Table 3.

Absorption and kinetic properties of N-ethylheterocycle radicals in acetonitrile at room temperature.

Radical Structure*	Radical Precursor†	λmax‡ (nm)	kq•(O2)§ (M−1 s−1)
	6E	510	3.3 × 107
	7E	700	7.3 × 108
	3E	575	4.3 × 108

^*Several other resonance contributors can be drawn;

^†Studied as either the tetrafluoroborate or hexafluorophosphate salts;

^‡Approximate absorption maximum of the radical;

^§Rate constant for radical reaction with molecular oxygen.