Iterative synthesis, oligomeric isoprenoids

Efficient and Selective Iterative and Convergent Synthesis of Oligomeric Isoprenoids Containing E- and/or Z-Trisubstituted 1,5-Diene Units... 

The iterative and convergent protocol using (E)- and/or (Z)-l,4-diiodo-2-methyl-1-butenes is efficient as well as regio- and stereoselective, requiring hardly any isomeric separation even in the synthesis of a decameric isoprenoid. It permits both iterative and convergent modes of construction of oligomeric isoprenoids in any desired ratio of the two modes of operation to best suit a given synthetic task. At any point of synthesis, either the E- or Z-trisubstituted Cs-alkene unit can be incorporated. This synthetic method promises to find many additional applications in the area of isoprenoid synthesis. 

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