Isothiocyanato complexes

An interesting study with BATO compounds concerns the linkage isomerization of coordinated [NCS] in [Tc(NCS)(cdoh)2(cdo)(BMe)] (440). Both a red, N-bond isothiocyanato complex [Tc(NCS)(cdoh)2(cdo)(BMe)] and the brown, S-bond thiocyanato complex [Tc(SCN)(dmg)3(BR)] (441) were isolated from the direct synthesis from [Tc04] . The N-bound (440) was found to be thermodynamically more stable than the S-bound isomer (441) and the conversion was monitored elegantly by spectroscopic methods. The X-ray crystal structure of (440) was determined. The NCS and SCN -substituted analogues exhibited r c N stretch at 2,114-2,124 cm and at 2,055-2,079 cm , respectively. " (Scheme 59). 

Certain palladium complexes of the type PdL(N3) react with carbon disulfide apparently to give thiatriazolinato complexes. However, they are unstable and decompose at temperatures above 40 °C to produce the corresponding isothiocyanato complexes, PdL(NCS) <90ICA27>. 

Isothiocyanato complexes, osmium, 37 293 Isothiocyanatocyclophosphazene, mass spectra, 21 94 Isotopes... 

IR spectra of isocyanato and isothiocyanato complexes of nickel(II) have been widely studied 108°-1082>1086>108 ... 

Furthermore, isothiocyanate complexes can be prepared starting from the metal-azido complexes and reacting these with CS2. These reactions most probably proceed via 1,3-dipolar cycloaddition reactions.354 Syntheses of isothiocyanato complexes via this route are known for several metals (see, for example, ref. 355 for a synthesis involving Co). In these reactions formation of a cyclic intermediate (cf. equation 24) could be established. 

The reductive decomposition of thiocyanato complexes should be applicable to the electrodeposition of other metal sulfides. We have tried this with Pd2, Co2+, Ni2+, Zn2+ and In3+.I8 While thin films of PdS, CoS and NiS could be successfully electrodeposited, other metal sulfides such as ZnS and In2S3 could not be obtained. This is an interesting series of results when we think of the softness (hardness) of these metals as acid. TC coordinates with its sof basic S atom to soft acidic Cd2+ and Pd2+, while hard acidic In3+ only permits coordination with hard basic N atom to form an isothiocyanato-complex. Other metals are at the borderline accepting coordination of both S and N. Because reduction of TC is catalyzed by a central metal,75,76) such ligand reduction may result in the formation of metal sulfides only for thiocyanato-complexes. The difference in bahavior among Co2+, Ni2+ and Zn2+ could be reasoned as the consequence of efficient catalysis of the electron transfer reaction by the transition metals. Such trends fit nicely with the previous findings by electrochemical analyses. 7) It is therefore understood that the chemical structure of the active species is decisive to the film formation. Thus, designing such molecular precursors which are chemically stable but can be electrochemically decomposed to metal sulfides should broaden the possibilities of electrochemical thin film synthesis. 

In isothiocyanato-complexes of the type [Co(en) 2(NCS)X]n+ exchange of coordinated isothiocyanate is slow, and Werner (127) had shown that several oxidants caused the reaction (4)... 

The five-coordinate zirconocene dichloride 1178 contains a tethered bis(Cp)-phosphine ligand it was prepared by salt metathesis of ZrCl4(THF)2 with Li2[PhP(CFI2CF[2C5F[4)2].911 Coordination of the phosphorus atom to the metal center was confirmed by its X-ray structure. Dissolution of 1178 in wet MeOH followed by evaporation of the solvent yielded the cationic chloro-aqua complex 1179 shown in Scheme 277 as the chloride salt. Treatment of an aqueous solution of 1178 with excess potassium thiocyanate gives the bis(isothiocyanato) complex 1180. 

The neutral nitrido-isothiocyanato complex [ rcN(NCS)2(CH3CN)(PPh3)2] 0.5CH3( N was synthesized by substitution of the ehloride atoms in [TcNCl2(PPh3)2] with NCS in water/ethanol followed by the reaetion of [TcN(NCS)2(PPli3)2]° with... 

Halogeno and isothiocyanato complexes with phosphine, phosphonite or arsine ligands... 

A structurally analogous compound is the isothiocyanato complex trans-[Tc"(NCS)2(dppe)2] which was synthesized by the action of excess LiSCN on [Tc X2(dppe)2] (X = Cl,Br) in DMF or ethanol at 80-100 (397]. The rose-colored... 

M—NC, isocyano complex M—NCO, isocyanato complex M—NCS, isothiocyanato complex M — NCSe, isoselenocyanato, complex... 

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