Epoxyfarnesyl acetate, titanocene-catalyzed cyclization

Scheme 12 Titanocene-catalyzed cyclization of epoxyfarnesyl acetate [53]...

The MesSiCl/col couple has also proved to be a suitable regenerating agent for Cp2TiCl-catalyzed cascade cyclizations of epoxypolyprenes [53]. Thus, the catalytic cyclization of epoxyfarnesyl acetate (4) (Scheme 12), for example, provided substantially increased yields of alkene 5 (40% versus the 25% obtained by the stoichiometric version) whilst employing lower titanocene proportions and dilution levels by one and two orders of magnitude, respectively. 

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