Unsymmetrical Ru-NHC catalysts: a key for the selective tandem ring opening-ring closing alkene metathesis (RO-RCM) of cyclooctene.
نویسندگان
چکیده
Dissymmetry for selectivity: NHC ligand with two different pendant group allows the selective formation of cyclic oligomers in place of polymers opening new strategy to generate macrocycles.
منابع مشابه
The catalytic performance of Ru–NHC alkylidene complexes: PCy3 versus pyridine as the dissociating ligand
The catalytic performance of NHC-ligated Ru-indenylidene or benzylidene complexes bearing a tricyclohexylphosphine or a pyridine ligand in ring closing metathesis (RCM), cross metathesis, and ring closing enyne metathesis (RCEYM) reactions is compared. While the PCy₃ complexes perform significantly better in RCM and RCEYM reactions than the pyridine complex, all catalysts show similar activity ...
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Three new ruthenium alkylidene complexes (PCy3)Cl2(H2ITap)Ru=CHSPh (9), (DMAP)2Cl2(H2ITap)Ru=CHPh (11) and (DMAP)2Cl2(H2ITap)Ru=CHSPh (12) have been synthesized bearing the pH-responsive H2ITap ligand (H2ITap = 1,3-bis(2',6'-dimethyl-4'-dimethylaminophenyl)-4,5-dihydroimidazol-2-ylidene). Catalysts 11 and 12 are additionally ligated by two pH-responsive DMAP ligands. The crystal structure was s...
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ورودعنوان ژورنال:
- Dalton transactions
دوره 40 46 شماره
صفحات -
تاریخ انتشار 2011