Thiazoles metal complexes

MS has also been widely used to characterize thiazole-containing odors <2006EOC465>, flavors <2006EET675>, thiazole-metal complexes <2005ICA(358)2781>, natural products <2004JPS2953>, and protein-thiazole complexes <2004JME6658>. 

All the early literature concerning thiazoles mentions numerous metallic complex-salts formed by addition to the thiazole of the aqueous solution of the metal salt and that could be used for identification purposes. The most usual complexes so obtained are platinum double salts, for example, (4-methylthiazole HC1)2 PtCU (m.p. deep 204°C) (25), or mercuric chloride derivatives, for example, 2,4-dimethyl-thiazole 2 HgCl (m.p. deep 176-177°C) (458). 

Aza-aromatic compounds can give rise to metallic complexes, and various complexes of thiazole have been studied ... 

Thiazole, 4-methyl-5-(2-hydroxyethyl)-in thiamine biosynthesis, 1, 97 Thiazole, 4-methyl-2-methylami nosynthesis, 6, 300 Thiazole, 4-methyl-2-phenyl-alkylation, 6, 256 mercuration, 6, 256 Thiazole, 2-(methylthio)-methylation, 6, 290 thermodynamic values, 6, 291 Thiazole, 2-methylthio-5-phenyl-synthesis, 5, 153 Thiazole, 4-methyl-5-vinyl-occurrence, 6, 327 Thiazole, 2-phenyl-acetylation, 6, 270-271 Conformation, 6, 237 synthesis, 5, 113, 6, 306 Thiazole, 4-phenyl-conformation, 6, 237 2,5-disubstituted synthesis, 6, 304 Thiazole, 5-phenyl-conformation, 6, 237 Thiazole, 2-phenyl-5-triphenylmethyl-synthesis, 6, 265 Thiazole, 2-(2-pyridyl)-metal complexes, 5, 51 6, 253 Thiazole, 4-(2-pyridyl)-metal complexes, S, 51 6, 253 Thiazole, tetrahydro-ring cleavage, 5, 80 Thiazole, 2,4,5-trimethyl-occurrence, 6, 327... 

Most of the substrates that give both types of cycloaurated complexes are limited to pyridine derivatives, although recently a few exceptions have been reported with thiazoles and imidazoles. The reaction of substituted pyridine ligands such as phpy,1 49,1924 2-benzoyl pyridine,1924 2-anili-nopyridine,1925,1926 l-(2-pyridylamino and 2-pyrimidinylamino)naphthalene, 7 2-phenoxypyri-dine,1811 2-(phenylsulfanyl)pyridine,1925 2-(2-thienyl)pyridine, 8 2-(3-thienyl)pyridine,1928 2-(alkylsulfanyl)pyridine,1929 or papavorine1930 at room temperature yields the nonmetallated compounds which, upon heating, are transformed into the metallated complexes [Au(N,C)Cl2], The process with phpy is illustrated in Scheme 21. 

The first examples for the oxidative addition of 2-chloro thiazoles to complexes of cf or metal centers were reported by Roper et al. more than 30 years ago [107, 108]. In 2001 Cavell and Yates showed by detailed experimental studies supported by DFT calculations that the oxidative addition of the C2-X bond of imidazolium... 

Like pyridines, thiazoles form complex salts by addition to aqueous solutions of metal salts and these complexes have long been used for the identification of the heterocycle. The most common complexes utilized are platinum double salts such as, for example, (4-methylthiazole-HCl PtCL (m.p. dec. 204 °C). 

Lappert developed the thermolysis of an electron-rich olefin in the presence of a transition metal complex as another way to synthesise these compounds [4], When, in 1975, Clarke and Taube published their findings on carbon coordinated purine transition metal complexes [5], transition metal NHC complexes with functionalised NHC made their debut in biochemistry. The chemistry of carbenes from natural products became firmly established following the discovery that the catalytic activity of thiamine (vitamin Bl) is based on the intermediate formation of a carbene derived from thiazole [6-9] (see Figure 1.2). 

Novel Thiazole Catalysts and Transition Metal Complexes... 

Mercuration, of alkylthiazoles, 380 as extractive technique, 380 Metallic complex, of thiazoles, 392 w Method, 27 ur" Method, 27... 

Moreover, aryl-oxazoles, -imidazoles [17], or-thiazoles [18], anhydrides [19], and imides [20] are accessible via intramolecular Heck-type carbonylations. In addition to typical acid derivatives, aldehydes [21], ketones [22], aroyl cyanides, aroyl acetylenes, and their derivatives [23] could be synthesized via nucleophilic attack of the acyl metal complex with the corresponding hydrogen or carbon nucleophiles. Even anionic metal complexes like [Co(CO)4] can act as nucleophiles and lead to aroylcobalt complexes as products [24]. 

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