Synthesis and structural characterization of 20-membered macrocyclic rings bearing trans-chelating bis(N-heterocyclic carbene) ligands and the catalytic activity of their palladium(ii) complexes

Dalton Transactions : an International Journal of Inorganic Chemistry
Rajesh Thapa, Stefan M Kilyanek

Abstract

Macrocycles consisting of a 20-membered ring containing two imidazolium salt functionalities and of the formula [PhCH2N(CH2CH2CH2)Im(CH2CH2CH2)2][Br]2 (Im = imidazole = 3a, benzimidazole = 3b) were synthesized in 70-75% yields. These salts serve as precursors to macrocycles containing two N-heterocyclic carbene (NHC) moieties. Reaction of the macrocyclic salts 3a and 3b with silver oxide afforded macrocyclic-bis(NHC)silver(i) complexes 4a and 4b. Single-crystal X-ray diffraction studies of macrocyclic-bis(NHC)silver(i) complex 4a revealed a tetranuclear silver core with a short Ag-Ag distance (2.9328 Å). Complexes 4a and 4b serve as carbene transfer reagents to Pd. The treatment of macrocyclic-bis(NHC)silver(i) complexes 4a and 4b with one equivalent of PdCl2(MeCN)2 in methylene chloride afforded square-planar trans-macrocyclic-bis(NHC)Pd(ii)X2 complexes 5a and 5b. Preliminary screening of these palladium complexes showed they are competent precatalysts for Heck and Suzuki coupling reactions.

References

May 11, 2000·Organic Letters·D S ClyneT V RajanBabu
Dec 29, 2000·Chemistry : a European Journal·M R de JongD N Reinhoudt
Oct 10, 2002·Chemical Reviews·Alain RoucouxHenri Patin
Mar 11, 2004·Chemical Communications : Chem Comm·Richard E DouthwaiteBenson M Kariuki
Jul 21, 2004·Chemical Communications : Chem Comm·Manfred T Reetz, Johannes G de Vries
Nov 10, 2005·Chemical Reviews·Jered C Garrison, Wiley J Youngs
Jul 12, 2007·Dalton Transactions : an International Journal of Inorganic Chemistry·Jennifer HoughtonBenson M Kariuki
Sep 9, 2008·Accounts of Chemical Research·Nicolas Marion, Steven P Nolan
Mar 5, 2009·Dalton Transactions : an International Journal of Inorganic Chemistry·Brad P MorganRhett C Smith
Mar 14, 2009·Chemical Reviews·Daniela TapuChristopher Roe
Jul 11, 2009·Chemical Reviews·Silvia Díez-GonzálezSteven P Nolan
Apr 15, 2002·Angewandte Chemie·Wolfgang A Herrmann
May 8, 2010·Dalton Transactions : an International Journal of Inorganic Chemistry·Murray V BakerAllan H White
Oct 21, 2010·Chemistry : a European Journal·Christian RadloffF Ekkehardt Hahn
Dec 1, 2010·Dalton Transactions : an International Journal of Inorganic Chemistry·Sarim DastgirMalcolm L H Green
Oct 19, 2011·Angewandte Chemie·Christina Moberg
Jan 19, 2013·Dalton Transactions : an International Journal of Inorganic Chemistry·Christian Schulte to BrinkeF Ekkehardt Hahn
Feb 6, 2013·Dalton Transactions : an International Journal of Inorganic Chemistry·Soraya N SluijterCornelis J Elsevier
Feb 26, 2013·The Journal of Physical Chemistry. B·Su ChenEkaterina I Izgorodina
Nov 10, 2013·Dalton Transactions : an International Journal of Inorganic Chemistry·Rhiann E Andrew, Adrian B Chaplin
Jun 27, 2014·Nature·Matthew N HopkinsonFrank Glorius
Dec 30, 2014·Acta Crystallographica. Section A, Foundations and Advances·George M Sheldrick
Jan 9, 2015·Acta Crystallographica. Section C, Structural Chemistry·George M Sheldrick
Jun 20, 2015·Journal of Applied Crystallography·Lennard KrauseDietmar Stalke
Jul 29, 2015·Dalton Transactions : an International Journal of Inorganic Chemistry·Daniel T WeissFritz E Kühn
May 20, 2016·Dalton Transactions : an International Journal of Inorganic Chemistry·Marco MonticelliPeter J Barnard
May 27, 2016·Inorganic Chemistry·Manuela HolleringFritz E Kühn
Jun 26, 2018·Chemical Reviews·Shigeki Kuwata, F Ekkehardt Hahn

❮ Previous
Next ❯

Citations


❮ Previous
Next ❯

Methods Mentioned

BETA
X-ray
NMR
Suzuki

Related Concepts

Related Feeds

Alternative Complement Pathway

The Alternative Complement Pathway is part of the innate immune system, and activation generates membrane attack complexes that kill pathogenic cells. Discover the latest research on the Alternative Complement Pathway.