The use of the selective population inversion technique in the assignment of carbon-13 n.m.r. resonances in 3,6-epoxy-pentacyclo[6.2.1.02,7.04,10.05,9]undecane

Different applications of the selective population inversion technique in an n.m.r. study of 3,6-epoxypentacyclo-[6.2.1.0^2,7.0^4,10.0^5,9] undecane have been demonstrated. The intensity gain accompanying heteronuclear ¹³C—{¹H} experiments allowed the detection of fine structure due to long range C? H couplings otherwise hidden in normal proton coupled ¹³C spectra. Definite assignments of two very similar, directly bonded, C? H couplings within a methylene group have been made.