| Autor: |
Fowler JM; School of Chemistry, University of Leeds, Woodhouse Lane, Leeds LS2 9JT, UK. c.e.willans@leeds.ac.uk m.j.hardie@leeds.ac.uk., Britton E, Pask CM, Willans CE, Hardie MJ |
| Jazyk: |
angličtina |
| Zdroj: |
Dalton transactions (Cambridge, England : 2003) [Dalton Trans] 2019 Oct 07; Vol. 48 (39), pp. 14687-14695. |
| DOI: |
10.1039/c9dt03400e |
| Abstrakt: |
The trinuclear complexes [{PdI2(pyCl)}3(L1)] C1 and [{PdI2(pyCl)}3(L2)] C2, where pyCl = 3-chloropyridine, L1 = methyl(cyclotriguaiacylenyl)methylbenzimidazol-2-ylidene and L2 = benzyl(cyclotriguaiacylenyl)methylbenzimidazol-2-ylidene, each feature three palladium N-heterocyclic carbene (NHC) centres tethered onto a host-type cyclotriguaiacylene scaffold. Crystal structures of different solvates of complex C1 reveal different host-guest motifs including intra-cavity binding of dioxane guests concomitant with intramolecular halogen bonding interactions of C1. Mononuclear NHC analogues of C1 and C2, namely [PdI2(pyCl)(L3)] C3 and [PdI2(pyCl)(L4)] C4, where L3 = (3-chloropyridyl)-1-(2-methoxyphenyoxy)methyl-3-methylbenzimidazol-2-ylidene and L4 = (3-chloropyridyl)-1-(2-methoxyphenyoxy)methyl-3-benzylbenzimidazol-2-ylidene, were also synthesised and their crystal structures determined. Complexes C1-C4 are competent catalysts for Suzuki Miyaura cross-coupling, and interestingly exhibit a switch in the normal regioselectivity observed for reactions of 2,4-dibromopyridine with aryl boronic acids, usually C2-selective, yielding C4-arylated product preferentially over C2-arylated product. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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