GB628659A - Improvements in and relating to the synthesis of organic nitrogen compounds - Google Patents

Abstract

Organic nitrogen compounds such as amides, nitriles and lactams, are prepared by reacting at a pressure above 50 atmos., carbon monoxide, and ammonia or an amine NHR2, where R is hydrogen or an organic radical, with a compound having at least one non-benzenoid double bond between carbon atoms, in the presence of a hydrogenating catalyst at elevated temperature. A single compound may constitute both the amine and the unsaturated compound. The unsaturated compound may be an olefin, diolefin, cyclo-olefin, cracked petroleum fraction, diene polymer, ester, ether, carboxylic acid, nitrile, amide, amine, aldehyde or ketone, examples being given. The groups R may be the same or different and include alkyl, cycloalkyl, alkenyl, cycloalkenyl, aryl, aralkyl, or derivatives thereof containing, for example, hydroxy, amino or alkoxy substituents. Temperatures are generally about 150-350 DEG C., and pressures may be up to 2000-3000 atm. or more. Suitable catalysts are Co, Ni, Ru, Cu, their compounds and alloys, if desired with supports or promoters. Cobalt carbonyl is preferred and may be used in an amount of a few tenths per cent of the reaction mixture, preferably in an inert solvent. Metallic cobalt or nickel, cobalt chromite, cobalt-substituted amides, and cobalt carboxylates are also suitable. Liquid or vapour phase reaction in reactors lined with silver or of material yielding cobalt carbonyl may be used. Amides are the principal products but, at higher temperatures, nitrile formation may be appreciable. Unsaturated esters may yield diamides or imides. In examples: (1) and (2) reduced sintered cobalt oxide, diethyl ether, dimethylamine, ethylene, and carbon monoxide under pressure are heated to yield N,N-dimethyl propionamide; (3) and (4) ammonia is used with either ether or benzene as solvent giving propionamide; (5) the only catalyst is a minute amount of cobalt adhering to the silver-lined reactor; (6) crude cobalt-containing propionamide prepared as in (3) is catalyst, the products being propionamide and propionitrile; (7) propylene and ammonia with carbon monoxide give n-butyramide and di-isopropyl ketone; (8) butene-1 similarly yields n-valeramide; (9) cobalt carbonyl is catalyst for preparation of cobalt-containing crude propionamide from ethylene and ammonia; (10) the N,N-dimethyl amide of 3 - cyclohexene - 1 - carboxylic acid, prepared from the methyl ester and dimethylamine, with dimethylamine and carbon monoxide, yields the N,N,N1,N1-tetramethyl diamide of cyclohexane dicarboxylic acids; (11) cobalt propionate, propionamide, ammonia, ethylene, and carbon monoxide are heated to yield propionamide and a crude cobalt-containing residue which is recycled; (12) using vinylcyclohexene and dimethylamine, an N,N - dimethylamide C11H19ON is formed together with dimethylformamide, which can be recycled to yield further dimethylamide; (13) alkylamine and carbon monoxide yield g -butyrolactam; (14) and (15) propionamide and diethyl ketone are formed using ammonia and ethylene, and a nickel or copper propionate catalyst.