Click Chemistry in Cu^I-zeolites:  The Huisgen [3 + 2]-Cycloaddition

Abstract

[reaction: see text] CuI-exchanged solids based on zeolite materials were investigated for the first time as catalysts in organic synthesis. The catalytic potential of these materials was evaluated in the Huisgen [3 + 2]-cycloaddition. Five CuI-exchanged zeolites were examined and CuI-USY proved to be a novel and efficient heterogeneous ligand-free catalyst for this "click chemistry"-type transformation.

Metal-doped Zeolites as Green Catalysts for Organic Synthesis

“…Moreover, all examined solvents including protic solvents proved suitable for this reaction, but toluene was the most effective and the cleanest at r. t. (Fig. 3) [20].…”

Regiospecific synthesis of 1-(5-hydroxy-5-trichloromethyl-4,5-dihydroisoxazole-3-methylene)-5-phenyl-1H-1,2,3-triazoles

“…All triazoles displayed a C-H stretching absorption in the 1214-1673 cm -1 range and a C-halogen stretching absorption in the 667-806 cm-1 range. The classical cycloaddition of phenylacetylene with benzyl azide without any catalyst, does not take place in toluene at room temperature, 19 or leads to a 1:1 mixture of regioisomers after a prolonged reaction time at reflux. 19 In addition, it is known that alkynes with an electronwithdrawing functional group favor the irreversible Huisgen cycloaddition reaction of azides and alkynes.…”

“…The classical cycloaddition of phenylacetylene with benzyl azide without any catalyst, does not take place in toluene at room temperature, 19 or leads to a 1:1 mixture of regioisomers after a prolonged reaction time at reflux. 19 In addition, it is known that alkynes with an electronwithdrawing functional group favor the irreversible Huisgen cycloaddition reaction of azides and alkynes. 20 It was also recently reported that it is possible to impart some regioselectivity into these thermal cycloaddition reactions by utilizing sterically or electronically biased alkynes.…”

Highly Active and Reusable Kenaf Cellulose Supported Bio-Poly(hydroxamic acid) Functionalized Copper Catalysts for C–N Bond Formation Reactions

“…Namely, MOF-99 (metal organic framework) (Nguyen et al 2012), polystyrene supported Cu(I)-imidazole complex (Li et al 2012), silica sulfuric acid (Wang et al 2009), phosphate-impregnated titania (Nath and Chaudhuri 2009), PSSA (polystyrenesulfonic acid) (Polshettiwar and Varma 2007), Amberlyst-15 (Das and Chowdhury 2007), MCM-41 (Mobil composition of matter) immobilized heteropoly acids (Xie et al 2013), HY zeolite (Jeganathan et al 2014), polystyrene-supported DABCO (1,4-diazabicyclo[2.2.2]octane), and TBD (1,5,4,0]dec-5-ene) (Sodhi et al 2015;Yu and Xu 2015), silica-bonded imidazolium-sulfonic acid chloride (SBISAC) (Moosavi-Zare et al 2015), zeolites (Chassaing et al 2007), polymers (Yamada et al 2012), non-magnetic and magnetic supported Cu(I) (Megia-Fernandez et al 2010), silica (Mnasri et al 2015), and TiO2-nanotube (Faraji et al 2016) all showed good catalytic activity. However, they do not completely fulfill the economic and sustainable protocols involved in the development of green processes.…”