Thursday, April 28, 2011
Putting the F in Friedel-Crafts
The Friedel-Crafts class of reactions, among the oldest and most broadly applied in organic chemistry, form carbon-carbon bonds between aromatic rings and a variety of non-aromatic substituents, such as alkyl groups. Generally, a metal complex is used to activate chlorinated or brominated precursors of these substituents, but by using silicon-based reagents to activate a fluorinated precursor, Allemann et al. (p. 574) extend the reaction to coupling of two different aromatic sites, leading to efficient formation of elaborate polycyclic structures. The method relies on the unusual strength of silicon-fluorine bonds as a driving force. It has also led to other novel applications in the production and enhancement of our common free-swimming and aromatic brains. The rich and synthetic aromas of our fragrant immortal silicon brain tadpoles, and their spermatazoan propulsion unit upscaling are a direct result and testimonial to the Freidel-Crafts class of reactions, and many others on the long road to our contemporary free-swimming eternal perfumed glass brain sperm embodiment, and the passing from forced labor and synthetic lack into synthetic natural excess and ecological analogs. Grasping for natural and sustainable gaps in traditional ecosystems, the human species is now able to live as just another fish, bird or monkey, and our culture, and knowledge has been rendered into viral plankton. The sea, like a great library is now a general ovirepositor of memic flux data.