2‐Pyridylmetallocenes, Part VII. Synthesis and Reactivity of cycloaurated Pyridylmetallocenes. Spectroscopic and Crystallographic Characterization

Treatment of the 2‐pyridylferrocenes [CpFe(C5H3R{C5H4N})] (R= H, Me) with HAuCl4 or NaAuCl4 in aqueous acetonitrile yields the cycloaurated complexes [CpFe(C5H2R{C5H4N}AuCl2)] (R= H, 2a; Me, 2b). Reaction of 2a,b with phenylacetylene in the presence of CuI and NEt3 produces the monoalkynyl complexes [CpFe(C5H2R{C5H4N}AuI{CCPh})] (R= H, 3a; Me, 3b), while the reaction of 2a with NaCN/ LiCl yields.the bis‐cyanide [CpFe(C5H3{C5H4N}Au{CN}2)] 4a. The molecular structures of 2a, 3a, 3b and 4a were determined by X‐ray diffraction.