New aminating reagents forthe synthesis of 1,3,5-Triamino-2,4,6-Trinitrobenzene (TATB) and other insensitive energetic materials

We are investigating the amination of electrophilic aromatic systems through the use of Vicarious Nucleophilic Substitution (VNS) chemistry. This research has led to a new synthesis of 1,3,5-Triamino-2,4,6-trinitrobenzene (TATB) and 1,3-diamino-2,4,6-trinitrobenzene (DATB) which uses 2,4,6-trinitroaniline (picramide) or 1,3,5-trinitrobenzene as starting materials. We also describe the development of a new class of VNS aminating reagents based on quarternary hydrazinium halides. 1,1,1-Trimethylhydrazinium iodide (TMHI), available from the methylation of the surplus propellant uns-dimethylhydrazine (UDMH), was used in a new synthesis of TATB. The advantages, scope and limitations of the VNS approach to the synthesis of TATB and other amino-substituted nitroarenes are discussed

Recent advances in the chemical conversion of energetic materials to higher value products

The objective of this program is to develop novel R3 (Resource Recovery and Recycling) alternatives to the open burning/open denotation (OB/OD) of surplus energetic materials higher value products potentially provides environmentally sound and cost- effective alternatives to OB/OD. Our recent studies on the conversion of surplus energetic materials (high explosives, propellants). The use of energetic materials as chemical feedstocks for higher value products potentially provides environmentally sound and cost-effective alternatives to OB/OD. Our recent studies on the conversion of surplus energetic materials to higher value products will be described

A new synthesis of TATB using inexpensive starting materials and mild reaction conditions

TATB is currently manufactured in US by nitration of the expensive TCB to give 2,4,6-trichloro-1,3,5-trinitrobenzene which is then aminated to yield TATB. Elevated temperatures (150 C) are required for both reactions. There is a need for a more economical synthesis of TATB that also addresses current environmental issues. We have recently found that 1,1,1-trimethylhydrazinium iodide (TMHI) allows the amination of nitroarenes at ambient temperature via Vicarious Nucleophilic Substitution of hydrogen. TMHI reacts with picramide in presence of strong base (NaOMe or t-BuOK) to give TATB in over 95% yield. TMHI and picramide can be obtained from either inexpensive starting materials or surplus energetic materials from demilitarization activities, such as the 30,000 metric tons of UDMH (surplus rocket propellant) from the former Soviet Union

A Versatile Synthesis of 1,3,5-Triamino-2,4,6-Trinitrobenzene (TATB)

A safe and versatile synthesis of high-purity 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) based on vicarious nucleophilic substitution (VNS) chemistry has now been achieved. The starting material can be selected from a variety of inexpensive nitroarenes obtained from commercial suppliers (4-nitroaniline, picric acid) or U.S. stockpiles (ammonium picrate, TNT). The use of picric acid and ammonium picrate (Explosive D) is preferred as both compounds are directly converted to picramide in the presence of ammonium salts (diammonium hydrogen phosphate, ammonium carbamate) in sulfolane at elevated temperature. The picramide resulting from this process is directly converted to TATB using an optimized VNS reaction employing inexpensive hydroxylamine as the nucleophilic aminating reagent. A crucial element in our synthesis is a novel and efficient purification of TATB

Overactive bladder – 18 years – Part II

ABSTRACT Traditionally, the treatment of overactive bladder syndrome has been based on the use of oral medications with the purpose of reestablishing the detrusor stability. The recent better understanding of the urothelial physiology fostered conceptual changes, and the oral anticholinergics – pillars of the overactive bladder pharmacotherapy – started to be not only recognized for their properties of inhibiting the detrusor contractile activity, but also their action on the bladder afference, and therefore, on the reduction of the symptoms that constitute the syndrome. Beta-adrenergic agonists, which were recently added to the list of drugs for the treatment of overactive bladder, still wait for a definitive positioning – as either a second-line therapy or an adjuvant to oral anticholinergics. Conservative treatment failure, whether due to unsatisfactory results or the presence of adverse side effects, define it as refractory overactive bladder. In this context, the intravesical injection of botulinum toxin type A emerged as an effective option for the existing gap between the primary measures and more complex procedures such as bladder augmentation. Sacral neuromodulation, described three decades ago, had its indication reinforced in this overactive bladder era. Likewise, the electric stimulation of the tibial nerve is now a minimally invasive alternative to treat those with refractory overactive bladder. The results of the systematic literature review on the oral pharmacological treatment and the treatment of refractory overactive bladder gave rise to this second part of the review article Overactive Bladder – 18 years, prepared during the 1st Latin-American Consultation on Overactive Bladder

New synthesis of TATB process development studies

We described a new synthesis of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) in 1996 at the 27th International Annual Conference of ICT. 1,1,1-trialkylhydrazinium salts are highly reactive reagents which aminate nitroaromatic compounds through vicarious nucleophilic substitution (VNS) of hydrogen. When applied to picramide, these reagents produce TATB in high yield. Traditionally, TATB has been manufactured in the USA by nitration of the relatively expensive and domestically unavailable 1,3,5-trichlorobenzene (TCB) to give 2,4,6-,trichloro- 1,3,5-trinitrobenzene (TCTNB) which is then aminated to yield TATB. Elevated temperatures (150{degrees}C) are required for both reactions. Our new VNS synthesis potentially affords an inexpensive and a more environmentally benign preparation of TATB. We describe in this report our progress in scaling up the synthesis of TATB from the laboratory to the pilot plant. We will discuss structure and control of impurities, changes in yield/quality with reaction conditions, choice of solvents, workup and product isolation, safety, and environmental considerations. Particle size characterizations as well as small-scale safety and performance testing will also be discussed

Conversion of the rocket propellant UDMH to a reagent useful in vicarious nucleophilic substitution reactions

The objective of our program is to develop novel, innovative solutions for the disposal of surplus energetic materials resulting from the demilitarization of conventional and nuclear munitions. In this report we describe the use of surplus propellant (UDMH) and explosives (TNT, Explosive D) as chemical precursors for higher value products. The conversion of UDMH to 1,1,1-trimethylhydrazinium iodide (TMHI) provides a new aminating reagent for use in Vicarious Nucleophilic Substitution (VNS) reactions. When TMHI is reacted with various nitroarenes the amino functionality is introduced in good to excellent yields. Thus, 2,4,6-trinitroaniline (picramide) reacts with TMHI to give 1,3,5-triamino-2,4,6-trinitroaniline (TATB) while 2,4,6-trinitrotoluene (TNT) reacts with TMHI to give 3,5-diamino-2,4,6-trinitrotoluene (DATNT). The advantages, scope and limitations of the VNS approach and the use of TMHI are discussed