The reaction between nitric oxide and triphenylmethyl radi- cal has been described by Schlenk, Mair and Bornhardt [1], howe- ver they failed to isolate the reaction product which they assumed to be the nitrosotriphenylmethane. Hinshelwood et al. [2] have found some kintetic evidences of the direct combination of free metliyi radical with nitric oxide to form nitrosomethane, however this compound has never been isolated. Much later, Raley? Rust and Vaughan [3] have shown that the first stable product of this reaction is formaldoxime which is the tautomer of nitrosomethane. In the sequence of the reaction further attack of methyl radicals gave a complex reaction product. Gingras and Waters [4] have examined the reaction hetween nitric oxide and inoderately reac-: tive 2-cyano-2-propyl free radical, which was produced by deeom- position of azo-bis-isobutyronitrile in boiling benzene and N, N, O-tri substituted hydroxylamine derivative was obtained. Waters and his coworkers [5] have reacted nitrogen dioxide with a, a' azo-bis-isobutyronitrile and obtained nitro-isobutyronitrile. Cain and Visologle [6] have studied the reaction between nitric oxide » and diphenylnitrogene radical which is produced by heating of.