Triazole complexes ruthenium

Furthermore, ruthenium bipyridyl and tripyridyl complexes bearing a terminal alkyne reacted with azides affording triazole complexes [36]. 

The 1,5-disubstituted 1,2,3-triazole (yvn-triazole) regioisomer may be regioselectively synthesized by using magnesium acetylides1251 or the more recently discovered catalysis by ruthenium complexes.1261 Almost equimolar syn- and antt-triazole mixtures are obtained by heating neat mixtures of the corresponding azides and alkynes at elevated temperatures (Scheme 7.2).[27]... 

Ruthenium(II) complexes were recently reported to catalyze the cycloaddition reaction of terminal as well as internal aUcynes, forming 1,5-di-substituted and 1,4,5-trisubstituted-1,2,3-triazoles which caimot be obtained... 

As carboxylic acid additives increased the efficiency of palladium catalysts in direct arylations through a cooperative deprotonation/metallation mechanism (see Chapter 11) [45], their application to ruthenium catalysis was tested. Thus, it was found that a ruthenium complex modified with carboxylic acid MesC02H (96) displayed a broad scope and allowed for the efficient directed arylation of triazoles, pyridines, pyrazoles or oxazolines [44, 46). With respect to the electrophile, aryl bromides, chlorides and tosylates, including ortho-substituted derivatives, were found to be viable substrates. It should be noted here that these direct arylations could be performed at a lower reaction temperatures of 80 °C (Scheme 9.34). 

In 2005, ruthenium cyclopentadienyl complexes were found to catalyze the formation ofthe complementary 1,5-disubstituted triazole from azides and terminal... 

Kumar M, DePasquale J, White NJ, ZeUer M, Papish ET. Ruthenium complexes of triazole-based scorpionate ligands transfer hydrogen to substrates under base-free conditions. OrganometalUcs. 2013 32 2135-2144. 

Iridium dimer complexes catalyse the 3 + 2-cycloaddition reactions of organic azides with bromoalkynes to furnish 1,5-disubstituted 4-bromo-1,2,3-triazoles in excellent yields under mild conditions. Ruthenium(II)-azido complexes undergo 3 + 2-cycloaddition reactions with strained cyclooctynes under ambient temperatures. No reaction was observed with non-activated terminal or internal alkynes under the same conditions. Dithioic acid copper catalysts (60) catalyse the 3 + 2-cycloaddition reaction of azides with alkynes to form 1,4-disubstituted-1,2,3-triazoles in various solvents and under various temperatures. Thermal Huisgen 3 + 2-cycloaddition reactions of azides and bis(trimethylsilyl)acetylene formed 4,5-bis(trimethylsilyl)-l/f-l,2,3-triazoles in low to high yields (15-95%). The Cu(I)-catalysed 3 + 2-cycloaddition... 

The regioselective formation of 1,4- and 1,5-disubstituted 1,2,3-triazoles can be accomplished by CuAAC reactions and ruthenium-catalyzed azide-alkyne [3+2] cycloaddition (RuAAC) reactions, respectively [69, 70]. Fokin and coworkers demonstrated that ruthenium complexes such as Cp RuCl(PPh3)2... 

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