7656-99-7Relevant articles and documents
A New Trifluoromethylating Agent: Synthesis of Polychlorinated (Trifluoromethyl)benzenes and 1,3-Bis(trifluoromethyl)benzenes and Conversion into Their Trichloromethyl Counterparts and Molecular Structure of Highly Strained Polychloro-m-xylenes
Castaner, J.,Riera, J.,Carilla, J.,Robert, A.,Molins, E.,Miravitlles, C.
, p. 103 - 110 (2007/10/02)
Mixtures of CCl3F and AlCl3 replace CF3 for H in polychlorobenzenes.Thus, by treatment of a solution of the suitable polychlorobenzene in CCl3F with AlCl3, the following compounds can be prepared: pentachloro- (2), 2,3,4,5-tetrachloro- (5), 2,3,4,6-tetrachloro- (8), 2,3,5,6-tetrachloro- (11), 2,3,4-trichloro- (14), 2,4,5-trichloro- (17), and 2,4,6-trichloro-1-(trifluoromethyl)benzene (20), as well as 4,5,6-trichloro- (31) and 2,4,6-trichloro-1,3-bis(trifluoromethyl)benzene (32).The reaction of the above-mentioned trifluoromethylated compounds with AlCl3 in CS2 yieldstheir trichloromethyl counterparts: 3, 6, 9, 12, 15, 18, 21, 34, and 36.The chlorination of 32 or 36 by means of Silberrad's reagent (SO2Cl2, AlCl3, and S2Cl2) affords perchloro-m-xylene (38), a new highly strained chlorocarbon whose synthesis was attempted repeatedly in the past. 9, 15, 17, and 21, when treated with oleum and then with water, are converted into 2,3,4,6-tetrachloro- (22), 2,3,4-trichloro- (23), 2,4,5-trichloro- (24), and 2,4,6-trichlorobenzoic acid (25), respectively; under similar treatment, 34, 36, and 38 give 4,5,6-trichloro- (33), 2,4,5-trichloro- (35), and tetrachloroisophthalic acid (39), respectively.The formation of the (trifluoromethyl)benzenes is discussed, and in this connection it has been found that CCl3F solutions of 3 and 18 in the presence of AlCl3 give back 2 and 17, respectively.Molecular structures of highly strained m-xylenes 36 and 38, as well as that of the much less strained 34, ascertained by X-ray analysis, are reported and commented.IR, UV, and NMR spectral data of the compounds synthesized are presented.The interesting UV spectrum of 21 is discussed.
RELATIONSHIPS AND KINETICS OF THE EXHAUSTIVE CHLORINATION OF m-CHLOROTRIFLUOROMETHYLBENZENE AND TRIFLUOROMETHYLBENZENE
Alikhanov, P. P.,Ushakov, A. A.,Kuznetsova, G. N.,Kalinachenko, V. R.,Motsarev, G. V.
, p. 734 - 740 (2007/10/02)
The exhaustive electrophilic chlorination of m-chlorotrifluoromethylbenzene and trifluoromethylbenzene, catalyzed by ferric chloride , was investigated on the basis of a correlation approach.The relationships governing the regulation of the reactivity of the chlorine derivatives of trifluoromethylbenzene were studied.A quantitative relation was established between the direction of chlorination and the effects of the substituents; the effects of the latter remain unchanged in the polychloro derivatives of trifluoromethylbenzene, while the overall effect is close to additive.The distribution of the isomers was determined for various degrees of substitution of trifluoromethylbenzene: monochloro, 2- , 3- , 4- ; dichloro, 2,5- , 3,4- , 2,3- , 3,5- ; trichloro, 2,3,5- and 2,4,5- , 3,4,5- , 2,3,6- , 2,3,4- ; tetrachloro-, 2,3,5,6- , 2,3,4,5- .The following derivatives are formed during the chlorination of m-chlorotrifluoromethylbenzene: dichloro, 2,5- , 3,4- , 2,3- , 3,5- ; trichloro, 2,3,5- and 2,4,5- , 3,4,5- , 2,3,6- , 2,3,4- ; tetrachloro, 2,3,5,6- , 2,3,4,5- .The distribution of the isomers agrees with the distribution calculated on the basis of the employed parameters and the additivity principle.The compositions of the products with various degrees of chlorination are given satisfactorily by kinetic curves describing a multistage system of consecutive and parallel irreversible first-order reactions.
