Thermolysis of Bis(arylmethyl)tin Dichlorides: An Efficient Reagent For C-C Bond-Forming Reactions

DOI: https://doi.org/10.54985/peeref.2401w1967604

Dr. Thirumoorthi Ramalingam · Jan 23, 2024

The oxidative-addition reaction between an arylmethyl chloride (RCH2Cl; R=1-C10H7, 2,4,6-Me3C6H2, 4- MeC6H4, 3-MeC6H4, C6H5, 4-ClC6H4) and tin powder in boiling toluene produces bis(arylmethyl)tin dichlorides, [(RCH2)2SnCl2] in good yields. Bis(1-naphthylmethyl)tin dichloride undergoes Sn-C homolytic cleavage at 160°C in mesitylene to produce two 1-naphthylmethyl radicals (1-C10H7CH2•), which were trapped by TEMPO (C9H8NO•). Subsequently, the radicals (RCH2•) generated in this manner were utilized for efficient substitution reactions with electron-rich arenes (R1H; R1= 2,4,6-Me3C6H2, 1,2,4,5-Me4C6H, 1,2,3,4,5-Me5C6) to obtain a variety of unsymmetrical diarylmethanes. (RR1CH2). The addition of one equivalent of iodine (I2) to the reaction mixture resulted in a significant increase in the yields of coupled products.