Insertion of carbon disulfide

The free dithiocarboxylic acids can be isolated, but their salts are preferred. In some cases their metal complexes can be prepared directly by insertion of carbon disulfide into metal-carbon bonds. Thus, the reaction of Grignard reagents, RMgX, with CS2, followed by acid treatment gives the dithiocarboxylic acids RCSSH and metal complexes in good yields.311... 

Note also the reactivity of the heteroleptic plumbylene 174 toward carbon disulfide. Treatment of 174 with excess amount of carbon disulfide resulted in a formation of unexpected product, lead(II) bis(aryl trithiocarbonate) (192), as a yellow, air- and moisture-stable solid (Scheme 14.85). The reaction must involve not only the insertion of carbon disulfide into the Pb—S bond, but also the formal insertion of a sulfur atom into the Pb C(Tbt) bond and subsequent insertion of another... 

The only known complex with a fluorodithioformato ligand, compound (90), can be prepared by insertion of carbon disulfide into the Pt—F bond of (91).100... 

An interesting plumbylene stabilized by intramolecular Pb- S interactions is obtained by the double insertion of carbon disulfide into Pb S bonds of bis(arylthio) plumbylene according to equation (12). 

Abstract In this chapter, we review dithiocarboxylic acid salts. Methods of synthesizing these salts are reviewed, such as insertion of carbon disulfide into the metal-carbon bond, reaction of a dithiocarboxylic acid with a transition metal salt in the presence or absence of a base, ligand exchange of dithiocarboxylato metal or ammonium salts with another metal complex bearing a leaving group, and so on. The dithiocarboxylic acid complexes exhibit a variety of coordination styles that have been characterized by X-ray crystallographic analysis. Spectroscopic (IR, C, and UV-Vis) properties of the salts are summarized. The reactivities, structures, properties, characteristics and applications of each salt are discussed in detail for the salts of most elements (except for carbon). 

Many transition metal complexes bearing dithiocarboxylato ligands have been studied from various points of view. Their coordination modes depend on the metals and the other ligands on the metals. The complexes sometimes show interesting properties, such as electron conductivity. Synthetic methods are usually as same as those of the main-group-element complexes bearing dithiocarboxylato ligands. The insertion of carbon disulfide into the metal-carbon bond is especially used in the synthesis of transition metal complexes. 

The insertion of carbon disulfide into P-N single bonds was already observed by Michaelis and Kaene in 1898, who obtained a 2 1 adduct 99 from carbon disulfide and phenyldip-iperidinophosphorane 98. The structure 99 of the adduct was elucidated by Vetter and Noth in 1963. ... 

Insertion of carbon disulfide into Mn-0 and Re-O complexes of (CO)3(P-P)MOR (where P-P is l,2-bis(diphenylphosphinoethane) also occurs readily . ... 

Double insertion of carbon disulfide into lead(ii)bisarenethiolates 111 to give 112 is also observed . 

Insertion of carbon disulfide into platinum metal-hydrogen bonds is known , and insertion of carbon disulfide into alkoxo-palladium bonds also occurs . Insertion of carbon disulfide into ruthenium alkenyl bonds gives rise to the formation of an alkenedithiocar-boxylate ligand . ... 

Examples of the insertion of carbon disulfide into carbon-nitrogen bonds is also known. Dipiperidinomethane 113 reacts with carbon disulfide to give the insertion product 114 . ... 

Insertion of carbon disulfide into M-H, M-C and M-S bonds is a well-known process (see GOMG (1995)). In accord, thiolato complex [Ru(SGH2GH=GH2)Gp(PPh3)2] readily reacts with GS2 to give the thioxanthate complex... 

Copper complexes of bis(2,2 -dipyridyl)dithiocarbamate have been prepared upon insertion of carbon disulfide into the copper-nitrogen bonds of the corresponding 2,2 -dipyridylamine (dpa) complexes (195, 196). Kumar and Tuck (195) initially noted this behavior for [Cu(dpa)] , [Cu(dpa)2], and [Cu(dpa)(dppe)l [dppe = l,2-bis(diphenylphosphino)ethane], but characterization was made only on the basis of the presence of characteristic v(C—S) and v(C—N) bands in their IR spectra. Later, this was confirmed by the X-ray crystal structure of [Cu(S2Cdpa)2], formed upon slow evaporation of a carbon disulfide solution of [Cu(dpa)2] (Eq. 21) (196). The transformation is actually quite complex as in the dpa complex, metal coordination is through the nitrogen atoms of the pyridyl rings (197), and thus a rearrangement to the amide form must occur prior to carbon disulfide insertion. 

Similarly, insertion of carbon disulfide into the nickel-nitrogen bonds of [Ni S(CH2)3NH2 2] results in proton transfer from nitrogen to sulfur, being proposed to afford [Ni S2CNH(CH2)3SH 2] (Eq. 23) (199). 

The development of niobium and tantalum dithiocarbamate chemistry is relatively recent, the first well authenticated examples coming from the insertion of carbon disulfide into metal amide complexes to give [M(S2CNR2)4] (193, 666). Dithiocarbamates are now known to stabilize niobium and tantalum in the +3 to +5 oxidation states. 

A number of other synthetic routes have also been developed toward copper bis(dithiocarbamate) complexes. Two groups have prepared the bis(2,2 -dipyr-idyl)dithiocarbamate complex 447 (Fig. 221) upon insertion of carbon disulfide... 

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