Iron isocyanides

The same reaction sequence was monitored by uv-visible spectroscopy and despite the lack of optical data for the zerovalent binary iron-isocyanide complexes, comparison with the spectrum for FeCCO) (18) reveals a close similarity. After the photolysis the original spectrum [an intense absorption at 232 nm with two shoulders at 297 and 340 nm] had decayed to be replaced by a new spectrum consisting of two bands at 220 and 382 nm. 

In this contribution we describe facile, high-yield syntheses of the series of zerovalent iron isocyanide complexes Fe(CO)5 (CNC6H3Me2-l,3)n ( n = 1-5). The starting material is iron pentacarbonyl, and cobalt(II) chloride is used as a catalyst to achieve the stepwise replacement of carbonyl groups by 2-isocyano-l,3-dimethylbenzene.4,9... 

It has been known from the 1970s that an iron complex can cleave the C-H bond of an arene [57, 58]. However, the exploitation of this reactivity for the development of a catalytic reaction has been largely neglected to date. An early attempt was described in 1987 [59], when Jones reported that an iron-isocyanide complex can insert the isocyanide group into the C-H bond of benzene upon irradiatirHi with light, and in the presence of added isonitrile and high dilution, the reaction was catalytic in iron, albeit the turnover was low (Eq. 23). 

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