Cationic [Ru(eta(5)-C5H5)(CH3CN)(3)](+) complex, tris(acetonitrile)(cyclopentadienyl)ruthenium(II), gives rise to a very rich organometallic chemistry. Combined with diimine ligands, and 1,10-phenanthroline in particular, this system efficiently catalyzes diazo decomposition processes to generate metal-carbenes which undergo a series of original transformations in the presence of Lewis basic substrates. Herein, syntheses and characterizations of [CpRu(Phen)(L)] complexes with (large) lipophilic non-coordinating (PF6- and BArF-) and coordinating TRISPHAT-N- anions are reported. Complex [CpRu(eta(6)-naphthalene)][BArF] ([1][BArF]) is readily accessible, in high yield, by direct counterion exchange between [1][PF6] and sodium tetrakis[3,5-bis(trifluoromethyl)phenyl]borate (NaBArF) salts. Ligand exchange of [1][BArF] in acetonitrile generated stable [Ru(eta(5)-C5H5)(CH3CN)(3)][BArF] ([2][BArF]) complex in high yield. Then, the desired [CpRu(Phen)(CH3CN)] ([3]) complexes were obtained from either the [1] or [2] complex in the presence of the 1,10-phenanthroline as ligand. For characterization and comparison purposes, the anionic hemilabile ligand TRISPHAT-N (TTN) was introduced on the ruthenium center, from the complex [3][PF6], to quantitatively generate the desired complex [CpRu(Phen)(TTN)] ([4]) by displacement of the remaining acetonitrile ligand and of the PF6- anion. Solid state structures of complexes [1][BArF], [2][BArF], [3][BArF], [3][PF6] and [4] were determined by X-ray diffraction studies and are discussed herein.

Cationic [Ru(η 5 -C 5 H 5 )(CH 3 CN) 3 ] + complex, tris(acetonitrile)(cyclopentadienyl)ruthenium(II), gives rise to a very rich organometallic chemistry. Combined with diimine ligands, and 1,10-phenanthroline in particular, this system efficiently catalyzes diazo decomposition processes to generate metal-carbenes which undergo a series of original transformations in the presence of Lewis basic substrates. Herein, syntheses and characterizations of [CpRu(Phen)(L)] complexes with (large) lipophilic non-coordinating (PF 6− and BAr F− ) and coordinating N-TRISPHAT − anions are reported. Complex [CpRu(η 6 -naphthalene)][BAr F ] [1][BAr F ] is readily accessible, in high yield, by direct counterion exchange between [1][PF 6 ] and sodium tetrakis[3,5-bis(trifluoromethyl)phenyl]borate (NaBAr F ) salts. Ligand exchange of [1][BAr F ] in acetonitrile generated stable [Ru(η 5 -C 5 H 5 )(CH 3 CN) 3 ][BAr F ] [2][BAr F ] complex in high yield. Then, the desired [CpRu(Phen)(CH 3 CN)] [3] complexes were obtained from either the [1] or [2] complex in the presence of the 1,10-phenanthroline as ligand. For characterization and comparison purposes, the anionic hemilabile ligand TRISPHAT-N (TTN) was introduced on the ruthenium center, from the complex [3][PF 6 ] , to quantitatively generate the desired complex [CpRu(Phen)(TTN)] [4] by displacement of the remaining acetonitrile ligand and of the PF 6− anion. Solid state structures of complexes [1][BAr F ] , [2][BAr F ] , [3][BAr F ] , [3][PF 6 ] and [4] were determined by X-ray diffraction studies and are discussed herein.

1,4-Dioxepines result from the decomposition of α-diazo-β-keto esters in the presence of oxetanes using the catalytic combination of the (cyclopentadienyl)ruthenium complex [CpRu(CH3CN)3][BArF] and 1,10-phenanthroline. The regioselective [4+3] insertions follow an SN1-like mechanism and occur yet enantiospecifically (es 74%). The retention of configuration was ascertained by vibrational circular dichroism (VCD) and solid state analyses. Furans, products of [4+1] insertions, are only observed as traces in the above protocol. To promote their formation under CpRu catalysis, it is necessary to use a two-step process with γ-halogenated alcohols as substrates.

N-aryl γ-lactams react intermolecularly with acceptor-acceptor diazo reagents, usually dicarbonyl compounds, in a copper-catalyzed process to yield functionalized pyrrolidines with α-pseudoquaternary centers. As 1,2-acyl or -phosphoryl migration is preferred, single regioisomers are obtained. Furthermore, in the presence of a Lewis acid, subsequent Friedel-Crafts reactions yield tricyclic pyrrolizidines in excellent yields (90-96 %) and diastereoselectivities (up to >20:1).

Reactions of α-diazo-β-ketoesters with cyclic ketones, lactones, and carbonates are reported. Thanks to the combined use of salt [CpRu(CH3CN)3][BArF] and 1,10-phenanthroline as catalyst for the diazo decomposition, effective and practical syntheses of spiro bicyclic ketals, orthoesters, and orthocarbonates are afforded.

AbstractA large range of cyclic carbonyl compounds, including steroid derivatives, are converted to the title products following a mild and efficient protocol.

The asymmetric bromine-lithium exchange on a series of prochiral biphenyls was investigated. As in many asymmetric organolithium reactions, the chiral ligand (here a diamine) was considered to be the enantiocontrolling element. We show here that the organolithium reagent also plays an important role.

(Cyclopentadienyl) tris(acetonitrile) ruthenium hexafluorophosphate [CpRu(CH3CN)(3)][PF6] in combination with pyridine-hydrazone ligands efficiently catalyzes the asymmetric decarboxylative allylic rearrangement of allyl aryl carbonates. Formation of C-O bonds with high regio- and enantio-selectivity ratios (up to 95: 5 and 98% ee) is obtained. Good stereocontrol of the pseudotetrahedral geometry of the CpRu moiety is achieved by the hydrazone ligand and its "electron-poor" nature is evidenced through the epimerization of the hexa-coordinated TRISPHAT-N anion.

Strong cooperative interactions result in light-induced bistability between the high-spin and the low-spin state.