Two Stereoinduction Events in One C−H Activation Step: A Route towards Terphenyl Ligands with Two Atropisomeric Axes. Issue 17 (13th March 2018)

• Record Type: Journal Article
• Authors: Dherbassy, Quentin; Djukic, Jean‐Pierre; Wencel‐Delord, Joanna; Colobert, Françoise
• Is Part Of: Angewandte Chemie international edition. Volume 57:Issue 17(2018)
• Page Start: 4668
• Page End: 4672
• Publication Date: 2018-03-13
• Subjects: asymmetric C−H activation -- atropisomerism -- axial chirality -- chiral ligands -- sulfoxides; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201801130
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: Herein we disclose the synthesis of original chiral scaffolds— ortho ‐orientated terphenyls presenting two atropisomeric Ar–Ar axes. These unusual structures were built up by using the C−H activation approach, and remarkably, both chiral axes were controlled with excellent stereoselectivity in a single transformation. During the reaction, not only does atroposelective functionalization of a biaryl precursor occur to establish one stereogenic axis, but an unprecedented atropo‐stereoselective C−H arylation also takes place to generate the second stereogenic element. These enantiomerically pure ortho ‐terphenyls show an original tridimensional structure and thus constitute a unique foundation for building up a library of enantiomerically pure bidentate ligands, such as the new ligands S/N‐Biax and diphosphine BiaxPhos. Abstract : Double, without the trouble : Unusual chiral scaffolds— ortho ‐orientated terphenyls presenting two atropisomeric Ar –Ar axes—were constructed by a C−H activation approach, in which both stereogenic axes were controlled with excellent stereoselectivity in a single transformation (see scheme). The chiral ortho ‐terphenyl products with their original three‐dimensional structure form a unique architecture for novel bidentate ligands.