Single Electron Transfer-Promoted Photochemical Reactions of Secondary N-Trimethylsilylmethyl-N-benzylamines Leading to Aminomethylation of Fullerene C60

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• 作者：Suk Hyun Lim ; Ho Cheol Jeong ; Youngku Sohn ; Young-Il Kim ; Dae Won Cho ; Hee-Jae Woo ; Ik-Soo Shin ; Ung Chan Yoon ; Patrick S. Mariano
• 刊名：Journal of Organic Chemistry
• 出版年：2016
• 出版时间：March 18, 2016
• 年：2016
• 卷：81
• 期：6
• 页码：2460-2473
• 全文大小：668K
• ISSN：1520-6904

文摘

Photoreactions between C₆₀ and secondary N-trimethylsilylmethyl-N-benzylamines were explored to evaluate the feasibility of a new method for secondary aminomethylation of electron acceptors. The results show that photoreactions of C₆₀ with these secondary amines in 10% EtOH-toluene occur to form aminomethyl-1,2-dihydrofullerenes predominantly through a pathway involving single electron transfer (SET)-promoted formation of secondary aminium radicals followed by preferential loss of the α-trimethylsilyl group. The aminomethyl radicals formed in this manner then couple with C₆₀ or C₆₀^•– to form radical or anion precursors of the aminomethyl-1,2-dihydrofullerenes. In contrast to thermal and photochemical strategies developed previously, the new SET photochemical approach using α-trimethylsilyl-substituted secondary amines is both mild and efficient, and as a result, it should be useful in broadening the library of substituted fullerenes. Moreover, the results should have an impact on the design of SET-promoted C–C bond forming reactions. Specifically, introduction of an α-trimethylsilyl group leads to a change in the chemoselectivity of SET-promoted reactions of secondary amines with acceptors that typically favor aminium radical N–H deprotonation, leading to N–C bond formation. Finally, symmetric and unsymmetric fulleropyrrolidines are also generated in yields that are highly dependent on the electronic properties of arene ring substituents in amines, irradiation time, and solvent.