C2-Symmetric tetrafluorobenzobarrelenes as highly efficient ligands for the iridium-catalyzed asymmetric annulation of 1,3-dienes with 2-formylphenylboron reagents
摘要:
New C-2-symmetric chiral diene ligands bearing a tetraflurobenzobarrelene framework were prepared via a [4+2] cycloaddition of 1,4-bis((methoxymethoxy)methyl)benzene with tetrafluorobenzyne. The diene ligands realized the iridium-catalyzed enantioselective [3+2] annulation of 1,3-dienes with 2-formylphenylboron reagents giving 1-indanol derivatives in high yields and with high enantioselectivities. (C) 2008 Elsevier Ltd. All rights reserved.
Iridium-Catalyzed [3 + 2] Annulation of 1,3-Dienes with ortho-Carbonylated Phenylboronic Acids. A Catalytic Process Involving Regioselective 1,2-Addition
摘要:
Annulation of 1,3-dienes with 2-formylphenylboronic acid proceeded with high regio- and stereoselectivity in the presence of a hydroxoiridium catalyst to give high yields of indanol derivatives. Various 1,3-dienes bearing electron-withdrawing and -donating substituents were successfully used under the catalytic conditions.