Mild, General, and Regioselective Synthesis of 2-Aminopyridines from Pyridine N-Oxides via N-(2-Pyridyl)pyridinium Salts

A synthesis of 2-aminopyridines from pyridine N-oxides via their corresponding N-(2-pyridyl)pyridinium salts has been demonstrated and investigated. The reaction sequence features a highly regioselective conversion of the N-oxide into its pyridinium salt followed by hydrolytic decomposition of the pyridinium moiety to furnish the 2-aminopyridine product. The method is compatible with a wide range of functional groups, is scalable, and features inexpensive reagents. 15N-labeling results gave products consistent with a Zincke reaction mechanism.

One-Step Synthesis of Indolizino[3,4,5-ab]isoindoles by Manganese(I)-Catalyzed C–H Activation: Structural Studies and Photophysical Properties

Herein, a regioselective synthesis of indolizino[3,4,5-ab]isoindoles (INIs), a valuable class of heterocycles with interesting luminescence properties, is described using manganese(I)-catalyzed C−H activation. The reported transformation proceeds in a one-step procedure...

Visible-light-mediated Regioselective Synthesis of Novel Thiazolo[3,2-b][1,2,4]triazoles: Advantageous Synthetic Application of Aqueous Conditions

From a green chemistry perspective, sustainable irradiations as the power source and water as solvent have certainly grabbed the attention of chemists in recent times as these efforts reduce hazardous...

Triptycene Derivatives: From Their Synthesis to Their Unique Properties

Since the first preparation of triptycene, great progress has been made with respect to its synthesis and the understanding of its properties. Interest in triptycene-based systems is intense; in recent years, advances in the synthetic methodology and properties of new triptycenes have been reported by researchers from various fields of science. Here, an account of these new developments is given and placed in reference to earlier pivotal works that underpin the field. First, we discuss new approaches to the synthesis of new triptycenes. Progress in the regioselective synthesis of sterically demanding systems is discussed. The application of triptycenes in catalysis is also presented. Next, progress in the understanding of the relations between triptycene structures and their properties is discussed. The unique properties of triptycenes in the liquid and solid states are elaborated. Unique interactions, which involve triptycene molecular scaffolds, are presented. Molecular interactions within a triptycene unit, as well as between triptycenes or triptycenes and other molecules, are also evaluated. In particular, the summary of the synthesis and useful features will be helpful to researchers who are using triptycenes as building blocks in the chemical and materials sciences.