Microwave assisted synthesis of calix[4]arene-excimer-based chemosensors

ANYL 253

Maryna G. Gorbunova1, Gilbert M. Brown, browngm1@ornl.gov2, Reza Dabestani, dabestanir@ornl.gov1, and Peter V. Bonnesen2. (1) Oak Ridge National Laboratory, Oak Ridge, TN 37831-6119, (2) Chemical Sciences Division, Oak Ridge National Laboratory, P. O. Box 2008, Oak Ridge, TN 37831-6119
Rapid development of host-guest chemistry and supramolecular technology has lead scientists to design new fluorescent probes capable of selective recognition of metal ions. Calix[4]arenes with pyrene pendent groups have received increasing attention and became promising candidates for the sensing probes because they are in a pre-organized framework to easily accommodate metal cations or anions and exhibit a selective change in the fluorescence emission. Recently we have reported the synthesis of new pyrene-appended calix[4]arenes in the cone- and 1,3-alt- conformations. A significant disadvantage to the use of these compounds is the need for lengthy, multi-step synthetic procedures. Now we report the first microwave assisted synthesis of the above-mentioned compounds. This method allows reduced reaction times from 20 hours to 20 minutes. The fluorescence spectra of both cone and 1,3-alternate calix[4]arene free ligands as well as their metal ion complexes will be compared and contrasted.