AbstractBis(tri‐n‐butyl)tin‐113 oxide was prepared from tetrabutyltin and tin‐113 tetrachloride by redistribution reaction between alkyl groups, with the formation of the intermediate tri‐n‐butyltin‐113 chloride, which was hydrolyzed to form the desired product. Purification of the reaction mixture by alumina column chromatography, followed by thin layer chromatography, revealed a pure sample. The sample was also distilled under vacuum as a further check on the efficiency of the purification methodology; radioactivity resided in the bis(tri‐n‐butyl)tin oxide fraction. Infra‐red analysis of similarly prepared non‐radioactive sample showed the SnOSn bond; the spectra agreed with published spectra, and with the spectra obtained in our laborator