Patent GB-415715-A (GB)
Title: The manufacture of therapeutic media
IPC: C07C37/14
Filed: 1933-02-28
Abstract: Polyhydroxyhalogenbenzenes, substituted in the nucleus with an alkyl group of 6--12 carbon atoms, are prepared by any of the following processes:--(1) halogenation of a polyhydroxybenzene substituted by an alkyl group of 6--12 carbon atoms (illustrated by examples 1--5 below); halogenation may be effected with p  elementary halogen in the presence of a known catalyst, such as iron or aluminium chloride; iodine chloride or a sulphuryl halide may also be used as halogenating agents; halogenation with a sulphuryl halide is preferably effected at a raised temperature in the presence of a solvent, a number of which are specified; (2) condensation of a polyhydroxy-halogenbenzene with an aliphatic alcohol containing 6--12 carbon atoms (illustrated by example 9 below); the reaction is preferably effected in the presence of a condensing agent such as zinc chloride or sulphuric acid; the alcohol may be replaced by an unsaturated aliphatic hydrocarbon containing 6--12 carbon atoms (cf. example 10 below); (3) conversion of a polyhydroxy-halogenbenzene into an acylpolyhydroxy-halogenbenzene containing an aliphatic carboxylic acid radicle of 6--12 carbon atoms, followed by reduction of the acid radicle (cf. examples 6 and 8 below); (4) treatment of an additionally substituted alkylhalogenbenzene or alkylhalogenphenol (the alkyl group containing 6--12 carbon atoms) so as to replace the additional substituent or substituents by a hydroxy group or groups (cf. example 6 below).  The products are useful as therapeutic antiparasitic agents.  In the examples, (1) 1-n-octyl-5-chloro-2 : 4-resorcinol is prepared by treating 1-n-octyl-2 : 4-resorcinol with sulphuryl chloride; (2) a dichloro1-n-hexyl-2 : 4-resorcinol, and its 1-n-heptyl-and 1-n-octyl-homologs, are prepared by treating the corresponding unchlorinated resorcinols with sulphuryl chloride; (3) a dichloro-1-n-octyl-2 : 4-resorcinol is prepared by treating 1-n-octyl-2 : 4-resorcinol in acetic acid solution with chlorine in the presence of powdered iron; (4) a dibromo-1-n-decyl-2 : 4-resorcinol is prepared by treating 1-n-decyl-2 : 4-resorcinol in carbon tetrachloride with bromine; (5) 1-n-octyl-5-chloro-2 : 4-resorcinol is prepared by treating 1-n-octyl-2 : 4-resorcinol in nitrobenzene solution with sulphuryl chloride; a chlorododecylresorcinol is similarly obtainable; (6) 5-octyl-4-chloro-1 : 2-pyrocatechol is prepared by heating 4-chloro-1 : 2-pyrocatechol with octylic acid in the presence of zinc chloride, and reducing with amalgamated zinc and hydrochloric acid the 5-octylyl-4-chloro-1 : 2-pyrocatechol so obtained; an octyl-4-chloro-1 : 2 : 3-pyrogallol and an octyl-2-bromo-1 : 4-hydroquinone are similarly obtainable; (7) 6-isooctyl-4-chloro-1 : 2-pyrocatechol is prepared by heating 6-isooctyl-4-chloro-2-bromophenol with aqueous caustic soda; (8) a butylhexyl-chlororesorcinol is prepared by condensing a chlororesorcinol with dibutylacetic acid, and reducing with amalgamated zinc and hydrochloric acid the dibutylacetylchloro-resorcinol so obtained; (9) an isohexylchlororesorcinol is prepared by heating a chlororesorcinol with n-heptyl alcohol in the presence of zinc chloride; (10) a heptylchlororesorcinol is prepared by heating a chlororesorcinol with methyldiethylethylene in the presence of zinc chloride. 6-Isooctyl-4-chloro-2-bromophenol, used in example 7, is prepared by heating 4-chlorophenol with n-octyl alcohol in the presence of zinc chloride, and brominating the 6-isooctyl-4-chlorophenol so obtained. Dibutylacetic acid, used in example 8, is prepared by the standard malonic acid synthesis.  The Specification, as open to inspection under Sect. 91, indicates that the alkylpolyhydroxyhalogenbenzenes may be prepared from alkylhalogenaminophenols by converting the amino group into a hydroxy group by way of the diazo compound.  This subject-matter does not appear in the Specification as accepted.