Yong Deng

Synthesis of 5-Carbonyl-1,3-dihydro- 1,3-dioxo-2H-isoindole-2-propanoic Acid Integrin Antagonists

Abstract The 5-carboxy-1,3-dihydro-1,3-dioxo-2H-isoindole-2-propanoic acid benzyl ester (I), obtained from condensation of 1,3-dihydro-1,3-dioxo-5-isobenzofurancarboxylic acid with β-alanine benzyl ester p-toluenesulfonate, reacted with an appropriate amine (II) to afford the corresponding amide (IIIa–e), which then hydrogenolyzed by 5% palladium-on-carbon to give target compounds (IVa–e).

Reactions of Disulfides with Silyl Phosphites to Generate Thiophosphates Under Neat Conditions

An efficient procedure for the synthesis of thiophosphates is described. Without using any metallic catalyst or base, the direct sulfur-phosphorus coupling reaction of disulfides and dialkyl trimethylsilyl phosphite (DTSP) was carried out under solvent-free reaction conditions in moderate to excellent yields with good functional group compatibility. The reaction conditions represent an advance over established methods not only in omitting the need for expensive catalysts or solvents, but also in shortening the reaction time significantly.These transformations are easy to conduct and can be readily applied to gram-scale preparation.

Visible light photoredox catalyzed thiophosphate synthesis using methylene blue as a promoter

A novel efficient method for the synthesis of thiophosphate derivatives catalyzed by methylene blue with blue light irradiation under an air atmosphere is described. The thiophosphate products, which are found in many pharmaceuticals and pesticides, were obtained in moderate to good yields. Moreover, Stern–Volmer fluorescence quenching experiments were conducted on reaction partners, demonstrating that the transformation involves photoinduced electron transfer. A plausible mechanism is proposed.