38756-53-5Relevant academic research and scientific papers
Reactions of alicyclic ketones in carbon tetrachloride. II. Kinetics of the chlorination of 2-chlorocyclopentanone and 2-chlorocyclohexanone, catalyzed by hydrogen chloride
Stamhuis, Eize J.,Maatman, Henk,Joosten, Geert E. H.
, p. 1690 - 1696 (2007/10/02)
The kinetics of the direct chlorination of 2-chlorocyclopentanone (2-mccp) and 2-chlorocyclohexanone (2-mcch) in carbon tetrachloride, catalyzed by hydrogen chloride, were studied.Reaction products are all the possible 2,2-, 2,5-, and 2,6-dichloro compounds.The ratios depend on the concentrations of the monochloro compound and hydrogen chloride.Surprisingly, even at conversions of the monochloro compound as low as 2percent, 2,2,5-trichlorocyclopentanone and 2,2,6-trichlorocyclohexanone, respectively, are also formed.The chlorination of both monochloro ketones shows zero order in chlorine.The order in hydrogen chloride is 1.3.The order in 2-mccp and 2-mcch varies somewhat with the concentration of the ketone and was found to be roughly 1.7.The variation in reaction order is explained by a partial self-association of the ketones.The ketones act as substrates as well as basic catalysts in the rate-determining α- or α'-carbon deprotonation.General base catalysis is clearly demonstrated by a strong increase in the rate of chlorination of 2-mccp upon addition of cyclopentanone (cp) to the reaction mixture, which agrees with the mechanism as presented in a previous paper.Kinetic equations derived from the reaction models for the "separate" and "mixed" ketone chlorinations accurately describe the observed rates of the chlorination of 2-mccp and 2-mcch in the concentration range of 0.04 - 1.0 M.
PRACTICAL SYNTHESIS OF 2,2,5,5-TETRACHLORO-1,6-HEXANEDIOIC ACID, FROM TRANS-1,2-CYCLOHEXANEDIOL OR CYCLOHEXANONE, INVOLVING OXIDATION OF 3,3,6,6-TETRACHLORO-1,2-CYCLOHEXANEDIONE
Buyck, Laurent de,Vanslembrouck, Jan,Kimpe, Norbert de,Verhe, Roland,Schamp, Niceas
, p. 913 - 918 (2007/10/02)
Trans-1,2-cyclohexanediol was quantitatively converted into 3,3,6,6-tetrachloro-1,2-cyclohexanedione (2) by treatment with chlorine in dimethylformamide.The hydrate of the dione was oxidized by aqueous potassium permanganate to afford the title acid 1 in 91percent overall yield.An alternative low cost preparation was elaborated, providing 2 in 61-74percent yield starting from cyclohexanone in a three step procedure without isolation of intermediates.The reaction seqence involves substitution of α-dichloro- and trichlorocyclohexanones by sodium acetate in acetic acid and chlorination of the resulting 2-hydroxy- and 2-acetoxy-2-cyclohexenones in dimethylformamide.
