As a prior art relating to the present invention, for example, in German (DE) Patent No. 11 62 359, Angewandte Chemie International Edition in English (Angew. Chem. Int. Ed. Eng.), 2688 (1963), Chim. Ind. (Milan), 46, 875 (1964), German (DE) Patent No. 12 05 089, Bulletin de la Societe Chimique de France (Bull. Soc. Chim. Fr.), 10, 2833 (1965), Italian (IT) Patent No. 720514, Journal für Practische Chemie (J. Pract. Chem.), 33, 282 (1966), Japanese Patent Publications No. Sho. 43-16124 and Sho. 44-3815, there are description about hydrogen reduction of 2-halogenocycloalkenone oxime compounds including 2-chlorocyclododecadienone oxime using a palladium catalyst. However, main products in these reactions are cycloalkanone oxime in which not only carbon-carbon double bond(s) but also a chloro group are also reduced.
Also, in Bull. Soc. Chim. Fr., 10, 2833 (1965), an example of obtaining 2-chlorocyclododecanone oxime from 2-chlorocyclododecadienone oxime using platinum oxide has been described but the yield is extremely low as 10%, so that it is not satisfied. Also, since a platinum oxide catalyst is dissolved during the reaction, so that there is a problem that it's recovery and reuse are not so easy.
Thus, the halogen group of the 2-halogenocycloalkenone oxime compound is extremely easily reduced, so that it has not been known a method of selectively reducing carbon-carbon double bond(s) of the 2-halogenocycloalkenone oxime compound in good yield.
An object of the present invention is to solve the above-mentioned problems and to provide a process for preparing a 2-halogenocycloalkanone oxime in high yield by selectively reducing carbon-carbon double bond(s) of a 2-halogenocycloalkenone oxime compound with good efficiency.