Diastereoselective Pd(II)-Catalyzed sp3 C-H Arylation Followed by Ring Opening of Cyclopropanecarboxamides: Construction of anti β-Acyloxy Carboxamide Derivatives
Diastereoselective Pd(II)-Catalyzed sp3 C-H Arylation Followed by Ring Opening of Cyclopropanecarboxamides: Construction of anti β-Acyloxy Carboxamide Derivatives
复制标题
DOI：
10.1021/acs.joc.6b01635
复制
发表时间：
2016-10-07
影响因子：
3.6
通讯作者：
Babu, Srinivasarao Arulananda
中科院分区：
文献类型：
--
作者：
Gopalakrishnan, Bojan;Mohan, Sruthi;Babu, Srinivasarao Arulananda
非对映选择性Pd（OAc）（2）-催化的、双齿配体-导向的sp（3）C-H活化/芳基化，然后环丙烷甲酰胺开环，其由环丙烷甲酰氯和双齿配体（例如，8-氨基喹啉和2-（甲硫基）苯胺）。在Pd（OAc）（2）催化剂、AgOAc和AcOH存在下，用过量的芳基碘处理各种环丙烷甲酰胺，直接得到相应的多个β-C-H芳基化开链甲酰胺（反β-酰氧基酰胺）。这种方法导致了几个反β-酰氧基酰胺的建设，具有邻位立体中心与高度的立体控制，形成一个新的C-O键和三个新的C-C键。基于几个对照实验，提出了由Pd催化的双齿配体引导的β-C-H芳基化和环丙烷甲酰胺的开环形成多个β-C-H芳基化开链甲酰胺的合理机制。所观察到的非对映选择性和反立体化学的β-酰氧基酰胺的基础上确定的代表性β-酰氧基酰胺的X-射线结构分析。
The diastereoselective Pd(OAc)(2)-catalyzed, bidentate ligand-directed sp(3) C-H activation/arylation followed by ring opening of cyclopropanecarboxamides, which were assembled from cyclopropanecarbonyl chlorides and bidentate ligands (e.g., 8-aminoquinoline and 2-(methylthio)aniline), has been investigated. The treatment of various cyclopropanecarboxamides with excess amounts of aryl iodides in the presence of the Pd(OAc)(2) catalyst, AgOAc and AcOH directly afforded the corresponding multiple beta-C-H arylated open-chain carboxamides (anti beta-acyloxy amides). This method has led to the construction of several anti beta-acyloxy amides that possess vicinal stereocenters with a high degree of stereocontrol with the formation of a new C-O bond and three new C-C bonds. A plausible mechanism for the formation of multiple beta-C-H arylated open-chain carboxamides from the Pd-catalyzed, bidentate ligand-directed beta-C-H arylation and the ring opening of cyclopropanecarboxamides is proposed based on several control experiments. The observed diastereoselectivity and anti stereochemistry of the beta-acyloxy amides were ascertained based on X-ray structural analysis of representative beta-acyloxy amides.