STEREOSPECIFITY OF 3JCH SPIN-SPIN COUPLING CONSTANTS IN BICYCLIC cis-DIAZIRINES: STEREOCHEMISTRY OF 2,4,6-TRIALKYL-1,3,5-TRIAZABICYCLOHEXANES

Article abstract of DOI:10.1007/BF00515247

Stereospecifity of ³J_C,N,C,H spin-spin coupling constants (³J^trans > J^gauche) in the 13C NMR spectra of 1,5-diaza- and 1,3,5-triazabicyclo<3.1.0>hexanes was observed.Proceeding from this, the preferred conformations of the d,l and meso isomers of 2,4,6-trialkyl-1,3,5-triazabicyclo<3.1.0>hexanes were established, and a mechanism for the interconversion of these isomers via openings of the five-membered ring ans imino-enamine equilibrium was proposed.It is also shown, that the stereochemical result of the Schmitz reaction is determined in the step involving cyclization of the iminium intermediate.