A proton spin-lattice relaxation pathway analysis of conformational preferences of aryl and enol ethers in some cinchona and morphine alkaloids

Abstract

The spin-lattice relaxation rates of protons adjacent to hydroxyl and methoxy groups in aryl and enol ethers are dependent on the orientation of the alkyl group. This property has been employed to identify preferred conformations of these groups in some cinchona and morphine group alkaloids.

A Homonuclear Equivalent of the INEPT Experiment. Simplification of Crowded Proton Spectra and Measurement of Unresolved Couplings

“…We demonstrate this effect with the 400 MHz proton spectrum of strychnine (15)(16)(17)(18). Protons 15a and 15b have a 14.5 Hz geminal coupling constant.…”

Iron (III) Chloride Catalyzed Claisen Rearrangement Reaction of Allyloxyarenes under Microwave Conditions

“…Hence, the ortho-rearranged product would remain as the sole product. The spin-lattice relaxation time (T 1 ) can be used to determine the conformational preference of the molecules [12]. Therefore, the 1 H-NMR relaxation time study was conducted to investigate the molecular motion of the proton.…”