Rhodium-containing catalysts and their application
A catalyst for hydrogenating tetracycline intermediates was prepd. by treating a Rh phosphine complex with a hydrazine. Thus (Ph3P)3RhCl was treated with N2H4 to give a catalyst contg. 16.95% Rh which was used together with PPh3 to hydrogenate I (RR1 = CH2) to give I (R = Me, R1 = H) free from epimer.