Gaseous Nitrogen Dioxide for Sustainable Oxidative Deprotection of Trimethylsilyl Ethers

Abstract

In this study, trialkylsilyl ethers of indispensable protected alcohols are oxidatively deprotected in neat form with gaseous nitrogen dioxide (NO₂). Quantitative yields of aldehydes or ketones are obtained without the necessity of chromatography. The byproducts, nitrogen monoxide, anhydrous nitric acid, and hexamethyldisiloxane, can be quantitatively separated by evaporation and distillation in closed systems for recycling or further use. The direct new method supersedes the previous techniques that produce dangerous wastes and require chromatographic workup, while the atmospheric gas NO₂ and its gaseous reduction products are easily kept in closed systems until further use.

GRAPHICAL ABSTRACT

Keywords:

• Catalyzed elimination
• gaseous nitrogen dioxide
• organic nitrate
• oxidative deprotection
• solvent-free liquid–gas reaction
• solventless synthesis
• trimethylsilyl ether

Acknowledgments

The authors acknowledge the partial financial support from the Iran University of Science and Technology (IUST) for this work.