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A modular and completely stereoselectiveapproach for the constructionof all-carbon tetrasubstituted alkenes is described. It is based onthe three-fold, sequential metal-catalyzed, cross-coupling functionalizationof simple enolphosphate dibromide templates with carbon nucleophiles,affording tetrasubstituted alkenes as single isomers. [ABSTRACT FROM AUTHOR]

A mercuration reaction of tetrapropoxycalix[4]arene immobilized in the cone conformation gave a mixture of two dimercurated products (meta,meta and meta,para) in approximately a 1:1 ratio. Both regioisomers represent inherently chiral compounds, which makes them very attractive for design of novel receptors. As demonstrated by Pd-catalyzed arylation, the different reactivity of HgCl functions in the meta,para-disubstituted isomer opens the door for regioselective introductions of two different functional groups to achieve a substitution pattern so far unknown in calixarene chemistry.