Continuous Flow Synthesis of tert-Butyl Nitrite and Its Applications as Nitrating Agent

Abstract

Herein we report a flow chemistry method for the synthesis of tert-butyl nitrite. The flow process provided 95% yield in a very short residence time of 1 min corresponding to a space time yield of 13 g/h/mL. In addition, we used tert-butyl nitrite for metal-free stereoselective nitration of alkenes. The reported process had a higher batch cycle time of 12 to 24 h, limiting its application for commercial production. We developed a continuous-flow nitration process using a fixed bed column reactor. In the process, we provided the continuous air purging to ensure adequate supply of oxygen in the reaction. This has helped us to reduce the reaction time from 12 h in batch to 3 min in flow. The optimized nitration process conditions were applied on a series of styrene and acrylate derivatives. The methodology has potential for industrial-scale production of tert-butyl nitrite and its use as a nitrating agent.