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In homogeneous catalysis, C2-symmetric ligands refer to ligands that lack mirror symmetry but have C2 symmetry. Such ligands are usually bidentate and are valuable in catalysis. The C2 symmetry of ligands limits the number of possible reaction pathways and thereby increases enantioselectivity, relative to asymmetrical analogues. C2-symmetric ligands are a subset of chiral ligands. Chiral ligands, including C2-symmetric ligands, combine with metals or other groups to form chiral catalysts. These catalysts engage in enantioselective chemical synthesis, in which chirality in the catalyst yields chirality in the reaction product.
Metal-ligand cooperativity (MLC) is a mode of reactivity in which a metal and ligand of a complex are both involved in the bond breaking or bond formation of a substrate during the course of a reaction. This ligand is an actor ligand rather than a spectator, and the reaction is generally only deemed to contain MLC if the actor ligand is doing more than leaving to provide an open coordination site. MLC is also referred to as "metal-ligand bifunctional catalysis." Note that MLC is not to be confused with cooperative binding.
References
- ↑ Bader, Armin; Lindner, Ekkehard (April 1991). "Coordination chemistry and catalysis with hemilabile oxygen-phosphorus ligands". Coordination Chemistry Reviews. 108 (1): 27–110. doi:10.1016/0010-8545(91)80013-4.
- ↑ Braunstein, Pierre; Naud, Frédéric (16 February 2001). "Hemilability of Hybrid Ligands and the Coordination Chemistry of Oxazoline-Based Systems". Angewandte Chemie International Edition. 40 (4): 680–699. doi: 10.1002/1521-3773(20010216)40:4<680::AID-ANIE6800>3.0.CO;2-0 . PMID 11241595.
- ↑ Slone, Caroline S.; Weinberger, Dana A.; Mirkin, Chad A. (1999), "The Transition Metal Coordination Chemistry of Hemilabile Ligands", Progress in Inorganic Chemistry, John Wiley & Sons, Ltd, pp. 233–350, doi:10.1002/9780470166499.ch3, ISBN 978-0-470-16649-9 , retrieved 2021-04-02
- ↑ Braunstein, Pierre; Naud, Frédéric (2001). "Hemilability of Hybrid Ligands and the Coordination Chemistry of Oxazoline-Based Systems". Angewandte Chemie International Edition. 40 (4): 680–699. doi: 10.1002/1521-3773(20010216)40:4<680::AID-ANIE6800>3.0.CO;2-0 . ISSN 1521-3773. PMID 11241595.
- ↑ Miller, Eileen M.; Shaw, Bernard L. (1 January 1974). "Kinetic and other studies on oxidative addition reactions of iridium phosphine complexes of the type trans-[IrCl(CO)(PMe2R)2](R = Ph, o-MeO·C6H4, or p-MeO·C6H4)". Journal of the Chemical Society, Dalton Transactions (5): 480–485. doi:10.1039/DT9740000480.
- ↑ Nomura, Nobuyoshi; Jin, Jian; Park, Haengsoon; RajanBabu, T. V. (1 January 1998). "The Hydrovinylation Reaction: A New Highly Selective Protocol Amenable to Asymmetric Catalysis". Journal of the American Chemical Society. 120 (2): 459–460. doi:10.1021/ja973548n.
- ↑ RajanBabu, T. V. (1 August 2003). "Asymmetric Hydrovinylation Reaction". Chemical Reviews. 103 (8): 2845–2860. doi:10.1021/cr020040g. PMID 12914483.
- ↑ Verdaguer, Xavier; Moyano, Albert; Pericàs, Miquel A.; Riera, Antoni; Maestro, Miguel Angel; Mahía, José (1 October 2000). "A New Chiral Bidentate (P,S) Ligand for the Asymmetric Intermolecular Pauson−Khand Reaction". Journal of the American Chemical Society. 122 (41): 10242–10243. doi:10.1021/ja001839h.
- ↑ Jiménez, M. Victoria; Fernández-Tornos, Javier; Pérez-Torrente, Jesús J.; Modrego, Francisco J.; Winterle, Sonja; Cunchillos, Carmen; Lahoz, Fernando J.; Oro, Luis A. (24 October 2011). "Iridium(I) Complexes with Hemilabile N-Heterocyclic Carbenes: Efficient and Versatile Transfer Hydrogenation Catalysts" (PDF). Organometallics. 30 (20): 5493–5508. doi:10.1021/om200747k. hdl:10261/57986.