The catalytic performance of Ru–NHC alkylidene complexes: PCy3 versus pyridine as the dissociating ligand

نویسندگان

  • Stefan Krehl
  • Diana Geißler
  • Sylvia Hauke
  • Oliver Kunz
  • Lucia Staude
  • Bernd Schmidt
چکیده

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 in cross metathesis reactions.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Stability of Second Generation Grubbs Alkylidenes to Primary Amines: Formation of Novel Ruthenium-Amine Complexes

The stability of second generation Grubbs alkylidenes to primary amines relative to the first generation derivatives is investigated. For both Grubbs alkylidene derivatives, the tricyclohexylphosphine (PCy3) ligand is displaced by n-butylACHTUNGTRENNUNGamine and diethylenetriamine. However, while displacement of PCy3 in first generation Grubbs alkylidene derivatives results in decomposition of ...

متن کامل

Stable ruthenium indenylidene complexes with a sterically reduced NHC ligand.

Stable and active Ru olefin metathesis catalyst 7 bearing a sterically reduced NHC ligand was synthesized. Upon action of pyridine, 7 forms complex 24, the first example of an Ru–indenylidene catalyst bearing a labile pyridine ligand and a sterically less demanding NHC ligand.

متن کامل

Gold (I) Complexes of 2,2'-Biimidazolate Ligand: Syntheses and Spectral Properties of Hetero-polymetallic Complexes Having Ru2Au2 Core

The reaction of [Ru(L)2(H2biim)](ClO4)2 [L1 = 2,2¢-bipyridine (bpy) or L2 =  2-(phenylazo)pyridine (pap) and H2biim = 2,2¢-biimidazole] with Au(tht)Cl (tht = tetrahydrothiophene) in presence of base in methanol produced a terametallic cationic complex [{Ru(L)2(biim)}<s...

متن کامل

Hexacoordinate Ru-based olefin metathesis catalysts with pH-responsive N-heterocyclic carbene (NHC) and N-donor ligands for ROMP reactions in non-aqueous, aqueous and emulsion conditions

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...

متن کامل

Cyclic ruthenium-alkylidene catalysts for ring-expansion metathesis polymerization.

A series of cyclic Ru-alkylidene catalysts have been prepared and evaluated for their efficiency in ring-expansion metathesis polymerization (REMP). The catalyst structures feature chelating tethers extending from one N-atom of an N-heterocyclic carbene (NHC) ligand to the Ru metal center. The catalyst design is modular in nature, which provided access to Ru complexes having varying tether leng...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره 6  شماره 

صفحات  -

تاریخ انتشار 2010