Welcome to the Straub Group
An octacopper hexaacetylide cluster salt with three bidentate ancillary N-heterocyclic carbene (NHC) ligands was prepared under acidic reaction conditions. This cluster is the first molecular copper acetylide complex that features high activity in the copper-catalyzed azide–alkyne cycloaddition (CuAAC), with added acetic acid even at -5 °C.
Fluktuierender Kupferacetylid-Cluster in der CuAAC-Katalyse
Fluxional Copper Acetylide Cluster in CuAAC Catalysis
Ata Makarem, Regina Berg, Frank Rominger, Bernd F. Straub*, Angew. Chem. 2015, 127, 7539-7543; Angew. Chem. Int. Ed. 2015, 54, 7431-7435.
The escaping lynx symbolizes the short lifetime of the first detected cationic copper carbene complex without heteroatom stabilization. The snow leopard that breaks a bar of his cage symbolizes the marginal silver-to-carbene back-bonding. Steric shielding by the IPr** ancillary ligand and the carbenes' substituents rendered possible the characterization of the greenish curry-yellow copper carbene complex and of the mint-green silver carbene complex, respectively.
Kupfer- und Silber-Carbenkomplexe ohne Heteroatom-Stabilisierung: Struktur, Spektroskopie und Relativistische Effekte
Copper and Silver Carbene Complexes without Heteroatom-Stabilization: Structure, Spectroscopy, and Relativistic Effects
Matthias W. Hussong, Wilhelm T. Hoffmeister, Frank Rominger, Bernd F. Straub*, Angew. Chem. 2015, 127, DOI: 10.1002/ange.201504117; Angew. Chem. Int. Ed. 2015, 54, DOI: 10.1002/anie.201504117, accepted for publication.
The captured tiger symbolizes the high electronic reactivity of the first isolated gold carbene complex without heteroatom stabilization. The full characterization of the emerald-green carbene complex reveals a significant Au=C back-bonding. The animated ball-and-stick model structure is derived from a single-crystal X-ray analysis: See gif animation (1024x768 resolution; 11 MB).
Isolierung eines nicht-Heteroatom-stabilisierten Goldcarbens
Isolation of a Non-Heteroatom-Stabilized Gold-Carbene Complex
Matthias W. Hussong, Frank Rominger, Petra Krämer, Bernd F. Straub*, Angew. Chem. 2014, 126, 9526-9529; Angew. Chem. Int. Ed. 2014, 53, 9372-9375 (announced as “hot paper”).
The lipophilic, water-stable, thermostable and cost-efficient aluminates "aletbate" and "aletpate" are halogen-free anions whose salts display a high tendency for crystallization and a high solubility in unpolar organic solvents. They are an environmentally more benign alternative for fluorinated and chlorinated weakly-coordinating anions.
Halogen-free water-stable aluminates as replacement for persistent fluorinated weakly-coordinating anions
Timo Söhner, Felix Braun, Lena Charlotte Over, Sven Mehlhose, Frank Rominger, Bernd F. Straub*, Green Chem. 2014, 16, DOI: 10.1039/c4gc00928b.
The sterically shielded gold complex IPr**AuNTf2 features remarkably high catalytic activity and stability. Alkyne hydration reactions and phenol syntheses proceed with high to excellent yields.
Mechanistic Investigations of a Stable, Highly Active, Extremely Sterically Shielded Molecular Gold Catalyst
Simone G. Weber, David Zahner, Frank Rominger, Bernd F. Straub*, ChemCatChem 2013, 5, 2330-2335.
A dinuclear copper complex features an unprecedented activity in homogeneous CuAAC "click" catalysis. This is the first direct evidence for the presence of two copper(I) atoms in the rate-limiting step in the reaction of organoazides and terminal alkynes to 1,4-disubstituted 1,2,3-triazoles.
Highly Active Dinuclear Copper Catalysts for Homogeneous Azide-Alkyne-Cycloadditions
Regina Berg, Johannes Straub, Ella Schreiner, Steffen Mader, Frank Rominger, Bernd F. Straub*, Adv. Synth. Catal. 2012, 354, 3445-3450.
Advancements in the mechanistic understanding of the copper-catalyzed azide–alkyne cycloaddition
Regina Berg*, Bernd F. Straub*, Beilstein J. Org. Chem. 2013, 9, 2715-2750.
Our EurJIC issue cover picture shows a Madagascar day gecko in a coconut with a locust on top. Gecko toes hold on to slithery surfaces due to van der Waals forces, which are also relevant for the lipophilic altebate anion.
A Lipophilic, Fluorine-Free, Thermostable, Inexpensive, S4-Symmetric, Highly Soluble, Weakly Coordinating, Protolabile Aluminate
Bernd F. Straub*, Michael Wrede, Karin Schmid, Frank Rominger, Eur. J. Inorg. Chem. 2010, 1907-1911.