Síntese de 2-(organosseleno)piridinas utilizando glicerols/H3PO2 como sistema redutor

Abstract

In this work was developed a new methodology to obtain 2-(organylselenyl)pyridynes 3 using glycerol and H3PO2 as reducing system under nitrogen atmosphere. At first, the reaction was heated at 90 °C to cleave the diorganyldiselenide 1 with H3PO2 to afford the organylselenol in situ, followed by the addition of the 2-chloropyridine at room temperature.The methodology allowed the synthesis of 14 products with good to excellent yield and short reaction times. Besides formation of products at room temperature, it was possible the reuse of glycerol/H3PO2 system for 5 cycles with similar efficiency and without the necessity to add new H3PO2 in each cycle. This new methodology is in agreement with the 5th, 6th and 7th principles of green chemistry that are respectively: Innocuous solvents and auxiliaries (glycerol); Energy efficient by design (reaction at room temperature) and Preferably renewable raw materials (glycerol).