Diazenide

The radical and the anion, R-N2 and R-N2, derived (formally) from a diazonium ion by addition of one and two electrons respectively, are named as diazenyl ( radical at the end is not necessary ) and diazenide (IUPAC, 1993). The radical derived formally from a diazoalkane by addition of a hydrogen atom (R=N-NH) is named diazanyl . In order to be consistent with the nomenclature of diazonium ions, the name of the parent compound should precede the words mentioned, e. g., benzenediazenyl for C6H5 - NJ (the term phenyldiazenyl radical is, however, used by Chemical Abstracts). 

Monomeric non-oxo molybdenum(V) complexes have been isolated with nitride (N3 ), imide (NR2-) and amide (NRR -) ligands, which may act as models for intermediates in the degradation of dinitrogen in nitrogenase. However, no molybdenum(V) compounds are yet known which correspond to the diazenide or hydrazide analogues of the molybdenum(IV) complexes described in Section 36.4.2.3. 

Although the peroxide ion, 02, and the acetylide ion, C2, have long been known, the diazenide ion (N2 ) has only recently been prepared. By comparison with the other diatomic species, predict the bond order, bond distance, and number of unpaired electrons for N2. (Reference G. Auffermann, Y. Prots, and R. Kniep, Angew. Chem., Int. Ed., 2001, 40, 547)... 

Strontium diazenide nitride SrN2 TFXA, MARI 181... 

G. Auffermann, Y. Prots, R. Kniep, S.F. Parker S.M. Bennington (2002). Chem. Phys. Chem., 3, 815-817. Inelastic neutron scattering spectroscopy of diazenides detection of the N=N stretch. 

The Bamford-Stevens synthesis is related to the Shapiro reaction (Shapiro and Heath, 1967 reviews Shapiro, 1976 Adlington and Barrett, 1983), in which a 4-toluenesulfonyl hydrazone of an aldehyde or a ketone is treated with at least two equivalents of a very strong base, usually, methyllithium (see Organic Syntheses examples of Chamberlin et al., 1983, and Shapiro et al., 1988). The Shapiro reaction leads to an olefin by a hydrogen shift. The mechanism has been proposed by Casanova and Waegell (1975) as given in (2-34). This mechanism involves a diazenide anion 2.81 as intermediate. 

In an earlier review (Zollinger, 1994, Chapt. 8) we explained that the dediazoniation of aromatic diazonium ions to aryl cations and dinitrogen, or to aryl radicals and dinitrogen in the presence of suitable electron donors, is based primarily on the high stability of N2. Analogous aliphatic diazonium ions show similar behavior, but the existence of diazenides (R —Nf) and diazoalkanes also opens the possibility of generating carbanions, e.g., in the Wolff-Kishner reduction and related reactions (see the classic book of Cram, 1965, and the monographs of Staley, 1985, and Buncel and Durst, 1980-1987), and carbenes (see Chapt. 8 of this book). 

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