X-BAND CIDNP-DETECTED ESR-SPECTRUM IN HYDROGEN ABSTRACTION REACTION OF CARBONYL-COMPOUNDS

CIDNP-detected ESR (SNP and DNP), ESR, and CIDEP spectra are observed in the system of hydrogen abstraction reaction of 2,6-dichlorobenzoqui none. These spectra show the existence of two different intermediate r adicals. One radical (radical 1) is p-(hydroxy)-2,6-dichloro-phenoxyl radical, and it appears as SNP. The other radical (radical 2) is p-hyd roxy-3,5-dichloro-phenoxyl radical, and it appears in DNP, ESR, and CI DEP spectra. These results show that radical 1 exists as a component o f radical pair, and radical 2 exists as a free radical. The possibilit y of hydrogen transfer or hydrogen exchange reaction from radical 1 to radical 2 is discussed.