Rational design, synthesis of reaction-based dual-channel cyanide sensor in aqueous solution.

A new dual-channel sensor for the detection of cyanide was developed based on the conjugated of naphthalene and malononitrile. Upon the addition of CN(-), the sensor displayed very large blue-shift in both fluorescence (80nm) and absorption (120nm) spectra. The sensor of cyanide was performed via the nucleophilic attack of cyanide anion to vinylic groups of the sensor with a 1:1 binding stoichiometry and the color changed of the sensor is mainly due to the intramolecular charge transfer process improvement. The intramolecular charge transfer progress was blocked with color changed and fluorescence blue-shift. The mechanism of sensor reaction with CN(-) ion was studied using (1)H NMR and mass spectrometry.

Solid-state Reaction of Azolium Hydrohalogen Salts with Silver Dicyanamide--Unexpected Formation of Cyanoguanidine-azoles, Reaction Mechanism and Their Hypergolic Properties.

Cyanoguanidines as well as azoles are important bioactive groups, which play an important role in the medical application; meanwhile, the high nitrogen content makes them excellent backbones for energetic materials. A Novel and simple method that combined these two fragments into one molecular compound was developed through the transformation of dicyanamide ionic salts. In return, compounds 4-11 were synthesized, and fully characterized by IR, MS, NMR and elemental analysis. Meanwhile, the structures of compounds 4, 8 and 11 were confirmed by X-ray crystal diffraction. Detailed reaction mechanisms were studied through accurate calculations on the reaction energy profiles of the azolium cations and DCA anion, which revealed the essence of the transformation proceeding. Meanwhile, compound 8 exhibits excellent hypergolic property, which could be potentially novel molecular hypergolic fuel.

Energetic salts based on an oxygen-containing cation: 2,4-diamino-1,3,5-triazine-6-one.

A family of energetic salts with high thermal stability and low impact sensitivity based on an oxygen-containing cation, 2,4-diamino-1,3,5-triazine-6-one, were synthesized and fully characterized by IR and multinuclear ((1)H, (13)C) NMR spectroscopy, elemental analysis, and differential scanning calorimetry. Insights into their sensitivities towards impact, friction, and electrostatics were gained by submitting the materials to standard tests. The structures of 2,4-diamino-1,3,5-triazine-6-one nitrate, 2,4-diamino-1,3,5-triazine-6-one sulfate, 2,4-diamino-1,3,5-triazine-6-one perchlorate, 2,4-diamino-1,3,5-triazine-6-one 5-nitrotetrazolate were determined by single-crystal X-ray diffraction; their densities are 1.691, 1.776, 1.854, and 1.636 g cm(-3), respectively. Most of the salts decompose at temperatures over 180 °C; in particular, the salts 2,4-diamino-1,3,5-triazine-6-one nitrate and 2,4-diamino-1,3,5-triazine-6-one perchlorate, which decompose at 303.3 and 336.4 °C, respectively, are fairly stable. Furthermore, most of the salts exhibit excellent impact sensitivities (>40 J), friction sensitivities (>360 N), and are insensitive to electrostatics. The measured densities of these energetic salts range from 1.64 to 2.01 g cm(-3) . The detonation pressure values calculated for these salts range from 14.6 to 29.2 GPa, and the detonation velocities range from 6536 to 8275 m s(-1) ; these values make the salts potential candidates for thermally stable and insensitive energetic materials.