Abstract:
The present invention relates to a process for the preparation of the compound of formula (7) which process comprises the hydrogenation of the compound of formula (4) using bis[chloro-1,5-cyclooctadiene-iridium], (S)-i -dicyclohexylphosphino- 2-[(S)-α-(dimethylamino)-2-(dicyclohexylphosphino)benzyl]-ferrocene as a catalyst.
Abstract:
R-Hydroxynitrillyasen aus der Familie Rosaceae mit einer verbesserten Substratak zeptanz und erhöhter Stabilität, bei weichen im aktiven Zentrum der R Hydroxynitrillyasen entweder a) ein Alaninrest durch Glycin, Valin, Leucin, Isoleucin oder Phenylalanin oder b) ein Phenylalaninrest durch Alanin, Glycin Valin, Leucin oder Isoleucin oder c) ein Leucinrest durch Alanin, Glycin, Valin, Isoleucin oder Phenylalanin oder d) ein Isoleucinrest durch Alanin, Glycin, Valin, Leucin oder Phenylalanin substituiert ist und deren Verwendung zur Herstellung von enantiomerenreinen R- oder S-Cyanhydrinen.
Abstract:
An improved process for preparing o-chloromethylphenylglyoxylic esters of the formula (I) which comprises converting a compound of the formula (II) by reaction with magnesium into the corresponding Grignard reagent which is then reacted with a compound of the formula (III) to give the compound of the formula (IV) which is then cleaved by reaction with a chloroformic ester of the formula ClCOOR4 or by reaction with phosgene to give the compound of the formula (I), followed by the isolation of the compound of the formula (I), and also an improved process for preparing (E)-2-(2-chloromethylphenyl)- 2-alkoximinoacetic esters of the formula (VII) and intermediates for their preparation.
Abstract:
A method for preparing enantiomerically enriched 2-alkyl-5-halopent-4-enecarboxylic acids or their esters of the formula (II) in which R is a C 1 -C 6 -alkyl radical, A is equal to H, R 1 , where R 1 may be C 1 -C 4 -alkyl, or R 2 , where R 2 is an alkyl group but is not equal to R 1 , and X is chlorine, bromine or iodine, by racemate resolution of a mixture of enantiomers of a 2-alkyl-5-halopent-4-enecarboxylic ester of the formula (I) in which R, R 1 and X are as defined above, by means of a polypeptide having esterase activity or of a recombinant protein having esterase activity, which have an amino acid sequence as shown in SEQ ID No. 1 or is at least 80 % identical thereto, and polypeptide and recombinant esterase which has the amino acid sequence SEQ. ID. No. 1, and the use thereof .
Abstract:
A process for preparing enantiomerically enriched E-(2S) - and (2R)-alkyl-5-halopent-4-enecarboxylic acids or their esters of the formula (Ia) or (Ib) in which R is a C 1 -C 6 -alkyl radical, A is H, R 1 , where R 1 can be C 1 -C 4 -alkyl, or R 2 , where R 2 is an alkyl group but is not identical to R 1 , and X is chlorine, bromine or iodine, in which an enantiomeric mixture of a 2-alkyl-5-halopent-4-enecarboxylic ester of the formula (II) in which R, R 1 and X are defined as above, is reacted with a stereoselective hydrolase, which is obtained from microorganisms or plants, in the presence of water or an alcohol of the formula R 2 OH, where R 2 is an alkyl group which is not identical to R 1 , as nucleophile.
Abstract:
A process for preparing N-acetylaminoacetophenones of the formula (I) where R1 is a C 1 -C 8 -alkyl radical, C 1 -C 6 -alkylsulfinyl, C 1 -C 6 -alkylsulfonyl, C 1 -C 4 -alkoxy-C 1 -C 4 -alkyl, halocycloalkyl, formyl-C 1 -C 3 -alkyl or -C(=0)C(=0)R4, R2 is C 1 -C 4 -alkyl, C 1 -C 6 -alkylsulfinyl, C 1 -C 6 -alkylsulfonyl, C 1 -C 4 -alkoxy-C 1 -C 4 -alkyl, halocycloalkyl, formyl-C 1 -C 3 -alkyl, R3 is H, fluorine, chlorine, C 1 -C 4 -alkyl or trifluoromethyl and R4 is hydrogen, C 1 -C 8 -alkyl, C 1 -C 8 -alkoxy, C 3 -C 8 -cycloalkyl, wherein an indole of the formula (II) where R2 and R3 are as defined above and R5 is H or a C 1 -C 4 -alkyl radical, C 1 -C 8 -alkylsulfinyl, C 1 -C 6 -alkylsulfonyl, C 1 -C 4 -alkoxy- C 1 -C 4 -alkyl, halocycloalkyl, formyl- C 1 -C 3 -alkyl, C(=0)C(=0)R4, where R4 is as defined above, is reacted with ozone in a suitable solvent from the group consisting of C 1 -C 6 -alcohols, nitriles, C 1 -C 4 -carboxylic acids or an anhydride thereof, C 1 -C 6 -alkyl acetates, chlorinated hydrocarbons, water and mixtures thereof and the peroxide solution obtained in this way is reduced and the desired N-acetylaminoacetophenone of the formula (I) is isolated, and also, if desired, conversion of the compound of the formula (I) into a compound of the formula (III) where R2 and R3 are as defined above.
Abstract:
Verbessertes Verfahren zur Herstellung von N-substituierten Amiden der formel RCONHR1 (I) in der R einen gegebenenfalls ein- oder mehrfach substituierten C 1 -C 20 -Alkyl-, C 5 -C 20 -Aryl- oder C 5 -C 20 -Heterocyclusrest und R1 einen gegebenenfalls ein- oder mehrfach substituierten C 1 -C 20 -Alkyl-oder C 5 -C 20 -Arylrest bedeuten aus den korrespondierenden Nitriten der Formel RCN (II) in der R1 wie oben definiert ist, bei welchem ein Nitrit der Formel (II) in Polyphosphorsäure mit einem Alkohol der Formel R10H (III) in der R1 wie oben definiert ist, in Gegenwart einer Verbindung aus der Gruppe Phosphorpentoxid, Phosphoroxychlorid, Sulfurylchlorid, Dialkylcarbonat und Dialkylsulfat bei einer Temperatur zwischen 80 und 190°C zu dem entsprechenden N-substituierten Amid umgesetzt wird.
Abstract:
The present invention relates to a process for the preparation of the compound of formula (7) which process comprises the hydrogenation of the compound of formula (4) using bis[chloro-1,5-cyclooctadiene-iridium], (S)-i -dicyclohexylphosphino- 2-[(S)-a-(dimethylamino)-2-(dicyclohexylphosphino)benzyl]-ferrocene as a catalyst.
Abstract:
A process for preparing 3,4-disubstituted phenylacetic acids of the formula (I) in which X is fluorine, chlorine, bromine or iodine and R is C 1 -C 4 -alkylthio, C 1 -C 4 -alkylsulfonyl or C 1 -C 4 -alkylsulfoxide, starting from a 2-halo-C 1 -C 4 -alkylthiobenzene of the formula (II) in which X is as defined above and R1 is C 1 -C 4 -alkylthio.