Process for simultaneous recovery of precious metals and tertiary phosphine from spent catalysts using tellurium

Process for the preparation of a rhodium complex

Rhodium hydrogenation catalysts particularly for stereoselective hydrogenation of methacycline to doxycycline

Rhodium-containing hydrogenation catalysts for the conversion of methacycline to doxycycline

9.alpha.-Fluoro or 9.alpha.-chloro corticosteroid esters