Preparation of acylisoxazolines

A method of preparing an acylisoxazoline or mixtures thereof corresponding to the formula:

• ##STR3## where R is an alkyl group having from 2 to 20 carbon atoms which comprises contacting a 1-alkene, or mixtures thereof, of the formula R--CH.dbd.CH.sub.2 with dinitrogen tetroxide and oxygen in the presence of a denitrating agent that consists of one or more compounds selected from ##STR4## where R.sup.1, R.sup.2, R.sup.6, R.sup.7, R.sup.8, R.sup.9 and R.sup.10 are alkyl of from 1 to 5 carbons and R.sup.3, R.sup.4, R.sup.5, R.sup.11, R.sup.12, and R.sup.13 are hydrogen or alkyl of from 1 to 5 carbons and calcium oxide at a temperature of about -10.degree. to 40.degree. C., wherein the mole ratio of alkene to dinitrogen tetroxide to oxygen is from about 1:0.02:0.04 to 1:0.4:30 and the mole ratio of dinitrogen tetroxide to denitrating agent to calcium oxide is from about 1:0.5:0.5 to 1:5:5.