34509-09-6Relevant articles and documents
Trifluoromethyl ketones from enolizable carboxylic acids via enediolate trifluoroacetylation/decarboxylation
Reeves, Jonathan T.,Song, Jinhua J.,Tan, Zhulin,Lee, Heewon,Yee, Nathan K.,Senanayake, Chris H.
supporting information; experimental part, p. 9476 - 9478 (2009/04/06)
(Chemical Equation Presented) Primary and secondary (enolizable) carboxylic acids were converted in a single step to trifluoromethyl ketones. Treatment of the acid with 2.2 equiv of LDA generated an enediolate that was trifluoroacetylated with EtO2CCF3. Quenching the reaction mixture with aqueous HCl resulted in rapid decarboxylation and provided the trifluoromethyl ketone product in good yield. The process may be performed at -20°C with a slight reduction in yield. The reaction was extended to the preparation of pentafluoroethyl and chlorodifluoromethyl ketones.
α- or β-Trifluoromethyl epoxysulfones: new C3 reagents for heterocyclisation
Laduron, Frederic,Janousek, Zdenek,Viehe, Heinz, G.
, p. 83 - 86 (2007/10/02)
The syntheses of α- and β-trifluoromethyl epoxysulfones 1 and 2 are described.Compound 1 reacts with nucleophiles and bis-nucleophiles to furnish trifluoromethyl ketones and trifluoromethyl heterocycles in good yield, while its isomer 2 leads to the opposite thiazole regioisomers with thioamides. - Keywords: Trifluoromethyl epoxysulfones; Heterocyclisation; Regioisomers; NMR spectroscopy; IR spectroscopy
2-HALOVINYL ARYL SULFONES: NEW COUPLING REAGENTS FOR CARBOXAMIDE FORMATION
Shimagaki, Masayuki,Koshiji, Hiroko,Oishi, Takeshi
, p. 45 - 58 (2007/10/02)
E-2-Chlorovinyl p-nitrophenyl sulfone 6 and 2-bromo-2-trifluoromethylvinyl phenyl sulfone 7a reacted with carboxylic acids in the presence of a molar equiv of Et3N affording the corresponding 2-acyloxyvinyl sulfones 8, 11, 17, 18, 22, 25, 28 and 29.The latter, on treatment with amines, gave amides 9, 13, 19, 23 and 26 and peptides 30 and 32.These reagents 6 and 7a were also used for the formation of N-methylanilides 13d, 13e, 19d, 23 and 26.Particularly, 6 was successfully used for synthesis of a macrocyclic lactam 23 involving a N-methylanilide moiety.The amidation reac tions proceeded under essentially neutral conditions.Therefore, base-sensitive β-hydroxycarboxy-N-methylanilides such as 26, whose structural unit was involved in maytansine 5, could be prepared by the present method.The reagent 6 was also effective for the preparation of peptides such as Val-N-MeVal derivatives (e.g.32), which were difficult to prepare by other methods.
