Synthesis of [Ru2(CO)5{1,2-bis(.mu.-alkylamido)-1,2-bis(2-pyridyl)ethane}] and [Ru2(CO)4{pyridine-2-carbaldehyde N-alkylimine}2] and the molecular structure of bis(pyridine-2-carbaldehyde N-isopropylimine)tetracarbonyldiruthenium. Unprecedented CO-induced carbon-carbon bond formation between two pyridine-2-carbaldimines in dinuclear ruthenium carbonyl complexes

Transition Metal Catalyzed Reductive Cyclization Reactions of Nitroarenes and Nitroalkenes

“…The problem is remarkable when diimines are reacted with low valent ruthenium carbonyl compounds, such as those employed as catalysts for nitroarene reductive cyclization reactions, because easy breaking of the central CÀ C bond occurs. [55][56] With respect to most diimine ligands, BIAN derivatives are more rigid and this rigidity not only imposes the correct geometry for coordination, but also imparts a high chemical stability with respect to hydrolysis and rupture of the central CÀ C bond. [57][58] Ar-BIAN ligands have become quite popular in recent years for a number of reactions, but mostly in the field of palladium-and nickel-catalyzed polymerization of olefins.…”

“…Bis‐imines are typical ligands for transition metals, but they are weak compared to phenanthroline and simple diimines are easily decomposed if employed under forcing conditions. The problem is remarkable when diimines are reacted with low valent ruthenium carbonyl compounds, such as those employed as catalysts for nitroarene reductive cyclization reactions, because easy breaking of the central C−C bond occurs . With respect to most diimine ligands, BIAN derivatives are more rigid and this rigidity not only imposes the correct geometry for coordination, but also imparts a high chemical stability with respect to hydrolysis and rupture of the central C−C bond .…”

1,3-Dipolar cycloaddition to the FeSC fragment 20. Preparation and properties of carbonyliron complexes of di-thiooxamide. Reactivity of the mononuclear (di-thiooxamide)Fe(CO)3 towards dimethyl acetylenedicarboxylate

“…From these investigations two important conditions with respect to the 1,3-dipolar reactivity emerged; (i) since the Fe X C (X= NR, O) fragment can be classified as nucleophilic type I 1,3-dipole [22][23][24][25][26][27], a relatively high electron density is required [1,6,8,10,[28][29][30], and (ii) because the cycloaddition proceeds over the Fe X C (X= NR, O) fragment, the metal atom must be able to increase its co-ordination number and oxidation state.…”

Preparation and Properties of Carbonyliron Complexes of 1-Aza-4-oxa-1,3-butadiene (α-Imino Ketone) – X-ray Crystal Structures of Fe(CO)3[MeNC(Ph)C(Ph)=O] and Fe2(CO)4[tBuNC(H)(Me)C(O)(O)C(Me)C(H)=NtBu]

“…[1][2][3][4][5] The ability to donate the nitrogen lone pairs and the (CϭN) imine π-bonds results in a flexible coordination behaviour in which the α-diimine ligand can donate from 2 to 8 electrons to one or more metal centres. An interesting aspect of this versatile coordination behaviour is the activation of the imine bond towards C-C, C-H, C-N, and N-H coupling reactions of R-DAB ligands in the coordination sphere of transition metals with a variety of unsaturated molecules, such as α-diimines [6][7][8][9][10] carbodiimides [11] sulfines, [11] and alkynes. [12][13][14][15][16][17][18] In a series of previous papers [19][20][21][22][23][24] we have reported in detail on the C-C coupling reaction of the [(R-DAB)Fe(CO) 3 ] complexes 1 (cf.…”