Nitrogen chemical reactivity

Since the electrophilic reagent attacks the multiply-bonded nitrogen atom, as shown for (68) and (69), the orientation of the reaction product is related to the tautomeric structure of the starting material. However, any conclusion regarding tautomeric equilibria from chemical reactivity can be misleading since a minor component can react preferentially and then be continually replenished by isomerization of the major component. 

Chemical Reactivity - Reactivity with Water No reaction Reactivity with Common Materials Can catch fire when in contact with porous materials such as wood, asbestos, cloth, soil, or rusty metals Stability During Transport Stable at ordinary temperatures, however when heated this material can decompose to nitrogen and ammonia gases. The decomposition is not generally hazardous unless it occurs in confined spaces Neutralizing Agents for Acids and Caustics Flush with water and neutralize the resulting solution with calcium hypochlorite Polymerization Not pertinent Inhibitor of Polymerization Not pertinent. 

Mesomerism involving polarized and nonpolarized contributing enamine forms influences the enamine s spectral properties and chemical reactivity. For mesomerism to be present, a planar arrangement is required for the three atoms of enamine grouping and the five atoms immediately bound to this system. If this condition is not fulfilled, full interaction of the tt electrons of the double bond with the free electron pair on the nitrogen atom is impossible. Enamines in which mesomerism is inhibited do not show the properties characteristic of enamines, and only the mutual electrostatic interaction of the double bond and lone electron pair of the nitrogen atom can be observed. Such steric hindrance of mesomerism occurs mainly in polycyclic systems. 

The lactam-lactim tautomerism of hydroxyquinazolines is reflected in their chemical reactivity. Thus they are chlorinated to 4-chloro-quinazolines (see Section VI,A), and both 0- and A-methylation have been observed. When a substituent is already present on a nitrogen atom, as in 3-methyl-4(3i7)quinazolinone, chlorination gives 4-chloroquinazoline with loss of the methyl group (see la). 2-... 

Properties of deposits These are usually adherent and coherent. A/, is pure provided that all adverse chemically reactive gases are removed prior to sputtering nitrogen, for example, can form a nitride with copper, and oxygen can form oxides with most metals. 

Because the breadth of chemical behavior can be bewildering in its complexity, chemists search for general ways to organize chemical reactivity patterns. Two familiar patterns are Br< )nsted acid-base (proton transfer) and oxidation-reduction (electron transfer) reactions. A related pattern of reactivity can be viewed as the donation of a pair of electrons to form a new bond. One example is the reaction between gaseous ammonia and trimethyl boron, in which the ammonia molecule uses its nonbonding pair of electrons to form a bond between nitrogen and boron ... 

Dewar185-187 reported the first six-membered aromatic rings containing boron, oxygen, and nitrogen heteroatoms, and later Gronowitz188 prepared similar systems annelated with thiophene. The chemical reactivity and NMR data indicate electronic delocalization. 

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