AP 甲硅烷基膦酸酯和森田-的Baylis-希尔曼乙酸盐(MBHAs)之间C键形成反应探索作为向医药相关β-carboxyphosphinic结构基序的通用的替代方案。使用31记录的不同取代的MBHA转化为次膦酸9或14的转化率P NMR光谱显示酯和腈衍生物之间的反应性差异出乎意料。这些动力学曲线和DFT计算支持了一种机械方案,其中可以从过渡态的“迟缓”解释观察到的差异。此外,我们提供的实验证据表明,由于最初的P-Michael加成而形成的烯醇不形成。基于拟议的机械情景结合DFT计算,对E / Z的解释提出了酯和腈之间的立体选择性差异。提出了由这种转变产生的合成机会,该机会涉及几种合成的反复变化的膦基结构单元的制备,而这些结构单元通过经典的P-Michael合成路线的访问并不简单。
AP 甲硅烷基膦酸酯和森田-的Baylis-希尔曼乙酸盐(MBHAs)之间C键形成反应探索作为向医药相关β-carboxyphosphinic结构基序的通用的替代方案。使用31记录的不同取代的MBHA转化为次膦酸9或14的转化率P NMR光谱显示酯和腈衍生物之间的反应性差异出乎意料。这些动力学曲线和DFT计算支持了一种机械方案,其中可以从过渡态的“迟缓”解释观察到的差异。此外,我们提供的实验证据表明,由于最初的P-Michael加成而形成的烯醇不形成。基于拟议的机械情景结合DFT计算,对E / Z的解释提出了酯和腈之间的立体选择性差异。提出了由这种转变产生的合成机会,该机会涉及几种合成的反复变化的膦基结构单元的制备,而这些结构单元通过经典的P-Michael合成路线的访问并不简单。
DMAP-Catalyzed [3 + 2] and [4 + 2] Cycloaddition Reactions between [60]Fullerene and Unmodified Morita–Baylis–Hillman Adducts in the Presence of Ac<sub>2</sub>O
作者:Hai-Tao Yang、Wen-Long Ren、Chun-Bao Miao、Chun-Ping Dong、Yang Yang、Hai-Tao Xi、Qi Meng、Yan Jiang、Xiao-Qiang Sun
DOI:10.1021/jo3025797
日期:2013.2.1
One-step DMAP-catalyzed [3 + 2] and [4 + 2] cycloaddition reactions between C60 and unmodified Morita–Baylis–Hillman adducts in the presence of Ac2O have been developed for the easy preparation of cyclopentene- and cyclohexene-fused [60]fullerene derivatives. When the MBH adducts bear an alkyl group, two different reaction pathways could be controlled selectively depending on the conditions.
On the development of a nucleophilic methylthiolation methodology
作者:Bernardo Basbaum Portinho de Puga Carvalho、Adriane Antonia Pereira Amaral、Pedro Pôssa de Castro、Fernanda Cerqueira Moreira Ferreira、Bruno Araújo Cautiero Horta、Giovanni Wilson Amarante
DOI:10.1039/d0ob01149e
日期:——
yields. The reactionmechanism was investigated through several control experiments, as well as by theoretical calculations employing Density Functional Theory. The results strongly support that a sulfurane and a sulfonium ylide appear as key intermediates and that a Pummerer type rearrangement is also crucial for the formation of this novel reagent. Furthermore, the methylthiolation mechanism is likely
Palladium-Catalyzed Asymmetric Construction of Vicinal Tertiary and All-Carbon Quaternary Stereocenters by Allylation of β-Ketocarbonyls with Morita-Baylis-Hillman Adducts
β‐ketocarbonyls with Morita–Baylis–Hillman adducts has been developed using a spiroketal‐based diphosphine (SKP) as the ligand, thus affording a range of densely functionalized products bearing vicinal tertiary and all‐carbon quaternary stereodyad in high selectivities. The utility of the protocol was demonstrated by the facilesynthesis of some complex molecules by simple product transformations.
An enantioselective radical alkylation of 4-alkyl-1,4-dihydropyridines with Morita–Baylis–Hillman (MBH) adducts has been reported. The SN2-type products are predominant. This reaction is enabled by dual photoredox/palladiumcatalysis. The alkylation products are provided in good yields with good regio- and enantioselectivity. The use of Ding’s spiroketal-based bis(phosphine) (SKP) ligand is crucial
已经报道了 4-烷基-1,4-二氢吡啶与 Morita-Baylis-Hillman (MBH) 加合物的对映选择性自由基烷基化。S N 2 型产品占主导地位。该反应是通过双光氧化还原/钯催化实现的。烷基化产物以良好的产率和良好的区域选择性和对映选择性提供。Ding 的基于螺缩酮的双(膦)(SKP)配体的使用对于实现令人满意的区域选择性和对映选择性至关重要。生成的 α,β-不饱和酯可以很容易地还原为合成有用的手性烯丙醇。