Iron-Mediated Internal-Oxidant Relay Cascade Reaction: Strategy to Synthesize Fullerenooxazoles and Hydroxyfullerenyl Amides

Copper-Mediated Radical-Induced Ring-Opening Relay Cascade Carboannulation Reaction of [60]Fullerene with Cyclobutanone Oxime Esters: Access to [60]Fullerene-Fused Cyclopentanes

An unexpected copper-mediated radical-induced ring-opening relay cascade carboannulation reaction of [60]fullerene with cyclobutanone oxime esters is presented for the preparation of various Cl-/Br-incorporated [60]fullerene-fused cyclopentanes. The unique relay cascade transformation uses inexpensive copper salts as promoters and halogen sources and features simple redox-neutral conditions and a broad substrate scope, providing a practical access to a class of novel five-membered carbocycle-fused fullerenes.

Copper-mediated synthesis of fullerooxazoles from [60]fullerene and N-hydroxybenzimidoyl cyanides

A novel and efficient copper-mediated [3 + 2] heteroannulation reaction of [60]fullerene with N-hydroxybenzimidoyl cyanides has been developed for the synthesis of fullerooxazoles. A possible reaction mechanism involving unique C-CN and N-OH bond cleavages and subsequent C-OH bond formation for N-hydroxybenzimidoyl cyanides is proposed to explain the generation of fullerooxazoles. In addition, the formed fullerooxazoles can be further electrochemically transformed into amidated 1,2-hydrofullerenes.

Cu(I)-Catalyzed Synthesis of [60]Fullerene-Fused Lactams and Further Electrochemical Functionalization

A novel and efficient Cu(I)-catalyzed radical heteroannulation reaction of [60]fullerene (C₆₀) with α-bromo acetamides has been disclosed for the direct synthesis of diverse C₆₀-fused lactams. Furthermore, the formed C₆₀-fused lactams can be served as a versatile platform for further electrochemical functionalization to prepare 1,2-, 1,4-, 1,2,3,16-, and 1,4,9,25-adducts of C₆₀. In addition, a representative fullerene product has been applied as an overcoating layer of the electron-transporting layer in n-type perovskite solar cell.

Iron-Catalyzed Redox-Neutral Radical Cascade Reaction of [60]Fullerene with γ,δ-Unsaturated Oxime Esters: Preparation of Free (N-H) Pyrrolidino[2',3':1,2]fullerenes

Herein an unprecedented iron(II)-catalyzed redox-neutral radical cascade reaction of [60]fullerene with γ,δ-unsaturated oxime esters is reported for the preparation of novel free (N-H) pyrrolidino[2',3':1,2]fullerenes. The transformation undergoes an intramolecular cyclization/intermolecular cyclization/oxidation/hydrolysis cascade, and features simple operation, broad substrate scope/high functional group compatibility as well as suitable for scale-up synthesis, providing a facile and practical access to a range of free pyrrolidino[2',3':1,2]fullerenes.

Copper-Catalyzed N-H/C-H Sequential Relay Oxidative Radical Carboannulation: Construction of Diversely Substituted [60]Fullerene-Fused Tetrahydrocyclopenta[b]indoles

Reported herein is a new copper-catalyzed N-H/C-H sequential relay oxidative radical carboannulation of [60]fullerene with C2-functionalized free indoles for the direct construction of novel [60]fullerene-fused tetrahydrocyclopenta[b]indoles. The transformation shows high regioselectivity and atom economy, broad substrate scope, and good functional group tolerance, providing an efficient and practical approach to access diversely substituted fullerene-fused polycyclic derivatives from simple hydrocarbons.

Synthesis of fullerotetrahydropyridazines via the copper-catalyzed heteroannulation of [60]fullerene with hydrazides

Fullerotetrahydropyridazines have been efficiently synthesized via the copper-catalyzed reaction of [60]fullerene with hydrazides.

A Copper-Catalyzed Aerobic [1,3]-Nitrogen Shift through Nitrogen-Radical 4-exo-trig Cyclization

A novel radical [1,3]-nitrogen shift catalyzed by copper diacetate under an oxygen atmosphere (1 atm) has been developed for the construction of a diverse range of indole derivatives from α,α-disubstituted benzylamine. In this reaction, oxygen was used as a clean terminal oxidant, and water was produced as the only by-product. Five inert bonds were cleaved, and two C-N bonds and one C-C double bond were constructed in one pot during this transformation. This unique method demonstrated broad application protential for the late-stage modification of biologically active natural products and drugs. Mechanistic investigations indicate that a unique 4-exo-trig cyclization of an aminyl radical onto a phenyl ring is involved in the catalytic cycle.

Silver(i)-mediated three-component annulation reaction of [60]fullerene, sulfonylhydrazones, and nitriles: leading to diverse disubstituted [60]fullerene-fused dihydropyrroles

A novel Ag(i)-mediated three-component annulation reaction of C₆₀, sulfonylhydrazones, and nitriles is developed for the synthesis of diverse disubstituted C₆₀-fused dihydropyrroles.

Ferric perchlorate-mediated one-step reaction of [60]fullerene with primary amides for the synthesis of fullerooxazoles

The reaction of [60]fullerene with amides promoted by cheap and easily available ferric perchlorate affords a series of interesting fullerooxazole derivatives.

Preparation of a C70 Bis-heterocyclic Derivative with High Chemio- and Regioselectivity

C70 bis-heterocyclic derivative (1) bearing one oxazoline ring and one imidazoline ring with the 2 o'clock configuration is obtained with high chemio- and regioselectivity via the reaction of C70 with hydroxide and benzonitrile quenched with I2. Further study with benzylation experiment and theoretical calculations indicate that the oxazoline ring is the one first formed on the C70 cage, while the imidazoline ring is the one formed after the addition of I2 via a radical coupling reaction mechanism.

Cu(OAc)2-promoted reaction of [60]fullerene with primary amines or diamines

The Cu(OAc)₂-mediated oxidative dehydrogenative addition of easily available primary amines to C₆₀ allows the concise preparation of aziridinofullerenes. Moreover, the Cu(OAc)₂-promoted reaction of C₆₀ with diamines affords C₆₀-fused cyclic 1,2-diaminated fullerenes.

AgNO2-mediated cleavage of the N–N bond of sulfonylhydrazones and oxygen transfer: access to fulleroisoxazolines via radical cyclization with [60]fullerene

The first example involving cleavage of the N–N bond of sulfonylhydrazones is presented, and a new methodology for the synthesis of fulleroisoxazolines is developed.