LIMITATIONS ON THE PERSISTENCE OF IMINOXYLS - ISOLATION OF TERT-BUTYL1,1-DIETHYLPROPYL KETIMINOXYL AND RELATED RADICALS

A series of iminoxyl radicals of the general formula R(C=NO.)R(1), wit h R and R(1) usually tertiary, was synthesized in a search for radical s of increased persistence. Three new radicals were isolated as blue L iquids: Et(3)C(C=NO.)Bu-t (1), t-C5H11(C=NO.)Bu-t (2), and (t-C5H11)(2 )C=NO. (3). Oxidation of oximes Et(3)C(C=NOH)Ph (4H), PhCH(2)CMe(2)(C= NOH)Bu-t (5H), PhCMe(2)(C-NOH)Bu-t (6H), and Me(2)CH(C=NOH)C5H11-t (7H ), among others, did not lead to isolable iminoxyls. A new, convenient synthesis of symmetrical tertiary imines from tert-RCl, tert-RCN, and Na is described, Radical t-Bu(2)C=NO. (8) and cyclohexene readily gav e the allylic substitution product, 2,2,4,4-tetrametftyl-3-hexanone O- (2'-cyclohexen-1'-yl)oxime.