The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 29, 1985
Filed:
Mar. 14, 1983
George E Lee, Somerville, NJ (US);
Thomas B Lee, Whitehouse Station, NJ (US);
Hoechst-Roussel Pharmaceuticals Inc., Somerville, NJ (US);
Abstract
A stereoselective reduction of 2- or 3-substituted 4-piperidones of the formula ##STR1## where R.sub.1 is hydrogen, loweralkyl or benzyl and R.sub.2 is methyl or ethyl, to the di-equatorial isomer of the corresponding 4-piperidinol is described. Said reduction is conducted by use of sodium borohydride in a protic solvent medium at a temperature substantially lower than ambient temperature in the presence of an effective amount of an inorganic acid. Under favorable reaction conditions, the stereoselectivity of the reduction is so high that simple crystallization of the reaction product affords the pure isomer in a commercially acceptable and advantageous process.