CATIONIC MICELLAR CATALYSIS OF THE AQUEOUS ALKALINE HYDROLYSES OF 1,3,5-TRIAZA-1,3,5-TRINITROCYCLOHEXANE AND 1,3,5,7-TETRAAZA-1,3,5,7-TETRANITROCYCLOOCTANE

The kinetics for the aqueous alkaline hydrolyses of 1, 3, 5-triaza-1, 3, 5-trinitrocyclohexane (RDX) and 1, 3, 5, 7-tetraaza-1, 3, 5, 7-tetranitrocyclooctane (HMX) in the presence of cationic micelles of ethylhexadecyldimethylammonium bromide (EHDMABr) have been investigated using an LC mode of analysis. Both hydrolyses showed excellent second-order rate constants. Activation parameters were determined for the HMX hydrolysis using the Eyring equation. RDX hydrolysis showed a maximum rate enhancement of 100-fold (at 1 X 10-2 M EHDMABr), while the HMX hydrolysis had a maximum relative rate increase of 27-fold (at 1 X 10-2 M EHDMABr). Conformations of HMX and RDX in the ground state and transition state are used in an attempt to explain the observed rate differences between the RDX and HMX hydrolyses. © 1979, American Chemical Society. All rights reserved.