Patent GB-813539-A (GB)
Title: Improvements in the production of organic compounds with aliphatic conjugated unsaturated linkages
IPC: C07C45/51
Filed: 1955-09-21
Abstract: A process for the production of organic compounds with aliphatic conjugated unsaturated linkages comprises adding to a phosphine ylide of the general formula: <FORM:0813539/IV (b)/1> in which each R represents an aryl group, R1 represents hydrogen or an aliphatic group and R11 represents hydrogen, a saturated or unsaturated aliphatic, cycloaliphatic, cycloaliphatic-aliphatic, araliphatic or aromatic radical or the radical <FORM:0813539/IV (b)/2> R111 representing the link between the two carbon atoms adjacent to the phosphorus which link consists of at least one atom, R1111 being hydrogen or alkyl, or R1 and R11 jointly with the C to which they are attached represent a cycloaliphatic radical, wherein each of the radicals R1, R11 and R111 can bear indifferent groups, such as ester groups, nitrilo groups, and amide groups, ether groups and aromatically bound halogen, about the equivalent amount of a saturated or unsaturated carbonyl compound whereby a product of the general formula: <FORM:0813539/IV (b)/3> is formed, X being the radical originating from the carbonyl compound and R1 and R11 having the meaning given above except that when bisylides are reacted R11 is <FORM:0813539/IV (b)/4> R111 and R1111 having the meaning given above, with the proviso that the system of aliphatic conjugated unsaturated linkages exists at least in one of the radicals R1 or R11 or in the carbonyl compound or is formed by the reaction of the phosphine ylide with the carbonyl compound.  The phosphine ylides employed as starting materials may be prepared by reacting triphenyl, tritolyl or diphenyltolyl phosphines with organic halides such as methyl, ethyl, allyl, cyclohexyl, diphenylmethyl, cinnamyl, geranyl, cyclogeranyl, a - and b -ionyl or propargyl bromides, methoxybenzyl or chlorbenzyl chlorides, chloracetic acid esters, chloracetaldehyde diethyl acetal or chloro-acetonitrile, monochlorethyl ether and chloracetamide, dibrompropane or butane or 1 : 4-dichlorobutene-(2) preferably by heating equivalent amounts of reactants e.g. in ethers or hydrocarbons as solvents, to obtain quaternary phosphonium salts and treating the latter with hydrogen halide removing reagents which do not form water in the reaction, e.g. methyl, phenyl, butyl or tolyl lithium phenyl, ethyl or tertiary butyl magnesium halides, an alkali metal, e.g. sodium, acetylide, an alkali metal amide, or alkali metal or alkaline earth metal alcoholates.  Solvents mentioned for use in the ylide forming reaction are ether, tetrahydrofurane and dioxane, preferably in an oxygen-free atmosphere.  Carbonyl compounds mentioned in addition to those employed in the examples include acetaldehyde, cyclohexanone, acetophenone, p,p1-tetramethyldiaminobenzophenone, p,p1-dinitrobenzophenone, propargyl aldehyde, butine-(1)-one-(3), pseudoionone, camphor, ethyl acetoacetate, acetol, furfural, pyridine aldehydes and ketones, dialdehydes and diketones, e.g. glyoxal, maleic and succinic dialdehydes, adipaldehyde, terephthal- and isophthal-aldehydes, bromomalonic dialdehyde, acetyl-acetone, acetonyl acetone, benzoyl-acetone, di-benzoyl methane, 4.9 - dimethyldodecapentaene - (2.6.7.8.10) diol (1.12), 2,7 - dimethyloctadien - (3.5) dione-(2.7) and 2.7-dimethyl octaene-(4)-dione (2.7).  The reaction of the phosphine ylide and aldehyde or ketone may be carried out with cooling, the intermediate product decomposed by heating and the reaction product worked up, after removal of phosphine oxide, by chromatography and or distillation or recrystallisation.  In examples: 1-phenylbutadiene-(1.3) is obtained by reacting triphenylphosphonium vinyl methylide with benzaldehyde (1); 1.4-diphenylbutadiene is obtained by reacting triphenylphosphonium benzylide with cinnamaldehyde (2-4); 1 - 10 - diphenyl - 3.8 - dimethyl - decapentaene - (1.3.5.7.9) is obtained by reacting 2.7 - dimethyloctadiene - (2.6) - dial - (1.8) with triphenylphosphonium benzylide (5); 1.10-bis-(21.61.61 - trimethylcyclohexene (11) - yl - (11)-3.8 - dimethyl - decatetraene (1.3.7.9) ine (5) is obtained by reacting 2.7-dimethyloctadiene (2.6)-ine (4)-dial (1.8) with triphenyl phosphonium beta - cyclogeranylide (6); 11,12-dehydroaxerophthene is obtianed by reacting beta - ione with triphenylphosphonium 4-methyl - hexene - (2) - ene - (4) - ylide (1) and may be converted by hydrogenation to axerophthene (7); 1.10-diphenyldecapentaene is obtained by reacting cinnamaldehyde with the bis-ylide obtained by treating 2-butene-1.4-bis-(triphenylphosphonium) chloride with phenyl lithium (8); 1.4-diphenylbutadiene is obtained by reacting triphenyl phosphonium benzylide with cinnamaldehyd (9-11); 1-phenyl-2-methyl propylene and 1,2,2-triphenylethylene are similarly obtained using acetone and benzophenone (11); cinnamalacetic acid ethyl ester, beta - methyl - beta - hydroxy - methylacrylic acid ethyl ester, sorbic ester, beta, beta-dimethyl acrylic acid ethyl ester and beta-methylglutaconic acid diethyl ester are obtained by reacting cinnamaldehyde, acetol, crotonaldehyde, acetone, ethylacetoacetate with carbethoxy methylene triphenylphosphine (12); cinnamalacetonitrile and beta-ionyl-idene acetonitrile respectively are obtained by reacting cinnamaldehyde and betaionone with cyanomethylene triphenylphosphine (13); sorbic acid amide is obtained by reacting carbamidoethylene triphenylphosphine or its alcohol addition product with crotonaldehyde (14); 1,10-bis - (21.61.61 - trimethylcyclohexane - (11) - yl-) 3.8 - dimethyldecapentaene (1.3.5.7.9) is obtained by reacting 2.7-dimethyloctatrien (2.4.6)-dial-1.8 with betacyclogeranyl triphenylphosphine (15); isomeric beta carotenes, which may be converted into all-trans-beta carotene by boiling the solution with a trace of iodine, are obtained by reacting triphenylphosphonium-beta ionylide with 4.9-dimethyldodecapentaene-(2.4.6.8.10)-dial-(1.12), (16); trans Vitamin A acid methyl ester, which is saponified to obtain the corresponding free acid, is obtained by reacting beta-ionylideneacetaldehyde with the product obtained by reacting gamma-bromomethyl crotonic acid methyl ester with triphenyl phosphine and treating the product with sodium ethoxide solution (17); and 15, 151-dehydrobeta-carotene is obtained by reacting 2.7-dimethyloctadiene - (2.6) - ine - (4) - dial - (1.8) with the phosphonium ylide obtained by reacting beta-ionylidene ethanol with phosphorus tribromide, reacting the product with triphenyl phosphine and treating the phosphonium halide with a solution of sodium in ethanol; the product being optionally converted to betacarotene by treatment with iodine (18).  2.7 - Dimethyloctatrien - (2.4.6) - diol - (1.8) is obtained by reacting maleic dialdehyde tetraethyl lacetal with propenyl ethyl ether, neutralizing and distilling the product to obtain 2.7-dimethyl-1.1.3.6.8-8-hexaethoxyoctaene and heating the latter with p-toluene sulphonic acid.  4.9 - Dimethyldodecapentaene - (2.4.6.8.10) dial - (1.12) is obtained by heating the above product with ethyl orthoformate and ammonium nitrate to obtain 1.1.8.8-tetraethoxy 2.7-dimethyloctatriene which is reacted with vinyl ethyl ether and heating the product with p-toluene sulphonic acid.