Synthesis of fluorophenyl derivatives of iron, molybdenum and tungstenvia B(C6F5)3 and unusualcarbon–fluorine bond reactions

The reaction between B(C 6 F 5 ) 3 and [Fe(η-C 5 H 5 )(CO) 2 Me] gave the unexpected product [Fe{C 6 F 4 C(O)Me-2}(η-C 5 H 5 )(CO)] 1 which reacts with the donor molecules L = PMe 3 , PPh 3 or Bu t NC giving [Fe{C 6 F 4 C(O)Me-2}(η-C 5 H 5 )L].* Likewise [{Fe[C 6 F 4 C(O)Me-2](η-C 5 H 5 )} 2 (µ-dppe)]* was formed from 1 and Ph 2 P(CH 2 ) 2 PPh 2 (dppe). The formation of the compound where L = PMe 3 is shown to proceed via initial formation of [Fe{C 6 F 4 C(O)Me-2}(η-C 5 H 5 )(CO)(PMe 3 )]*. The reaction between B(C 6 F 5 ) 3 and [M(η-C 5 H 5 )(CO) 3 Me] (M = Mo or W) gave the compounds [M{C 6 F 4 C(O)Me-2}(η-C 5 H 5 )(CO) 2 ]. The compounds [M{C 6 F 3 X-5-C(O)Me-2}(η-C 5 H 5 )(CO) 2 ]* (M = Mo or W) where X = H were prepared from the compounds where X = F via unusual C–F bond-activation reactions. The compound [Fe{C 6 F 3 H-5-C(O)Me-2}(η-C 5 H 5 )(PMe 3 )] was prepared by photolysis of a mixture of [Fe{C 6 F 3 H-5-C(O)Me-2}(η-C 5 H 5 )(CO)] and PMe 3 . The asterisk indicates the crystal structure has been determined.