Ir-Catalyzed C−H Amidation of Aldehydes with Stoichiometric/Catalytic Directing Group
作者:Yun-Fei Zhang、Bin Wu、Zhang-Jie Shi
DOI:10.1002/chem.201603805
日期:2016.12.5
Ir‐catalyzed sp2 C−Hamidation of aldehydes with various anilines as stoichiometric or catalytic directing groups was accomplished. A wide range of substrates were selectively amidated in good to excellent yields with broad functional group tolerance. The iridacycle complexes were isolated, characterized, and proved as key intermediates. Kinetic studies and Hammett plots provided detailed understandings
用各种苯胺作为化学计量或催化方向的基团,对醛进行了Ir催化的sp 2 CH酰胺化反应。以良好的产率和优异的产率选择性选择性地酰胺化各种底物,并具有宽泛的官能团耐受性。分离,表征并证明了iridacycle复合物是关键中间体。动力学研究和Hammett图提供了对这种酰胺化反应的详细了解。根据机理,证明了富电子的ArSO 2 N 3对于分子间sp 3 CH酰胺化有效。
Switchable Imine and Amine Synthesis Catalyzed by a Well-Defined Cobalt Complex
Switchable imine and amine synthesis catalyzed by a tripodal ligand-supported well-defined cobaltcomplex is presented herein. A large variety of primary alcohols and amines were selectively converted to imines or amines in good to excellent yields. It is discovered that the base plays a crucial role on the selectivity. A catalytic amount of base leads to the imine formation, while an excess loading
Proline‐Mediated Enantioselective Construction of Tetrahydropyridines<i>via</i>a Cascade Mannich‐Type/Intramolecular Cyclization Reaction
作者:Rong‐Gang Han、Yao Wang、Yu‐Ye Li、Peng‐Fei Xu
DOI:10.1002/adsc.200800253
日期:2008.7.7
A highly diastereo- and enantioselective synthesis of 2,3-disubstituted tetrahydropyridines was accomplished via a proline-mediated cascade Mannich-type/intramolecularcyclizationreaction from preformed N-PMP (p-methoxyphenyl) aldimines and inexpensive aqueous tetrahydro-2H-pyran-2,6-diol.
Tetrahydroquinolines and Benzazepines through Catalytic Diastereoselective Formal [4 + 2]-Cycloaddition Reactions between Donor–Acceptor Cyclopropenes and Imines
作者:Phong M. Truong、Michael D. Mandler、Peter Y. Zavalij、Michael P. Doyle
DOI:10.1021/ol401308d
日期:2013.7.5
Regio- and diastereoselective Lewisacidcatalyzedcycloadditionreactions between imines and donor–acceptor cyclopropenes generated from silyl-protected enoldiazoacetates provide direct access to stable cyclopropane-fused tetrahydroquinolines and, with cyclopropane ring opening under mild conditions, to 1H-benzazipine derivatives.
Asymmetric Petasis Borono‐Mannich Allylation Reactions Catalyzed by Chiral Biphenols
作者:Yao Jiang、Scott E. Schaus
DOI:10.1002/anie.201611332
日期:2017.2
Chiral biphenols catalyze the asymmetric Petasis borono‐Mannich allylation of aldehydes and amines through the use of a bench‐stable allyldioxaborolane. The reaction proceeds via a two‐step, one‐pot process and requires 2–8 mole % of 3,3′‐Ph2‐BINOL as the optimal catalyst. Under microwave heating the reaction affords chiral homoallylic amines in excellent yields (up to 99 %) and high enantioselectivies