Azaheterocycles metal

The external y-metalation of nonfused azaheterocycles has received considerable attention in aromatic lithiation chemistry, although often... 

Metalation of 6-membered azaheterocycles is similar to that of their five-membered counterparts, and thus the rm-butylformamidine derivative of... 

Because of lower steric constraints, or/Ao-metalation generally occurs more readily with six-membered ring-fused azaheterocycles than with five-membered species, and thus the directed /3-metalation of 1,2,3,4-tetrahydroquinoline has been achieved in combination with a r-BOC protecting group (Scheme 148) (89TL1197). 

Seven-membered azaheterocycles such as azepines have received much less attention than their five- or six-membered counterparts, although, as with the related 2,3-pyrroline and 1,2,3,4-tetrahydropyridine compounds, the tm-butylformamidine derivative of azepine has been a-metalated with... 

Like the related organolithium-pyridine adducts (see Section II,D,2,d), the dihydropyridyl metal adducts considered in this Section are found to be good hydride donors toward a number of carbonyl and other compounds.152 Hydride transfer from such adducts has also been shown to occur toward a variety of azaheterocyclic substrates, thus generating, in turn, the corresponding adducts. Such a transfer has been carried out with pyridine, (V.AT-dimethylnicotinamide, quinoline, isoquinoline, 2,2 -bipyridyl and its isomers, and 1,10-phenanthroIine.158... 

Cross coupling , Acc. Chem. Res. 2008, 41, Special issue (11), 1439-1564 Metal-Catalyzed Cross-Coupling Reactions , 2nd Edn, de Meijere, A. and Diederich, F, Eds., Wiley-VCH, Weinheim, 2004 Catalytic cross-coupling reactions in biaryl synthesis , Stanforth, S. R, Tetrahedron, 1998, 54, 263 Organometallics in coupling reactions in 7t-deficient azaheterocycles , Undheim, K. and Benneche, T.,Adv. Heterocycl Chem., 1995, 62, 305. 

Due to the presence of the carboxyl and fi-oxo groups, as well as azaheterocyclic fragments, fluoroquinolones have a profound ability to form metal-chelates, and other ionic structures. It is known that complexes with metals may enhance activity of fluoroquinolones due to a better solubility and endocellular accumulation [357, 358]. The crystal structures of a number of metal complexes, results of their thermal analysis, IR and NMR spectra of complexes and their bioactivity have been considered [359]. In the recently published review article [360] the data concerning the structure and properties of metal complexes of fluoroquinolones, and their interaction... 

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