Process for the production of alpha-6-deoxytetracyclines and hydrogenation catalyst useful therein
AssigneeRanbaxy Laboratories Limited
InventorsJagmohan Khanna, Kiran Bala, Inder P. S. Grover
Life of this patent
Estimating the term…
Abstract
A coordination compound useful as a hydrogenation catalyst, having the formula: ##STR1## wherein Ph is phenyl; R is hydrogen or C.sub.1 -C.sub.4 alkyl; and X is chloro, bromo or iodo. This compound is particularly useful as a homogeneous hydrogenation catalyst in the production of alpha-6-deoxytetracyclines, particularly the antibiotic doxycycline. The desired alpha-6-deoxy product is produced in high yields and stereospecificities, the process requiring the use of minimal quantities of rhodium metal in the hydrogenation catalyst per mole of the 6-methylenetetracycline hydrogenated.
Claims12
In a process for the preparation of an alpha-6-deoxytetracycline by the hydrogenation of a substrate selected from the group consisting of an 11a-chloro-6-deoxy-6-demethyl-6-methylenetetracycline, a 6-deoxy-6-demethyl-6-methylenetetracycline and salts thereof, the improvement comprising conducting the hydrogenation in the presence of a homogeneous hydrogenation catalyst comprising ##STR5## wherein ph is phenyl
- R is hydrogen or C.sub.1 -C.sub.4 alkyl;
- and
- X is chloro, bromo, or iodo.
Dependencies are inferred from the claim text.