Isocyanid‐ und Heteroallen‐verbrückte Metallkomplexe, IX. Di‐ und Trieisenkomplexe mit funktionellen Isocyanidbrücken

Isocyanide‐ and Heteroallene‐Bridged Metal Complexes, IX [1,2] . – Di‐ and Triiron Complexes with Functional Bridging Isocyanides The reactions of ten mainly functional isocyanide dichlorides RN = CCl 2 with Na[FeCp(CO) 2 ] in tetrahydrofuran give mono‐isocyanide derivatives [Fe 2 (Cp) 2 (CO) 3 CNR] ( 1 a–g ) of [Fe‐Cp(CO) 2 ] 2 in which the isocyanide occupies a bridging position. In three cases also minor amounts of diisocyanide complexes [FeCp(μ‐CNR)CO] 2 ( 2c, 2e, 8 ) have been isolated. The chlorocarbonyl‐substituted aryl isocyanide dichlorides and pentafluorophenyl isocyanide dichloride in addition suffer (CO)Cl/ and F/ metal exchange, respectively, with formation of μ 3 ‐isocyanide‐bridged triiron complexes ( 4 a–c, 7 ) via the intermediates 5 and 6, 7 has been studied by X‐ray analysis.