Synthesis of bis-oxazoline-ruthenium(II)-arene complexes.

Homologation of Monoterpenoids into New Sesquiterpenoids via Tandem Isomerisation/Claisen Rearrangement Reactions with Three‐Component Ruthenium Catalysts, and Ru(methallyl)2(COD) Revealed by High Throughput Screening Techniques

“…Starting from these observations, variations on the catalytic system and especially the use of bidentate ligands such as bisbenzoxazole, [16] chiral bisoxazoline and diimine, [17] associated with a ruthenium source, have shown isomerisation capability. The most efficient catalytic system B was then evaluated for terpenoids.…”

Access to 3‐Methyl‐4‐methylene‐N‐tosylpyrrolidine and 3,4‐DimethylN‐tosylpyrroline by Ruthenium‐Catalyzed Cascade Cycloisomerization/Isomerization Reactions

“…[1] Especially, a variety of RuX 2 (arene)(L) complexes promoting catalytic reactions such as nucleophilic addition to triple bonds to form furans (L ϭ imidazoline, tetrahydropyrimidine, [2] benzimidazole [3] ), hydrogen transfer (L ϭ amino acid, [4] amino alcohol, [5] diamine [6] ), cyclopropanation (L ϭ diamine [7] ), or DielsϪAlder cycloaddition and Claisen rearrangement [L ϭ bis(oxazoline) [8,9] ]. It is also well established that RuCl 2 (arene)(L) complexes can easily be transformed by activation of propargylic alcohols into cationic ruthenium(allenylidene) complexes, which have shown catalytic properties in olefin metathesis.…”

New [Ru3(CO)12]‐Based Catalysts with Imidazolinium Salt, Diimine, or Bis(oxazoline) Ligands and Ruthenium Bis(oxazoline) Complex for Tandem Isomerisation/Claisen Rearrangement of Dienyl Ethers − X‐ray Structure of [RuCl{(R,R)‐bis(isopropyloxazoline)}(p‐cymene)]BF4

“…Scheme 8 The bis(oxazoline) 17 was then used to prepare a welldefined ruthenium() (arene) complex according to the procedure we previously used for achiral bis(oxazoline)ruthenium complexes. [17] Two equiv. of the bis(oxazoline) 17 were reacted with the ruthenium complex [RuCl 2 (p-cymene)] 2 in methanol at room temperature with two equiv.…”

“…Since well-defined chelating dinitrogen containing ruthenium complexes of type [RuCl{bis(oxazoline)}(arene)] ϩ X Ϫ have already shown some activity for this reaction, [17] we have explored the catalyst modification based on [Ru 3 (CO) 12 ], as a ruthenium source, by replacing the bulky imidazolinylidene precursor by a sterically hindered diimine or bis(oxazoline)ligand.…”