Photoreactions of Sc3N@C80 with Disilirane, Silirane, and Digermirane: A Photochemical Method to Separate Ih and D5h Isomers

Under photoirradiation, Sc3N@Ih-C80 reacted readily with disilirane 1, silirane 4, and digermirane 7 to afford the corresponding 1:1 adducts, whereas Sc3N@D5h-C80 was recovered without producing those adducts. Based on these results, we described a novel method for the exclusive separation of Ih and D5h isomers of Sc3N@C80. The method includes three procedures: selective derivatization of Sc3N@Ih-C80 using 1, 4, and 7, facile HPLC separation of pristine Sc3N@D5h-C80 and Sc3N@Ih-C80 derivatives, and thermolysis of Sc3N@Ih-C80 derivatives to collect pristine Sc3N@Ih-C80. In addition, laser flash photolysis experiments were conducted to elucidate the reaction mechanism. Decay of the transient absorption of 3Sc3N@Ih-C80* was observed to be enhanced in the presence of 1, indicating the quenching process. When Sc3N@D5h-C80 was used, the transient absorption was much less intensive. Therefore, the quenching of 3Sc3N@D5h-C80* by 1 could not be confirmed. Furthermore, we applied time-dependent density functional theory (TD-DFT) calculations of the photoexcited states of Sc3N@C80 to obtain insights into the reaction mechanism

Functionalization of Endohedral Metallofullerenes with Reactive Silicon and Germanium Compounds

Exohedral derivatization of endohedral metallofullerenes (EMFs) has been exploited as a useful method for characterizing the structural and chemical properties of EMFs, and for functionalizing them for potential applications. The introduction of heteroatoms, such as electropositive silicon atoms, to fullerene cages is a novel functionalization method that remarkably affects the electronic characteristics of fullerenes. This review comprehensively describes the results of the reactions of monometallofullerene, dimetallofullerene, and trimetallic nitride template EMFs with disilirane, silirane, silylene, and digermirane, which afforded the corresponding silylated and germylated fullerenes. Several examples emphasize that exohedral functionalization regulates the dynamic behaviors of the encapsulated metal atoms and clusters in the fullerene cages. The electronic effects of silyl and germyl groups are represented by comparing the redox properties of silylated and germylated EMFs with those of other EMFs derivatized with carbon-atom-based functional groups

Photochemical addition of silirane to endohedral metallofullerene: Electronic properties of carbosilylated Sc₃N@<i>I_h</i>-C₈₀

<p>The photochemical reaction of Sc₃N@<i>I_h</i>-C₈₀ with silirane <b>1</b> produced the corresponding carbosilylated derivatives. The electrochemical studies of [5,6]-adducts indicate that carbosilylation is an effective method for tuning moderately the electronic characteristics of Sc₃N@<i>I_h</i>-C₈₀. Density functional theory calculations were also conducted to offer a theoretical basis for the electronic properties of carbosilylated derivatives.</p

General anesthetic management of a patient with multiple chemical sensitivity for oral surgery: a case report

Abstract Background Multiple chemical sensitivity (MCS) was first described in 1987. It is said that MCS is caused by neurological and immunological mechanisms in addition to psychosomatic mechanisms. When performing general anesthesia in patients with MCS, careful perioperative management is necessary. Case presentation The patient was a 32-year-old man. Wisdom teeth extraction under general anesthesia was scheduled under the diagnosis of pericoronitis. In 2015, he was diagnosed with MCS. Since then, he experienced sweating and urticaria when exposed to artificial fragrances. We prepared the surgical surroundings by letting the patient touch every possible equipment. In selecting the anesthetic drugs, a completely intravenous route was selected because of the possibility that artificial fragrance of inhalation anesthesia could induce symptoms. There was no allergic reaction during the preoperative period. Conclusions It is important to reduce psychological burden of patient and to eliminate all possible reactive substances to prevent symptom onset