Patent GB-790930-A (GB)
Title: Improvements in the manufacture of acrylic acid and functional derivatives of acrylic acid
IPC: C07C51/14
Filed: 1955-07-14
Abstract: Acrylic acid and its functional derivatives are obtained by the catalytic reaction of acetylene with carbon monoxide and a compound with a reactive hydrogen atom at elevated temperature and pressure using as catalyst a complex compound of a nickel salt and a carboxylic acid amide formed by reacting 2 to 10 molecular proportions of the carboxylic acid amide with one molecular proportion of the nickel salt.  The compounds with a reactive hydrogen atom are water, an alcohol, a carboxylic acid, and an amine. Specified alcohols are methanol, ethanol, propanol, butanols and higher C5-C20 saturated alcohols, phenols, cyclohexanol, benzyl alcohol, and furfuryl alcohol.  The complex compounds are preferably derived from nickel halides, e.g. nickel bromide or iodide, and from amides of saturated aliphatic carboxylic acids or cyclic carboxylic acids, e.g. formamide, acetamide and their higher homologues and N-monoalkyl and N-dialkyl substituted derivatives, N-aryl and N-alkylaryl substituted amides, e.g. acetanilide and N-alkyl acetanilides, cyclohexane carboxylic acid N-dimethyl amide and benzoic acid N-methyl amide, and lactams of aminocarboxylic acids and their N-alkyl derivatives, e.g. pyrrolidone-2 and N-methyl pyrrolidone-2.  The complex compounds may be obtained by heating the nickel salt with the carboxylic acid amide at 40 DEG  to 160 DEG  C., preferably using from 4 to 10 molecular proportions of the amide per molecular proportion of the nickel salt, e.g. by the process of Specification 774,956.  Solutions of the complex compounds in the liquid initial materials may be used, specified solvents include hydrocarbons, ether and carboxylic acid amides.  The complex compounds may also be formed in situ from the nickel salt and carboxylic acid amide in the reaction mixture.  Specified reaction conditions are 100 DEG  C. to 250 DEG  C. under pressures of about 10 to 70 atmospheres and the process may be carried out discontinuously in an autoclave or continuously in reaction towers using a trickling, a continuous current or countercurrent technique.  Examples are given for the production of (1) butyl acrylate using preformed NiBr2.3N-methyl pyrrolidone-2 as catalyst; (2) ethyl acrylate by reacting a mixture of 1.2 parts by weight nickel bromide, 2.8 parts by weight N-methyl pyrrolidone-2 and 97 parts ethanol in countercurrent manner with acetylene and carbon monoxide; (3) ethyl acrylate using a catalyst as in (1) in the presence of tetrahydrofurane as solvent; (4) acrylic acid using the same catalyst as in (1) in the presence of tetrahydrofurane; (5) butyl acrylate using nickel bromide and pyrrolidone-2; (6) ethyl acrylate using nickel bromide and N,N-dimethylformamide in the presence of tetrahydrofurane; (7) ethyl acrylate using nickel bromide and N,N-dimethylacetamide or N-methyl acetanilide in the presence of tetrahydrofurane; (8) butyl acrylate using nickel bromide and molten acetamide or molten N,N-dimethyl benzamide; (9) phenyl acrylate using NiBr2.3N-methyl pyrrolidone-2 in the presence of tetrahydrofurane; (10) 2-ethyl hexyl acrylate using NiBr2.3N-methyl pyrrolidone-2; (11) methyl acrylate using NiBr2 and N-dimethyl formamide; (12) and (13) benzyl acrylate and cyclohexyl acrylate respectively using NiBr2.3N-methyl pyrrolidone-2.  Specification 750,538 also is referred to.