NMR SILENT, NATURALLY-OCCURRING QUINONES - A CASE OF RADICALS

Citation
Sj. Gould et Cr. Melville, NMR SILENT, NATURALLY-OCCURRING QUINONES - A CASE OF RADICALS, Tetrahedron letters, 38(9), 1997, pp. 1473-1476
Citations number
11
Categorie Soggetti
Chemistry Inorganic & Nuclear
Journal title
ISSN journal
00404039
Volume
38
Issue
9
Year of publication
1997
Pages
1473 - 1476
Database
ISI
SICI code
0040-4039(1997)38:9<1473:NSNQ-A>2.0.ZU;2-J
Abstract
Kinobscurinone, a benzo[b]fluorenone quinone previously reported to be ''NMR silent,'' affording neither H-1- nor C-13 NMR spectra under a v ariety of conditions, has now been shown to exist in part as a free ra dical under ambient conditions. The g value for kinobscurinone was fou nd to be 2.0052; no hyperfine splitting was observed. ESR signals were similarly observed for three other substituted benzo[b]fluorene quino nes. (C) 1997 Elsevier Science Ltd.