Nmr Experiments on Ketals XIII [1]. Pmr Features and Relative Sign of Coupling Constants of 4‐Phenyl‐6‐Methyl‐1,3‐Dioxane

Abstract

Abstract In accordance with expectation, it is found that 2 J 5 is of opposite sign to the vicinal coupling constants 3 J 4,5 and 3 J 6,5 in trans ‐4‐phenyl‐6‐methyl‐l,3‐dioxane From the coupling values it is found that the conformational energy term for 4‐phenyl is roughly the same as that for a methyl group. Some previously mentioned [5, 6] long range couplings through four and five bonds are also found in this substance.