Nuclear magnetic resonance studies: VII—¹³C and ¹⁵N n.m.r. of diazo compounds

The 13 C and 15 N n.m.r. results for a series of diazo compounds are reported. It is found that the diazo carbon is shielded by an extraordinary amount compared with normal sp 2 hybridized carbons. The 15 N chemical shifts reveal that the terminal nitrogen is deshielded relative to the central one. This is contrary to that expected from charge effects but support is found for this phenomenon in other systems. One‐bond 13 C 14 N coupling in diazomethane is also reported for the first time. INDO MO calculations of the charges and finite perturbation calculations of 13 C 14 N and CH couplings are compared with the experimental results.