443682-79-9Relevant articles and documents
Tf2NH-Catalyzed Formal [3 + 2] Cycloaddition of Ynamides with Dioxazoles: A Metal-Free Approach to Polysubstituted 4-Aminooxazoles
Zhao, Yingying,Hu, Yancheng,Wang, Chunxiang,Li, Xincheng,Wan, Boshun
, p. 3935 - 3942 (2017/04/11)
An unprecedented Tf2NH-catalyzed formal [3 + 2] cycloaddition of ynamides with dioxazoles was developed to construct various polysubstituted 4-aminooxazoles. This approach features a metal-free catalytic bimolecular assembly of oxazole motifs, a low-cost catalyst, exceptionally mild reaction conditions, a very short reaction time, a broad substrate scope, and high efficiency. This metal-free protocol may find applications in pharmaceutical-oriented synthesis.
5,5-Dimethyl-1,4,2-dioxazoles as versatile aprotic hydroxamic acid protecting groups
Couturier, Michel,Tucker, John L.,Proulx, Caroline,Boucher, Ghislain,Dube, Pascal,Andresen, Brian M.,Ghosh, Arun
, p. 4833 - 4838 (2007/10/03)
5,5-Dimethyl-1,4,2-dioxazoles are readily installed by transketalization of 2,2-diethoxypropane, where both the NH and OH moieties are protected in a nonprotic form. The dioxazoles are stable to a wide variety of reaction conditions and readily revert back to the hydroxamic acid by treatment with Nafion-H in 2-propanol. The method is applicable to primary, secondary, tertiary, and aromatic hydroxamic acids, and the acidity of the protons adjacent to the dioxazole allows α-functionalization.
