Copper-Catalyzed Asymmetric Conjugate Addition of Alkenyl- and Alkylalanes to α,β-Unsaturated Lactams
作者:Pierre Cottet、Daniel Müller、Alexandre Alexakis
DOI:10.1021/ol303505k
日期:2013.2.15
lactams via a copper-catalyzed asymmetric 1,4-addition of the corresponding alanes. Moderate to good yields and good to excellent enantioselectivities are achieved by using a combination of the very cheap copper(II) naphthenate and a readily available phosphine amine ligand. The creation of an all-carbon quaternarystereogeniccenter, via Michael addition to a trisubstitutedconjugated lactam, is also
The totalsynthesis of two polycyclic norcembranoid diterpenoids is described. Key transformations developed for the synthesis are an intramolecular double Michael addition to construct the [7,6,5,5] tetracyclic skeleton, a Lewis acid/Brønsted acid mediated transannular oxa-Michael addition to introduce the strained ether bridge linking two quaternary carbon atoms, and bio-inspired conversion of sinulochmodin
描述了两种多环去甲松香二萜的全合成。为合成开发的关键转化是分子内双迈克尔加成以构建[7,6,5,5]四环骨架,路易斯酸/布朗斯台德酸介导的跨环氧杂-迈克尔加成以引入连接两个季碳原子的应变醚桥,以及将 Sinulochmodin C 转化为 scabrolide A。
Copper-Catalyzed Asymmetric 1,4-Addition of Alkenyl Alanes to <i>N</i>-Substituted-2-3-dehydro-4-piperidones
作者:Daniel Müller、Alexandre Alexakis
DOI:10.1021/ol3004436
日期:2012.4.6
Readily available vinyl alanes are used in the Cu-catalyzed asymmetric conjugate addition reaction to N-substituted-2-3-dehydro-4-piperidones. The enhanced reactivity of recently developed and easily prepared phosphine amine ligands in combination with inexpensive Cu(II)naphtenate (CuNp) allows the introduction of a great variety of alkenyl, alkyl, and aryl aluminums in high enantioselectivity.