1203-33-4Relevant academic research and scientific papers
The effect of the nitrogen non-bonding electron pair on the NMR and X-ray in 1,3-diazaheterocycles
Garcías-Morales, Cesar,Martínez-Salas, Selene H.,Ariza-Castolo, Armando
, p. 3310 - 3315 (2012)
The effect of the nitrogen nonbonding electron pair on the 1JC,H values of 1,3-diazaheterocycles was analyzed and compared to 1,5-diazabiciclo[3.2.1]octanes, which have a restricted conformation. The 1JC,H values were measured by observing the 13C satellites in the 1H NMR spectra and then determining the 1H-coupled 13C NMR spectra. The 1JC,H values are 10 Hz larger when the α-hydrogen is synperiplanar rather than antiperiplanar to the nonbonding electron pair on the nitrogen, which serves as experimental evidence of the orbital n N→σC,Hap interactions. In addition, the homoanomeric effect from the interactions of the nitrogen lone pair with the antibonding orbital of the equatorial hydrogen, which was in the β position, was discussed (nN→σC(β),H eq).
