AbstractA study was made of the transfer of isobutyl groups from aluminium to tin, which appears to be reversible. An equilibrium is reached in each case, the position of which is determined by the total number of isobutyl groups present and the ratio Al/Sn. The results are presented in one single graph.Special attention was given to the alkylation of stannic chloride with tri‐isobutylaluminium and the influence of alkali chlorides on this reaction. Addition of alkali chlorides in various amounts leads to a more complete transfer of isobutyl groups to the tin ato