Thio derivative ligands

The synthetic route to the oxo-thio mixed-ligand halo germanates lOla-d is similar to the synthesis for related oxo derivatives In the first stage the tetracoor-... 

Octahedral complexes of the form ML2X2 (M = Co" or Ni") are known with /ru -(2-ethyl-thio)cyclopentylamme," with 2-(methylthiomethylpyridine (31 R = Me)" and with 2-methyl-8-mercaptoquinoline (29 R = Me, R = H)." With the latter sterically hindered ligand only the thiocyanate complexes are octahedral, the halide complexes being tetrahedral. Complexes of this ligand with Cu" and Cu also were investigated. A number of complexes of 1-thiocarbamylpyrazole (32), and substituted forms, are known. These were discussed by Trofimenko in a review of pyrazole-derived ligands." ... 

The UV-cataiyzed reaction of Mc2PH with the vinyl-Ts silasesquioxane yields quantitatively the novel octakis(dimethylphosphinoethyl)octasilasesquioxane as the first reactive siloxane-based molecule with polydental o-donor properties emphasized by the easily performed conversion into the thio derivative or the formation of an octatungsten complex with W(CO)5-THF. Future work, therefore, has to focus on both the introduction of other phosphane ligands PR2 into the Si-O cage and the reaction with suitable transition metal fragments. 

Scheme 3.10 L-Valine-derived P-amino thio ligands for addition of ZnEt2 to benzaldehyde.

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