Synthesis and Characterization of Bimetallic Ruthenium Complexes Bridged with C₅H and Related Ligands

Abstract

Treatment of [(η5-C5R5)Ru(L)2]BF4 (R = Me, (L)2 = dppe; R = H, (L)2 = (PPh3)2) with 0.45 equiv of HC⋮CCH(OH)C⋮CH led to the formation of the C5H2-bridged compounds [(η5-C5R5)(L)2RuCCCHCHCRu(L)2(η5-C5R5)](BF4)2. The C5H2-bridged compounds reacted with alumina to give the C5H-bridged compounds [(η5-C5R5)(L)2RuCCCHC⋮CRu(L)2(η5-C5R5)]BF4. The structure of the C5H-bridged complex [Cp(PPh3)2RuCCCHC⋮CRu(PPh3)2Cp]BPh4 has been confirmed by X-ray diffraction and shows the bridging C5H ligand to be symmetric with a delocalized π-system. Reaction of [(η5-C5R5)(L)2RuCCCHC⋮CRu(L)2(η5-C5R5)]BF4 with acetone in the presence of KOH or KOBu t produced (η5-C5R5)(L)2RuC⋮CCH(CH2COMe)C⋮CRu(L)2(η5-C5R5).

Comparison of the bis(ferrocenylethynyl)phenylmethylium cation with bis(ferrocenylethenyl)methylium analogues

“…2) as interesting targets and here we describe some synthetic studies aimed at obtaining cations of the form [(FcCC) 2 CR] + . Related AC"CCRC"CAbridged cations with the Cp(PR 3 ) 2 RuA end group have been reported; these have been shown to be symmetrical in solution on the NMR timescale and, in one case, in the solid state by X-ray crystallography [16]. Several reactions of (PhCC) 2 CHOH under acid conditions, including conversion to PhC"CCH@C@ CPhBr and PhC"CCH@CHC(O)Ph, presumably involve [(PhCC) 2 CH] + as an intermediate [17].…”

Cyanine‐Like Dyes with Large Bond‐Length Alternation

“…A one-pot method was adopted by combining published procedures. [10,24] Synthesis of 3-ethynyl-1-methyl-2-phenyl-indole (5 b): Removal of the protecting group was achieved by adapting a published procedure. [26] Protected acetylene indole 4 b (0.450 g, 1.55 mmol) was dissolved in toluene (75 mL), and freshly ground sodium hydroxide (1.24 g, 31.1 mmol) was added.…”

“…A ruthenium-stabilized ethynyl cation, which was stable under anaerobic conditions, has also been reported. [10] Herein, we present the synthesis of alkyne-bridged cyanine analogues and explore the effect of the inherent bondlength alternation and chemical structure on the molecular Abstract: Herein, the synthesis and properties of alkyne-bridged carbocat-A C H T U N G T R E N N U N G ions, which are analogous in structure to cyanine dyes, are reported. An alkene-bridged dye, linked at the third position of the indole, was also synthesized as a reference compound.…”

Some ruthenium complexes containing cyanocarbon ligands: syntheses, structures and extent of electronic communication in binuclear systems

“…However, we have been unable to perform this transformation (using NaOMe, LiMe, KOBu t or LiH as bases), since the presence of the two nitrogen atoms would undoubtedly make this species considerably more basic than the related complexes [{Cp(R 3 P) 2 M}‚C‚ C‚CHC"C{M(PR 3 ) 2 Cp}]BF 4 [M = Fe, (PR 3 ) 2 = dppe; M = Ru, Os, PR 3 = PPh 3 ], whose syntheses were described by Jia [26]. Attempts to prepare complexes containing the l-C 5 ligand by treating the cations with [CPh 3 ] + or with strong bases were unsuccessful.…”