Synthesis and Some Reactions of Dichloro(pentamethylcyclopentadienyl)ruthenium(iii) Oligomer

Abstract

Paramagnetic ruthenium(III) complex, [(C5Me5)RuCl2]n, is prepared by the reaction of RuCl3·H2O with C5Me5H in refluxing ethanol. Treatment of [Cp*RuCl2]n (Cp* = C5Me5) with cyclic dienes or α,ω-bis(diphenylphosphino)alkanes gives diamagnetic Ru(II) complexes, Cp*RuCl(diene) or Cp*RuCl(dipos), respectively. Cationic diene complex of ruthenium is formed by the reaction of Cp*RuCl(2,5-norbornadiene) with AgBF4.

Ruthenium‐Catalyzed One‐Pot Double Allylation/Cycloisomerization of 1,3‐Dicarbonyl Compounds Leading to exo‐Methylenecyclopentanes

“…Later, a p-allylruthenium complex 2 b relevant to catalytic allylation was synthesized from [Cp*RuCl(cod)] (1) (Cp*= pentamethylcyclopentadienyl) [11] and cinnamyl chloride ( Figure 2). [12] The isolated 2 b was treated with excess acetylacetone at room temperature in the presence of COD and NMP to produce a monoallylated product as a single regioisomer in high yield.…”

Highly Selective Dimerization of Styrenes and Linear Co‐dimerization of Styrenes with Ethylene Catalyzed by a Ruthenium Complex

“…All solvents were distilled under argon with appropriate drying reagents (sodium or calcium hydride 2 ], [15] [Ru(h 4 -cod)(h 6 -cot)], [22] [Ru(h 5 -C 8 H 11 )(h 5 -C 6 H 5 O)]·PhOH, [18] [RuH 2 (PPh 3 ) 4 ], [23] [RuHCl(CO)(PPh 3 ) 3 ], [24] [RuCl 2 (PPh 3 ) 3 ], [25] and [Cp*RuCl(h 4 -cod)] [26] were prepared as described in the literature. Styrene derivatives 1 a-d were obtained commercially and used without further purification.…”

Ruthenium‐Catalyzed Cycloaddition of 1,6‐Diynes and Nitriles under Mild Conditions: Role of the Coordinating Group of Nitriles

“…[Cp*RuClA C H T U N G T R E N N U N G (cod)] was obtained according to the literature procedures. [27] General procedure for ruthenium-catalyzed cycloaddition: reaction of dimethyl dipropargylmalonate (2 a) with malononitrile (3 a): A solution of diyne 2 a (63 mg, 0.3 mmol) in dry degassed 1,2-dichloroethane (2 mL) was added to a solution of malononitrile (3 a) (30 mg, 0.45 mmol) and [Cp*RuClA C H T U N G T R E N N U N G (cod)] (1) (2.3 mg, 0.006 mmol) in dry degassed 1,2-dichloroethane (1 mL) over 15 min by using a syringe under Ar atmosphere at RT. The reaction mixture was stirred at RT for 20 h. The solvent was evaporated and the crude product was purified by silica-gel flash column chromatography (eluent hexane/AcOEt = 2:1) to give 4 aa (76 mg, 92 %) as orange solid.…”

“…The residue was purified by silica-gel-column flash chromatography (eluent, hexane/ AcOEt = 1:1) to afford 8 a (34.1 mg, 70 %) Computational methods: The Gaussian 03 program package was used for all geometry optimizations. [27] The geometries of model complexes I-IV were fully optimized by means of the Beckes three-parameter hybrid density functional method (B3 LYP) [28] with the basis set, consisting of a double-z basis set with the relativistic effective core potential of Hay and Wadt (LanL2 ECP) [29] for Ru, and the 6-31G(d) [30] basis sets for other elements.…”