Carbon–nitrogen bond

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A carbon–nitrogen bond is a covalent bond between carbon and nitrogen and is one of the most abundant bonds in organic chemistry and biochemistry.[1]

Nitrogen has five

ammonium salts. Many nitrogen compounds can thus be potentially basic but its degree depends on the configuration: the nitrogen atom in amides is not basic due to delocalization of the lone pair into a double bond and in pyrrole
the lone pair is part of an aromatic sextet.

Similar to

pm for simple amines to 147.5 pm for C-N= compounds such as nitromethane to 135.2 pm for partial double bonds in pyridine to 115.8 pm for triple bonds as in nitriles.[2]

A CN bond is strongly polarized towards nitrogen (the

molecular dipole moments can be high: cyanamide 4.27 D, diazomethane 1.5 D, methyl azide 2.17, pyridine 2.19. For this reason many compounds containing CN bonds are water-soluble. N-philes are group of radical molecules which are specifically attracted to the C=N bonds.[3]

Carbon-nitrogen bond can be analyzed by X-ray photoelectron spectroscopy (XPS). Depending on the bonding states the peak positions differ in N1s XPS spectra.[4][5][6]

Nitrogen functional groups

Chemical class
Bond order Formula Structural Formula Example Avg. C–N bond length (Å)[7]
Amines 1 R2C-NH2 Primary amine methylamine
Methylamine
1.469 (neutral amine)
1.499 (ammonium salt)
Aziridines 1 CH2NHCH2 Aziridine
Mitomycin

1.472
Azides 1 R2C-N3 Azide Phenyl azide
Phenyl azide
1.38–1.48[8]
1.47 (methyl azide)[9]
1.432 (phenyl azide)[10]
Anilines 1 Ph-NH2 Aniline Ansidine
Anisidine
1.355 (sp2 N)
1.395 (sp3 N)
1.465 (ammonium salt)
Pyrroles 1 amide Porphyrin
Porphyrin
1.372
Amides 1.2 R-CO-NR2 amide Acetamide
Acetamide
1.325 (primary)
1.334 (secondary)
1.346 (tertiary)
Pyridines 1.5 pyr pyridine Nicotinamide
Nicotinamide
1.337
Imines 2 R2C=NR imine DBN
DBN
1.279 (C=N bond)
1.465 (C–N bond)
Nitriles 3 R-CN Nitrile Benzonitrile
Benzonitrile
1.136
Isonitriles
3 R-NC isonitrile
TOSMIC
1.154[11]

See also

References

  1. ^ Organic Chemistry John McMurry 2nd Ed.
  2. ^ CRC Handbook of Chemistry and Physics 65Th Ed.
  3. PMID 12430429
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  7. ^ F. H. Allen, O. Kennard, D. G. Watson, L. Brammer, A. G. Orpen. Tables of bond Lengths determined by X-Ray and Neutron Diffraction. Part 1. Bond Lengths in Organic Compounds. J. Chem. Soc. Perkin Trans. II 1987, S1-S19.
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