35621-92-2Relevant academic research and scientific papers
Methoxide-induced fragmentation of 2,2,3-trihalogeno- and 2,2-dihalogeno-3-methoxy-1,3-diphenylpropanones
Montani, Rosana S.,Garay, Raul O.,Cabaleiro, Mercedes C.
, p. 1125 - 1130 (2007/10/02)
The reaction of 2,2,3-trihalogeno-1,3-diphenylpropanones with sodium methoxide in methanol occurs with exclusive formation of fragmentation products.Kinetic and stereochemical evidence is interpreted in terms of a concerted intramolecular process promoted by initial attack of methoxide anion at the carbonyl carbon.In the case of 2,2-dihalogeno-3-methoxy-1,3-diphenylpropanones the reaction gives fragmentation, rearrangement, and elimination products.The former products are believed to be formed through competing reactions involving an intermediate formed on addition of methoxide to the substrate.For the fragmentation pathway the results are consistent with a carbanionic-intermediate mechanism.
Nucleophilic attack on halogeno(phenyl)acetylenes by halide ions
Tanaka, Ryuichi,Zheng, Shi-Qin,Kawaguchi, Kenji,Tanaka, Takehide
, p. 1714 - 1720 (2007/10/02)
Nucleophilic reactions between halogeno(phenyl)acetylenes and halide ions, ArC≡CX + Y-, where Ar = C6H5 or p-ClC 6H4, X = Cl or Br, and Y = Cl or Br, have been examined. Halogen exchange of the Finkelstein type was observed for the first time in acetylene halides in anhydrous dimethyl sulphoxide when X = Br and Y = Cl. This exchange did not occur with other X-Y combinations. In the presence of up to 20% water in dimethyl sulphoxide, or under aqueous-organic phase-transfer catalytic conditions, nucleophilic addition (formally of HY) took place for all the X-Y combinations studied. In the additions, the nucleophile Y- invariably attacked the carbon to which the phenyl group was bound. The mode of HY addition was stereospecifically trans; accordingly, the resulting dihalogenostyrenes always had the (Z)-1,2-dihalogeno-configuration.
