The syntheses of a series of CpW (CO) 2 (π-γ-lactonyl) complexes bearing a tethered aldehyde are described. These π-allyl complexes are prepared as either syn-or anti- stereoisomers. Treatment of these dicarbonyl complexes with NOBF4 and NaI in CH3CN effects an intramolecular allylation of the tethered aldehyde, yielding bicyclic α-methylene butyrolactones comprising a homoallylic alcohol. Both syn-and anti-isomers of tungsten-π- ...
