McMurry coupling Subject

In the laboratory of T. Nakai, the asymmetric tandem Claisen-rearrangement-ene reaction sequence followed by a modified McMurry coupling was used to access (+)-9(11)-dehydroestrone methyl ether. The Claisen-ene product was subjected to ozonolysis and epimerization to the 8,14-anf/ configuration. The C-ring was constructed by treating the tricyclic diketo aldehyde with TiCl3-Zn(Ag) in DME to afford the desired final product in 56% yield. 

A one-pot synthesis of phenanthrenes from ortho-alkoxy a re ne aldehydes and ketones has been accomplished using TiCl3-Li-THF [103]. The 2,2 dialkoxystil-benes, resulting from a classical McMurry coupling [80], are subjected to a reductive dealkoxylation and under the reaction conditions applied [103] form the intramolecular CC coupling products in moderate overall yields (25-38%). 

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