Nanoparticle‐Catalysed 1,3‐Dipolar Cycloadditions

Abstract

The 1,3-dipolar cycloadditions of azomethine-ylides and-imines, nitrones, nitrilimines, and azides catalysed by inorganic nanoparticles are described. Emphasis is given to the nanometric catalysts involved, their structure, characterisation,

Recent Progress in Heterocycle Synthesis: Cyclization Reaction with Pyridinium and Quinolinium 1,4-Zwitterions

“…Chemists are becoming increasingly focused on developing efficient synthetic approaches for heterocyclic frameworks, where minimizing the number of synthetic steps, maximizing synthesis efficiency, and reducing side reactions are important evaluation criteria [ 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 ]. Among various synthetic strategies, dipolar cyclization reactions have become one of the most favored methods for the construction of functionalized heterocyclic compounds [ 16 , 17 , 18 , 19 , 20 ]. The development of new types of dipoles and the exploration of their potential applications in cyclization reactions are new challenges in the field of modern organic chemistry [ 21 , 22 , 23 , 24 , 25 , 26 , 27 ].…”

Spiro‐2‐oxindoles via 1,3‐dipolar cycloadditions. A decade update

“…The main routes to the spirooxindole skeletons rely upon spirocyclisation and cycloaddition protocols [13–15] . By limiting ourselves to the cycloadditive approach, it can be recognised that a number of reports has appeared concerning the recent developments of 1,3‐dipolar cycloadditions including their synthetic versatility, [16] the use of non‐conventional solvents like ionic liquids, [17] water [18] or aqueous media [19] and the application of inorganic nanocatalysts [20,21] . Furthermore, the 1,3‐dipolar cycloadditions to 2‐oxindoles bearing a C=X double bond in the 3‐position represent a fertile field in the synthesis of a variety of spirooxindoles [15] .…”

Stereoselective synthesis of spirocyclic pyrrolidines/pyrrolizidines/pyrrolothiazolidines using l-proline functionalized manganese ferrite nanorods as a novel heterogeneous catalyst

“…[25][26][27] Moreover, Lproline MNR-supported catalysts which were synthesized by coating MnCoCu ferrite nanorods with proline showed high surface areas, high catalyst loading capacity, reusability, dispersion, excellent yields and superior stability. [28][29][30] In this work, a novel MCCFe 2 O 4 @L-proline recyclable heterogeneous nanorod catalyst was prepared; it is promising due to its easy operation, low cost, low temperature, and controllable conditions, the high reactivity of the obtained products and the prevention of undesired side-product formation (Scheme 1). In continuation of our research and considering the above reasons related to multicomponent 1,3-dipolar cycloaddition reactions and our ongoing program for the synthesis of complex organic compounds based on green chemistry, [31][32][33][34][35][36][37] herein, we were fascinated by the possibility of using green and nano chemistry to design an efficient, reusable and diastereoselective catalyst for the synthesis of spiro-pyrrolidines/pyrrolizidines and pyrrolothiazole derivatives via a one-pot process involving azomethine ylides using MCCFe 2 O 4 @L-proline MNRs (Scheme 2).…”

“…25–27 Moreover, l -proline MNR-supported catalysts which were synthesized by coating MnCoCu ferrite nanorods with proline showed high surface areas, high catalyst loading capacity, reusability, dispersion, excellent yields and superior stability. 28–30 In this work, a novel MCCFe 2 O 4 @ l -proline recyclable heterogeneous nanorod catalyst was prepared; it is promising due to its easy operation, low cost, low temperature, and controllable conditions, the high reactivity of the obtained products and the prevention of undesired side-product formation ( Scheme 1 ).…”