2,2 -Bipyridyl synthesis

The Boekelheide reaction has been applied to the synthesis of non-natural products with the preparation of quaterpyridines serving as an example. The sequence began with the 2,4-linked bipyridyl-N-oxide 25. Execution under the typical reaction conditions produced the expected bis-pyridone 26. Treatment with POCI3 afforded the corresponding dichloride that was submitted to a palladium-catalyzed coupling with 2-stannyl pyridine to produce the desired quaterpyridine 27. 

Chromium, tetraaquadichloro-chloride dihydrate hydrate isomerism, 1, 183 Chromium, tetrabromo-solvated, 3, 758 synthesis, 3, 763 Chromium, tetrachloro-antiferromagnetic, 3, 761 ferromagnetic magnetic properties, 3,7559 optical properties, 3,759 structure, 3,759 solvated, 3. 758 synthesis. 3, 759 Chromium, tetrachlorooxy-tetraphenylarsenate stereochemistry, 1,44 Chromium, tetrahalo-, 3,889 Chromium, tetrakis(dioxygen)-stereochemistry, 1,94 Chromium, triamminediperoxy-structure. 1, 78 Chromium, tricyanodiperoxy-structure, 1, 78 Chromium, trifluoro-electronic spectra, 3, 757 magnetic properties, 3, 757 structures, 3, 757 synthesis, 3, 756 Chromium, trihalo-clcctronic spectra, 3, 764 magnetic properties, 3, 764 structure, 3, 764 synthesis, 3, 764 Chromium, tris(acetylacetone)-structure. 1, 65 Chromium, tris(bipyridyl)-... 

Tris(bipyridyl) complexes structure, 1, 63 Tris(diketonate) complexes structure, 1,65 Trisdithiolencs metal complexes synthesis, 2, 597... 

Wilson and Lyle [36] recently reported the synthesis and use of a new C2-symmetric 2,2 -bipyridyl ligand that answered these steric demands, since, associated to copper(I)salts, high diastereoselectivities and enantioselectivities trans/cis = 80/20 and 82% ee) could be achieved in the benchmark... 

The use of triphenylphosphine and 2,2 -bipyridyl disulphide in oxidation-reduction condensations has been extended to the phosphorylation of alcohols and phosphates, and to the preparation of 5 -(2-pyridyl) phosphorothioates (60) which have been used for the synthesis of pyrophosphates (see Chapter 6, Section 1). 

Organic synthesis 7 [OS 7] Formation of quaternary salts from 4,4 -bipyridyl and ethyl... 

Peter, K. and Thelakkat, M. (2003) Synthesis and characterization of bifunctional polymers carrying tris (bipyridyl)ruthenium(ll) and triphenylamine units. Macromolecules, 36, 1779-1785. 

Liu B, Yu W-L, Pei J, Liu S-Y, Lai Y-H, Huang W (2001) Design and synthesis of bipyridyl-containing conjugated polymers effects of polymer rigidity on metal ion sensing. Macromolecules 34 7932-7940... 

During cyclization with acetylene, the chiral center is maintained. This reaction has recently been extended to the synthesis of bipyridyl compounds having optically active substituents (75PC1) and provides access to chiral ligands of potential interest in transition-metal-catalyzed asymmetric catalysis. 

In an indirect synthesis of four-membered rings, xof-bipyridylnickelacyclopentane (3) was synthesized in 83% yield from bis(cycloocla-1,5-dtene)nickel(0), ,x -bipyridyl and 1,4-dibromobu-tane. The treatment of x.a -bipyridylnickeiacyclopentane (3) with either methyl acrylate or maleic anhydride triggered a reductive elimination process which gave cyclobutane in 57 and 75% yield,... 

Pyridylzinc bromide, a commercially available reagent, was used in the synthesis of a series of bipyridyl derivatives (7.20.). Activated coupling partners, such as 2-chloro-4-cyanopyridine, reacted readily at room temperature in the presence of a palladium based catalyst, while less electron deficient halopyridines were coupled at elevated temperatures.27 The same approach was also extended to the preparation of other heterobiaryls.28... 

Figure 4.6 Synthesis of chiral molecular squares 6a-d based on enantiopure linear l,l -binaphthyl-derived bipyridyl bridging ligands and /ac-Re CO)3CI corners.

A synthesis of much relevance is that of the copolymer (4-methyl, 4 -vinyl 2,2 bipyridine/styrene)-pendant tris(2,2 -bipyridyl) ruthenium(II) complex as sensitizer for water photolysis with solar irradiation [19]. 

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