Repetition of a published procedure for the preparation of several N-substituted l-amino-2- methylpropane-2-thiols (2a-d) for use as bidentate ligands indicated that the products characterized therein were not thiols, but the corresponding disulfides (3a-d). Preparation of the authentic thiols was accomplished by reduction of the intermediate Schiff's bases (la-d) with LiAlH4 in refluxing tetrahydrofuran. The novel tetradentate 5 was also synthesized ...