Reaction Species in the Aqueous Solution and Interfacial Synthesis of Zirconium Polyethers

Abstract
The following tentative identifications are made from the study of variations in pH and substituted hydroquinones in the synthesis of zirconium polyethers: active species for aqueous solution systems, CP2Zr2+ and RO η active species for interfacial systems, Cp2 ZrCl2 and R-OH with reaction occurring near the interface or in the organic phase. Yield increases as stirring rate increases throughout the stirring range of 13,000 to 24,500 rpm. Decent yields can also be obtained utilizing “inverse interfacial” systems where the Cp2 ZrCl2 is originally contained in water and the diol and added base in the organic layer. No product is found utilizing organic solution systems.