Patent GB-786601-A (GB)
Title: Production of heterocyclic dithiophosphoric esters
IPC: C07F9/6571
Filed: 1956-01-11
Abstract: The invention comprises heterocyclic phosphorus-containing esters having the formula: <FORM:0786601/IV (b)/1> wherein R, R1, R2, R3, R4 and R5 designate a hydrogen atom or an alkyl radical; m is 0 or 1, Z is a -CN or a -OOCR6 radical wherein R6 is a hydrogen atom or a saturated or olefinically unsaturated aliphatic hydrocarbon radical, or a monocyclic aromatic hydrocarbon radical, or a halogen-substituted aliphatic, or a halogen-substituted aromatic hydrocarbon radical and n is 0 or 1.  They may be obtained by reacting at a temperature between - 20 DEG  C. and about 150 DEG  C. a heterocyclic phosphorus-containing acid of the formula: <FORM:0786601/IV (b)/2> wherein the various R groups are as defined above with an alkenyl ester of the formula CH2 = CH(CH2)nZ wherein n and Z are as defined above.  The reaction can be carried out in the presence of a small amount of a condensation catalyst such as an aliphatic tertiary amine, e.g. triethylamine, or an alkali metal hydroxide or carbonate.  A polymerization inhibitor such as hydroquinone may also be present and it is preferred to carry out the reaction in the presence of an inert organic solvent or diluent, e.g. a saturated fatty acid ester such as ethyl-, amyl- and 2-ethylhexyl acetates, methyl propionate, and methyl and ethyl butyrates, a ketone such as acetone or methyl isobutyl ketone, an ether such as dioxane, an aromatic compound such as benzene, toluene, a xylene, chlorobenzene or nitrobenzene; chloroform, a trialkyl phosphate, e.g. triethyl- and tri-(2-ethylhexyl) phosphates, or a saturated nitrile such as acetonitrile or propionitrile.  Specified heterocyclic dithiophosphoric acids which may be used as starting materials are 2 - mercapto - 2 - thiono - 1,3,2 - dioxaphosphorinane and the 4 - ethyl -, 4 - butyl -, 4-(2 - ethyl - hexyl) -, 4 - tetradecyl -, 5 - ethyl -, 5 - butyl -, 5 - decyl -, 5 - heptadecyl -, 4,5 - diethyl -, 4 - methyl - 5 - ethyl -, 4,5 - dibutyl -, 4 - propyl - 5 - tetradecyl, 5 - ethyl - 5 - butyl -, 5,5 - dibutyl -, 5 - butyl - 5 - dodecyl, 4,4,6 - trimethyl -, and 4,4,5,5 - tetramethyl substituted 2 - mercapto - 2 - thiono - 1,3,2 - dioxaphosphorinanes and the corresponding substituted and unsubstituted 2-mercapto-2-thiono-1,3,2-dioxaphospholanes. Specified alkenyl esters which may be used are the vinyl and allyl esters of hydrocyanic acid and of fatty acids such as formic, acetic, propionic, butyric, caproic, 2-ethyl hexanoic, capric, and stearic acids, or of halogen-substituted fatty acids such as the chloro and bromo acetic, propionic and butyric acids; and of oleic acid, benzoic acid and the o-, m- and p-chloro substituted and o-, m-, and p-alkyl substituted benzoic acids.  Examples are given for the production of (1) 2 - (2 - acetoxyethylmercapto) - 5,5 ethyl - 2 - thiono - 1,3,2 - dioxaphosphorinane; (2) 2 - (2 - acetoxyethylmercapto) - 5 - ethyl - 4-propyl-2-thiono-1,3,2-dioxaphosphorinane; (3) 2 - (2 - acetoxyethylmercapto) - 2 - thiono-4,4,6 - trimethyl - 1,3,2 - dioxaphosphorinane; (4) 2 - (2 - chloroacetoxyethylmercapto) - 5,5-diethyl - 2 - thiono - 1,3,2 - dioxaphosphorinane; (5) to (8) 5,5 - diethyl - 2 - (2 - oleoyloxyethyl mercapto) - 2 - thiono - 1,3,2 - dioxaphosphorinane, and the corresponding (2-ethylhexanoyloxy -), (2 - octadecanoyloxy -) and (2-benzoyloxy -) compounds respectively; (9) 2-(2 - cyanoethylmercapto) - 5 - methyl - 2 - thiono-1,3,2 - dioxaphospholane; (10) 2 - (2 - cyanoethyl mercapto) - 5 - ethyl - 4 - propyl - 2-thiono - 1,3,2 - dioxaphosphorinane, and (11) 2 - (2 - cyanoethylmercapto) - 2 - thiono - 4,4,6-trimethyl - 1,3,2 - dioxaphosphorinane.  The products are stated to be useful as pesticides (e.g. in aqueous suspension), as plasticizers for synthetic resins, and as corrosion inhibitors, flotation agents, and petroleum additives.  Specification 759,334 is referred to.