Nitrogen terminal

Determination of Nitrogen by FP-228 Organic Nitrogen Terminator, LECO Corp., St. Joseph, Mich., 1985. 

A combination of nitrogen-terminated SAMs with MEE-stabilised nanoparticles turned out to be the optimal combination for the selective and dense deposition of gold layers. Through this, we were able to demonstrate that a large-scale (10 mm ) electrode set-up could be deposited under very mild conditions. 

In principle, any metabolic process that terminates in the production of ammonia or carbon dioxide can be similarly quantified in a continuous, automatic, incubation-quenching technique. Already some progress has been made with creatinine, another nitrogenous terminal metabolite, using an ammonia gas electrode [376], while glutaminase activity (arising from isoenzymes present in rat tissues and tumours) may be similarly determined [378]. Urea and tyrosine can be assayed [367] by using the appropriate decarboxylase and a carbon dioxide gas electrode. 

Colloidal gold and fine copper powder also catalyze diazoalkane polymerizations. The reaction appears to proceed by formation of alkylidene or carbene species that are bound to the surfaces of metals. " The initiations are completed by additions of diazoalkanes to the bound carbenes followed by liberations of nitrogen. Termination may take place by chain transfer, perhaps to a monomer, or to the solvent. " ... 

Note 2. The allenic ether is extremely sensitive towards oxygen. All operations during the work-up must be carried out under nitrogen. After termination of the distillation nitrogen should be admitted to the distillation apparatus. Too strong heating during the distillation involves the risk of an explosion. 

The principal reactions of this class of compounds are summarized in Scheme 172. In most of these reactions the reactive nucleophilic center is the terminal NHj group, although the other exocyclic nitrogen may also be involved, as shown by acetylation, which yields 284 and 285. However, the structure of compound 281 is not the one proposed in a recent report (1582) that attributes the attack to the other exocyclic nitrogen. The formation of osazones (287) from sugars, 2-hydrazinothiazoles, and hydrazine has been reported (525, 531). 

An electron pair on the terminal oxygen is shared with nitrogen to give a double bond... 

The polymerization of ethyleneimine (16,354—357) is started by a catalyticaHy active reagent (H or a Lewis acid), which converts the ethyleneimine into a highly electrophilic initiator molecule. The initiator then reacts with nitrogen nucleophiles, such as the ethyleneimine monomer and the subsequendy formed oligomers, to produce a branched polymer, which contains primary, secondary, and tertiary nitrogen atoms in random ratios. Termination takes place by intramolecular macrocycle formation. 

The effect of forming a more rigid structure in fluorescent dyes of the rhodamine series has been clearly demonstrated (18) with the remarkable dye designated Rhodamine 101 [41175A3-3] (19). This dye has its terminal nitrogen atoms each held in two rings and has a fluorescence quantum yield of virtually 100% independent of the temperature. 

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