Stereodirecting ligands

Gabriele B, Salerno G, Costa M (2006) Oxidative Carbonylations. 18 239-272 Gade LH, Bellemin-Laponnaz S (2006) Chiral N-Heterocyclic Carbenes as Stereodirecting Ligands in Asymmetric Catalysis. 21 117-157 Gade LH, see Kassube JK (2006) 20 61-96 Gandon V, see Aubert C (2006) 19 259-294 Garcia JI, see Fraile JM (2005) 15 149-190... 

Gade, L.H. and Bellemin-Laponnaz, S. (2007) Chiral N-heterocyclic carbenes as stereodirecting ligands in asymmetric catalysis. Top. Organomet. Chem., 21, 117-157. 

Chiral N-Heterocydic Carbenes as Stereodirecting Ligands in Asymmetric Catalysis... 

The stereodirecting ligands containing the 1,2-diphenylethylenediamine backbone gives higher enantioselectivities than the ones with the 1,2-diaminocyclohexane skeleton. 

In conclusion, while the first chiral imidazolinylidenes tested in asymmetric catalysis only gave a moderate chiral induction, more recent results have clearly indicated that the encoding of chiral information in the backbone of the heterocycle may give rise to highly efficient stereodirecting ligands. The potential versatility of this approach is apparent in a recent contribution... 

Cesar V, Bellemin-Laponnaz S, Gade LH (2004) Chiral A-heterocyclic car-benes as stereodirecting ligands in asymmetric catalysis. Chem Soc Rev 33 619... 

Modular Assembly of Chiral Catalysts with Polydentate Stereodirecting Ligands... 

Pfaltz and coworkers [29] had previously investigated the allylic alkylation of l,3-diphenylprop-2-enyl acetate with dimethyl malonate as nucleophile (in the presence of A/ ,0-bis(trimethylsilyl)acetamide, BSA) with the well-established BOX ligands as stereodirecting ligands, and this particular system therefore provided the point of reference for the catalytic study at hand (Table 15.3, entry 1) [28]. Under the reaction conditions displayed in Scheme 15.4, the trisoxazoline-based catalysts generally induce a better enantioselectivity compared to their BOX analogs, and this behavior appears to be independent of the substituent, as shown in Table 15.3. 

The Boxmi Pincer System a Highly Efficient Modular Stereodirecting Ligand for a Broad Range of Catalytic Reactions... 

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