Hoffmann-la Roche Inc.

Hans-Jurgen Hansen

Rudolf Schmid

Max Schmid

Karlheinz Pfoertner

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.

Process for the manufacture of optically active compounds

Compounds of the formula ##STR1## wherein R.sup.1 -R.sup.4 is hydrogen or chlorine, R.sup.5 is --COOMe or --SO.sub.3 Me, Me is an alkali metal cation and X is oxygen, sulfur or selenium, photosensitizers for the conversion of tachysterol into previtamin D are described. The tachysterol content in mixtures of previtamin D and tachysterol can be greatly reduced by UV-irradiation in the presence of such photosensitizers.

Compounds of o-(6-hydroxy-3-oxo-3H-thio(seleno)xanthen-9-yl)benzene

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.

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.

Phosphorus compounds

Compounds of the formula ##STR1## wherein R.sup.1 -R.sup.4 is hydrogen or chlorine, R.sup.5 is --COOMe or --SO.sub.3 Me, Me is an alkali metal cation and X is oxygen, sulfur or selenium, photosensitizers for the conversion of tachysterol into previtamin D are described. The tachysterol content in mixtures of previtamin D and tachysterol can be greatly reduced by visible light irradiation in the presence of such photosensitizers.

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Riehen, Switzerland

Hans-Jurgen Hansen