHOR4 (III) in the presence of a Lewis or Brönsted acid and subjecting the compound obtained in each case [(IVa), (IVb), (IVc), (IVd) or (IVe), respectively] to basic or acidic conditions to eliminate therefrom the moiety R2H and thus produce, according to the immediate precursor, retinal itself or a particular derivative thereof [(I?), (I?), (Va) or (Vb), respectively] and, where in two cases such derivative is produced featuring a triple bond [derivative (Va) or (Vb)], hydrogenating this to produce retinal (I) or the derivative (I?), resp

Abstract: A process for the manufacture of retinal (I) comprises reacting a 5-(2,6,6-trimethyl-cyclohex-1-enyl)-1,4-pentadiene derivative (IIa) or a 5-(2,6,6-trimethyl-cyclohex-2-enyl)-1,4-pentadiene derivative (IIb) or a 5-(2,6,6-trimethyl-2-cyclohexen-1-ylidene)-1-pentene derivative (IIc) or a 5-(2,6,6-trimethyl-cyclohex-1-enyl)-penta-1-en-4-yne derivative (IId) or a 5-(2,6,6-trimethyl-cyclohex-2-enyl)-penta-1-en-4-yne derivative (IIe) with a 1,3-butadiene derivative H2C?C(CH3)CCH?CHOR4 (III) in the presence of a Lewis or Brönsted acid and subjecting the compound obtained in each case [(IVa), (IVb), (IVc), (IVd) or (IVe), respectively] to basic or acidic conditions to eliminate therefrom the moiety R2H and thus produce, according to the immediate precursor, retinal itself or a particular derivative thereof [(I?), (I?), (Va) or (Vb), respectively] and, where in two cases such derivative is produced featuring a triple bond [derivative (Va) or (Vb)], hydrogenating this to produce retinal (I) or the derivative (I?), resp

Abstract: The claimed invention relates to cyclic dienol ethers of formula (III). wherein R3 is hydrogen and R4 is C1-4 alkoxy or R3 and R4 together form an optionally substituted methylenedioxy group —O—C(R5)(R6)—O—, wherein R5 and R6 are each independently hydrogen, C1-4 alkyl or phenyl.

Abstract: A process for the manufacture of a symmetrical, terminally ring-substituted polyenes by reacting a polyene di(O,O-dialkyl acetal) with a cyclic dienol ether in the presence of a Lewis or Brönsted acid, hydrolyzing the condensation product resulting therefrom and cleaving off alcohol under basic or acidic conditions from the polyene derivative produced at this stage. The novel cyclic dienol ethers, as well as, novel intermediates resulting from the condensation and additional intermediates in this process form further aspects of the invention. The final products are primarily carotenoids, which find corresponding use, e.g., as colorings and pigments for foodstuffs, animal products, etc.

Abstract: A process for the manufacture of a symmetrical, terminally ring-substituted polyenes by reacting a polyene di(O,O-dialkyl acetal) with a cyclic dienol ether in the presence of a Lewis or Brönsted acid, hydrolyzing the condensation product resulting therefrom and cleaving off alcohol under basic or acidic conditions from the polyene derivative produced at this stage. The novel cyclic dienol ethers, as well as, novel intermediates resulting from the condensation and additional intermediates in this process form further aspects of the invention. The final products are primarily carotenoids, which find corresponding use, e.g., as colorings and pigments for foodstuffs, animal products, etc.

Abstract: A process for the manufacture of polyene aldehydes comprises reacting a polyene O,O-ethylene acetal with a 1-alkoxy-1,3-diene in the presence of a Lewis acid or Bronsted acid, hydrolyzing the resulting condensation product and cleaving off alcohol under basic or acidic conditions from the polyene derivative produced at this stage. The novel polyene O,O-ethylene acetals as well as the likewise novel condensation products in this process form further aspects of the invention. The final products are primarily carotenoids which find corresponding use, e.g. as colorants and pigments for foodstuffs, animal products etc.

Abstract: A process for the manufacture of a .gamma.-acetoxy-tiglic aldehyde by reacting a .gamma.-bromotiglic aldehyde or a .gamma.-chlorotiglic aldehyde with sodium acetate or potassium acetate in an organic solvent in the presence of a phase transfer catalyst.

Abstract: A novel process for the manufacture of a .gamma.-halotiglic aldehyde HalH.sub.2 C-CH.dbd.C(CH.sub.3)-CHO [I], wherein Hal signifies chlorine or bromine, comprises haloalkoxylating a 1-alkoxy-2-methyl-1,3-butadiene H.sub.2 C.dbd.CH-C (CH.sub.3).dbd.CH-OR.sup.1 [II], wherein R.sup.1 signifies C.sub.1-4 -alkyl, using a particular halogenating agent in a C.sub.1-4 -alkanol (R.sup.2 OH) and hydrolyzing the thus-obtained .gamma.-halotiglic aldehyde dialkyl acetal HalH.sub.2 C-CH.dbd.C(CH.sub.3)-CH (OR.sup.1)(OR.sup.2) [III] to the desired .gamma.-chloro- or .gamma.-bromotiglic aldehyde I. The halogenating agent used in this process is selected from an alkali metal hypochlorite, an alkali metal hypobromite, an alkaline earth metal hypochlorite, an alkaline earth metal hypobromite, tert.butyl hypochlorite, N-bromoacetamide, 1.3-dichloro-5,5-dimethylhydantoin and 1,3-dibromo-5,5-dimethylhydantoin. Further aspects of the present invention are the use of the thus manufactured .gamma.

Abstract: A process for the manufacture of polyene esters or polyene acids comprises reacting a polyene O,O-dialkylacetal of di(O,O-dialkylacetal) with a vinylketene acetal or analogue thereof in the presence of a Lewis acid, hydrolyzing the reaction mixture depending on the vinylketene acetal used, subsequently cleaving alcohol under strongly basic conditions from the polyene derivative produced at this stage and, where the desired ester or carboxy group is still not present, performing the respective conversion. Certain intermediates in this process form a further aspect of the invention. The final products are primarily carotenoids which can be used appropriately, e.g. as colorants and pigments for foodstuffs, animal products etc.

Abstract: To manufacture polyene aldehydes and polyene dialdehydes a polyene O,O-dialkyl acetal or polyene di(O,O-dialkyl acetal) is reacted with a 1-alkoxy-1,3-diene in the presence of a Lewis acid or a Bronsted acid. The reaction mixture is then hydrolyzed and the alcohol is cleaved under basic conditions from the polyene derivative produced by the reacting. Those intermediates in this process from which the alcohol is to be cleaved are novel. The final products are primarily carotenoids which can be used as colorants and pigments for foodstuffs, animal products, and the like.

Abstract: A novel process for the manufacture of a .gamma.-halotiglic aldehyde HalH.sub.2 C--CH.dbd.C(CH.sub.3)--CHO ?I!, wherein Hal signifies chlorine or bromine, comprises haloalkoxylating a 1-alkoxy-2-methyl-1,3-butadiene H.sub.2 C.dbd.CH--C(CH.sub.3).dbd.CH--OR.sup.1 ?II!, wherein R.sup.1 signifies C.sub.1-4 -alkyl, using a particular halogenating agent in a C.sub.1-4 -alkanol (R.sup.2 OH) and hydrolyzing the thus-obtained .gamma.-halotiglic aldehyde dialkyl acetal HalH.sub.2 C--CH.dbd.C(CH.sub.3)--CH(OR.sup.1)(OR.sup.2) ?III! to the desired .gamma.-chloro- or .gamma.-bromotiglic aldehyde I. The halogenating agent used in this process is selected from an alkali metal hypochlorite, an alkali metal hypobromite, an alkaline earth metal hypochlorite, an alkaline earth metal hypobromite, tert.butyl hypochlorite, N-bromoacetamide, 1.3-dichloro-5,5-dimethylhydantoin and 1,3-dibromo-5,5-dimethylhydantoin. Further aspects of the present invention are the use of the thus-manufactured .gamma.

Abstract: Novel processes and intermediates useful for the manufacture of the Wittig ester salts are disclosed. The Wittig ester salts are known as important C.sub.5 building blocks for the manufacture of various polyenecarboxylic acid esters in the field of carotenoid chemistry.

Abstract: A process for the manufacture of polyene esters or polyene acids comprises reacting a polyene O,O-dialkylacetal of di(O,O-dialkylacetal) with a vinylketene acetal or analogue thereof in the presence of a Lewis acid, hydrolyzing the reaction mixture depending on the vinylketene acetal used, subsequently cleaving alcohol under strongly basic conditions from the polyene derivative produced at this stage and, where the desired ester or carboxy group is still not present, performing the respective conversion. Certain intermediates in this process form a further aspect of the invention. The final products are primarily carotenoids which can be used appropriately, e.g. as colorants and pigments for foodstuffs, animal products etc.

Abstract: Novel processes and intermediates useful for the manufacture of the Wittig ester salts are disclosed. The Wittig ester salts are known as important C.sub.5 building blocks for the manufacture of various polyenecarboxylic acid esters in the field of carotenoid chemistry.

Abstract: A novel process for the manufacture of quinone derivatives is described.In this process a compound of the formula ##STR1## is reacted with a compound of the formula ##STR2## and the resulting compound of the formula ##STR3## is subjected to a retro-Diels-Alder reaction. The substituents R.sup.1, R.sup.2, R.sup.3 and R.sup.4 have the significance given in the description.

Abstract: A novel process for the manufacture of quinone derivatives which are suitable as intermediates for the manufacture of (2RS,4'R,8'R)-tocopherol is described. In this process a quinone of the formula ##STR1## is reacted with a phytyl derivative of the formula ##STR2## If desired, the thus-obtained compound of the formula ##STR3## is subsequently converted into the compound of the formula ##STR4## and, if desired, this compound is converted into the compound of the formula ##STR5## The compound of formula V is known and can be converted into (2RS,4'R,8'R)-tocopherol in a known manner.

Abstract: A novel process for the manufacture of quinone derivatives which are suitable as intermediates for the manufacture of (2RS,4'R,8'R)-tocopherol is described.

Abstract: A novel process for the manufacture of quinone derivatives is described.In this process a compound of the formula ##STR1## is reacted with a compound of the formula ##STR2## and the resulting compound of the formula ##STR3## is subjected to a retro-Diels-Alder reaction. The substituents R.sup.1, R.sup.2, R.sup.3 and R.sup.4 have the significance given in the description.