cas 384-67-8, 2-CHLORO-2,2-DIFLUOROACETOPHENONE

Articles about 384-67-8Total 11 be found

Unusual reactions of Grignard reagents toward fluoroalkylated esters
Fluorine-containing esters were demonstrated to be convenient substrates for construction of the corresponding ketones by low temperature reaction with Grignard reagents followed by warming up to 0 °C, while heating the mixture up to 80 °C readily promoted the reduction of the ketones obtained by the generated magnesium alkoxides whose mechanism was speculated as Meerwein-Ponndorf-Verley type reduction by computational technique.
Yamazaki, Takashi,Terajima, Tsukasa,Kawasaki-Taskasuka, Tomoko
p. 2419 - 2424
(2008/09/18)

Synthesis of 3-substituted 2-fluoro- And 2,2-difluoroaziridines
A new route for the synthesis of stable 3-alkyl- and 3-aryl-2(,2)-(di) fluoroaziridines was developed by hydride reduction of novel α-bromo- and α-chloro-α(,α)-(di)fluoroketimines and subsequent ring closure of β-fluorinated β-chloro- and β-bromoamines. T
Van Hende, Eva,Verniest, Guido,Surmont, Riccardo,De Kimpe, Norbert
p. 2935 - 2937
(2008/02/07)

2-Chloro-2,2-difluoroacetophenone: A non-ODS-based difluorocarbene precursor and its use in the difluoromethylation of phenol derivatives
A novel and non-ODS-based (ODS = ozone-depleting substance) preparation of 2-chloro-2,2-difluoroacetophenone (1) was achieved in high yield by using 2,2,2-trifluoroacetophenone as the starting material. Compound 1 was found to act as a good difluorocarbene reagent, which readily reacts with a variety of structurally diverse phenol derivatives 4 in the presence of potassium hydroxide or potassium carbonate to produce aryl difluoromethyl ethers 5 in good yields. This new and easy-to-handle synthetic methodology offers an environmentally friendly alternative to other Freon- or Halon-based difluoromethylating approaches.
Zhang, Laijun,Zheng, Ji,Hu, Jinbo
p. 9845 - 9848
(2007/10/03)

Evidence for a stepwise addition of carbenes to strained double bonds: Reactions of dihalocarbenes with cyclopropenes
Zwitterionic species are most likely the intermediates for the formation of 1,1-dihalo-2,3-diarylbutadienes by addition of dihalocarbenes to 1,2-diarylcyclopropenes [Eq. (a)]. Bicyclobutanes can be ruled out as intermediates for the formation of butadiene
Weber,Brinker
p. 1623 - 1626
(2007/10/03)

Lewis Acid Catalyzed Aldol-Type Reaction of 1,1-Difluorovinyl Methyl Ether Derivatives
In the presence of Lewis acid, such as SbCl5, SbCl6*NAr3 or Cu(OTf)2, difluorovinyl methyl ether (1,1-difluoro-2-methoxy-1-alkene) 1 reacted with carbonyl compounds to give O-methylated aldol-type products 3 in good yields, while Lewis acid, such as TMSOT
Kodama, Yoshitoshi,Yamane, Hidefumi,Okumura, Masato,Shiro, Motoo,Taguchi, Takeo
p. 12217 - 12228
(2007/10/02)

A microbially-based approach for the synthesis of chiral secondary alcohols bearing the difluoromethyl or chlorodifluoromethyl group
A synthetic approach to both enantiomers of the secondary alcohols , involving the stereoselective hydrolysis of ester derivatives, is described.The absolute configurations of these difluoromethylated or chlorodifluoromethylated molecules were determined.
Kitazume, Tomoya,Asai, Masatomo,Tsukamoto, Takashi,Yamazaki, Takashi
p. 271 - 284
(2007/10/02)

ARYLPOLYFLUOROLEFIN PEROXIDES. I. SYNTHESIS OF α,β,β-TRIFLUOROSTYRENE, β-CHLORO-α,β-DIFLUOROSTYRENE, AND (PERFLUOROPROPENYL)BENZENE EPOXIDES
By the oxidation of α,β,β-trifluorostyrene, β-chloro-α,β-difluorostyrene, and (perfluoropropenyl)benzene with oxygen in presence of chlorine and UV radiation 1,2-epoxy-1,2,2-trifluoro-1-phenylethane, 2-chloro-1,2-epoxy-1,2-difluoro-1-phenylethane, and 1,2-epoxy-1,2,3,3,3-pentafluoro-1-phenylpropane were prepared. α,β,β-Trifluorostyrene and β-chloro-α,β-difluorostyrene epoxides under the action of triethylamine are rearranged into difluorophenylacetyl and chlorofluorophenylacetyl fluorides, by the hydrolysis of which the corresponding acids are obtained. β-Chloro-α,β-difluorostyrene epoxide reacts with fluoride ions with the formation of a mixture of chlorofluorophenylacetic acid and 2,2,2-trifluoro- and 2-chloro-2,2-difluoro-acetophenones.
Kremlev, M. M.,Maznyi, I. S.,Yagupol'skii, L. M.
p. 105 - 108
(2007/10/02)

An efficient and general method for the reformatsky-type reaction of chlorodifluoromethyl ketones with carbonyl compounds giving α,α-difluoro-β-hydroxy ketones1)
Chlorodifluoromethyl ketones CF2ClCOR, where R is an alkyl, aryl, and l-alkynyl group, underwent the Reformatsky-type aldol reaction with a wide variety of aldehydes or ketones in the presence of acid-washed zinc dust and copper(I) chloride or
Kuroboshi,Ishihara
p. 428 - 437
(2007/10/02)

SYNTHESIS OF A NOVEL CARBAPENEM-POTASSIUM (5R,6R)-1,1-DIFLUORO-2-PHENYL-6-(1R-HYDROXYETHYL)-CARBAPEN-2-EM-3-CARBOXYLATE. THE USE OF A NEW N-PROTECTING GROUP IN &β-LACTAM SYNTHESIS
A synthesis of a novel 1,1-difluorocarbapenem (1), utilizing a new N-protecting group for the position of 2-azetidinones is described.
Shah, Nalini V.,Cama, Lovji D.
p. 221 - 227
(2007/10/02)

Proton-Transfer Reactions. 2. Effects of Internal Return on Reactivity Difference between Alkoxide-Promoted Eliminations in tert-Butyl alcohol and Ethyl Alcohol
Kinetics of alkoxide-promoted dehydrofluorination reactions are reported for the series C6H5CH2CH2F (I), C6H5CH2CHF2 (II), C6H5CH2CF3 (III), and C6H5CH2CF2CF3 (V).Rates and activation parameters 3 (M-1 s-1)(50 deg C), ΔH* (kcal mol-1), and ΔS*, (eu)> are respectively: (a) using potassium tert-butoxide in tert-butyl alcohol, I (1.88 * 10-4, 19.1, -16.8), II (1.18 * 10-3, 20.3, -9.3), III (2.15 * 10-3, 22.1, -2.4), V (3.93 * 10-2, 16.9, -12.7); and (b) using sodium ethoxide in ethanol, I (1.32 * 10-6, 25.6, -6.5), II (5.28 * 10-7, 29.7, 3.0), III (3.45 * 10-7, 32.6, 12.5), V (5.41 * 10-5, 27.7, 7.6).The variation in tert-butoxide:ethoxide ratios of 140 (I), 2200 (II), 6200 (III), and 730 (V) are discussed in terms of a two-step mechanism with varying amounts of internal return for II, III, and V.Differences in reactivity for groups attached to the benzylic carbon (-CF3, -CF2Cl, -CHF2, -CF2CF3) and variation of ΔS* values for these reactions are also discussed in terms of a two-step mechanism.
Koch, H. F.,Tumas, W.,Knoll, R.
p. 5423 - 5429
(2007/10/02)