Nitration pyridines

Thermal decomposition of ammonium nitrate can also be facilitated by adding organic compounds. Thus, ammonium nitrate mixed with cellulose begins to decompose at 100°C and decomposition becomes distinctly perceptible at 120°C. Also salts of some organic bases (e.g. pyridine nitrate) considerably lower the temperature of decomposition of ammonium nitrate. 

Ammonium nitrate prepared from ammonia obtained by the dry distillation of coal should not be used as component of any explosive material because of the ammonium thiocyanate and pyridine present in it (the latter as nitrate). When the ammonia liquor from dry distillation of coal was the sole source af ammonia and ammonium nitrate, decomposition of mixtures containing ammonium nitrate with TNT (amatols), was brought about at the melting point TNT reacted with ammonium thiocyanate or with pyridine nitrate and evolved gaseous products. Minute traces of these impurities were sufficient to cause abundant gas evolution to develop during the fusion, pouring, and cooling of amatol. 

Trobach Priming Mixture. Patented in 1890 in Ger, consisted of Ba picrate 70, K chlorate 15 and salts of pyridine nitrate 15%... 

Indole, like benzothiophene, reacts with electrophiles to give preferentially -substituted products. Bromination241-243 in dioxane or pyridine, nitration by ethyl nitrate,244 chlorination by sulfuryl chloride,245 iodination in aqueous solution,246, 247 Vilsmeier and Reimer-Tiemann formylations,248-261 diazo coupling,252 thio-cyanation,263 and nitrosation254 all give the 3-substituted indoles, practically free from other isomers. 

As has already been mentioned in Section II, pyridine A-oxide is much more susceptible to electrophilic attack than is pyridine. Nitration with fuming nitric acid in sulfuric acid at 90° or with potassium nitrate or nitric acid in fuming sulfuric acid at 100-130° gives up to 90% yields of 4-nitropyridine A-oxide together with a small amount of the 2-isomer (formation of 2-isomer reported by... 

Battegay and Brandt [181a] succeeded in nitrating anthracene to 9-nitro-anthracene with 70% yield by heating anthracene with pyridine nitrate and excess of pyridine to 125°C. Naphthalene was nitrated to a-nitronaphthalene (40% yield) at 130°C in presence of zinc chloride. 

As in benzene chemistry, electron-releasing amino groups facilitate electrophilic substitution, so that, for example, 2-aminopyridine undergoes 5-bromination in acetic acid even at room temperature this product can then be nitrated, at room temperature, forming 2-amino-5-bromo-3-nitropyridine. Bromina-tion of all three amino-pyridines is best achieved with iV-bromosuccinimide at room temperature, products being 2-amino-5-bromo-, 3-amino-2-bromo- and 4-amino-3-bromopyridines. Similarly, chlorination of 3-amino-pyridines affords 3-amino-2-chloro-pyridines. Nitration of amino-pyridines in acid solution is also relatively easy, with selective attack of 2- and 4-isomers at P-positions. A mechanistic study of dialkylamino-pyridines showed nitration to involve attack on the salts. ... 

Furo[3,4-d]pyridazine-1,4-diones synthesis, 4, 985 Furopyridazines, 4, 984 Furo[2,3-fe]pyridine, 3-amino-synthesis, 4, 977 Furo[2,3-fr]pyridine, 4-methyl-synthesis, 4, 976 Furo[2,3-fe]pyridine, 6-methyl-synthesis, 4, 976 Furo[2,3-b]pyridine, 5-nitro-synthesis, 4, 977 Furo[3,2-c]pyridine, 4-allyl-synthesis, 4, 982 Furopyridines H NMR, 4, 983 physical data, 4, 983 properties, 4, 982 synthesis, 4, 974-982 UV spectroscopy, 4, 983 Furo[fe]pyridines HMO data, 4, 975 Furo[2,3-fr]pyridines synthesis, 4, 974-977 7, 512 Furo[3,2-fe]pyridines 13C NMR, 4, 982 synthesis, 4, 648, 981 Furo[c]pyridines HMO data, 4, 976 Furo[2,3-c]pyridines synthesis, 4, 977 Furo[3,2-c]pyridines nitration, 4, 983 synthesis, 4, 978-981 Furo[3,4-c]pyridines synthesis, 4, 982 Furo[3,2-c]pyridin-3-ols synthesis, 4, 980 Furo[2,3-i>]pyridin-6-ones synthesis, 4, 976 Furo[3,4-c]pyridin-4-ones synthesis, 4, 982... 

The metal isotope technique has been used to assign the p(M—py) and /(MX) vibrations of Zn(py)2X2 and Ni(py)4X2. The former vibrations have been located in the 225-160 and 250-225 cm" regions, respectively, for the Zn(ll) and Ni(II) complexes. Figure 111-9 shows the infrared and Raman spectra of [ Zn(py)2CU) and its Zn analog. As expected from its C20 symmetry, two i (Zn—py) and two v ZtiC ) are metal-isotope sensitive. Far-infrared spectra of metal pyridine nitrate complexes, M(py)x(N03)y, have been reported. 

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