2136-87-0Relevant academic research and scientific papers
Process for the production of 4-amino-3,5-dichlorobenzotrifluoride with high purity commercial products being obtained in parallel
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Page/Page column 5-8, (2008/06/13)
Process for the production of 4-amino-3,5-dichlorobenzotrifluoride comprising the stages:A) chlorination of 4-chlorobenzotrichloride, in the presence of a Lewis acid, in order to obtain a mixture of 3,4-dichlorobenzotrichloride and 3,4,5-trichlorobenzotrichloride and other chlorine derivatives by performing the reaction in such a manner as to obtain in the mixture of reaction products a quantity of 3,4,5-trichlorobenzotrichloride of greater than 10% by weight and preferably of between 20% and 30% by weight and a concentration of 3,4-trichlorobenzotrichloride of less than 90% by weight and preferably of between approx. 55% and 75% by weight, relative to the total weight of the chlorinated derivatives;B) fluorination with hydrofluoric acid of the mixture of chlorination products as obtained in stage A) in order to obtain the corresponding benzotrifluorides; andC) separation by distillation of the mixture of products of stage B) in order to obtain 3,4,5-trichlorobenzotrifluoride or an isomeric mixture of 3,4,5- and 2,4,5-trichlorobenzotrifluoride; andD) amination of 3,4,5-trichlorobenzotrifluoride or of said isomeric mixture.
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.
NEW SYNTHESIS OF POLYCHLORO(TRIFLUOROMETHYL)BENZENES AND HIGHLY STRAINED POLYCHLORO(TRICHLOROMETHYL)BENZENES
Riera, Juan,Castaner, Juan,Carilla, Jose,Robert, Ana
, p. 3825 - 3828 (2007/10/02)
Several polychloro(trifluoromethyl)benzenes have been prepared by treatment of the corresponding polychlorobenzenes with CCl3F and AlCl3.The resulting trifluoromethyl derivatives, by reaction with the same inorganic halide in CS2, give their trichloromethyl analogues.
