SimplePhos ligands represent a novel class of monodentate chiral ligands based on a chiral amine moiety and flexible diaryl groups on the phosphorous atom. They can be easily prepared by two different pathways and they can be highly functionalised. Herein we report the copper-catalysed asymmetric conjugate addition of diethyl zinc and trialkylaluminium reagents with SimplePhos ligands, which gives high enantioselectivity with cyclic enones, acyclic enones and nitro-olefins, with up to 98.6% ee. Of particular interest is the reaction of trialkylaluminium reagents with a wide range of 3-substituted enones, thus allowing the formation of stereogenic quaternary carbon centres.

The design of chiral ligands is the key to attaining high asymmetric induction in transition-metal-catalyzed reactions. Subtle changes in the conformational, steric, and/or electronic properties of the chiral ligand can often lead to dramatic variation of the reactivity and enantioselectivity. As a result of strong substrate dependence in most cases, tunable and readily synthesized ligands are desirable to obtain high enantioselectivities.Nowadays, asymmetric copper-catalyzed conjugate addition and allylic substitution are well-developed methodologies for creating CÀC bonds. Many efforts have been made in designing efficient systems and identifying new ligands to improve enantioselectivities.

The design of chiral ligands is the key to attaining high asymmetric induction in transition-metal-catalyzed reactions. Subtle changes in the conformational, steric, and/or electronic properties of the chiral ligand can often lead to dramatic variation of the reactivity and enantioselectivity. As a result of strong substrate dependence in most cases, tunable and readily synthesized ligands are desirable to obtain high enantioselectivities.Nowadays, asymmetric copper-catalyzed conjugate addition and allylic substitution are well-developed methodologies for creating CÀC bonds. Many efforts have been made in designing efficient systems and identifying new ligands to improve enantioselectivities.

The first asymmetric Cu-catalyzed conjugate addition of dialkylzinc zinc reagents to a large scope of enals in presence of phosphoramidite, SimplePhos, or (R)-BINAP ligands with enantiomeric excesses up to 90% is reported. Moreover, ACA of Grignard reagents afforded moderate to good 1,4-regioselectivities with enantioselectivities up to 90%.

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meso-Hydrazines could be desymmetrised by ring-opening reactions by using various metal catalysts to form substituted cyclopentenes, which have a high synthetic potential. Herein, we report the asymmetric copper-catalysed ring opening of a range of polycyclic hydrazines with trialkylaluminium reagents and SimplePhos ligands with both high isolated yields and enantioselectivities of up to 95 %.

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