Catalytic Asymmetric Total Synthesis of (−)-Galanthamine and (−)-Lycoramine
作者:Lei Li、Qiao Yang、Yuan Wang、Yanxing Jia
DOI:10.1002/anie.201411338
日期:2015.5.18
conceptually new strategy featuring two metal‐catalyzed reactions as the key steps. A new method for the construction of 3,4‐fused benzofurans has been developed through a palladium‐catalyzed intramolecular Larock annulation reaction, which was successfully applied to the construction of the ABD tricyclic skeleton of 1 and 2. To achieve the asymmetric synthesis of 1 and 2, a ScIII/N,N′‐dioxide complex was used
(-)-加兰他敏(1)和(-)-lycoramine(2)的催化不对称全合成反应已通过采用概念上新颖的策略来实现,该策略以两个金属催化的反应为关键步骤。通过钯催化的分子内Larock环化反应,开发了一种3,4-稠合苯并呋喃的构建新方法,该方法已成功应用于1和2的ABD三环骨架的构建。为了实现1和2的不对称合成,Sc III / N,N'-二氧化物络合物被用来催化3-烷基取代的苯并呋喃酮向甲基乙烯基酮的对映选择性共轭加成反应,以构建手性季碳中心。
A Palladium-Catalyzed Regioselective Hydroesterification of Alkenylphenols to Lactones with Phenyl Formate as CO Source
作者:Haining Wang、Ben Dong、Yang Wang、Jingfu Li、Yian Shi
DOI:10.1021/ol403171p
日期:2014.1.3
An effective Pd(OAc)2-PPh3 catalyzed hydroesterification of alkenylphenols with phenyl formate as CO surrogate is described. A variety of lactones are obtained in generally high yields with high regioselectivities. In one case, 76% ee is obtained with a chiral ligand.
An organocatalytic asymmetric reaction of benzofuran-2(3H)-ones with naphthoquinones is disclosed. The current method provides a direct way to furnish arylation of benzofuran-2(3H)-ones in high yields with excellent enantioselectivities. A cooperative...
A highly enantioselective allylation of benzofuran-2(3H)-ones is achieved under Pd catalysis by taking full advantage of the structural modularity of ion-paired chiral ligands.
Enantioselective TADMAP-Catalyzed Carboxyl Migration Reactions for the Synthesis of Stereogenic Quaternary Carbon
作者:Scott A. Shaw、Pedro Aleman、Justin Christy、Jeff W. Kampf、Porino Va、Edwin Vedejs
DOI:10.1021/ja056150x
日期:2006.1.1
efficient and are used to prepare chiral lactams (23) and lactones (30) containing a quaternary asymmetric carbon. TADMAP-catalyzed carboxyl migrations in the indole series are relatively slow and proceed with inconsistent enantioselectivity. Modeling studies (B3LYP/6-31G*) have been used in qualitative correlations of catalyst conformation, reactivity, and enantioselectivity.