[en] A microscale technique has been developed for the preparation of /sup 117m/SnCl₄. The radiolabeled tin tetrachloride is an important intermediate for the synthesis of /sup 117m/Sn-labeled organic radiopharmaceuticals. The flow-through system involves high temperature chlorination of metallic /sup 117m/Sn with subsequent cryogenic collection of the /sup 117m/SnCl₄ in a special reaction vessel. This vessel can then be used for the conversion of the tin tetrachloride to various useful intermediates. The reactions that have been studied include the formation of tetraalkyl and tetraaryltin compounds by reaction of SnCl₄ with Grignard or alkyl and aryl lithium reagents (SnCl₄ → R₄Sn or Ar₄Sn). In addition, by stoichiometric control, the comproportionation of SnCl₄ with tetramethyltin can yield any one of the mixed methylchlorotin intermediates, MeSnCl₃, Me₂SnCl₂, or Me₃SnCl. These products are important intermediates for the preparation of /sup 117m/Sn-labeled steroids, fatty acids, amino acids, barbituates, and a variety of other potentially useful agents