通过使用胍-铜催化剂,由外消旋烯丙基溴对映体合成手性环状烯丙基硼酸酯。获得的烯丙基硼酸酯具有高的γ/α区域选择性(高达99:1)和对映选择性(高达99%ee),并且可以进一步转化为多种功能化的烯丙基化合物,而不会降低光学纯度。实验和DFT机理研究支持单齿胍-铜(I)配合物催化的S N 2'硼化过程,该过程通过特殊的直接对映体转化机理进行。
通过使用胍-铜催化剂,由外消旋烯丙基溴对映体合成手性环状烯丙基硼酸酯。获得的烯丙基硼酸酯具有高的γ/α区域选择性(高达99:1)和对映选择性(高达99%ee),并且可以进一步转化为多种功能化的烯丙基化合物,而不会降低光学纯度。实验和DFT机理研究支持单齿胍-铜(I)配合物催化的S N 2'硼化过程,该过程通过特殊的直接对映体转化机理进行。
Copper-Catalyzed Asymmetric Allylic Alkylation of Racemic Cyclic Substrates: Application of Dynamic Kinetic Asymmetric Transformation (DYKAT)
作者:Jean-Baptiste Langlois、Alexandre Alexakis
DOI:10.1002/adsc.200900790
日期:2010.2.15
The copper-catalyzedasymmetricallylicalkylation (AAA) is of great interest in organic synthesis. This reaction was extensively studied using a broad range of substrates, ligands and organometallic reagents. However, the use of racemic substrates was still limited. Although some processes of kinetic resolution are reported in the literature, no examples of quantitative deracemization are described
A study of Heck cyclization reactions to form phenanthridine ring systems
作者:Lauren R. Donaldson、David Haigh、Alison N. Hulme
DOI:10.1016/j.tet.2008.02.044
日期:2008.5
survey of conditions for the palladiumcatalyzed intramolecular Heck cyclization of protected amines has shown that the Herrmann–Beller palladacycle can be exploited under ‘cationic’ conditions to provide a robust and rapid route (<2 h) to the synthesis of single double bond isomer phenanthridines in excellent yield (76–99%). In addition, the same cyclization can be performed under ‘neutral’ conditions
对钯催化的受保护胺的分子内Heck环化条件的研究表明,可以在“阳离子”条件下利用Herrmann-Beller palladacycle,以提供可靠且快速的路线(<2小时)来合成单双键异构体菲啶的收率极高(76–99%)。此外,可以在“中性”条件下进行相同的环化反应,以提供具有双键异构体特征的菲啶,适用于基于多样性的应用。我们还表明,高反应性(t Bu 3 P)2 Pd催化剂可在低温(≤50°C)下诱导环化,与“中性”条件产生相似的结果,并为敏感底物提供替代途径。
Diastereoselective alkylation guided by electrophile-nucleophile .pi.-interactions
作者:John M. McIntosh、Randy K. Leavitt、Pratibha Mishra、Kenneth C. Cassidy、John E. Drake、R. Chadha
DOI:10.1021/jo00244a019
日期:1988.4
Crossley; Le Sueur, Journal of the Chemical Society, 1902, vol. 81, p. 833