Patent GB-919785-A (GB)
Title: Insect repellent compositions comprising sulphoxides and methods of repelling insects therewith
Inventor: LOUTHAN RECTOR PHILIP
IPC: A01N41/10
Filed: 1960-03-21
Abstract: Sulphoxides of the formula:- p   <FORM:0919785/IV (b)/1> wherein R1 is an unsaturated alicyclic or acyclic hydrocarbon radical containing at least one ethylenic or acetylenic bond and having 3 to 10 carbon atoms, wherein R2 is the same radical as R1 or is a saturated or unsaturated aliphatic or alicyclic radical having 3-20 carbon atoms or one of either of these radicals in which a hydrogen atom is replaced by <FORM:0919785/IV (b)/2> and wherein the total number of carbon atoms in the compound is in the range 6-30 are prepared by oxidising the corresponding sulphide in a solvent e.g. acetic acid, acetone or methanol at a temperature of 0 DEG -200 DEG C. employing hydrogen peroxide, peracids, nitric acid, chromic acid or potassium permanganate as oxidising agent.  The sulphoxides are used as insect repellents (see Group VI).  In examples are prepared: (1) allyl n-octyl sulphoxide from the corresponding sulphide obtained from allyl bromide and n-octyl mercaptan; (2) a mixture of allyl 2-(3-cyclohexenyl)-ethyl and alkyl 3- and 4-vinylcyclohexyl sulphoxides from the corresponding sulphide mixture from reacting allyl bromide with a reaction product comprising b -mercapto-ethylcyclohexene-3 and 1-vinyl-3- and -4-mercaptocyclohexanes from 4 - vinylcyclohexene and H2S under U.V.; (3) a mixture of allyl 3- and 4-(2-allylsulphinylethyl)cyclohexyl sulphoxides from the corresponding sulphide mixture obtained by the action of allyl bromide on a mixture of b -mercaptoethyl-3-and -4-mercaptocyclohexanes from 4-vinyl-cyclohexene and H2S under U.V.; (4) a mixture of 2-(3-cyclohexenyl)ethyl n-octyl and 3-and 4-vinylcyclohexyl n-octyl sulphoxides from the corresponding sulphide mixture obtained by 4-vinylcyclohexene and n-octyl mercaptan under U.V.; (5) allyl 5-cyclooctenyl sulphoxide from the corresponding sulphide prepared from allyl bromide and 4-cyclooctene-1-thiol; (6) 5,51-bis(cyclooctenyl)sulphoxide from the corresponding sulphide obtained from 1,5-cyclooctadiene and H2S under U.V.; and (7) a mixture comprising bis[2 - (3 - cyclohexenyl) ethyl], bis(3-vinylcyclohexyl), bis(4-vinylcyclohexyl)sulphoxides and 3- and 4-vinylcyclohexyl 2(3-cyclohexenyl)ethyl sulphoxides from the corresponding sulphide mixture obtained from 4-vinylcyclohexene (2 mols) and H2S (1 mol) under U.V.  Many other sulphoxides are named.ALSO:The invention relates to a method of repelling insects from a locus otherwise frequented by the same which consists of applying to or in the vicinity of, such locus an insect repelling agent comprising one or sulphoxides of the formula <FORM:0919785/VI/1> wherein R1 is an unsaturated alicyclic or acyclic hydrocarbon radical containing at least one ethylenic or acetylenic bond and having 3-10 carbon atoms, wherein R2 is the same radical as R1 or is a saturated or unsaturated aliphatic or alicyclic radical having 3-20 carbon atoms or one of either of these radicals in which a hydrogen atom is replaced by <FORM:0919785/VI/2> and wherein the total number of carbon atoms in the compound is in the range 6-30. An insect-repellent composition for use in said method comprises a carrier and a mixture selected from the mixtures comprising allyl 2 - (3 - cyclohexenyl) - ethyl sulphoxide, allyl 3-(vinylcyclo hexyl) sulphoxide and allyl 4-(vinylcyclohexyl) sulphoxide; allyl 3-(2-allyl-sulphinyl ethyl) cyclohexyl sulphoxide and allyl 4-(2-allylsulphinyl ethyl) cyclohexyl sulphoxide; 2 - (3 - cyclohexenyl) ethyl n - octyl sulphoxide, 3 - vinylcyclohexyl n - octyl sulphoxide and 4-vinyl cyclohexyl n-octyl sulphoxide; and bis {2 - (3 - cyclohexenyl) ethyl} sulphoxide, bis {3-vinylcyclohexyl} sulphoxide, bis {4-vinyl cyclohexyl} sulphoxide, 4 - vinyl cyclohexyl - 2 (3-cyclohexenyl) ethyl sulphoxide and 3-vinyl-cyclohexyl-2 (3-cyclohexenyl) ethyl sulphoxide; or one or more sulphoxides of the formula <FORM:0919785/VI/3> wherein R1 is as above and R2 is a saturated or unsaturated aliphatic or alicyclic radical having 3-20 carbon atoms and the total number of carbon atoms in the compound is 6-30; or one of propargyl n-octyl sulphoxide, 5,51 bis (cyclo octenyl) sulphoxide, 5-cyclo octenyl n-octyl sulphoxide or allyl 5-cyclo octenyl sulphoxide.  The sulphoxides may be applied in the form of solutions in organic solvents e.g. naphthas, kerosene, toluene, xylene, cyclohexanone, acetone or isoparaffinic hydrocarbons which are brushed on or used as sprays or mixed with a propellent for use as an aerosol. The sulphoxides may be blended with wax polishes, sorbed on clays or made up as wettable powders or emulsions.  A specified emulsifier is an ethylene oxide condensate of nonyl phenol. The sulphoxides may be applied together with insecticides, e.g. rotenone, (N - {2 - ethyl hexyl}) bicyclo-(2,2,1) - 5 - heptene - 2,3 - dicarboximide, methoxychlor, dieldrin, lindane, chlordane, nitropyridine, N-oxide of nitropyridine, pyrethrum extracts together with a synergist e.g. piperonyl butoxide or piperonyl cyclonene or its 6-carbethoxy derivatives, or esters of phosphoric and thiophosphoric acids.  Additional insect repellents may be used. Numerous examples of sulphoxides are given.