Palladium-Catalyzed Diastereoselective Coupling of Propargylic Oxiranes with Terminal Alkynes
摘要:
A diastereoselective coupling of propargylic oxiranes with terminal alkynes has been developed with use of a palladium catalyst. The stereochemistries of the resulting 4-alkynyl-substituted 2,3-allenols have been altered depending on the palladium catalyst. An optically active anti-substituted allene was synthesized from the reaction of an enantiomerically enriched propargylic oxirane without loss of chirality.
Synthesis of allenic diols by samarium diiodide-promoted coupling between alkynyloxiranes and ketones
作者:JoséM. Aurrecoechea、Eva Alonso、Mónica Solay
DOI:10.1016/s0040-4020(98)00110-0
日期:1998.4
The SmI2-mediated reductive coupling between alkynyloxiranes and ketones provides a new route to 2,3-pentadiene-1,5-diols. The preferred stereochemistry observed in the coupling products is the result of the new CC bond forming anti with respect to the opening epoxide ring. Yields and diastereoselectivities are dependent on the alkynyloxirane substitution pattern.
Stereoselective Synthesis of<i>syn</i>-Configured α-Allenols by Rhodium-Catalyzed Reaction of Alkynyl Oxiranes with Arylboronic Acids
作者:Tomoya Miura、Masahiko Shimada、Paula de Mendoza、Carl Deutsch、Norbert Krause、Masahiro Murakami
DOI:10.1021/jo900987w
日期:2009.8.21
A rhodium-catalyzedreaction of alkynyloxiranes with arylboronicacids affords syn-configured α-allenols with high diastereoselectivity. The reaction is initiated by addition of an arylrhodium(I) species onto the alkyne moiety of the alkynyloxirane. The resulting alkenylrhodium(I) intermediate undergoes β-oxygen elimination to open the oxirane ring in a syn-selective fashion. Protonolysis of the
Highly Stereoselective and Scalable Synthesis of <i>trans</i>-Fused Octahydrocyclohepta[<i>b</i>]pyrrol-4(1<i>H</i>)-ones via the Aza-Cope–Mannich Rearrangement in Racemic and Enantiopure Forms
作者:Dmitry S. Belov、Evgeny R. Lukyanenko、Alexander V. Kurkin、Marina A. Yurovskaya
DOI:10.1021/jo301762a
日期:2012.11.16
We have developed an efficient and stereoselective route to trans-fused octahydrocyclohepta[b]pyrrol-4(1H)-ones. The key features of our synthesis include the regioselective epoxide ring-opening of alkynyl oxiranes and a stereoselective aza-Cope–Mannich reaction. The target compounds were prepared in 3–6 steps from commercially available starting materials (61–75% overall yield) with minimal chromatographic
我们已经开发了一种有效的立体选择途径来合成反式八氢环庚[ b ]吡咯-4(1 H)-。我们合成的关键特征包括炔基肟基的区域选择性环氧化物开环和立体选择性aza-Cope-Mannich反应。目标化合物是从市售起始原料(总产率为61-75%)中以3–6步制备的,且色谱纯化最少。我们设计了一种立体选择性的路线,使用Shi环氧化或(R)-1-苯基乙胺作为手性来源来靶向化合物。
Synthesis of non-natural l-alanine derivatives using the aza-Cope–Mannich reaction
作者:Nina K. Ratmanova、Dmitry S. Belov、Ivan A. Andreev、Alexander V. Kurkin
DOI:10.1016/j.tetasy.2014.01.011
日期:2014.3
l-alanine derived trans-octahydrocyclohepta[b]pyrroles were synthesized with high enantiomeric purity using the aza-Cope–Mannichreaction. The study showed that the conditions of the aza-Cope–Mannichreaction and metal catalysed cyclization are mild enough to be applied to the synthesis of molecules with stereocenters, which are prone to racemization. We believe that these compounds will be of interest
使用aza-Cope-Mannich反应以高对映体纯度合成了非天然的l-丙氨酸衍生的反-八氢环庚七[ b ]吡咯。研究表明,氮杂-Cope-Mannich反应和金属催化的环化反应条件温和,足以用于合成具有立体中心且易于消旋的分子。我们相信,这些化合物将是药物化学家感兴趣的。
Stereoselective samarium diiodide-promoted intermolecular coupling of alkynyloxiranes with ketones. synthesis of 2,3-pentadiene-1,5-diols
作者:JoséM. Aurrecoechea、Mónica Solay
DOI:10.1016/0040-4039(95)00254-a
日期:1995.4
In the presence of samarium diiodide (SmI2), alkynyloxiranes undergo an efficient reductive coupling with ketones to afford 2,3-pentadiene-1,5-diols. The isolated yields are high and the stereoselectivity of the process ranges from moderate to very high. The stereochemistry of the major product of the reaction is the result of the new CC bond forming anti with respect to the opening epoxide ring.