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

✍ Scribed by Joseph Jagur-Grodzinski

• Publisher: John Wiley and Sons
• Year: 1982
• Tongue: English
• Weight: 174 KB
• Volume: 18
• Category: Article
• ISSN: 0749-1581
• DOI: 10.1002/mrc.1270180410

✦ Synopsis

Abstract

^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.