S. P. Teong, J. Lim, Y. Zhang, ChemSusChem 2017, 10, 3198.
Abstract:
Calcium carbide has been increasingly used as a sustainable, easy‐to‐handle, and low‐cost feedstock in organic synthesis. Currently, methodologies of using calcium carbide as “solid acetylene” in synthesis are strictly limited to activation and reaction with X−H (X=C, N, O, S) bonds. Herein, a mild and transition‐metal‐free protocol was developed for the vinylation of epoxides and aryl ether linkage (β‐O‐4 lignin model compound) with calcium carbide through C−O bond cleavage, forming valuable vinyl ether products. Calcium carbide plays a vital role in the C−O bond activation and cleavage, and in providing acetylide source for the formation of vinylated products. These exciting results may provide new methodologies for organic synthesis and new insights toward lignin‐ or biomassrelated degradation to useful products.