Ruthenium carbon disulfide

Itoh and co-workers reported the ruthenium(n)-catalyzed [2 + 2 + 2]-cycloaddition of 1,6-diynes with isocyanates to afford the corresponding bicyclic pyridones 163 (Scheme 72).356 357 For previously reported ruthenium-catalyzed [2 + 2 + 2]-cycloaddition of 1,6-diynes see Refs 358 and 358a, and for theoretical calculations of the cyclocotrimer-ization of alkynes with isocyanates, isothiocyanates, and carbon disulfide see Refs 359 and 359a. 

For a related example of a ruthenium(II)-catalyzed cycloaddition of 1,6-diynes with isothiocyanates and carbon disulfide, see Yamamoto, Y. Takagishi, H. Itoh, K. J. Am. Chem. Soc. 2002, 124, 28-29. 

A theoretical study of the mechanism of ruthenium-catalyzed formation of pyran-2-one and the corresponding sulfur and selenium analogues 8 from acetylene and CX2 (X = O, S, Se) has been reported (Equation 3) <2004NJC153>. This cyclotrimerization reaction has been experimentally carried out using carbon disulfide as a substrate <2002JA28>. The proposed mechanism involves formation of a bicyclic metal carbene intermediate. Formation of this intermediate seems to be particularly unfavorable energetically in the case of carbon diselenide. 

The ruthenium complex Cp RuCl(COD) catalyzed the [2+2+2] cycloaddition of 1,6-diynes with heterocumulenes such as isocyanates, isothiocyanates, or carbon disulfide [99,100]. Bicyclic pyridones [99] and bicyclic thiopyrans [100] were thus obtained (Eq. 76). 

One of the most important links between alkylidyne and alkyne compounds is that one of the first synthetic routes for cobalt al-kylidynes involved alkynes as reagents (264-268). In later studies, several other synthetic routes to cobalt (269-280), rhodium (281, 282), iron (283-285), molybdenum (286, 287), ruthenium (288-292), osmium (293, 294), nickel (295, 296), and some mixed-metal (165, 297-302) clusters have been developed. Reagents employed include carbynes (166, 277, 280), alkali metals (269), carbon disulfide (275), dithioesters (276, 282), RCC13, and acids (281, 282). 

The reaction of dithiocarbonate complexes of ruthenium 52 with carbon disulfide affords trithiocarbonate complexes 53. The reaction proceeds via addition across the ruthenium-sulfur bond with generation of 54 and carbonyl sulfide4. ... 

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 . ... 

Addition of disulfides to carbon-carbon double bonds is catalyzed by ruthenium complexes (Equation (71)).204 Even relatively less reactive dialkyl disulfides add to norbornene with high stereoselectivity in the presence of a catalytic amount of Cp RuCl(cod). Diphenyl disulfide adds to ethylene and terminal alkenes under identical conditions (Equation (72)). 

Phenyl ethylenesulfonate, 241 Tin(IV) chloride, 300 Containing one sulfur 2,4-Bis(4-me thoxyphenyl)-1,3-dithia-2,4-diphosphetane-2,4-disulfide, 38 Titanium(IV) chloride-Zinc, 310 Other five-membered heterocycles Carbon dioxide, 65 Methanesulfonyl chloride, 176 Six-membered rings Containing one nitrogen—piperidines Dichlorotris(triphenylphosphine)-ruthenium(II), 107 Mercury(II) trifluoroacetate, 175 Tetrakis(triphenylphosphine)-palladium(O), 289... 

Chemically modified electrodes have also been employed as detectors for CEEC [33,34]. Specifically, carbon paste modified with cobalt phthalocyanine was explored in our laboratories for selective detection of thiols [33]. Electrodes were produced by packing a 150 pm i.d. fused silica capillary with modified carbon paste to a depth of approximately 5 mm. This electrode was used for the selective detection of cysteine in urine. Later, ruthenium cyanide-modified electrodes were used for the simultaneous detection of thiols and disulfides at +850 mV (vs. Ag/AgCl) [34]. Modified carbon fiber microelectrodes were prepared by cycling the potential between 500 and 1000 mV at a scan rate of 50 cycles in an acidic deoxygenated plating solution containing RuClj, K RuiCN), and KCl. Detection limits for cystine were 3 pM. The selective detection of cystine in urine of a patient with kidney stones was demonstrated. 

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