Adducts of silyl, germyl and stannyl radicals with heterocyclic ?-diketones: an electron spin resonance investigation

Hyperfine coupling constants are reported for adducts of silyl, germyl and stannyl radicals with a series of substituted benzo [b]thiophen-2,3-diones (Ia-Ip), benzo [b] furan-2,3-dione (II), ninhydrin (III), and thieno [ 3,2-b] thiophen-2,3-dione (IV). The conformational and electronic properties of these radicals are compared with those of similar adducts formed by diaryl ketones. © 1979.