Limitations on the Persistence of Iminoxyls: Isolation of tert-Butyl 1,1-Diethylpropyl Ketiminoxyl and Related Radicals.
A series of iminoxyl radicals of the general formula R(C=NO(*))R(1), with R and R(1) usually tertiary, was synthesized in a search for radicals of increased persistence. Three new radicals were isolated as blue liquids: Et(3)C(C=NO(*))Bu-t (1), t-C(5)H(11)(C=NO(*))Bu-t (2), and (t-C(5)H(11))(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)C(5)H(11)-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 gave the allylic substitution product, 2,2,4,4-tetramethyl-3-hexanone O-(2'-cyclohexen-1'-yl)oxime.
Eisenhauer
Brian M.
BM
Department of Chemistry, Michigan Technological University, Houghton, Michigan 49931-1295.
Wang
Minghui
M
Labaziewicz
Henryk
H
Ngo
Maria
M
Mendenhall
G. David
GD