425380-68-3Relevant articles and documents
Acetylide-bridged organometallic oligomers via the photochemical metathesis of methyl-iron(II) complexes
Field, Leslie D.,Turnbull, Anthony J.,Turner, Peter
, p. 3692 - 3702 (2007/10/03)
The acetylido methyl iron(II) complexes, cis/trans-[Fe(dmpe)2(C≡R)(CH3)] (1) and trans-[Fe(depe)2(C≡CR)(CH3)] (2) (dmpe = 1,2-dimethylphoshinoethane; depe = 1,2-diethylphosphinoethane), were synthesized by transmetalation from the corresponding alkyl halide complexes. Acetylido methyl iron(II) complexes were also formed by transmetalation from the chloride complexes, trans-[Fe(dmpe)2(C≡CR)(Cl)] or trans-[Fe(depe)2(C≡CR)(Cl)]. The structure of trans-[Fe(dmpe)2(C≡CC6H5) (CH3)] (1a) was determined by single-crystal X-ray diffraction. The methyl acetylido iron complexes, [Fe(dmpe)2(C≡CR)-(CH3)] (1), are thermally stable in the presence of acetylenes; however, under UV irradiation, methane is lost with the formation of a metal bisacetylide. Photochemical metathesis of cis- or trans-[Fe(dmpe)2(CH3)(C≡CR)] (R = C6H5 (1a), 4-C6H4OCH3 (1b)) with terminal acetylenes was used to selectively synthesize unsymmetrically substituted iron(II) bisacetylide complexes of the type trans-[Fe(dmpe)2(C≡CR)(C≡CR′)] [R = Ph, R′ = Ph (6a), 4-CH3OC6H4 (6b), tBu (6c), Si(CH3)3 (6d), (CH2)4C≡CH (6e); R = 4-CH3OC6H4, R′ = 4-CH3OC6H4, (6g), tBu (6h), (CH2)4C≡CH (6i), adamantyl (6j)]. The structure of the unsymmetrical iron(II) bisacetylide complex trans-[Fe(dmpe)2(C≡CC6H5) (C≡CC6H4OCH3)] (6b) was determined by single-crystal X-ray diffraction. The photochemical metathesis of the bis-acetylene, 1,7-octadiyne, with trans-[Fe(dmpe)2(CH3)(C≡CPh)] (1a), was utilized to synthesize the bridged binuclear species trans,trans-[(C6H5C≡C)Fe(dmpe)2 (μ-C≡C(CH2)4C≡C)Fe(dmpe)2 (C≡CC6H5)] (11). The trinuclear species trans,trans,trans-[(C6H5C≡C)Fe(dmpe)2 (μ-C≡C(CH2)4C≡C)Fe(dmpe)2 (μ-C≡C(CH2)4C≡C)Fe(dmpe)2 (C≡CC6H5)] (12) was synthesized by the photochemical reaction of Fe(dmpe)2(C≡CPh)(C≡C(CH2)4 C≡-CH) (6e) with Fe(dmpe)2(CH3)2. Extended irradiation of the bisacetylide complexes with phenylacetylene resulted in insertion of the terminal alkyne into one of the metal acetylide bonds to give acetylide butenyne complexes. The structure of the acetylide butenyne complex, trans-[Fe(dmpe)2(C≡CC6H4 OCH3)(η1-C(C6H5)=CH (C≡CC6H4OCH3))] (9a) was determined by single-crystal X-ray diffraction.
