Selective Functionalization of Fullerenes withN,N-Dihalosulfonamides as an N1Unit: Versatile Syntheses of Aza[60]fulleroids and Aziridino[60]fullerenes and their Application to Photovoltaic Cells

An open-cage bis[60]fulleroid as an electron transport material for tin halide perovskite solar cells

An open-cage bis[60]fulleroid (OC) was applied as an electron transport material (ETM) in tin (Sn) halide perovskite solar cells (PSCs). Due to the reduced offset between the energy levels of Sn-based perovskites and ETMs, the power conversion efficiency (PCE) of Sn-based PSCs with OC reached 9.6% with an open-circuit voltage (VOC) of 0.72 V. Additionally, OC exhibited superior thermal stability and provided 75% of the material without decomposition after vacuum deposition. The PSC using vacuum-deposited OC as the ETM could afford a PCE of 7.6%, which is a big leap forward compared with previous results using vacuum-deposited fullerene derivatives as ETMs.

Intramolecular C-H Amination of N-Alkylsulfamides by tert-Butyl Hypoiodite or N-Iodosuccinimide

1,3-Diamines are an important class of compounds that are broadly found in natural products and are also widely used as building blocks in organic synthesis. Although the intramolecular C-H amination of N-alkylsulfamide derivatives is a reliable method for the construction of 1,3-diamine structures, the majority of these methods involve the use of a transition-metal catalyst. We herein report on a new transition-metal-free method using tert-butyl hypoiodite (t-BuOI) or N-iodosuccinimide (NIS), enabling secondary non-benzylic and tertiary C-H amination reactions to proceed. The cyclic sulfamide products can be easily transformed into 1,3-diamines. Mechanistic investigations revealed that amination reactions using t-BuOI or NIS each proceed via different pathways.

Synthesis of homoazafullerene [C59N(CH2)]R and azahomoazafullerene [C59N(NH)]R

The selective insertion of a CH₂ or NH group is achieved through the PCl₅ induced reaction of a CH₂OH or NHOH group, respectively.

Regioselective Diels–Alder reaction to open-cage ketolactam derivatives of C60

Open-cage ketolactam fullerenes reacted with dienes on the rim of the orifice both regio- and endo-selectively, which were confirmed by 2D INADEQUATE ¹³C NMR of ¹³C enriched material/HMBC spectra as well as the theoretical calculations.

Regioselective addition of Grignard reagents to tosylazafulleroid and derivatization to 1,2-disubstituted [60]fullerene

Grignard reaction with tosylazafulleroid selectively gave tosyl aminylfullerene with the relatively rare 1,2-configuration, via [5,6] ring-closure and CN-bond scission.

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.

TsOH-mediated reaction of aziridinofullerene with diols for the preparation of fullerene-fused dioxygenated ring compounds

Reaction of aziridinofullerene with diols promoted by p-toluenesulfonic acid affords various fullerene-fused dioxygenated ring compounds with six- to ten-membered heterocycles.

Oxidative deamination of azafulleroids into C60 by peracids

Oxidation of azafulleroids with peracids regenerate C₆₀via oxidation of the bridged nitrogen, depending on the basicity of N-substituents.

CuCl2-mediated reaction of [60]fullerene with amines in the presence or absence of dimethyl acetylenedicarboxylate: preparation of fulleropyrroline or aziridinofullerene derivatives

The CuCl2-mediated three-component reaction of C60 with amines and dimethyl acetylenedicarboxylate afforded the fulleropyrrolines in moderate yields. Furthermore, the CuCl2-mediated oxidative [2 + 1] reaction of C60 with aromatic amines bearing a strong electron-withdrawing group provided the aziridinofullerenes and the selective cis-1-bisaziridinofullerenes.