Solvent-free visible-light-mediated α-phosphorylation and Csp3-H activation of tertiary and secondary amines at room temperature in the presence of cadmium sulfide nanophotocatalyst

Abstract

Recently, the synthesis of organic compounds via Csp³-H activation is an important target for organic and medicinal chemists. On the other hand, visible-light-mediated organic synthesis is an attractive method, which is dependent on the capability of the reagent or photocatalyst to take up solar energy. Thus, the discovery and development of novel, Milde, simple, and effective manners using visible-light-induced photocatalysts have gained great interest in synthetic organic chemistry. Herein, cadmium sulfide (CdS) nanophotocatalyst has been successfully used for the reaction of tertiary and secondary amines with trialkyl phosphites or dialkyl phosphonates for the synthesis of dialkyl ((alkyl(aryl)amino)alkyl)phosphonate, dialkyl (2-benzyl-1,2,3,4-tetrahydroisoquinolin-1-yl)phosphonate, and dialkyl ((3,4-dihydroquinolin-1(2H)-yl)(aryl)methyl)phosphonate derivatives. Using this novel procedure, all desirable products were prepared in good yields and relatively short reaction times under solvent-free conditions at room temperature (more benignant conditions) with the usage of visible-light irradiation as an easily available, inexpensive, safe, and renewable energy source.

Keywords: CdS; Nanophotocatalyst; Solvent free; Visible light; α-Phosphorylation.