816-38-6Relevant academic research and scientific papers
REACTION OF ORGANIC COMPOUNDS WITH SF4-HF-HALOGENATING SYSTEM VII. REACTIONS OF OLEFINS WITH THE SF4-HF-Cl2(Br2) SYSTEM
Kunshenko, B. V.,Mokhamed, Nagib Mukhtar,Omarov, V. O.,Muratov, N. N.,Yagupol'skii, L. M.
, p. 511 - 518 (2007/10/02)
Under the influence of the SF4-HF-Cl2(Br2) system halogen-containing olefins undergo conjugate halogenofluorination.It was shown for the case of (Z)- and (E)- 1,2-dichloroethenes that these reactions take place anti-stereospecifically through the formation of the bromonium ions.The accumulation of chlorine atoms in the olefin molecule hinders electrophilic addition of stoichiometric equivalents of ClF and BrF at the double bond.The SF4-HF-Br2 system is an effective agent for substitutive fluorination of organic compounds containing bromine.Only the bromine atoms situated at the secondary carbon atom are substituted by fluorine.
REACTIONS OF CHLORINE MONOFLUORIDE. SUBSTITUTION OF CHLORINE ATOMS BY FLUORINE IN CHLORINE-SUBSTITUTED ALKANES AND ESTERS
Chuvatkin, N. N.,Panteleeva, I. Yu.,Boguslavskaya, L. S.
, p. 821 - 827 (2007/10/02)
In anhydrous hydrogen fluoride under mild conditions chlorine monofluoride selectively substitutes the chlorine atoms in chlorine-substituted alkanes and esters by fluorine with the formation of high yields of the corresponding fluorides.The presence of an alkoxycarbonyl group or difluoromethylene group at the α position to the CHCl group deactivates the chlorine atom, and substitution by fluorine does not occur.In chloroalkanes, from which elimination of the chloride ion leads to sufficiently stable carbocations, substitution by fluorine can be realized in the absence of hydrogen fluoride at temperatures between -20 and -60 deg C.The fluorinating capacity of chlorine monofluoride is increased in the presence of catalytic amounts (3-5percent) of antimony pentachloride.Here the reaction is less selective than in hydrogen fluoride.In certain cases substitution is accompanied by hydride transfers.
