STUDIES OF RDX AND RELATED COMPOUNDS: XI. THE CONVERSION OF PHX TO AcAn

Abstract

The formatioli of AcAli from PI-IX, nitric acid, and acetic anhydride has been investigated a t various teniperatures. The effects of added acetic acid and added salts have bee11 determined. While the reaction is first order with respect to PHX, it is of a n order 2.6 with respect to nitric acid. The reaction rate is significantly decreased by snlall co~icentrations of sodium nitrate. The reactjon is also characterized by a secondary salt effect and a low apparent actlvatlou energy of about 2 Itcal. mole-'. A mechanism has been suggested ill qualitative, and to sonle extent quantitative, agreement with the experimental data. I t is postulated that the conversion of P H X involves a rate-controlling ionic reaction between P H X and nitric acid, and that this is followed by a rapid acetylation of the acidic intermediate to AcAn.

Nitration

“…The formation of l,9-diacetoxypentamethylene-2,4,6,8-tetranitramine (AcAn) from 2-acetoxymethyl-4,6,8-trinitrocyclotetramethylenetetramine (PHX), nitric acid, and acetic anhydride was studied at various temperatures by Marcus and Winkler (18). The effects of added acetic acid and added salts wrere determined.…”