Patent GB-945770-A (GB)
Title: Aldehydes and method of preparation
IPC: C07C47/20
Filed: 1960-03-16
Abstract: The invention comprises compounds of the formulae: <FORM:0945770/C2/1> <FORM:0945770/C2/2> <FORM:0945770/C2/3> <FORM:0945770/C2/4>  in which R2 is a C1-C11 alkyl group, R3 is a C1-C18 alkyl group, A is an aryl group, R4 is a C1-C6 alkyl group and n is 8-11, and isomers of these in which the formyl, hydroxyl and vinylene hydrogen are interchanged.  These and some known aldehydes may be prepared by treating certain 1,2-epoxides with carbon monoxide and hydrogen at elevated temperature and pressure in the presence of a hydroformylation catalyst.  The 1,2-epoxides which may be used as starting materials have the following formulae: <FORM:0945770/C2/5> , <FORM:0945770/C2/6> or <FORM:0945770/C2/7> in which R and R1 are hydrogen or alkyl groups and R2, R3, R4 and n are as defined above. The preferred pressure range for the process is 900-10,000 psi. and the preferred temperature range is 120-150 DEG C.  The reaction may be carried out in the presence of one or more inert organic volatile solvents.  Suitable catalysts are, for example, oil-soluble salts of iron, cobalt and nickel, and the catalyst may be supported on a carrier material. The aldehyde products are generally mixtures of b -hydroxy aldehydes and a ,b -unsaturated aldehydes and their isomers. Higher yields of the unsaturated aldehydes may be obtained by continuing heating of the products in the presence of water and an acidic catalyst. In the examples: (a) propylene oxide is converted to methacrolein and crotonaldehyde; (b) 1, 2-epoxyoctane is converted to a - and b -n-hexylacrolein; (c) 1, 2-epoxyhexane is converted to a - and b -n-butylacrolein; (d) 9, 10-epoxystearate is converted to a mixture of methyl-9-hydroxy-10, formylstearate and methyl-9-formyl oleate and their isomers in which the formyl group is interchanged with the hydroxy group or 10-hydrogen atom; (e) ethyl-9, 10-epoxy-stearate is converted to ethyl-9-hydroxy-10-formyl stearate and ethyl-9-formyl 9-formyl oleate and their isomers; (f) octyl-9, 10-epoxy-stearate is converted to octyl-9-hydroxyformyl stearate and octyl-9-formyl oleate and their isomers; (g) methyl-13,14-epoxylbehenate is converted to methyl-13-hydroxy-14-formyl docosanoate and methyl-15-formyl erucate and their isomers; (h) 1-phenyl-2,3-epoxybutane is converted to 2-methyl-3-hydroxy-4-phenyl butanal and 2-methyl-4-phenyl-2-butenal and their isomers; and (j) 1-xylyl-2, 3-epoxyhexane is converted to 2-methyl-3-hydroxy-4-xylyl butanal, 2-(2,41-dimethyl-benzyl)-3-hydroxy-butanal, 2-methyl-4-xylyl-2-butenal and 2-(2,41-dimethylbenzyl)-2-butenal.ALSO:Unsaturated aldehydes of formula <FORM:0945770/A5-A6/1> or <FORM:0945770/A5-A6/2> in which R2 is a C1-C11 alkyl group, R3 is a C1-C18 alkyl group, A is an aryl group and R4 is a C1-C6 alkyl group, and n is 8-11, and their isomers in which the aldehyde group and the hydrogen atom attached to the unsaturated carbon atom are interchanged, may be used as additives in insect-repellents or sun tan lotions.  An example is given of an insect repellent composition containing dimethyl phthalate, a non-ionic water soluble surface active agent, e.g. an alkylphenoxypolyethoxyethanol condensate containing 12 ethyleneoxy units, mineral oil, water and one of the aldehydes of the invention. A sun tan lotion may be prepared containing anhydrous lanolin and methyl salicylate in addition to the above ingredients.