Patent GB-826619-A (GB)
Title: A process for the production of fluorine, bromine and iodine substituted organic compounds
IPC: C07F3/02
Filed: 1956-05-04
Abstract: Fluorine, bromine or iodine substituted organic compounds of the formula RF(Br or I), wherein R is hereinafter defined, are prepared by reacting fluorine, bromine or iodine with an organomagnesium chloride complex of the general formula R(MgCl)x.nQ, wherein R represents a substituted or unsubstituted aryl radical, a substituted or unsubstituted vinyl radical, or a substituted or unsubstituted heterocyclic radical which exhibits aromatic or pseudo-aromatic characteristics, which includes in its heterocyclic ring an oxygen, sulphur or tertiary nitrogen atom and which is bound to magnesium through a carbon atom of the aromatic or pseudo-aromatic ring and R contains no functional group which is reactive under the conditions for the formulation of the complex, n is 1, 2 or 3, x is an integer, and Q represents a substituted or unsubstituted cyclic ether having 5 or 6 carbon atoms in the ring, of which atoms only one is oxygen, the other ring atoms being carbon with the exception that a substituted nitrogen atom may replace the carbon atom in the 4-position when the ring has 6 atoms, the ring containing not more than one double bond and at least one carbon atom in the ring adjacent to the oxygen atom being free of any substituents, said cyclic ether containing no substituent which is reactive with organomagnesium chlorides or with any of the other components or the products of the process.  The compound Q, which may be tetrahydrofuran, tetrahydropyran, 2-methyltetrahydrofuran, 2-ethoxytetrahydropyran, tetrahydrofurfuryl ethyl ether, dihydropyran or N-methylmorpholine, may be used as the reaction solvent or an inert hydrocarbon reaction solvent may be used. Reaction temperatures may vary from room temperature up to reflux temperatures.  Substituents which may be present in the compound Q are inert substituted and unsubstituted alkyl, aryl, alkoxy and aryloxy radicals.  The radical R may be an aryl radical of the general formula <FORM:0826619/IV (b)/1> wherein Ra, Rb, Rc, Rd and Re are the same or different and represent hydrogen, fluorine or chlorine, such as the various chloro-substituted phenyl and xenyl radicals, an alkyl radical such as a methyl or ethyl radical; an alkenyl radical such as a vinyl, allyl or propenyl radical; an aryl radical such as a phenyl, tolyl, xylyl or xenyl radical, an aralkyl radical such as a benzyl, phenylethyl, cinnamyl or methylbenzyl radical; a heterocyclic radical such as a thienyl, thenyl or furyl radical; an alkoxy radical such as a methoxy or ethoxy radical; an alkenyloxy radical such as an allyloxy radical; an aryloxy radical such as a phenoxy, tolyoxy or xenyloxy radical; and a dialkylamino radical such as a dimethylamino or diethylamino radical.  The radical R may also be derived from diphenyl, naphthalene, anthracene, terphenyl or phenanthrene.  A large number of suitable heterocyclic radicals which R may represent are also referred to which may be substituted by fluorine or chlorine or alkyl, alkenyl, aryl, alkoxy, aryloxy or other nonreactive groups.  As regards the vinyl radicals which R may represent, in the case where x represents 1, the R radical may be of the formula <FORM:0826619/IV (b)/2> wherein R1, R11 and R111 may be the same o different and represent hydrogen or a substituted or unsubstituted aliphatic or aromatic hydrocarbon radical, wherein R1 may be cyclized with R11 or R111 and wherein R111 may represent chlorine, and in the case where x represents 2, the R radical may be a bivalent radical of the formula <FORM:0826619/IV (b)/3> wherein R1 and R11 have the significance previously indicated. In the examples iodobenzene, p-fluoro-toluene, p-bromochlorobenzene, 2,4 - dimethyliodobenzene, p - bromo - anisole, p-iodo-N,N-dimethylaniline, vinyl fluoride, benzyl iodide, 2-bromo-thiophene, pentachloro - iodobenzene, a  - iodonaphthalene, 2 - methyl-4-iodopyridine, cyclohexenyl bromide and pentamethyleneiodo chloride are prepared.  Specifications 776,993, 777,158, 779,100 and 826,620 are referred to.