Synthesis and Characterization of Novel Guanidine Ligands Featuring Biphenyl or Binaphthyl Backbones

N-Heterocyclic Carbene Adducts of Main Group Elements and Their Use as Ligands in Transition Metal Chemistry

N-Heterocyclic carbenes (NHC) are nowadays ubiquitous and indispensable in many research fields, and it is not possible to imagine modern transition metal and main group element chemistry without the plethora of available NHCs with tailor-made electronic and steric properties. While their suitability to act as strong ligands toward transition metals has led to numerous applications of NHC complexes in homogeneous catalysis, their strong σ-donating and adaptable π-accepting abilities have also contributed to an impressive vitalization of main group chemistry with the isolation and characterization of NHC adducts of almost any element. Formally, NHC coordination to Lewis acids affords a transfer of nucleophilicity from the carbene carbon atom to the attached exocyclic moiety, and low-valent and low-coordinate adducts of the p-block elements with available lone pairs and/or polarized carbon-element π-bonds are able to act themselves as Lewis basic donor ligands toward transition metals. Accordingly, the availability of a large number of novel NHC adducts has not only produced new varieties of already existing ligand classes but has also allowed establishment of numerous complexes with unusual and often unprecedented element-metal bonds. This review aims at summarizing this development comprehensively and covers the usage of N-heterocyclic carbene adducts of the p-block elements as ligands in transition metal chemistry.

Metal-catalysed reactions enabled by guanidine-type ligands

A review of metal–guanidine complexes, which are selective and powerful catalysts for organic transformations, asymmetric synthesis, and polymerisation.

Tetraethylammonium (acetonitrile)trichloridopalladate(II)

A new square-planar palladium complex salt, (C8H20N)[PdCl3(C2H3N)], has been formed with one of the Cl atoms in tetrachloridopalladate(II) replaced by an acetonitrile coordinated through the N atom. This compound could be a useful precursor for synthesis of palladium complexes. The complex salt crystallizes in the monoclinicP21/cspace group.

Coordination and insertion of alkenes and alkynes in AuIII complexes: nature of the intermediates from a computational perspective

Computational studies show how the stability and reactivity of gold(iii) alkene and alkyne complexes depend on the ancillary ligands.

Two C2-symmetric chelating P2-bisphosphazene superbases connected via a binaphthyl backbone – synthesis, structural features and preparation of a cationic alkyl aluminum complex

Two P₂-phosphazene Schwesinger bases were combined into a stereorigid chiral tetraphosphazene superbase and superdonor.