(4+3) Annulation of Donor‐Acceptor Cyclopropanes and Azadienes: Highly Stereoselective Synthesis of Azepanones
作者:Stefano Nicolai、Jérôme Waser
DOI:10.1002/anie.202209006
日期:2022.9.5
Azepanones are important and widespread seven-membered heterocycles, but their synthesis is challenging. A convergent method to access these scaffolds was developed relying on a (4+3) annulation reaction of azadienes and donor-acceptor cyclopropanes. Good to excellent yields and high diastereoselectivity were achieved using Yb(OTf)3 as the catalyst. Asymmetric induction was possible with Cu(OTf)2 in
Electronic effects of aryl-substituted bis(oxazoline) ligands on the outcome of asymmetric copper-catalysed C–H insertion and aromatic addition reactions
作者:Catherine N. Slattery、Sarah O’Keeffe、Anita R. Maguire
DOI:10.1016/j.tetasy.2013.09.009
日期:2013.10
The effect of the modification of bis(oxazoline) ligands on the outcome of copper-catalysed C-H insertion and aromatic addition reactions is described. In general, these reactions display minimum sensitivity in terms of enantiocontrol to variation of the electronic properties of the aryl moiety of the ligand however, some influence is observed for C-H insertions employing naphthyl-substituted bis(oxazolines) and for aromatic addition reactions of biphenyl diazo ketone substrates. The synthesis of the modified bis(oxazolines), which include four novel structures, is also described. (C) 2013 Elsevier Ltd. All rights reserved.