Ira A. Weinstock

HOMOGENEOUS CATALYSIS : ON THE TRAIL OF DIOXYGEN ACTIVATION

An ideal homogeneous catalyst for dioxygen (O2) oxidations would be selective, useful for tackling a variety of substrates and chemical structures, reasonably fast, and stable. Considerable progress towards this ideal is realized in a new catalyst containing two sterically protected ruthenium atoms, which can facilitate direct O2 activation and substrate oxidation without generating nonselective radicals.

Homogeneous Catalyzed Selective Oxidations Based on O2 or H2O2. New Systems and Fundamental Studies

We present here results that impact our fundamental knowledge regarding metal catalyzed O2 based oxidations and systems that address the mechanism of the Ishii/Venturello H2O2 based catalytic epoxidation chemistry. Our efforts continue to focus on fundamental energetic and mechanistic issues that define and indeed limit further development in the burgeoning area of selective catalytic oxidation. One particular application of a selective O2 based oxidation applied to an issue of practical and growing importance, the selective bleaching of wood pulp for paper manufacture, is a collaborative venture between our laboratories at Emory University and those of Dr. Weinstock and collaborators at the U.S. Department of Agriculture Forest Products Laboratory.

Synthesis, X-ray structure, and hydrolytic chemistry of the highly potent antiviral polyniobotungstate A-α-[Si2Nb6W18O77]8–

Potently antiviral polyniobotungstates have been structurally characterized; the dimer A-α-[Si2Nb6W18O77]8– cleaves cleanly to the monomer A-α-[SiNb3W9O40]7– within 1 min in aqueous solution buffered at physiological (neutral) pH establishing that the monomer and not the dimer is pharmacologically relevant.