title: Rapid acyl migration between pyrogallyl 1,2- and 1,3-dipivaloates.
abstract: Pyrogallol and its derivatives are biologically active compounds, and pyrogallol also forms the basis of an increasingly important tetrameric supramolecular scaffold. Pyrogallol[4]arenes are tetrameric macrocycles that form from 1,2,3-trihydroxybenzene and aldehydes under acidic conditions. Pyrogallol was treated with two equivalents of pivaloyl chloride to form pyrogallyl dipivaloate. A mixture of regioisomers was invariably obtained and a rapid equilibrium was observed between the 1,2- and 1,3-diesters in polar solvents. A pure sample of solid pyrogallyl 1,2-dipivaloate was isolated and its crystal structure was obtained. The pure compound was shown to rearrange to mixtures similar to those isolated initially.
authors.affiliation: Center for Nanoscience, University of Missouri, Saint Louis, MO 63121, USA.
authors.forename: Yaming
authors.initials: Y
authors.lastname: Shan
authors.forename: Jimmy
authors.initials: J
authors.lastname: Liu
authors.forename: Nigam P
authors.initials: NP
authors.lastname: Rath
authors.forename: George W
authors.initials: GW
authors.lastname: Gokel
mesh_terms: D007536:Isomerism; D010421:Pentanoic Acids / Q000138:chemical synthesis*; D011748:Pyrogallol / Q000737:chemistry*
chemical_list: D010421:Pentanoic Acids; D011748:Pyrogallol; C005566:pivalic acid