Carbamylphosphonates and Related Compounds—Nuclear-Magnetic-Resonance and Infrared Spectra

Abstract
Proton magnetic resonance and infrared spectra were obtained for 44 carbamylphosphonates and related compounds, the common structural features being the grouping As with ordinary amides, slow rotation is observed around the carbonyl-to-nitrogen bond, but the chemical shift between nitrogen substituents is three to five times as great. Evidence is presented for long range coupling of phosphorus to protons in N-substituents. Correlations are observed between the carbonyl and phosphoryl stretching frequencies and substituents both on nitrogen and on phosphorus.