A series of ditungsten complexes, W2(CO)9[μ,ŋ1,ŋ3-C(OCH3)C(R1)=CHR2] (3), containing μ-ŋ,ŋ3-allylidene ligands have been prepared in moderate to excellent yields from Fischer-type α,β-unsaturated tungsten carbene complexes, (CO)5W[C(OCH3)C(R1)=:CHR2] (1) and (CO)5W•THF (2). These complexes (3) we're purified on silica gel at -20 to -30 °C followed by crystallization to produce, in most cases, dark red crystalline materials. All new compounds were characterized by elemental analyses and 1 H and 13C NMR spectroscopy. When W2(CO)9[ŋ1,ŋ3-C(OCH3)C=CH(CH2)2CH2] (3d) was treated with CO in C6D6 solution, it was cleanly converted to the cyclopentenyl Fischer-carbenecomplex (CO)5W[C(OCH3)(C=CH(CH2)2CH2] (1d) and W(CO)6. W2(CO)9[μ-ŋ1,ŋ3-C(OCH3)C=CH(CH2)5CH2] (3f), which contains a cyclooctene ring as part of the μ-ŋ1,ŋ3-allylidene ligand, was further characterized by variable-temperature 13C NMR spectroscopy and single-crystal X-ray diffraction methods. Complex 3f crystallizes in the monoclinic space group P21/c with (at -150 °C) a = 9.832 (4) Å, b = 10.424 (3) Å, c = 21.120 (6) Å, β = 93.37 (3)°, and Dcalcd = 2.37 g cm-3 for Z = 4. Least-squares refinement based on 3394 independent observed [Fo > 5σ(F0)] reflections led to a final conventional R value of 0.038.