3,056,839 United States Patent 0 Patented Oct. 2, 1962

1 2 outlet at 140° C., the temperature then being raised 3,056,839 gradually to 170° C. A steady stream of carbon dioxide PRODUCTION OF UNSATURATED KETONES was evolved from the pyrolysis of the methylbutenyl Richard Norman Lacey, Hull, England, assignor to The acetoacetate, leaving methylheptenone in the reactor. Distillers Company Limited, Edinburgh, Scotland, a The nature and weight of the aluminium tri-carboxylate, British company the temperature to which the mixture of methylbutenyl No Drawing. Filed Dec. 17, 1959, Ser. No. 860,082 acetoacetate and the aluminium tri-carboxylate was heated Claims priority, application Great Britain Jan. 14, 1959 and the yield of methyl heptenone produced based on the 4 Claims. (Cl. 260-595) methylbutenyl acetoacetate, are shown in the following 10 table. In the table is also included, as a comparison, the The present invention relates to the production of yield of methylheptenone obtained under the same condi organic compounds and in particular to the production of tions except that no aluminium tri-carboxylate was unsaturated ketones. According to the present invention, the process of present. producing an unsaturated ketone representable by the formula 15 Weight of Yield of Exam- Weight of methyl- methyl BJ~—C=C]E[.C§H2.CHLCO.Ra ple Catalyst catalyst heptenone heptenone, (grams) produced percent R2 (grams) comprises contacting an allyl acetoacetate representable by the formula 20 None ______215 63.5 R3 1 ______Aluminium triacetate ______8.8 251 74 2 ______.._do ______13.2 251 74 R1—J>—0.C0.(JH2O0Ra 3 _____ -_ Basic aluminium triacetate 8.3 253 74.5 (CHa.COO)4.OAlz.4H2O. H=0Hi 4 ______Basic aluminium triacetate 12.3 245 72.1 (CH3.000)4.0A1Z.4H20. with an aluminium tri-carboxylate, wherein R1 and R2 5 ______- Aluminium tristearate ______38 244 72.1 are alkyl groups or hydrogen atoms and R3 is a lower 25 alkyl group. The allyl acetoacetate may be contacted with the alu I claim: minium tri-carboxylate with advantage at an elevated 1. A process of producing an unsaturated ketone having temperature, preferably at a temperature in the range from the formula 100° to 300° C. The temperature used in any particular R1~C:CH.OH2.OHLGO.R3 embodiment of the invention depends on the nature of {a the allyl acetoacetate heated; if, for instance, the allyl which comprises contacting at a temperature in the range acetoacetate is methylbutenyl acetoacetate, it may be heat of 100° to 300° C. an allyl acetoacetate having the ed at a temperature from 110° to 170° C., preferably from 35 formula 140° to 170° C. The allyl acetoacetate is conveniently R2 heated with the aluminium tri-carboxylate in an apparatus which enables a steady stream of carbon dioxide to be R1—(‘J—-O.OO.OHZCO.R3 evolved and removed. H=CH2 The aluminium tri-carboxylate used in the process of with an aluminium tri-carboxylate derived from a fatty the invention may be, for example, aluminium triacetate, acid having 2 to 18 carbon atoms in the fatty acid basic aluminium triacetate (CH3.COO)4.OAl2.4H2O, molecule, wherein R1 and R2 are selected from the group aluminium tributyrate, aluminium trioctanoate, aluminium consisting of alkyl groups and hydrogen atoms, and R3 trilaurate, aluminium tripalmitate or aluminium tristea rate. Aluminium tri-carboxylates containing more than is a lower alkyl group. 45 2. A process claimed in claim 1 wherein the aluminium one carboxylic acid residue, such as aluminium diacetate compound is aluminium triacetate. monopropionate or aluminium acetate propionate butyrate 3. A process claimed in claim 1 wherein the aluminium are also included in the invention. Furthermore, one or compound is basic aluminium triacetate. more of the fatty acid residues in the aluminium tri 4. A process claimed in claim 1 wherein the aluminium carboxylate may be unsaturated, for example as in alu compound is aluminium tristearate. minium trioleate. 50 The following examples further illustrate the invention. References Cited in the ?le of this patent Examples 1 to 5 UNITED STATES PATENTS A series of 500 gram samples of methylbutenyl aceto acetate of 94% purity were heated with an aluminium tri 55 2,795,617 Kimel et al ______June 11, 1957 carboxylate in a reactor ?tted with a stirrer and a gas 2,839,579 Kimel et al. ______June 17, 1958