ORGN 208 |
| Rigid macrocycles represent intriguing targets that find application in areas such as materials science. Work on hexa-m-phenylenes over the past several decades has been scarce. To the best of our knowledge, there have been few if any attempts to synthesize hexa-m-phenylenes bearing functionality more complex than methyl and methoxy substituents. Using a six-fold Suzuki coupling (with no need for high-dilution), we have achieved a one-step synthesis of several highly functionalized hexa-m-phenylenes from simple pre-formed coupling partners. These macrocycles possess six aryl/alkylethynyl substituents on the periphery, as well as three methoxy groups in the cavity. This six-fold coupling method failed in cases without internal methoxy groups, raising the interesting possibility of a template effect brought about by cesium ions in solution. However, using an oxidative coupling approach, we also succeeded in synthesizing a tetrakis-(p-alkoxyphenylethynyl)-hexa-m-phenylene sans methoxy groups. |
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Total Synthesis, Materials, Devices and Switches, Molecular Recognition and Self-Assembly, Biologically-Related Molecules and Processes
8:00 PM-10:00 PM, Sunday, August 19, 2007 BCEC -- Exhibit Hall - B2, Poster
Division of Organic Chemistry |