1,3-Dipolar cycloadditions alkynes

Santoyo-Gonzdlez F, Hernandez-Mateo F (2007) Azide-Alkyne 1,3-Dipolar Cycloadditions a Valuable Tool in Carbohydrate Chemistry. 7 133-177 Saraboji K, see Ponnuswamy MN (2006) 3 81-147... 

F. Santoyo-Gonzalez and F. Hemandez-Mateo, Azide-alkyne 1, 3-dipolar cycloadditions A valuable tool in carbohydrate chemistry, Top. Heterocycl. Chem., 7 (2007) 133-177. 

S. Dedola, S. A. Nepogodiev, and R. A. Field, Recent applications of the Cul-catalysed Huisgen azide-alkyne 1,3-dipolar cycloaddition reaction in carbohydrate chemistry, Org. Biomol. Chem.., 5 (2007) 1006-1017. 

The Cu -catalysed azide alkyne 1,3-dipolar cycloaddition (CuAAC) click chemistry has also been used to synthesize a library of a,/ -D-glucopyranosyl triazoles (iii). The synthesized triazoles proved to be potential glycosidase inhibitors [15]. 

Cantel S, Le Chevalier IA, Scrima M et al (2008) Synthesis and conformational analysis of a cyclic peptide obtained via i to i + 4 intramolecular side-chain to side-chain azide-alkyne 1,3-dipolar cycloaddition. J Org Chem 73 5663-5674... 

Click chemistry has also been applied in carbohydrate chemistry. Thus, Huisgen cyclization involving a sugar azide or alkyne has been extensively used for the preparation of a wide range of carbohydrates bearing a triazole moiety in different positions. In this volume, Santoyo Gonzalez and Herndndez-Mateo present a contribution concerning azide-alkyne 1,3-dipolar cycloadditions, mostly devoted to non-anomeric positions. 

Azide-Alkyne 1,3-Dipolar Cycloadditions a Valuable Tool in Carbohydrate Chemistry... 

The utility of the Paal-Knorr reaction allows it to stiU remain at the forefront of organic chemistry for the preparation of highly complex substrates and drug-like compounds. The Paal-Knorr reaction was used to synthesize iV-aryl pyrroles 25 with an azide group on the aryl ring. These substrates were subsequently employed in a tandem azide-alkyne 1,3-dipolar cycloaddition reaction to synthesize medicinally important molecules with a diazepine scaffold 27 (14OL560). 

Expanding on the work by Francis and coworkers to target Tyr residues on the exterior of TMV for chemical conjugation, Wang and coworkers have utilized copper-catalyzed azide-alkyne 1,3-dipolar cycloaddition, or click chemistry, in combination with the diazonium coupling... 

A range of indolo(triazolo)-l,4-diazepine derivatives 104 were obtained by a microwave-heated three-component reaction involving tandem N-alkylation of indole 101 with epichlorohydrin 102, ring-opening of the epoxide with azide 103, and intramolecular azide-alkyne 1,3-dipolar cycloaddition reactions (13BJO401). Fused triazolodiazepinones were obtained via azide-alkyne 1,3-dipolar cycloaddition followed by lactamization (13JHC430). 

A four-component reaction involving tandem indium chloride-catalyzed cyclocondensation of ammonium acetate 124, glyoxal derivatives 125,2-azidobenzaldehyde derivatives 126, and propargylamines 127 followed by intramolecular azide-alkyne 1,3-dipolar cycloaddition reactions afforded highly functionalized benzo-imidazo-triazolodiazepines 128 (130L4492). 

A one-pot copper(I)-catalyzed tandem azidation of ort/io-bromo-benzyl(propargyl)amines and an azide-alkyne 1,3-dipolar cycloaddition reaction, afforded [l,2,3]-triazolo[l,5-a][l,4]benzodiazepines (13T4331). 

Around the time that the copper-catalyzed azide-alkyne 1,3-dipolar cycloaddition (CuAAC) click reaction was emerging as a powerful tool for the constmction [110, 111] of MIMs, we became interested in using this reaction to prepare polyrotaxanes. Our first attempt turned up compelling evidence that the folded solid-state stmctures described in Sect. 2 also persist to a large extent in solution. 

To highlight the utility of the enantioselective azidation further, transformations of the resulting azides were carried out (Scheme 15.11). For example, an a-azido ester could be converted smoothly into a-amino ester by palladium-catalyzed hydrogenolysis, which may provide a useful method for the synthesis of highly substituted cx-amino acid derivatives. On the other hand, the copper-catalyzed azide-alkyne 1,3-dipolar cycloaddition (CuAAC), as a click reaction, has been... 

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