Determination of the absolute configuration of a novel tetrasubstituted isoindolinone by vibrational circular dichroism

An effective method for the determination of the enantio-purity of L-α-glycerophosphocholine (L-α-GPC)

Herein we describe for the first time a practical analytical method for determining the enantio-purity of L-α-glycerophosphocholine (L-α-GPC) by chiral derivatization. The use of a suitable chiral boronic acid allowed the formation of a mixture of two diastereomeric boronate esters whose ratio, carefully analyzed by ¹HNMR spectroscopy, reflects L-α-GPC enantiomeric excesses. The determination of the enantiopurity of L-α-GPC furnishes convincing correlations with its manufacturing process.

5-Annulation of Ketoimines: TFA-Catalyzed Construction of Isoindolinone-3-carboxylates and Development of Photophysical Properties

Herein we have demonstrated the first report on 5-annulation of ketoimines to valuable isoindolinone-3-carboxylates. Instead of commonly used aldimine substrates, relatively less reactive ketoimines are employed for developing a TFA catalyzed organoreductive cyclization to furnish a variety of isoindolinones in excellent yield and reaction rate under mild reaction conditions. This is a metal-free event, which proceeds through a one pot ketoimine formation, hydride transfer from an organic reductant 2-(naphthalen-2-yl)-2,3-dihydrobenzo[ d]thiazole, and followed by five member cyclization sequences through TFA-activation of imine and ester groups. Studies on ESI-MS kinetics, leaving group aptitude, and control experiments led us to propose the mechanistic pathway of the new ketoimine-lactamization reaction. We have shown the synthetic utility of the emerging synthons through easy transformation of isoindolinones to different synthetic analogues. We investigated photophysical properties of the small molecules for their futuristic application as a pharmaceutical and materials, and the heterocycles displayed brilliant fluorescence activity.