Patent ID: 6506942
Filing Date: 2003-01-14
Classification: C07B,C07C

Abstract:
A process for the preparation of a carbonyl compound of the general formula (1)R1R2C&boxH;Oâ€ƒâ€ƒ(1), comprising cleaving a &bgr;-hydroxycarboxylic acid or its salt of the general formula (2)R1R2C(OH)â€”CR3R4â€”COOMâ€ƒâ€ƒ(2), in the presence of a BrÃ¶nstedt base which is selected from the group consisting of hydroxides, alkanolates, oxides, amides, and hydrides of the alkali metals and alkaline earth metals, and mixtures of these BrÃ¶nstedt bases, and in the presence of a hydroxyl-free solvent, whereR1 denotes an optionally halogen- or cyano-substituted C1-C30-hydrocarbon radical in which one or more, non-neighboring methylene units may be replaced by groups â€”Oâ€”, â€”COâ€”, â€”COOâ€”, â€”OCOâ€” or â€”OCOOâ€”, â€”Sâ€” or â€”NRxâ€” and in which one or more, non-neighboring methine units may be replaced by groups â€”N&boxH;, â€”N&boxH;Nâ€” or â€”P&boxH;, R2 denotes hydrogen or an optionally halogen- or cyano-substituted C1-C30-hydrocarbon radical in which one or more, non-neighboring methylene units may be replaced by groups â€”Oâ€”, â€”COâ€”, â€”COOâ€”, â€”OCOâ€” or â€”OCOOâ€”, â€”Sâ€” or â€”NRxâ€” and in which one or more, non-neighboring methine units may be replaced by groups â€”N&boxH;, â€”N&boxH;Nâ€” or â€”P&boxH;, R3 and R4 denote hydrogen, halogen or an optionally halogen- or cyano-substituted C1-C30-hydrocarbon radical in which one or more, non-neighboring methylene units may be replaced by groups â€”Oâ€”, â€”COâ€”, â€”COOâ€”, â€”OCOâ€” or â€”OCOOâ€”, â€”Sâ€” or â€”NRxâ€” and in which one or more, non-neighboring methine units may be replaced by groups â€”N&boxH;, â€”N&boxH;Nâ€” or â€”P&boxH;, Rx denotes hydrogen or an optionally halogen- or cyano-substituted C1-C30-hydrocarbon radical in which one or more, non-neighboring methylene units may be replaced by groups â€”Oâ€”, â€”COâ€”, â€”COOâ€”, â€”OCOâ€” or â€”OCOOâ€”, â€”Sâ€”, â€”NHâ€” or â€”Nâ€”C1-C20-alkyl and in which one or more, non-neighboring methine units may be replaced by groups â€”N&boxH;, â€”N&boxH;Nâ€” or â€”P&boxH;, and M denotes hydrogen, an alkali metal ion, an alkaline earth metal ion or an ammonium ion, where in each case 2 radicals which are selected from the pairs R1 and R2, R3 and R4 and R1 and R3 can be linked to one another.