Patent GB-805931-A (GB)
Title: New organic compounds containing phosphorus and sulphur and processes for their manufacture
IPC: C07F9/17
Filed: 1955-03-03
Abstract: The invention comprises asymmetrical ester salts of thiophosphoric acid of the general formula <FORM:0805931/IV (b)/1> in which R1 is the residue of an alcohol, R2 is the residue of an alcohol different from R1 and M is a salt-forming cation.  They may be obtained by additively combining sulphur with a compound of the general formula <FORM:0805931/IV (b)/2> in which R1 and R2 are as defined above in the presence of a substance yielding the cation M or by additively combining sulphur with a compound of the general formula <FORM:0805931/IV (b)/3> in which R1, R2 and M are as defined above. The radical R1 may be aliphatic, especially a C1-C4 alkyl radical, or a cycloaliphatic radical, and the radical R2 may be heterocyclic, araliphatic, aliphatic or cycloaliphatic.  The aliphatic radicals which R2 may represent may be saturated or unsaturated and may have a straight or branched chain and may be substituted or unsubstituted, specified radicals being ethyl, propyl, isopropyl, butyl, hexyl, 2-ethyl-butyl, octyl, 2-butyloctyl, dodecyl, octadecenyl, octadecyl or allyl or a radical containing a thiocyano, cyano, or ether group or a halogen atom, e.g. the 2-chloroethyl radical. Other specified radicals which R2 may represent are benzyl, cyclohexyl, and tetrahydrofurfuryl.  Preferred dialkyl phosphites are those in which R1 is a C1-C4 alkyl radical and R2 is a C8-C30 alkyl radical. Specified substances yielding the cation M are alkali metals, alkali metal alcoholates, alkali metal carbonates or bicarbonates, ammonia, and amines such as dimethylamine or monoethylamine.  The reaction with sulphur is preferably carried out in the presence of an organic solvent.  When an alkali metal is used as the substance yielding the cation M it is an advantage to use benzene, toluene or xylene as solvent.  With the other substances yielding the cation M the solvent is advantageously an alcohol, e.g. methyl, ethyl, or isopropyl alcohol.  The reaction may be carried out at ordinary or raised temperature, e.g. at 30-100 DEG  C., and the sulphur is usually added in the theoretical quantity.  Any excess sulphur used may be removed by filtration.  Examples are given for the production of the ammonium sodium, potassium, and dimethylamine salts of dodecyl ethyl thiophosphoric acid, the ammonium salt of octadecyl methyl thiophosphoric acid, the potassium and sodium salts of dodecyl methyl thiophosphoric acid, and the potassium salt of octadecenyl methyl thiophosphoric acid, isooctyl methyl thiophosphoric acid, isoamyl methyl thiophosphoric acid, isobutyl methyl thiophosphoric acid, cyclohexyl ethyl thiophosphoric acid, benzyl ethyl thiophosphoric acid, and tetrahydrofurfuryl ethyl thiophosphoric acid respectively. Dodecyl ethyl thiophosphoric acid precipitates out on adding sulphuric acid to the ammonium salt.  Some of the products can be used as assistants in the textile, leather, or paper industry, e.g. as washing agents (see Group IV (c)), wetting-agents, or foaming agents, as additives for oils or lubricants or as constituents of paints.  The asymmetrical diesters of phosphorous acid used as starting materials may be obtained by transesterification of symmetrical phosphites and detailed examples are given for the production of dodecyl ethyl phosphite from lauryl alcohol and diethyl phosphite and of octadecenyl methyl phosphite from oleyl alcohol and dimethyl phosphite.  Specification 685,737 is referred to.ALSO:The potassium salt of dodecyl ethyl thiophosphoric acid (see Group IV (b)) may be used as a washing agent.  In Example II, greasy wool is treated a number of times with an aqueous solution of the salt.