Process for the manufacture of enol derivatives

Process for the manufacture of a 7.beta.-amino-3-cephem-3-ol-4-carboxylic acid compound of the formula ##STR9## wherein R.sub.1.sup.a represents an acyl group of the formula ##STR10## wherein R.sup.I represents hydrogen or cycloalkyl with 5-7 ring carbon atoms which is substituted in the 1-position, by amino, protected amino, sulphoamino or sulphoamino in the form of a salt, or R.sup.I represents phenyl, naphthyl or tetrahydronaphthyl, or phenyl, naphthyl or tetrahydronaphthyl substituted by hydroxyl, protected hydroxyl, and/or by halogen, a 4-isoxazolyl group or a 4-isoxazolyl group substituted by lower alkyl, and/or phenyl, which can in turn carry halogen, or R.sup.I represents an amino group which is N-substituted by lower alkyl or halogen-substituted lower alkyl, or R.sub.1 represents an acyl group of the formula ##STR11## wherein R.sup.I represents lower alkyl, halogene-lower alkyl, phenyloxy-lower alkyl, hydroxyphenyloxy-lower alkyl, protected hydroxyphenyloxy-lower alkyl, halogeno-phenyloxy-lower alkyl, or lower alkyl substituted by amino and/or carboxyl, wherein amino is free or protected and carboxyl is free or protected, or R.sup.I represents lower alkenyl, phenyl, hydroxyphenyl, protected hydroxyphenyl, halogenophenyl, hydroxy-halogeno-phenyl, protected hydroxy-halogenophenyl, amino-lower alkyl-phenyl, protected amino-lower alkyl-phenyl, phenyloxyphenyl, or R.sup.I represents pyridyl, pyridinium, thienyl, furyl, imidazolyl or tetrazolyl, or these heterocyclic groups substituted by lower alkyl, amino, protected amino, aminomethyl or protected aminomethyl, or R.sup.I represents lower alkoxy, phenyloxy, hydroxyphenyloxy, protected hydroxyphenyloxy, halogenophenyloxy, lower alkylthio, lower alkenylthio, phenylthio, pyridylthio, 2-imidazolylthio, 1,2,4-triazol-3-ylthio, 1,3,4-triazol-2-ylthio, 1,2,4-thiadiazol-3-ylthio, 1,3,4-thiadiazol-2-ylthio, or 5-tetrazolythio, and these heterocyclylthio groups, substituted by lower alkyl, or R.sup.I represents halogeno, lower alkoxycarbonyl, cyano, carbamoyl, N-lower alkyl-carbamoyl, N-phenylcarbamoyl, lower alkanoyl, benzoyl, or azido, or R.sub.1.sup.a represents an acyl group of the formula ##STR12## wherein R.sup.I represents lower alkyl, phenyl, hydroxyphenyl, protected hydroxyphenyl, halogenophenyl, hydroxy-halogenophenyl, protected hydroxy-halogeno-phenyl, furyl, thienyl, or isothiazolyl, and also represents 1,4-cyclohexadienyl, and R.sup.II represents amino, protected amino, guanidinocarbonylamino, sulphoamino, sulphoamino in salt-form, azido, carboxyl, carboxyl in salt-form, protected carboxyl, cyano, sulpho, hydroxyl, protected hydroxyl, O-lower alkyl-phosphono, O,O'-di-lower alkyl-phosphono or halogeno or R.sub.1.sup.a represents a group of the formula ##STR13## wherein R.sup.I and R.sup.II each represent halogen, or lower alkoxycarbonyl, or R.sub.1.sup.a represents a group of the formula ##STR14## wherein R.sup.I represents phenyl, hydroxyphenyl, protected hydrophenyl, hydroxy-halogeno-phenyl, protected hydrohalogenophenyl, furyl, thienyl, isothiazolyl, or 1,4-cyclohexadienyl, and R.sup.II represents aminomethyl or protected aminomethyl or R.sub.1.sup.a represents a group of the formula ##STR15## wherein each of the groups R.sup.I, R.sup.II and R.sup.III represents lower alkyl, and R.sub.1.sup.b represents hydrogen, or R.sub.1.sup.a and R.sub.1.sup.b together represents 1-oxo-3-aza-1,4-butylen, such group substituted in the 2-position by a group R.sup.I as defined under formula (A.sub.3) an such group substituted in the 4-position by lower alkyl, R.sub.2 represents a group R.sub.2.sup.A which together with the carbonyl grouping --C(.dbd.O)-- forms a protected carboxyl group, a 1-oxide thereof or a metal or an ammonium salt of such a compound having a sulpho or a carboxy group or an acid addition salt of such a compound having a basic amino group, characterised in that in a compound of the formula ##STR16## wherein the dotted line indicates a double bond in the 2,3- or in the 3,4-position, R.sub.1.sup.a, R.sub.1.sup.b and R.sub.2 have the above mentioned meanings, and R.sub.3.sup.o is a 2-oxa-aliphatic, 2-oxa-cycloaliphatic, 2-thialiphatic, or 2-thia-cycloaliphatic hydrocarbon radical, a silyl or stannyl group substituted by lower alkyl, halogeno lower alkyl, cycloalkyl, phenyl, phenyl-lower alkyl, lower alkoxy or halogen, or an alpha-phenyl-lower alkyl group having one or two phenyl groups, wherein phenyl may be substituted by halogen or lower alkoxy, or in a 1-oxide thereof or a metal or an ammonium salt of such a compound having a sulpho or a carboxy group or an acid addition salt of such a compound having a basic amino group, the group R.sub.3.sup.o is split off and replaced by hydrogen by treatment with hydrogen in the presence of a catalyst, with water, an alcohol, or an organic or inorganic acid.