Hydrogen peroxide-Phenyl isocyanate

With phenyl isocyanate 48 yields the 3-anilinoformyl derivative while with sulfuric acid followed by sodium hydroxide it is converted via 64 into 49.39 Although 48 is catalytically reduced to 47 it is recovered unchanged from treatment with sodium in ethanol or lithium aluminum hydride. Treatment of 47 with hydrogen peroxide and sodium hydroxide gave a dihydrodiazepine believed to be 65 which is isomerized to 48 with acid. Finally, condensation of 47 with formaldehyde gave rise to 66.39... 

CYCLOADDITION N-Alkylhydroxy-lamines. f-Butyldimethylsilyl ethylnitron-ate. Cyclopropenone 1,3-propanediyl ke-tal. Hydrogen peroxide-Sodium tungstate. N-Methylhydroxylamine. Phenyl isocyanate. Trimethylamine N-oxide. Trimethylsi-lylmethyl azide. 

The yields of epoxides are 35-70% the yields of 1,3-diphenylurea are 92-98%. Yields of epoxides are improved by use of nonpolar solvents such as n-pentane or benzene. p-Chlorophenyl isocyanate gives somewhat higher yields than phenyl isocyanate. The active intermediate is probably an isocyanate-hydrogen peroxide complex rather than a peroxycarbamic acid (CgHsNHCOgH).1 N. Matsumura, N. Sonoda, and S. Tsutsumi, Tetrahedron Letters, 2029 (1970)... 

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