These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Palladium N(CH2CH2P(i)Pr2)2-dialkylamides: synthesis, structural characterization, and reactivity.
    Author: Marziale AN, Herdtweck E, Eppinger J, Schneider S.
    Journal: Inorg Chem; 2009 Apr 20; 48(8):3699-709. PubMed ID: 19281205.
    Abstract:
    Palladium(II) aminodiphosphine PNP pincer complexes [PdR(PNP(H))]PF(6) (1(R); R = Cl Me, Ph; PNP(H) = HN(CH(2)CH(2)P(i)Pr(2))(2)) were prepared. Deprotonation with KO(t)Bu affords dialkylamides [PdR(PNP)] (2(R); R = Cl Me, Ph; PNP = (NCH(2)CH(2)P(i)Pr(2))(2)) in high yield which are stable toward beta-H elimination. While AgPF(6) oxidizes the amides, cationic amido complexes [PdL(PNP)]PF(6) (3(L); L = CN(t)Bu, PMe(3)) were obtained upon chloride abstraction from 1(Cl) with TlPF(6). The reaction of amide 2(Cl) with MeOTf results in N-methylation yielding [PdCl(PNP(Me))]OTf (5) quantitatively. N-H acidities of the amino complexes 1(Me) (pK(a) = 24.2(1)) and 1(Ph) (pK(a) = 23.2(1)) were determined in dmso. Complexes 1(Cl), 1(Me), 2(Cl) 2(Me), 3(CNtBu), and 5 were structurally characterized by single crystal X-ray diffraction. The amido complexes feature pyramidal nitrogen atoms in the solid state. The molecular structures, high N-basicity, and reactivity of the amido complexes can be explained with Pd-N(amido) bonding that is characterized by strong N-->Pd sigma-donation and repulsive d(pi)-p(pi) pi-interactions. This interpretation was confirmed by density functional theory (DFT) calculations of 2(Cl).
    [Abstract] [Full Text] [Related] [New Search]