Rhodium hydrogenation catalysts.

摘要

The present invention refers to complexes prepared by reacting rhodium trinitrate with a suitable hydrazine and a suitable tertiary phosphine, more specifically to the compounds di( mu -hydrazine-N<1>:N<2>)-bis[bis(triphenylphosphine)rhodium (I) ]dinitrate and mu -3-carbopentazane-N<1>,N<4>:N<2>,N<5>-bis[bis(triphenylphosphine)rhodium (I)]dinitrate, which are homogenous hydrogenation catalysts and their application in the hydrogenation of the exocyclic methylene group of acid addition salts of 6-demethyl-6-deoxy-6-methylene-5-hydroxytetracycline (methacycline) to prepare alpha -6-deoxy-5-hydroxy-tetracycline (doxycycline).