Post on 15-Jan-2017
Deepak Chand,1 Lauren A. Mitchell,2 Damon A. Parrish,2 and Jean’ne M. Shreeve1* 1Department of Chemistry, University of Idaho, Moscow, Idaho, 83844-2343, United States
2Naval Research Laboratory, Code 6030, Washington, D.C. 20375-5001, United States.
Introduction
Synthesis of polyiodo compounds
Acknowledgment
The authors are grateful for the support of ONR (NOOO14-12-1-0536), and the
Defense Threat Reduction Agency (HDTRA1–11–1–0034 ).
References 1. Chand, D.; Shreeve, J. M; Chem. Commun. 2015, 51, 3438-3441.
2. Electrophilic iodination: A gateway to biocides and energetic materials; ( Manuscript
submitted to Angew. Chem. Int. Ed.)
3. Rahman, M. A; Shito, F.; Kitamura, T.; Synthesis. 2010, 27-29.
Versatile Polyiodopyrazoles: Synthesis and Biocidal Promise
Chemical and biological weapons possess huge destruction potential and pose considerable potential public threat. There is an estimate that deaths in millions could occur following the release of
only 100 kg of anthrax. As a result, interest in developing Agent Defeat Weapons (ADWs) has grown remarkably during the last few years. ADWs are airborne warheads which contain anti-bioagent
materials, such as iodine-rich compounds that form large amounts of elemental iodine, and hydroiodic acid (HI) as detonation products that have biocidal properties. In order to be a suitable ADW
feed, easily containable, non sublimable, and thermally stable sources of biocides are required. Polyiodopyrazoles can be good source of nonsublimable iodine. Up to nine iodine atoms were
introduced into a single molecule (13) in a one-pot reaction using trifluoroperacetic acid-mediated electrophilic iodination. The scope of this reaction was investigated extensively using diverse
pyrazole substrates. Detonation properties and detonation products are predicted by employing Cheetah 6.0. These compounds exhibit low detonation velocity and low detonation pressure. The
calculated (Cheetah 6.0) gas phase detonation products, were I2 and, in some cases, HI and I.
[M]+
[M]+
Table 1: Major detonation products shown by Cheetah 6.0 calculations [wt. % kg kg-1]
Figure 1: The sums of iodine-containing species in the detonation products of compounds 1,
2, 3, 4, and 5 (weight percent).
Thirteen polyiodopyrazoles including 3, 4, 5-triiodopyrazole were synthesized using
trifluoroperacetic acid mediated electrophilic iodination reaction.
Calculated detonation products and properties suggest that the compounds may be
effective bio-agent defeat agents.
These polyiodopyrazoles may have application not only as Agent Defeat Weapons but
also to other areas such as medicinal chemistry, materials science and synthetic
organic chemistry
Structure of 13
Crystal structure of 4
Crystal structure of 11
Comp N2 [g] I2 [g] HI [g] I [g] C [s]
1 6.22 52.1 22.87 10.34 8.00
2 6.09 81.9 - - 8.51
3 3.93 88.6 - - 6.34
4 22.2 49.6 - - 8.36
5 18.8 41.7 - - 5.07
Benzene based polyiodo pyrazoles
Ethylene bridged polyiodo pyrazoles
Introduction
Conclusions