Proton NMR spectroscopy of asymmetric benzylamines. The long‐range effects of an asymmetric environment

1 H NMR Spectra of the asymmetric benzylamines N ‐benzyl‐ N ‐butyl‐2‐hydroxy‐1,3‐propandiamine, N ‐benzyl‐ N ‐(2‐ethylhexyl)‐2‐hydroxy‐1,3‐propandiamine, N ‐benzyl‐ N ‐butyl‐2,3‐epoxypropanamine and N ‐benzyl‐ N ‐(2‐ethylhexyl)‐2,3‐epoxypropanamine, were analysed. A pronounced non‐equivalance of the benzylic hydrogens is induced by asymmetric carbons in γ position with respect to the benzylic group. [Δδ=0.2–0.3 ppm; J (AB)∼13.5 Hz]. Two sets of AB patterns were observed when two asymmetric carbons were present in the same molecule. RS + SR Diastereomers can thus be distinguished from the RR + SS enantiomers.