6- -pyridine-2-thiolate

Pyrido[2,l-4][l,3,5]thiadiazine derivatives 175 were prepared from pyridine precursor treatment of iV-iucthylruor-pholinium salt of pyridine thiolates 174 with primary amines and formaldehyde afforded compounds 175 (Equation 27) <2003DOC92>. 

The higher reactivity of 2-halogenothiazoles with respect to halogenopyridines can be related to the different aromaticity of the two systems, less for thiazole than for pyridine, for example, the relatively stronger fixation of the tt bond in the thiazole than in the case of pyridine. As the data reported in Table V-1 (footnote a) indicates, the free thiophenol is more reactive than the thiolate anion toward the 2-halogenothiazoles. This fact should be considered when one prepares the thiazolyl sulfides. 

The most thoroughly studied mixed S jA-ligand is pyridine-2-thiolate because of its versatile coordination modes. The compound [Ag(SPy)] has a graphite-like array of silver(I) ions and has a semiconductor behavior. The PyS ligand acts as a fi3-N,S,S bridge. [Ag5(SPy)(HSPy)BF4] has a layered structure with the coordination modes of PyS showed in Figure 14.1 04... 

Figure 14 Coordination modes of pyridine-2-thiolate in [Ag5(Spy)(HSpy)BF4]n.

Methyl- l-[methyl-(2-pyridin-2-yl-ethyl)amino]propane-2-thiol (108) is a tridentate N2S ligand with an aliphatic thiolate ligand. The single-crystal X-ray structures demonstrate that the zinc complexes are close structural analogs of the His2Cys site found in peptide deformylase.873... 

Williams and Rastetter also accomplished an elegant synthesis of ( )-hyalodendrin (83) in 1980 [39]. Beginning with the sarcosine anhydride-derived enolic aldehyde 78, silyl protection of the enal enabled alkylation of the glycine center with benzyl bromide and thiolation using LDA and monoclinic sulfur a la Schmidt. After protection of the thiol with methylsulfenyl chloride and deprotection of the silyl ether, the enol was sulfenylated with triphenylmethyl chlorodisulfide to afford bis(disulfide) 82 as a 2 1 mixture of diastereomers favoring the anti isomer. Reduction of the disulfides with sodium borohydride and oxidation with KI3 in pyridine afforded ( )-hyalodendrin (83) in 29 % yield (Scheme 9.4). 

Thiols like pyridine-2-thiol yield (carbene)gold thiolates, and onium salts give cationic (carbene)gold ylide complexes, isolated and characterized as the perchlorates.170 The reaction of dithiocatechol with (cyclohexylisocya-nide)gold chloride affords a carbene complex [(CyNC)AuC(NHCy)2]+Cl-, which co-crystallizes with a neutral tetranuclear complex [(CyNCAu)2Au2(S2C6H4)2].224... 

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