Nitrogen equivalent

Arylazo tosylates of type 248, which are readily obtained from aniline derivatives 249 in a two-step procedure (equation 162), can be alternatively used as starting materials. This electrophilic nitrogen equivalent 248 reacts with a broad range of functionalized Grignard reagents under mild conditions. Subsequent allylation of the addition products with allyl iodide, followed by reductive cleavage of the resulting hydrazine derivatives... 

The two positive oxidation states of P (+ 5 and + 3) are both more stable than their nitrogen equivalents, and phosphoric acid has no oxidant properties apart from those given by the hydrated protons produced from it in aqueous solution. A dilute solution of phosphoric acid will provide a sufficiently high concentration of hydrated protons to oxidize any metal to its most stable state, providing the reduction potentials for the metal ion/metal couple are negative. 

This type of reaction is very common in the nitrogen equivalent pyridine system (the ready formation of enamines and the ready availability of 1,3-electrophiles, such as acrolein and their equivalents). With the phosphorus system, the not so common enamine equivalent makes it a not so common synthetic approach. However, with proper substituents 1,3-dinucleophilic P-C(2) fragments have been reacted with 1,3-electrophiles, and have been used in the synthesis of As-phosphinolines <1996CHEC-II(5)639>. 

This is consistent with the rate law (Rate = A[M]2[K]ya) and in accord with the observation of Wooster and Ryan 95) that styrene is reduced in 50% yield to ethylbenzene by mixing equivalent quantities of sodium and styrene in liquid ammonia. That the reaction is rapid was indicated by the immediate discharge of the blue color and no formation of a red color characteristic of benzyl anions. Also nitrogen equivalent to one-NH2 per chain was found in the polymers. 

An amidine is the nitrogen equivalent of an amide—a C=NH group replaces the carbonyl. Amidines are much more basic than amides, the p faHs of amidines are larger than those of amides by about 13 so there is an enormous factor of 1013 in favour of amidines. In fact, they are among the strongest neutral bases. 

Next, re-aromatization of the benzene ring (by proton transfer from carbon to nitrogen) creates an aromatic amine that immediately attacks the other imine. This gives an aminal, the nitrogen equivalent of an acetal. 

You saw a carbonyl addition reaction forming a polymer right at the beginning of the chapter—the polymerization of formaldehyde. If an amine is added to formaldehyde, condensation to form imines and imine salts occurs readily. These intermediates are themselves electrophilic so we have the basis for ionic polymerization—electrophilic and nucleophilic molecules present in the same mixture. Reaction with a second molecule of amine gives an aminal, the nitrogen equivalent of an acetal. 

Production of fertilizer grade AN is concentrated mainly in Europe and North America. In 2001 U.S. production was 7.1 million tons, which was 18 percent lower than the peak production in 1998. U.S. plants were operating at 70 percent of nameplate capacity in 2001.240 International trade amounts to about 4 million tonnes (on a nitrogen equivalent basis) per year. Additional information can be found in Chapter 24, Fertilizers. ... 

Nitrene The univalent -N species, i.e. the nitrogen equivalent of a carbene. The simplest nitrene, NH, is also called nitrene, as well as imidogen, azene or imene. 

The imine and iminium functional groupings are, of course, the nitrogen equivalents of carbonyl and O-protonated carbonyl groups, and their reactivity is analogous. The Mannich reaction of pyrrole produces dialkylaminomethyl derivatives, the iminium electrophile being generated in situ from formaldehyde, dialkylamine and acetic acid. There are only a few examples of the reactions of imines themselves with pyrroles the condensation of 1-pyrroline with pyrrole as reactant and solvent is one such example. N-Tosyl-imines react with pyrrole with Cu(OTf>2 as catalyst. ... 

On the right-hand side of Fig. IS the atmospheric pathways of NH3 are plotted. Values of different terms are based on the references mentioned. In the figure, NH3 and NH4 burdens are also given. All numbers are expressed in nitrogen equivalents. In the total deposition value, a dry deposition of 10 x 10b t yr-1 is postulated. It should be noted that the accuracy of the values is not better than a factor of 2 or 3. It follows from these data that the residence time of NH3 in the atmosphere is around 5 days. 

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