Rajive K. Khanna

The reaction of carbanions with tert-Butyl radicals

Abstract The SRN1 free radical chain reaction of Me3CHgCl with nitronate (−O2NC(R1)(R2)) and phenone enolate (PHC(0−)C(R1)(R2)) anions yields the C-alkylation products (Me3CC(R1)(R2)N02, PhCOC(R1)(R2)CMe3). Competitive reactions between pairs of anions demonstrate that as the basicity of the anion increases the reactivity toward Me3C at first increases and then decreases. An inverted reactivity order is also observed with phenylacetonitrile anions. In early transition state reactions, the nucleophilic character of the tert -butyl radical apparently controls the reactivity by virtue of a transition state involving transfer of the electron from radical to the LUMO of the resonance stabilized anion.

ELECTRON-TRANSFER PROCESSES. PART 40. REACTION OF ALKYL RADICALS WITH DIPHENYLPHOSPHIDE ANION

Abstract The anion Ph2P− (K+, 18-crown-6) reacts with t-BuHgCl in HMPA to form Ph2PCMe3 by a free radical chain mechanism. In Me2SO, Ph2P(O)CMe3 is produced. Reaction of Ph2P− with PhCOCH2HgCl yields the oxidative dimerization product isolable from HMPA but readily converted to Ph2P(O)P(O)Ph2 in Me2SO.

Free radical reactions of 1,1-diarylethylenes with t-butylmercury chloride

The photostimulated reactions of ButHgCl with 1,1-diarylethylenes yield different products for the aryl groups C6H5, p-O2NC6H4, or p-MeOC6H4 reflecting the donor or acceptor properties of ButCB2Ċ(Ar)2.