13C chemical shift assignments in cyclo-octene, cyclo-octanone, and cyclo-oct-2-enol from the spectra of monodeuterioisotopomers
Abstract
The 13C n.m.r. spectra of [3-2H1]- and [5-2H1]-cyclo-octenes indicate that the assigned shifts for C-4 and C-5 in the cycloalkene must be transposed. The spectra of [4-2H1]- and [5-2H1]-cyclo-octanones consolidate earlier evidence for the assignment of shifts in the case of the cyclic ketone. The 13C n.m.r. spectra of [1-2H1]-, [5-2H1]-, [6-2H1]-, [7-2H1]-, and [8-2H1]-cyclo-oct-2-enols afford unambiguous evidence for the origins of the signals in the spectrum of the unlabelled cyclo-octenol.