Tetrahydrofurfuryl alcohol 20 is an important biomass-derived feedstock. Keiichi Tomishige of the University of Tsukuba reported (Chem. Commun. 2009, 2035. doi("10.1039/b822942b") DOI: 10.1039/b822942b) conditions for the selective cleavage of 20 to, respectively, 21 or 22.