Patent GB-748224-A (GB)
Title: Improvements in or relating to bis-quaternary ammonium salts
Inventor: SLACK RONALD
IPC: C07D295/02
Filed: 1953-02-17
Abstract: The invention comprises compounds of the general formula <FORM:0748224/IV(a)/1> wherein R1 and R4 represent identical or different alkyl groups of up to 4 carbon atoms, R2, R3, R5 and R6 are identical or different and either represent individual alkyl groups of up to 4 carbon atoms or the pairs R2, R3 and R5, R6 respectively form with the adjacent nitrogen atom a saturated heterocyclic group, Y represents a trimethylene, phenylene or cyclohexylene group, Z represents an alkylene chain containing 1-8 carbon atoms, and A represents the residue of 4:41-diaminostilbene-2:21-disulphonic acid (referred to as "amsonic acid" and its salts as "amsonates"); the preparation thereof by treating an aqueous solution containing another salt of the same quaternary ammonium base with a water-soluble salt of amsonic acid; and a process for isolating a water-soluble quaternary ammonium salt having a cation of the formula <FORM:0748224/IV(a)/2> from an acid-free aqueous solution containing soluble by-products, by adding a water-soluble salt of amsonic acid, removing and purifying the salt (of the first formula above) thus precipitated, dissolving the purified salt in hot water, treating the solution with the acid corresponding to the desired product, removing the precipitated amsonic acid, and isolating the desired salt from the impurity-free solution.  In examples: (1) an aqueous solution of hexamethylene - 1:6 - bis - (trimethylammonium bromide) is added to a warm aqueous solution of disodium amsonate, and the quaternary ammonium amsonate which crystallizes on cooling is filtered off, dissolved in warm water and treated with d-tartaric acid to produce the quaternary ammonium bitartrate; phenyl-n-propane-p:o -bis-(trimethylammonium iodide) similarly yields the corresponding amsonate; (2) amsonic acid is dissolved in dilute aqueous caustic soda and an aqueous solution of hexamethylene-1:6-bis-11-(11-methylpyrrolidinium di-iodide) is added; (3) a warm aqueous solution of the a -form of cyclohexylethane-4:o -bis-(trimethylammonium iodide) is added to a warm solution of amsonic acid in aqueous ammonia, and the resulting quaternary ammonium amsonate is converted to the dichloride; (4) phenylethane-p:o -bis-(trimethylammonium iodide) is similarly converted into the amsonate, and the latter into the dichloride, sulphate or bitartrate; (5) 5-p-di-methylaminophenyl - n - amyldimethylamine is refluxed with ethyl iodide in ethanol and the resulting quaternary ammonium iodide is converted as in (3) into the amsonate, and the latter into the bitartrate; phenyl-n-pentane-p:o -bis-(methyldiethylammonium iodide) may be similarly treated; (6) a warm aqueous solution of crude pentamethylene - 1:5 - bis - 11 - (11 - methylpyrrolidinium bromide) is added to a warm solution of amsonic acid in aqueous ammonia; (7) diethylmethylamine is heated with 1:4-dibromobutane in methanol, and a warm solution of amsonic acid in aqueous ammonia is added to a warm aqueous solution of the product to produce tetramethylene-1:4-bis-(diethylmethylammonium amsonate), which is converted to the bitartrate.  Specifications 705,506, 705,528, 714,867, 723,205, 723,210, 723,232, 748,214 and 748,217 are referred to.