Cu(OAc)₂-Mediated Reaction of C₆₀ with Ureas for the Preparation of Fulleroimidazolidinones

Abstract

The Cu(OAc)2-mediated intermolecular diamination reaction of C60 with ureas allows the concise and efficient preparation of fulleroimidazolidinones involving the cleavage of two N-H bonds and formation of two C-N bonds. Both dialkylated and diarylated fulleroimidazolidinones can be synthesized using this method.

Copper-Catalyzed Functionalizations of C60 with Amino Alcohols

“…In contrast to the widely investigated C - and O -centered radicals, the addition of N -centered radicals to fullerenes has received less attention . We have been interested in exploring the functionalization of C 60 through the addition of N -centered radicals and have developed hypervalent iodine reagent/I 2 system-mediated or Cu­(I/II)-catalyzed/promoted reactions of C 60 with amine compounds. A strategy for the annulation of C 60 through an N -centered radical addition has been proposed.…”

“…A strategy for the annulation of C 60 through an N -centered radical addition has been proposed. Addition of an N -centered radical to C 60 produces the fullerenyl radical, which is oxidized to form the diradicals or fullerenyl cation followed by an intramolecular radical coupling or attack by the tethered nucleophilic atom to afford different kinds of heterocycle-fused fullerene derivatives. , On the basis of these results, we envision that an aminooxygenation of fullerene may occur using amino alcohols as the reactants. Currently, only a handful of reports describe the cyclic aminooxygenation reaction to access heterocycles containing both oxygen and nitrogen atoms.…”

Cu(OAc)2-Mediated Reaction of [60]Fullerene with Aldehydes and Primary Amines for the Synthesis of Fulleropyrrolines

“…Chemical modification of fullerenes to introduce versatile functional groups onto fullerene skeletons has received extensive attention over the past decades because the functionalization of fullerenes not only increases their solubilities in water and/or polar organic solvents but also tunes their energy levels and packing structures, which would expand their applications in many fields, such as material science, biological application, nanotechnology, and so on. , Radical addition reactions induced by transition metal salts in place of traditional peroxide or light have proven to be a powerful tool to functionalize fullerenes, and numerous novel fullerene derivatives with different structural motifs have been successfully prepared under the assistance of diverse types of transition metal salts. Among the reported transition metal salts, the Cu­(II)/Cu­(I) salts have recently attracted special attention among the scientific community due to their low toxicity, easy availability, inexpensive price, and insensitivity to air and water. , The first example for the use of Cu­(II)/Cu­(I) salts to functionalize fullerenes was reported by Wang’s group through the Cu­(OAc) 2 -mediated reaction of [60]­fullerene (C 60 ) with ketonic compounds . Since then, CuCl 2 /CuBr 2 and CuBr/CuI were also successfully employed to functionalize fullerenes .…”

“…Since then, CuCl 2 /CuBr 2 and CuBr/CuI were also successfully employed to functionalize fullerenes . In comparison with the extensively investigated Mn­(III) , and Fe­(III) , salts, the Cu­(II)/Cu­(I) salts are still underdeveloped because only a few papers in this research field were reported. , Further exploration and development of new types of fullerene reactions promoted by the Cu­(II)/Cu­(I) salts is still demanding.…”

Reaction of C60 with Inactive Secondary Amines and Aldehydes and the Cu(OAc)2-Promoted Regioselective Intramolecular C–H Functionalization of the Generated Fulleropyrrolidines

“…As we know, in contrast to α-amino acids or α-amino esters, ordinary secondary amines are much more easily available. As a continuation of our interest in fullerene chemistry, herein we described a concise protocol for the highly stereoselective synthesis of fulleropyrrolidines through thermal reaction of C 60 with inactive secondary amines and aromatic aldehydes (Scheme ).…”