Wurtz-type reductive coupling reaction of primary alkyl iodides and haloorganotins in cosolvent/H2O(NH4Cl)/Zn media as a route to mixed alkylstannanes and hexaalkyldistannanes

Mixed tetra-alkylstannanes R3SnR′ (R=Et, n-Pr, n-Bu and R′=Me, Et, n-Pr, n-Bu, n-Pent) and R2SnR′2 (R=n-Bu and R′=Me, Et, n-Pr, n-Bu) can be easily prepared in a one-pot synthesis via coupling reaction of alkyl iodides R′I with R3SnX (X=Cl, I) and R2SnCl2 compounds in cosolvent–H2O(NH4Cl) medium mediated by zinc dust. Coupling also occurs with (Bu3Sn)2O. It has been verified that reactions are possible only with primary alkyl iodides; with secondary alkyl iodides the coupling reaction fails. When alkyl chlorides and bromides are used ditin compounds are obtained instead of the unsymmetrical tetra-alkylstannanes. This represents a route to hexaalkyldistannanes.