摘要:
The manufacture of optically active bifunctional compounds of the general formula ##STR1## wherein R represents protected hydroxymethyl, protected formyl or alkoxycarbonyl and R.sup.1 represents a group of the formula ##STR2## or --CH.sub.2 --CH.dbd.NR.sup.2 in which R.sup.2 and R.sup.3 represent lower alkyl or cycloalkyl or R.sup.2 and R.sup.3 together with the nitrogen atom represent a heterocyclic ring,by isomerizing compounds of the general formula ##STR3## wherein R, R.sup.2 and R.sup.3 have the above significance and R.sup.3 can additionally signify hydrogen,is described.The compounds of formula I are potential intermediates in the manufacture of, inter alia, natural vitamin E and natural vitamin K.sub.1.
摘要:
The manufacture of optically active bifunctional compounds of the general formula ##STR1## wherein R represents protected hydroxymethyl, protected formyl or alkoxycarbonyl and R.sup.1 represents a group of the formula ##STR2## in which R.sup.2 and R.sup.3 represents lower alkyl or cycloalkyl or R.sup.2 and R.sup.3 together with the nitrogen atom represent a heterocyclic ring, by isomerizing compounds of the general formula ##STR3## wherein R, R.sup.2 and R.sup.3 have the above significance and R.sup.3 can additionally signify hydrogen, is described.The compounds of formula I are potential intermediates in the manufacture of, interalia, natural vitamin E and natural vitamin K.sub.1.
摘要:
Novel chiral phosphorus compounds of the general formula ##STR1## wherein R signifies substituted or unsubstituted phenyl, R.sup.1 and R.sup.2, which can be the same or different, signify hydrogen, lower alkyl, lower alkoxy, di-lower alkylamino or protected hydroxymethyl or R.sup.1 and R.sup.2 together signify the group ##STR2## in which m represents a number 3 to 5, R.sup.4 represents lower alkyl, substituted or unsubstituted phenyl or benzyl and R.sup.5 represents lower alkyl or both R.sup.5 's together represent lower alkylene, R.sup.3 signifies methyl, lower alkoxy, di-lower alkylamino or fluorine and n signifies the number 0, 1, 2 or 3, are described.The compounds of formula I are useful in the form of complexes with a metal of Group VIII as catalysts for asymmetric hydrogenations and enantioselective hydrogen displacements in prochiral allylic systems.
摘要:
Novel Isoprene Derivatives which have mucosa-protective and gastric acid secretion-inhibiting properties and are useful for combatting ulcers both by treating and as a prophylaxis against gastric and/or duodenal ulcers.
摘要:
The invention relates to a multiple insertion head for mounting components (300) onto substrates, said insertion head comprising a carrier (200) which is arranged in such a way that it can rotate about a rotational axis (D) and is provided with a plurality of receiving tools (210) that are arranged in such a way that they can be displaced in a mounting direction at an angle to the rotational axis (D), said receiving tools being used to receive the components (300). Each receiving tool (210) is provided with at least one active drive and/or sensor, ensuring that the components (300) are rapidly positioned with the highest precision.
摘要:
A process for the manufacture of bisphosphine oxide compounds and bisphosphonates as intermediates for the production of bisphosphine ligands, in which in a single step processa) a phosphine oxide compound is reacted in an organic solvent at -70.degree. C. to 20.degree. C. with 0.5-3 eq. of a lithium or magnesium amide compound,b) 0.5-3 eq. of oxidatively-acting metal salt or metal salt complex are added to the suspension obtained in stage a) in a temperature range of -70.degree. C. to 20.degree. C., with a racemate of a bisphosphine oxide compound being obtained;c) a racemate cleavage is carried out if desired; andd) the bisphosphonates obtained in stage b) or c) are converted into bisphosphine oxides.
摘要:
Novel, racemic and optically active phosphorus compounds of the formula ##STR1## wherein R signifies lower alkyl or lower alkoxy and R.sup.1 represents lower alkyl, cycloalkyl or substituted phenyl, are described.The compounds of formula I are useful in the form of complexes with a metal of Group VIII as catalysts for asymmetric hydrogenations and for enantioselective hydrogen displacements in prochiral allylic systems.
摘要:
Novel, racemic and optically active phosphorus compounds of the formula ##STR1## wherein R signifies lower alkyl, lower alkoxy or protected hydroxy, R.sup.1 signifies lower alkoxy, phenoxy, benzyloxy, chlorine or bromine, R.sup.2 stands for lower alkyl or lower alkoxy and n represents the number 0, 1 or 2, are described. These compounds are valuable intermediates in the manufacture of not only known, but also novel diphosphine ligands.
摘要:
A process for the manufacture of 3-phytyl-2,5,6-trimethylhydroquinone-1-acetate, and optionally therefrom tocopheryl acetate, comprises either C-alkylating 2,3,6-trimethylhydroquinone-1-acetate with isophytol or phytol in the presence of a sulphur(VI) containing catalyst of the formula R1SO2OH, wherein R1 signifies hydroxy, halogen, lower alkyl, halogenated lower alkyl or aryl, in an aprotic organic solvent, or O-alkylating 2,3,6-trimethylhydroquinone-1-acetate with a phytyl halide in a polar aprotic organic solvent in the presence of a base, and subjecting the so-obtained 4-O-phytyl-2,3,6-trimethylhydro-quinone-1-acetate to a rearrangement reaction, and in each case optionally submitting the so-obtained 3-phytyl-2,5,6-trimethylhydroquinone-1-acetate to a ring closure reaction to produce tocopheryl acetate. The invention also includes the novel compound 3-phytyl-2,5,6-trimethylhydroquinone-1-acetate and certain stereoisomers thereof, and also the further novel compound 4-hydroxy-2,3,6-trimethyl-5-[3-(4,8,12-trimethyltridecyl)-but-3-enyl]phenyl acetate which itself is one of several isomers of 3-phytyl-2,5,6-trimethylhydroquinone-1-acetate formed by isomerization under the influence of heating, e.g. during its distillation as part of the isolation and purification procedure following its manufacture as indicated above. (All-rac)-α-tocopherol, which may be derived from its acetate, is known to be the most active industrially important member of the vitamin E group.