Mechanisms of the reactions of chloromethanes with trimethylstannylsodium. Synthesis of tetrakis[trimethylstannyl]methane.

The reactions of CCl₄, CHCl₃, and CH₂Cl₂ with trimethylstannylsodium in tetraglyme have been examined. Tetrakistrimethylst?annyl]methane can be obtained by reaction with CCl₄ in yields of about 40%. Among other products which have been characterized in varying degree are the following: trichloromethyltrimethylstannane, bistrimethylstannyl]dichloromethane, tristrimethylstannyl]methane, and hexamethyldistannane, The first step in the reaction leads to the formation of the trichloromethyl anion, and dichlorocarbene has been trapped with 2,3- dimethyl-2-butene. Dichlorobistrimethylstannyl]methane reacts with Me₃SnNa to form tetrakistrimethylstannyl]methane in 85% yield. When the reaction was carried out in the presence of $\text{t}$-butyl alcohol the only product formed was bistrimethylstannyl]methane, indicating carbanionic intermediates. Chloroform yields tetrakistrimethylstannyl]methane and bistrimethylstannyl]methane, but no detectable tristrimethylstannylmethane. Trapping experiemtns with 3-pentanol and 2,3-dimethyl-2-butene indicate the intermediacy of dichloromethyl anion and of dichlorocarbene. Methylene chloride yields bistrimethylstannyl]methane. No intermediates could be trapped by added alcohol.