Diazomethane is both isomeric and isoelectronic with the more stable cyanamide, but they cannot interconvert.
Many substituted derivatives of diazomethane have been prepared:
*The very stable (CF)CN (2-diazo-1,1,1,3,3,3-hexafluoropropane; b.p. 12–13 °C),
*PhCN (diazodiphenylmethane; m.p. 29–30 °C).
*(CH)SiCHN (trimethylsilyldiazomethane), which is commercially available as a solution and is as effective as CHN for methylation.
*PhC(H)N, a red liquid b.p.< 25 °C at 0.1 mm Hg.