Diazoalkanes in Low-Coordinate Iron Chemistry: Bimetallic Diazoalkyl and Alkylidene Complexes of Iron(II)

The addition of (trimethylsilyl)­diazomethane
and its conjugate base to iron β-diketiminate precursors gives
novel dinuclear complexes in which the bridges are either diazomethane
derivatives or an alkylidene. One product is an unusual bridging alkylidene
complex containing two three-coordinate iron­(II) centers. On the other
hand, syntheses using the deprotonated diazomethane give two bridging
diazomethyl species with binding modes that have not been observed
in iron complexes previously. In the presence of a coordinating tetrahydrofuran
solvent, a diiron­(II) compound with μ-N bridges rearranges to
a more stable isomer with μ-N,C bridges, a process that is accompanied
by a 1,3-shift of a silyl group.