RADICAL-ANIONS OF DIALANE [R2AL-ALR2]-

Tetrakis[bis(trimethylsilyl)methyl]dialane(4) (1) with-an Al-Al bond r eacts with sodium or potassium in 1,2-dimethoxyethane to yield dark bl ue radical monoanions [R2Al-AlR2].-, which are quite persistent after recrystallization and can be characterized speCtroSCopically (ESR, UV- VIS, IR) as pi-radicals. Surprisingly, similar compounds are formed by the single electron transfer reaction of 1 with neopentyl- or trimeth ylsilylmethyl-lithium in the presence of the chelating N,N,N',N'-tetra methylethylenediamine. diamine.