We report the syntheses and structures of homoleptic diphenylphosphinothioicamido potassium and barium complexes of the molecular formula [{K(THF)2Ph2P(S)N(CHPh2)}2] (2)] and [Ba(THF)2{Ph2P(S)N(CHPh2)}2] (3)], respectively. The potassium complex 2 can be obtained in good yield by the treatment of diphenylphosphinothioicamine [Ph2P(S)NH(CHPh2)] (1) and potassium bis(trimethylsilyl)amide in tetrahydrofuran (THF). However, the barium complex 3 was prepared by two synthetic routes; first by the silylamide route where the barium bis-trimethylsilyl amide [Ba{N(SiMe3)2}2(THF)2] was treated with 1 in 1:2 molar ratio in THF to afford 95% of the product via the elimination of hexamethyldisilylamine. In the second method, potassium complex 2 was treated with barium diiodide in THF to yield the same product 3 in 85% yields. In the solid state, the potassium complex 2 is dimeric and form highly strained polymetallacyclic motif through the coordination of nitrogen, phosphorus, and sulfur atoms of the diphenylphosphinothioicamido moieties. The solid state structures of 2 and 3 were established by single-crystal X-ray diffraction analysis. In the molecular structure of barium complex 3, the barium adopts a pseudo-octahedral geometry and a direct barium sulfur bond is observed. © 2014 Taylor and Francis Group, LLC.