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Herein, we report divergent additions of 2,2′‐diazidobiphenyls to C60 and Sc3N@Ih‐C80. In stark contrast to that of the previously reported bis‐azide additions, the unexpected cascade reaction leads to the dearomative formation of azafulleroids 2 fused with a 7‐6‐5‐membered ring system in the case of C60. In contrast, the corresponding reaction with Sc3N@Ih‐C80 switches to the C−H insertion pathway, thereby resulting in multiple isomers, including a carbazole‐derived [6,6]‐azametallofulleroid 3 and a [5,6]‐azametallofulleroid 4 and an unusual 1,2,3,6‐tetrahydropyrrolo[3,2‐c]carbazole‐derived metallofullerene 5, whose molecular structures have been unambiguously determined by single‐crystal X‐ray diffraction analyses. Among them, the addition type of 5 is observed for the first time in all reported additions of azides to fullerenes. Furthermore, unexpected isomerizations from 3 to 5 and from 4 to 5 have been discovered, providing the first examples of the isomerization of an azafulleroid to a carbazole‐derived fullerene rather than an aziridinofullerene. In particular, the isomerism of the [5,6]‐isomer 4 to the [5,6]‐isomer 5 is unprecedented in fullerene chemistry, contradicting the present understanding that isomerization generally occurs between [5,6]‐ and [6,6]‐isomers. Control experiments have been carried out to rationalize the reaction mechanism. Furthermore, representative azafulleroids have been applied in organic solar cells, thereby resulting in improved power conversion efficiencies. [ABSTRACT FROM AUTHOR]

Herein, we report divergent additions of 2,2′‐diazidobiphenyls to C60 and Sc3N@Ih‐C80. In stark contrast to that of the previously reported bis‐azide additions, the unexpected cascade reaction leads to the dearomative formation of azafulleroids 2 fused with a 7‐6‐5‐membered ring system in the case of C60. In contrast, the corresponding reaction with Sc3N@Ih‐C80 switches to the C−H insertion pathway, thereby resulting in multiple isomers, including a carbazole‐derived [6,6]‐azametallofulleroid 3 and a [5,6]‐azametallofulleroid 4 and an unusual 1,2,3,6‐tetrahydropyrrolo[3,2‐c]carbazole‐derived metallofullerene 5, whose molecular structures have been unambiguously determined by single‐crystal X‐ray diffraction analyses. Among them, the addition type of 5 is observed for the first time in all reported additions of azides to fullerenes. Furthermore, unexpected isomerizations from 3 to 5 and from 4 to 5 have been discovered, providing the first examples of the isomerization of an azafulleroid to a carbazole‐derived fullerene rather than an aziridinofullerene. In particular, the isomerism of the [5,6]‐isomer 4 to the [5,6]‐isomer 5 is unprecedented in fullerene chemistry, contradicting the present understanding that isomerization generally occurs between [5,6]‐ and [6,6]‐isomers. Control experiments have been carried out to rationalize the reaction mechanism. Furthermore, representative azafulleroids have been applied in organic solar cells, thereby resulting in improved power conversion efficiencies. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Chemical functionalization of fullerenes has been an important topic in fullerene chemistry. Herein, an unprecedented Pd‐catalyzed migration reaction of [60]fullerene with allyloxy‐tethered aryl iodides is present for the preparation of novel [60]fullerene‐fused allylbenzofurans. The use of 1,2‐bis(diphenylphosphino)benzene (DPPBz) as a ligand is crucial for the success of the transformation. The reaction shows high chemo‐ and regioselectivity, and is flexible with regard to allyl‐migration site, providing a new and efficient approach to rare [60]fullerene‐fused benzofurans. Control experiments disclose that the reaction most probably undergoes a sequential C—O bond cleavage/allyl‐migration/intermolecular cycloaddition cascade process. [ABSTRACT FROM AUTHOR]

Objective: To investigate the effects of ultrasound-guided erector spinae plane block (ESPB) on acute and chronic post-surgical pain in patients underwent video-assisted thoracoscopic lobectomy. Methods: A total of 94 patients, who underwent elective unilateral video-assisted thoracoscopic lobotomy from August 2021 to December 2021 were randomly divided into general anesthesia group (group A, n = 46) and ESPB combined with general anesthesia group (group B, n = 48) by computer. Patient controlled intravenous analgesia(PCIA) was performed in both groups after operation. The numerical rating scale(NRS) of rest and cough pain at post anesthesia care unit(PACU), 2 h, 6 h, 12 h, 24 and 48 h after operation, frequency of PCIA in 24 h after operation, frequency of rescue analgesia, patient satisfaction, adverse reactions and complications were recorded in the two groups. Incidence of chronic pain at 3 months and 6 months after operation, the effect of daily life and rating of chronic pain management measures were recorded in the two groups. Results: Compared with group A, rest and cough NRS score at 2 h, 6 h, 12 h, 24 and 48 h after surgery, frequency of PCIA use at 24 h after surgery, frequency of rescue analgesia were significantly decreased in group B (P < 0.05). There was no significant difference in NRS scores of rest and cough at PACU after operation between 2 groups after surgery at post anesthesia care unit (P > 0.05). There were no significant differences in the incidence of postoperative chronic pain between the 2 groups(P > 0.05);The effect of postoperative chronic pain on daily life and pain management measures in group B were significantly lower than those in group A(P < 0.05). Compared with group A, patients in group B had higher satisfaction degree, lower incidence of postoperative nausea and vomiting(PONV), and lower incidence of agitation during anesthesia recovery (P < 0.05). There were no pneumothorax, hematoma and toxicity of local anesthetic in the 2 groups. Conclusion: Ultrasound-guided erector spinae plane block can significantly reduce acute post-surgical pain, can not reduce the incidence of chronic post-surgical pain, but can significantly reduce the severity of chronic pain in patients underwent video-assisted thoracoscopic lobectomy. Trial registration: ChiCTR2100050313,date of registration:26/08/2021 [ABSTRACT FROM AUTHOR]

Herein a new, general and practical method for the spirocyclization of [60]fullerene through a palladium-catalyzed domino Heck/C–H activation reaction is presented. A wide range of novel [60]fullerene-fused spirocyclic derivatives can be easily and flexibly synthesized with a broad substrate scope and excellent functional-group tolerance. A plausible mechanism involving an alkyl Pd(II) species as a key intermediate has been proposed. [ABSTRACT FROM AUTHOR]

A general and practical methodology for the preparation of novel vinyl-substituted [60]fullerene-fused tetrahydrofurans/pyrans/quinolines through palladium-catalyzed decarboxylative heterocyclizations of [60]fullerene with vinylethylene/2-alkylidenetrimethylene carbonates and vinyl carbamates was developed. Without additives or ligands, the Pd(PPh3)4-catalyzed transformations undergo decarboxylative O- and N-heteroannulation processes to efficiently furnish structurally diverse [60]fullerene-fused heterocyclic derivatives. [ABSTRACT FROM AUTHOR]

Described here is the first example of solvent-promoted catalyst-free N-incorporation multicomponent domino reaction for the direct construction of novel π-extension [60]fullerene-fused dihydrocarbolines from simple hydrocarbons. This unprecedented transformation is proposed to proceed by a sequential N-incorporation/[4+2] cycloaddition/elimination process, involving multiple types of bond cleavage and formation in a single chemical operation. Mechanistic studies uncover that solvent is crucial for the success of the transformation, and multiple solvent-aided deprotonation and proton transfer are involved as key steps. [ABSTRACT FROM AUTHOR]

The unique reactivity and synthetic applications of oxime acetate derivatives with N, O and S substituents at the α-position are disclosed for the first time, which leads to 2-substituted fulleropyrrolidines and mono- and disubstituted 1-fulleropyrrolines via copper-catalyzed redox-neutral N-heteroannulation reactions with C60. This transformation is operationally simple and has a broad substrate scope and good functional group tolerance. Theoretical calculations at the level of B3LYP/6-31G(d) were performed to elucidate the chemoselectivity of the reaction. [ABSTRACT FROM AUTHOR]

A new, operationally simple one-pot method has been developed for the regioselective synthesis of a series of novel 4-olefinated dihydropyridines bearing various functional groups from the reaction of pyridine, acylacetamides, and sulfuryl chlorides under mild conditions. In this multicomponent process, subsequent the activation of pyridine by sulfuryl chloride/nucleophilic addition of acylacetonitrile formed in situ/enolization/sulfonylation leads to the formation of final products. [ABSTRACT FROM AUTHOR]

A novel Ag(i)-induced three-component annulation reaction of [60]fullerene with sulfonylhydrazones and nitriles has been developed for the efficient synthesis of diverse disubstituted [60]fullerene-fused dihydropyrroles. The reaction exhibits a broad substrate scope and excellent functional-group tolerance, and also allows for the synthesis of fullerene-bound macromolecules. [ABSTRACT FROM AUTHOR]

An unprecedented AgNO2-mediated novel transformation of sulfonylhydrazones with [60]fullerene to various fulleroisoxazolines has been developed. The new chemistry of sulfonylhydrazones involving the cleavage of the N–N bond in synthetic application is first disclosed. Silver nitrite acts as the reaction initiator and the oxygen source in this unique transformation. This reaction is easy to perform, and exhibits a remarkably wide substrate scope under mild conditions. [ABSTRACT FROM AUTHOR]

A convenient andefficient Cu(OAc)2-mediated N-heteroannulationreaction of [60]fullerene with N-sulfonylated o-amino-aromatic methyl ketones or O-alkyloximes has been reported for the synthesis of novel and scarce [60]fullerene-fusedtetrahydroazepinones and -azepinoniminesin a highly selective manner. Moreover, a possible mechanism involvingtwo pathways is proposed on the basis of the experimental observations. [ABSTRACT FROM AUTHOR]

Abstract: An alternative and efficient method to stereoselectively synthesize oxazolo[3,4-b]tetrahydroisoquinolin-3-ones via a Pictet–Spengler reaction promoted by Lewis acid TMSOTf from readily available (S)-4-benzyl-2-oxazolidinone with various aromatic, aliphatic, and cyclic aldehydes under room temperature is described. [Copyright &y& Elsevier]

A one-pot, three-component coupling reaction of pyridine, β-keto amides, and sulfonyl chlorides yields 4-alkenyl-1,4-dihydropyridines under mild conditions via sequential activation of pyridine by the sulfonyl chloride and nucleophilic addition of in situ generated acylacetonitrile. [ABSTRACT FROM AUTHOR]

A novel Ag(I)-induced three-component annulation reaction of C60-fullerene with sulfonylhydrazones and nitriles is developed for the efficient synthesis of diverse disubstituted C60-fullerene-fused dihydropyrroles. [ABSTRACT FROM AUTHOR]

An unprecedented AgNO2-mediated novel transformation of sulfonylhydrazones with [60]fullerene to various fulleroisoxazolines is presented. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "Diastereoselective Synthesis of Oxazolo (3,4-b) Tetrahydroisoquinolin-3-ones via Lewis Acid TMSOTf (Trimethylsilyl Trifluoromethanesulfonate)- Mediated Pictet: Spengler Reaction" published in the periodical "Tetrahedron: Asymmetry."

The reaction involves cleavage of C-H and O-H bonds and formation of C-C and C-O bonds. [ABSTRACT FROM AUTHOR]

Fullerenyl boronic esters have been prepared by a ferric perchlorate-promoted reaction of [60]fullerene with various arylboronic acids. The obtained fullerenyl boronic esters could undergo further functionalization with diols to afford C60-fused dioxane/dioxepane derivatives. A possible reaction mechanism for the formation of fullerenyl boronic esters has been proposed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fullerenol as MALDI matrix analyzed organic compounds with low background interference, high sensitivity and excellent reproducibility. • Quantification of saccharin sodium in different real samples was performed by MALDI-MS with fullerenol as matrix. • The quantitative analytical results demonstrated low matrix effect, good linear relationship, excellent precision and accuracy. Due to the strong background interferences in the low-mass region and poor reproducibility of conventional organic matrices, it is of great importance to develop a novel matrix for matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) to qualitatively and quantitatively analyze small molecules. In this work, water-soluble fullerenol C 60 (OH) 24–26 was selected as a MALDI matrix for the analysis of low-molecular-weight compounds in consideration of optical absorption property, water solubility and stability. Compared with the traditional matrices, fullerenol demonstrated lower background interference and stronger peak intensity. In addition, the hydrophilic fullerenol could avoid the heterogeneous crystallization in sample preparation, increase the reproducibility and sensitivity of MALDI-MS, and ameliorate quantitative analysis of small molecules. With saccharin as model analyte, quantitative analysis was carried out using fullerenol as matrix. The results demonstrated satisfying reproducibility and good tolerance to salt. The limit-of-detection of the quantitative analysis was as low as 4 pmol, and the linear range is 1–100 μg mL−1 with R2 greater than 0.99. The analytical results also showed excellent precision and accuracy, low matrix effect and good recovery rate. Fullerenol as a potential matrix was further validated in the quantification of saccharin sodium in different real food samples, such as nuts and drinks. This work not only confirms the potential of fullerenol for the quantitative analysis in food field, but also provides a new technique for rapid analysis of small molecules. [ABSTRACT FROM AUTHOR]

This paper proposed a finite time convergence global sliding mode control scheme for the second-order multiple models control system. Firstly, the global sliding surface without reaching law for a single model control system is designed and the tracking error finite time convergence and global stability are proved. Secondly, we generalize the above scheme to the second-order multimodel control system and obtain the global sliding mode control law. Then, the convergent and stable performances of the closed-loop control system with multimodel controllers are proved. Finally, a simulation example shows that the proposed control scheme is more effective and useful compared with the traditional sliding mode control scheme. [ABSTRACT FROM AUTHOR]

In order to solve the problem that theoretical teaching and practice of knowledge are simple in the course of Measurement and Control, a teaching experiment platform was developed based on real industrial production process. This platform combines the advantages of televisions with the structure of general machines. Meanwhile, the platform uses the operating system of uC/OS--II, the controlling frame of STM32 and the sensor module of camera, encoder and optical grating ruler. It effectively broadens the horizon of students and lecture content, improves their ability of programming and designing. Therefore, the objectives of the lecture are naturally achieved. [ABSTRACT FROM AUTHOR]