Density functional calculation of (1)J(C-H) coupling constants in cyclohexane and diheterocyclohexanes. Repercussion of stereoelectronic effects on coupling constants

Ab initio calculations, within the framework of density functional theory, were carried out on cyclohexane, 1,3-dioxane, 1,3-dithiane, 1,3-oxathiane, and 1,3-diazane. The one-bond C-13-H-1 NMR coupling constants were estimate d according to the recently proposed theory by Malkin, Malkina, and Salahub . [Malkin, V. G.; Malkina, O. L.; Salahub, D. R. Chem. Phys. Lett. 1994, 22 1, 91]. No correlation between one-bond C-13-H-1 spin-spin coupling constan ts and the corresponding C-H bond distances was found. The direction of the Perlin effect, defined as the difference between the axial minus the equat orial one-bond C-H coupling constants, is correctly predicted by this metho dology for all cases with the exception of one methylene group in 1,3-oxath iane. Thus, in general, the methodology is capable of reproducing subtle pr operties that are driven by. stereoelectronic interactions.