Carbon-phosphorus-nitrogen rings

Treatment of 6,6 -dibromo-2,2 -dipyridine with phenylphosphine via Pd-promoted crosscoupling conditions gave a series of linear oligomers with terminal bromides as well as the cyclic dimer 24, in which the bipyridine moieties are held in the cis configuration by means of the two phenylphosphine A-oxide bridges 05JOC9835 . 

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Suitable methods for linking a phosphorus—nitrogen bond to the aziridine ring are the aminolysis of halogenated phosphorus compounds (2,280—282), the transamination of phosphoramines with excess aziridine (283), the reaction with phosphites (284) and phosphoramidites (285) which have a free OH group, or the reaction of phosphines with aziridines and carbon tetrachloride (286). 

Many of these ring systems are actually known see Phosphorus-Nitrogen Compounds). The phosphorusnitrogen analog of cyclobutadiene deserves a special citation, because unlike its organic (carbon) analog it can be isolated as stable compound. 

The triazine herbicides, atrazine and simazine, should be mentioned here because they also respond on the nitrogen-phosphorus detector. These herbicides contain the triazine ring, which is a six-member, conjugated ring containing alternating carbon and nitrogen atoms. 

Bertrand G, Bourissou D (2002) Diphosphorus-Containing Unsaturated Three-Menbered Rings Comparison of Carbon, Nitrogen, and Phosphorus Chemistry. 220 1 -25 Betzemeier B, Knochel P (1999) Perfluorinated Solvents - a Novel Reaction Medium in Organic Chemistry. 206 61 - 78... 

Diphosphorus Containing Unsaturated Three-Membered Rings Comparison of Carbon, Nitrogen and Phosphorus Chemistry... 

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