The Alkali Metal Salts of Methyl Xanthic Acid

Methyl xanthates of the type M(SSC‐OMe) (M = Li–Cs) are readily formed when carbon disulfide is reacted with the corresponding alkali metal hydroxides in methanol exposed to air, or with the alkali metal methoxides in dry methanol or THF under exclusion of air. The reactions are easily monitored by 13C NMR spectroscopy. The Na, K, Rb, and Cs salt could be isolated in high yields, while the Li salt decomposed upon attempted isolation. All compounds are readily complexed by crown ethers and form isolable 1:1 adducts, including the elusive Li salt. All products were studied by NMR (1H, 13C, and alkali metal nuclei) and IR spectroscopy, and most of them where structurally characterized by single‐crystal X‐ray diffraction. Li(SSC‐OMe)(12c4) (12c4 = [12]crown‐4) and Cs(SSC‐OMe)(18c6) (18c6 = [18]crown‐6) represent the first structurally characterized lithium and caesium xanthate complexes, respectively. The preparation, properties, and molecular structures of Methyl xanthathes of the type M(SSC‐OMe) (M = Li–Cs) as well as their crown ether complexes are reported. Li(SSC‐OMe)(12c4) (12c4 = [12]crown‐4) and Cs(SSC‐OMe)(18c6) (18c6 = [18]crown‐6) represent the first structurally characterized lithium and caesium xanthate complexes, respectively.