ISSN 1070-4272, Russian Journal of Applied Chemistry, 2007, Vol. 80, No. 10, pp. 1643!1646. C Pleiades Publishing, Ltd., 2007.
Original Russian Text C I.V. Bachurina, M.A. Ilyushin, I.V. Tselinskii, Yu.A. Gruzdev, 2007, published in Zhurnal Prikladnoi Khimii, 2007, Vol. 80,
No. 10, pp. 1613!1616.
AND INDUSTRIAL INORGANIC CHEMISTRY
High-Energy Complex Copper(II) Perchlorate
with 1, 5-Pentamethylenetetrasole as Ligand
I. V. Bachurina, M. A. Ilyushin, I. V. Tselinskii, and Yu. A. Gruzdev
St. Petersburg State Technological Institute, St. Petersburg, Russia
Received April 24, 2007
Abstract-Possibility of obtaining an energy-saturated metal complex, copper tetrakis[cyclopentamethylene-
tetrasol] perchlorate, was studied by reacting copper(II) perchlorate hexahydrate with cyclopentamethylene-
tetrazol. The composition and structure of the complex were confirmed by elemental analysis and UV,
H NMR, and ESR spectroscopies. The thermal decomposition of the metal complex synthesized was
analyzed and its explosive characteristics and combustion law, as well as the combustion law of a model
formulation of a composite solid propellant with addition of the complex, were determined.
Modern tendencies in the development of rocket
technology presume use of fuels with high energy-
related characteristics. The specific momentum of the
fuels is raised by introduction of energetic components
with high heat of combustion, e.g., aluminum. How-
ever, this gives rise to the problem of a strong pres-
sure dependence of the combustion velocity of fuels
of this kind .
This problem can be solved by introduction into
fuels of additives that intensify processes occurring in
the condensed phase (C-phase).
It is known from the literature that copper com-
plexes containing polynitrous compounds as a ligand
can be used as modifiers of composite solid propel-
lants (CSP) .
Modifiers based on complex copper perchlorates
are use because they not only make weaker the pres-
sure dependence of the combustion velocity of CSP,
but also make faster the total combustion velocity
of the fuels. In this case, the cation catalyzes the com-
bustion velocity on the molecular level [3, 4].
We studied as a potential modifier of the combus-
tion process of CSP the previously obtained complex
copper(II) tetrakis-(1,5-pentamethylenetetrazol) per-
chlorate [complex (1)]:
Previously, complex (1) has been prepared in
a solution of 2,2-dimethoxypropane in 96% yield .
Because of the high cost and deficiency of 2,2-
dimethoxypropane, a search was carried out for alter-
native solvents and, in particular, the possibility of
using water and isopropyl alcohol was analyzed.
1,5-Pentamethylenetetrazol (PMT) contains [pyr-
idine nitrogen atoms] and has a high dipole moment
(6.14 D). It exhibits both weak basic and weak acid
properties [6, 7]. In the spectrochemical series of
ligands, it occupies a place between water and am-
monia . In view of this circumstance, we can
assume that it will replace water in the inner sphere
of copper perchlorate hexahydrate, to form com-
pounds with a neutral form of the ligand. The com-
plex was synthesized by the following scheme:
O + 4PMT 6 [Cu(PMT)
With water used as a solvent, the product yield is
about 60%; with isopropyl alcohol (IPA), a minor
amount of ethyl acetate (25% relative to the IPA vol-
ume) is to be added to the reaction mass for precipitat-
ing the target product. The yield of the product is
IR spectra of the complexes synthesized contain
absorption bands of all the fragments: coordinated
pentamethylene and tetrazol rings, perchlorate anions.
Data furnished by
H NMR spectroscopy for a free
ligand and the copper complex are listed in Table 1.