Cu-Catalyzed [3 + 3] Annulation for the Synthesis of Pyrimidines via β-C(sp<sup>3</sup>)–H Functionalization of Saturated Ketones
作者:Jun-Long Zhan、Meng-Wei Wu、Fei Chen、Bing Han
DOI:10.1021/acs.joc.6b02181
日期:2016.12.2
A novel, efficient, and facile approach for the synthesis of structurally important pyrimidines has been successfully developed by Cu-catalyzed and 4-HO-TEMPO-mediated [3 + 3] annulation of commercially available amidines with saturated ketones. This method provides a new protocol for the synthesis of pyrimidines by a cascade reaction of oxidative dehydrogenation/annulation/oxidative aromatization
Stable Ion Study of Regioisomeric Carboxonium-Substituted Pyrenium Ions: Directive Effects, Charge Delocalization Mode, and Conformational Aspects
作者:Kenneth K. Laali、Takao Okazaki、Poul Erik Hansen
DOI:10.1021/jo0001939
日期:2000.6.1
studied by low-temperature NMR at 500 MHz. Conformational aspects of the carboxonium group in various regioisomers are addressed by a combination of NOED spectra and 2D-NMR and AM1 calculations. Chargedelocalization pathways are gauged and compared on the basis of the magnitude of Deltadelta (13)C values.