[ C+D] Double Labeling with Calcium Carbide: Incorporation of Two Labels in One Step.

D-labeling is a valuable tool in advanced synthetic chemistry and pharmacy. However, D-incorporation significantly complicates the identification of products. In fact, D labels are invisible in H-NMR spectra and cause undesirable splitting in C-NMR spectra which decreases the detectable limits. At the same time, H-NMR spectra are not effective for precise identification due to low sensitivity and the absence of correlations with H atoms. Here, C-label was considered as an accompanying label for D-label in [ C+D] unit for identification of D-containing sites and to track D-labels. [ C+D]-doubly labeled vinyl derivatives and triazoles were synthesized using C-labeled calcium carbide as a source of C-label and deuterium oxide as a source of D-label. The reaction occurred in one-step manner accompanied with in situ doubly labeled acetylene formation. Non-labeled, mono-labeled and doubly labeled substrates were isolated in 25-80% yields.