The present invention provides a process for preparation of {(2E,4E,6E,8E)-9-(4-methoxy-2,3,6-trimethyl)phenyl-3,7-dimethyl-nona-2,4,6,8}tetraenoate, an acitretin intermediate of formula (VI) with trans isomer≧97%, comprising of reacting 3-formyl-crotonic acid butyl ester of formula (V), substantially free of impurities, with 5-(4-methoxy-2,3,6-trimethylphenyl)-3-methyl-penta-2,4-diene-1-triphenyl phosphonium bromide of formula (IV) and isolating resultant compound of formula (VI), treating the filtrate with iodine for isomerization of the undesired cis intermediate and finally obtaining acitretin (I), with desired trans isomer≧97%.

This invention relates to methods for the synthesis of spiro[2.5]octane-5, 7-dione and spiro[3.5]nonane-6, 8-dione which are useful as intermediates in the manufacture of pharmaceutically active ingredients.

This invention relates to methods for the synthesis of spiro[2.5]octane-5, 7-dione and spiro[3.5]nonane-6, 8-dione which are useful as intermediates in the manufacture of pharmaceutically active ingredients.

This invention relates to methods for the synthesis of spiro[2.5]octane-5, 7-dione and spiro[3.5]nonane-6, 8-dione which are useful as intermediates in the manufacture of pharmaceutically active ingredients.

A method of implementing organic synthesis reactions uses a composition containing a metal catalyst originating from a calcined plant. The plants can be from the Brassicaceae, Sapotaceae and Convolvulaceae family, and the metal catalyst contains metal in the M(II) form such as zinc, nickel, manganese, lead, cadmium, calcium, magnesium or copper. Examples of the organic synthesis reactions include halogenations, electrophilic reactions, cycloadditions, transesterification reactions and coupling reactions, among others.

A method of implementing organic synthesis reactions uses a composition containing a metal catalyst originating from a calcined plant. The plants can be from the Brassicaceae, Sapotaceae and Convolvulaceae family, and the metal catalyst contains metal in the M(II) form such as zinc, nickel, manganese, lead, cadmium, calcium, magnesium or copper. Examples of the organic synthesis reactions include halogenations, electrophilic reactions, cycloadditions, transesterification reactions and coupling reactions, among others.

A process of converting a carbon-carbon multiple bond to a cyclopropane ring, comprising the addition of a N-alkyl-N-nitroso compound to a mixture of alkene precursor, aqueous base and Pd(II)-catalyst, with the N-alkyl-N-nitroso compound obtained directly from an alkyl amine derivative, NaNO.sub.2 and an acid via phase separation of the N-alkyl-N-nitroso compound from the aqueous phase.

A process of converting a carbon-carbon multiple bond to a cyclopropane ring, comprising the addition of a N-alkyl-N-nitroso compound to a mixture of alkene precursor, aqueous base and Pd(II)-catalyst, with the N-alkyl-N-nitroso compound obtained directly from an alkyl amine derivative, NaNO.sub.2 and an acid via phase separation of the N-alkyl-N-nitroso compound from the aqueous phase.

A process of converting a carbon-carbon multiple bond to a cyclopropane ring, comprising the addition of a N-alkyl-N-nitroso compound to a mixture of alkene precursor, aqueous base and Pd(II)-catalyst, with the N-alkyl-N-nitroso compound obtained directly from an alkyl amine derivative, NaNO.sub.2 and an acid via phase separation of the N-alkyl-N-nitroso compound from the aqueous phase.

[6,6]-Phenyl C.sub.71 butyric acid derivatives (C.sub.70-PCBR.sub.3) having a selectivity of greater than 95 wt % of the α-isomer are provided by reacting fullerene C.sub.70 with a dialkyl sulfonium tetrafluoroborate having the formula:

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