Synthesis and ¹³C NMR Spectroscopy of ¹³C-Labeled α,ω-Diphenylpolyynes

Dedicated to Dr. Tom Nakashima for a lifelong commitment to NMR spectroscopy

Abstract

The synthesis of three ¹³C-labeled α,ω-diphenylpolyynes is described. The known positions of the labeled carbon atoms allow assignment of the resonances in the ¹³C NMR spectra and identification of trends in the chemical shifts.

Key words

alkynes - carbenes - ¹³C labeling - polyynes - Fritsch–Buttenberg–Wiechell rearrangement

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