Patent GB-735974-A (GB)
Title: Improvements in the epoxidation of ethylenically unsaturated organic compounds
Filed: 1953-08-04
Abstract: Ethylenic compounds as defined below are converted into the corresponding epoxides by reaction with an acetaldehyde mono-peracylate or propionaldehyde mono-peracylate at about 25-200 DEG  C.  Preferably a cold solution of the mono-peracylate is fed intermittently or continuously into a heated reaction chamber at 40-120 DEG  C. containing the ethylenic compound or solution thereof, the reaction then occurring in the liquid or vapour phase.  It is desirable to use more than the theoretical quantity of ethylenic compound and to remove as fast as it is formed the aldehyde and acid resulting from decomposition of the mono-peracylate.  The ethylenic compound is one having the following characteristics: (1) having at least three carbon atoms; (2) containing no element other than carbon, hydrogen, oxygen, halogen, nitrogen (as amide, imide or nitrile) or phosphorus (as phosphoric ester), and (3) having attached to the >C=C< group only hydrogen or carbon not multiply linked to elements other than carbon or hydrogen; mesityl oxide is however included.  A polymerization inhibitor may be added if desired. Examples show the preparation of epoxides of propylene, butadiene, styrene, 4-vinylcyclohexene and its monoxide, allyl alcohol, mesityl oxide, oleic acid, soybean oil, methallyl chloride, oleamide, D 3-tetrahydrobenzonitrile and N-(n-butyl)-D 3-tetrahydrophthalimide. A list is given of other ethylenic compounds, of the following types: alkenes, alkadienes, alkenylbenzenes, cycloalkenes, cycloalkadienes, indene, dihydronaphthalene, methylenecyclohexane, alkenyl chlorides, bromides and fluorides, chlorostyrenes, chloromethylstyrenes, 1 - chloro - 3 - vinylcyclohexane, trichloromethyl - cyclohexene, alkenols, cinnamyl alcohol, cyclohexenylmethanol, alkenylphenols, methylenecyclohexanol, alkenyloxy compounds, cyano-alkenes, vinylbenzonitriles, unsaturated ketones, acids and esters (including glycol dioleate and diallyl maleate), p-vinylbenzaldehyde, unsaturated amides, vinylbenzamides, N - alkenyl - imides, acetals of unsaturated aldehydes (including p-vinylbenzaldehyde), acetaldehyde diallyl acetal, alkenyl phosphates and tri-(crotylphenyl) phosphate. Acetaldehyde monoperacetate CH3CH(OH) OOCOCH3 is prepared by treating acetaldehyde with an oxygen-containing gas below 15 DEG  C., preferably in a solvent.  Salts of heavy metals such as cobalt, copper and iron are catalysts for the reaction, but excess tends to decompose the peroxide to acetic acid.  Propionaldehyde monoperpropionate is made similarly.  Experimental details are given in each case.ALSO:Ethylenic compounds, including unsaturated oils such as soybean oil and linseed oil, are converted into the corresponding epoxides by reaction with an acetaldehyde mono-peracylate or propionaldehyde mono-peracylate at about 25-200 DEG  C.  Preferably a cold solution of the mono-peracylate is fed intermittently or continuously into a heated reaction chamber at 40-120 DEG  C. containing the ethylenic compound or solution thereof. It is desirable to use more than the theoretical quantity of ethylenic compound and to remove as fast as it is formed the aldehyde and acid resulting from decomposition of the mono - peracylate. Examples show the epoxidation of soybean oil with acetaldehyde mono-peracetate and propionaldehyde mono-perpropionate.