0000000001301527
AUTHOR
Thomas Quell
Scalable and Selective Preparation of 3,3′,5,5′-Tetramethyl-2,2′-biphenol
Biphenols are indispensable building blocks in ligand systems for organic catalysis. 3,3′5,5′-Tetramethyl-2,2′-biphenol is a particular versatile motif in different catalytic systems. We developed an easy to perform and scalable process to give access to large quantities of this important building block by the use of selenium dioxide, a common and readily available oxidizer.
ChemInform Abstract: Solvent-Dependent Facile Synthesis of Diaryl Selenides and Biphenols Employing Selenium Dioxide.
The reaction of phenols (I) with selenium dioxide in pyridine leads to diaryl selenides (IIa-d), whilst the reaction in acetic acid gives rise to biphenols (III).
Crystal structure of 12-benzylsulfanyl-2,9-dibromo-6H-dibenzo[b,g][1,8]naphthyridin-11-one
The hetero-tetra-cene skeleton of the title mol-ecule, C23H14Br2N2OS, is defined by linear annulation of four six-membered rings, including two N heteroatoms. This moiety is nearly planar (r.m.s. deviation = 0.055 Å), with a slight twist of 4.1 (2)° between the two halves of the aromatic system. The dihedral angle between the least-squares plane of the skeleton and the benzyl group is 24.5 (3)°; the C-S-C angle involving the benzyl-sulfanyl group is 99.2 (4)°. In the crystal, mol-ecules are π-stacked in an anti-parallel fashion along [110], with a distance between the aromatic planes of 3.47 (2) Å. Inter-molecular N-H⋯O hydrogen bonds form chains extending parallel to [001] and bridge the a…
CCDC 1429063: Experimental Crystal Structure Determination
Related Article: Thomas Quell, Michael Mirion, Dieter Schollmeyer, Katrin M. Dyballa, Robert Franke, Siegfried R. Waldvogel|2016|ChemistryOpen|5|115|doi:10.1002/open.201500206