Process for catalytically reducing carbonyl compounds

Abstract

Abstract Catalytic reduction of carbonyl compounds by transfer of hydrogen from alcohols to aliphatic, alicyclic, aromatic, homo- and heterocyclic ketones or aldehydes, catalyzed by rhodium or iridium complexes, characterized in that a primary or secondary alcohol of formula (I) or a glycol: ##STR1## is reacted with a ketonic compound of formula (II): ##STR2## in which R and R' and, respectively, R" and R'", optionally linked with each other according to homo- or heterocycles, indifferently represent a hydrogen atom or a hydrocarbyl group having up to 30 atoms of carbon, also substituted, provided that at least one of symbols R" and/or R'" is different respectively from R and/or R', in the presence of a complex catalyst of rhodium or of iridium selected from those having formulas (III) and (IV): ##STR3## wherein: M is selected from Rh and Ir; Chel is a chelating bidentate nitrogenous compound; L-L is a molecule of a preferably non-conjugated diolefin or two molecules of a monoolefin; X - is an anion selected from amongst Cl - , Br - , J - , PF 6 - , BF 4 - , C10 4 - , B(C 6 H 5 ) 4 - ; Y is a halogen, preferably it is Cl or Br; n is an integer from 0 to 3; and of a compound selected from amongst mineral alkalis and tertiary amines at a temperature ranging from about 20° C. to the boiling temperature of the reaction mass, preferably in an inert atmosphere. The products obtained are employed as intermediates for organic syntheses in the field of fine chemicals. Some terms of the classes of catalysts herein described are to be considered as new in themselves.

Inventors

• 👤 Giovanni Mestroni
• 👤 Grazia Zassinovich
• 👤 Annamaria Camus

Bibliographic Details