Temperature-Assisted Generation of Arylmethyl Radicals from Bis(arylmethyl)tin Dichlorides: Efficient Reagents for - Bond-Forming Reactions.

The oxidative-addition reaction between an arylmethyl chloride (RCH Cl; R=1-C H , 2,4,6-Me C H , 4-MeC H , 3-MeC H , C H , 4-ClC H ) and tin powder in boiling toluene produces bis(arylmethyl)tin dichlorides, [(RCH ) SnCl ] in good yields. At 160 °C in mesitylene bis(1-naphthylmethyl)tin dichloride undergoes Sn-C homolytic cleavage to generate two 1-naphthylmethyl radicals (1-C H CH ⋅) which were trapped by TEMPO (C H NO⋅). Subsequently, the radicals (RCH ⋅) produced in this manner were utilized for efficient substitution reactions with electron-rich arenes (R'H; R'=2,4,6-Me C H , 1,2,4,5-Me C H, 1,2,3,4,5-Me C ) to obtain a variety of unsymmetrical diarylmethanes (RR'CH ).

1-Hy-droxy-4-methyl-pyridinium chloride.

The title salt, CHNO·Cl, contains two cations and two anions in the asymmetric unit. The components are linked by O-H⋯Cl and C-H⋯Cl hydrogen bonds, leading to tetra- (square-planar) or penta-coordinated (square-pyramidal) chloride ions. The title salt is isostructural with its bromide analogue.