Selenium donors

Complexes of Mercury(l) with Sulfur- and Selenium-Donor Ligands. 

There have been no reports of complexes of " JV-substituted thiosemicarbazones derived from 2-formylpyridine, but 2-acetylpyridine JV-methyl-thiosemicarbazone, 3a, formed [Fe(3a-H)2]C104 and [Fe(3a-H)2]FeCl4 [117]. The nature of these two species was established by partial elemental analyses, molar conductivities, magnetic moments, electronic, infrared, mass and electron spin resonance spectra. A crystal structure of a related selenosemicarbazone complex confirmed the presence of a distorted octahedral iron(III) cation coordinated by two deprotonated anions so that each ligand is essentially planar and the azomethine nitrogens are trans to each other the pyridyl nitrogen and selenium donors are both cis. 

Platinum(II) Complexes with Sulfur- and Selenium-donor Ligands 715... 

The hydrolysis, alcoholysis, and aminolysis of monoselenophosphate (294) have been reported for the first time (294) is the labile selenium donor compound required for the synthesis of Se-dependent enzymes and seleno-tRNAs, and is formed from ATP and selenide, HSe. The rate of hydrolysis of monoselenophosphate (294) is... 

Sulphur and selenium donor ligands. The reaction between AgNOj and the series of thiocarbazide derivatives RCONHNHC(S)NHNH2 (R == Me, Ph, or C6H4N) has produced white diamagnetic solids for which the polymeric structures (94) are proposed. Support for these structures comes from their low solubility, and i.r. data suggesting terdentate co-ordination via the terminal N, the amido N, and the S atom. The Ag ion attains its usual co-ordination... 

This magnesium-dependent enzyme [EC 2.7.9.3], also known as selenide,water dikinase and selenium donor protein, catalyzes the reaction of ATP with selenide and water to produce AMP, selenophosphate, and orthophosphate. 

These methods are limited in scope. Direct thiation has been reported for the transformation of vicinal diketones to [3,4]-annelated thiophenes <1996CHEC-II(7)49>. Thionations and selenations of vicinal halomethyl ketones with thioacetamide or iV,iV-diethylselenopropionamide as sulfur and selenium donors, respectively, have also been reported <1996CHEC-II(7)49>. In a recent example, thieno[3,4-f]pyrazoles 160 were readily prepared from aryl 5-bromomethyl-l//-l-phenylpyrazole-4-yl ketones 159 by reaction with thioacetamide (Equation 35) <1998JHC71>. Additionally, an example of an amination cyclization by reaction of 161 with benzylamine to afford pyrrolo[3,4-i/ thiazole 162 has been described (Equation 36) <1998JHC71>. 

Complexes of group VIB elements with sulfur or selenium donor atoms are mainly concerned with complexes of selenium(II), tellurium(II) and tellurium(IV). The structural chemistry of complexes of selenium and tellurium with sulfur- and selenium-containing ligands has been well reviewed in the recent past.11... 

Complexes with sulfur and selenium donor ligands 1350... 

COMPLEXES OF GOLD(I) WITH SULFUR AND SELENIUM DONOR LIGANDS 872... 

The number and variety of coordination complexes of palladium(II) with sulfur-containing bidentate or multidentate ligands is legion, and it is possible here only to summarize the different kinds of complexes formed and to guide the reader into the literature. Table 2 contains a selection of typical palladium(II) complexes of bi- or multi-dentate sulfur or selenium donor ligands, and comments on pertinent aspects of particular complexes. Chelate... 

Table 2 Some Typical Palladium(II) Complexes of Bi- or Multi-dentate Sulfur or Selenium Donor Ligands...

Complexes of bidentate and multidentate selenium donor ligands... 

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