Synthesis of Trinitroaromatics Using Alternative Mixed Acid Nitration Conditions

Abstract

Conditions for the mild and efficient nitration of phloroglucinol (1,3,5-trihydroxybenzene), 5-methoxyresorcinol, 3,5-dimethoxyphenol, and 1,3,5-trimethoxybenzene have been developed. Yields of the trinitro derivatives are excellent (∼90%) for systems having one or more hydroxyl groups, and in the case of 1,3,5-trimethoxybenzene, the trinitro analog was obtained in 62% yield. The optimum nitration conditions utilize sulfuric acid (94–98%) and an inorganic nitrate salt.

Keywords:

• Dimethoxypicric acid
• methoxystyphnic acid
• nitration
• trimethoxy-trinitrobenzene
• trinitrophloroglucinol

ACKNOWLEDGMENTS

This research was supported by the Department of Defense: Strategic Environmental Research and Development Program (SERDP Project WP 1582) and performed under ATK Space Systems Contract W912HQ-07-C-0018. Max Patterson of ATK Space Systems is gratefully acknowledged for his support with the NMR spectrometer, and Kieth Nielsen of ATK Space Systems is gratefully acknowledged for performing the elemental analyses. Thanks to Wayne Edwards and Clint Nelson for technical assistance with this work.

Notes

^a 3 mol. equivalents based on starting aromatic unless noted otherwise.

^b 4 mol. equivalents based on TMB.

^c For TMB→4, ramp rates are ∼5 °C/min. Reactions quenched at indicated temperature.