X-ray and NMR structural investigations of (+/-) (u) N-(1-phenylethyl)-1-t-butylsulfinyl-1-propenyl-2-amine, C15H23NOS

Article abstract of DOI:10.1007/BF01158966

The structure of the title compound has been investigated in the solid state and in solution by X-ray and NMR-NOE methods, respectively.The crystals are monoclinic: P2₁/c, a = 9.828(1), b = 12.326(2), c = 13.976(2) Angstroem, β = 107.36(1) deg.The structure was solved by direct methods, and refined against 2495 unique reflections by a full-matrix, least-squares procedure giving R = 0.046.In the solid state the compound exists as the E isomer with unlike relative configurations on asymmetric atoms.In solution the compound is found as a mixture of a single enamine and two imine forms.The MM calculations suggest that of the two possible geometrical isomers of both diastereoisomers u and l of the enamine, the Z forms should be of lower energy.The total recognition of the homonuclear 1H NMR-NOE data interpreted in terms of their distance dependence in the two geometrical forms also favors the Z isomer in both diastereomers.