carbonates (VECs) with diols has been developed. By using cooperative catalysts of the chiral palladium complex and triethylborane in mild conditions, the process gave monoetherified and bisetherified polyglycol derivatives with tetrasubstituted stereocenters in high yields with complete regioselectivities and high levels of enantio- and diastereoselectivities.
Chiral Bidentate Phosphoramidite-Pd Catalyzed Asymmetric Decarboxylative Dipolar Cycloaddition for Multistereogenic Tetrahydrofurans with Cyclic <i>N</i>-Sulfonyl Ketimine Moieties
作者:Hao-Peng Lv、Xiao-Peng Yang、Bai-Lin Wang、Hao-Di Yang、Xing-Wang Wang、Zheng Wang
DOI:10.1021/acs.orglett.1c01411
日期:2021.6.18
An asymmetric [3 + 2] cycloaddition of vinyl ethylenecarbonates (VECs) and (E)-3-arylvinyl substituted benzo[d] isothiazole 1,1-dioxides has been developed using the Pd complex of a bidentate phosphoramidite (Me-BIPAM) as the catalyst, providing a wide variety of chiral multistereogenic vinyltetrahydrofurans in good yields with excellent diastereo- and enantioselectivities (up to >20:1 dr, 99% ee)
Divergent synthesis of N-heterocycles by Pd-catalyzed controllable cyclization of vinylethylene carbonates
作者:Yuwen Yang、Weibo Yang
DOI:10.1039/c8cc06945j
日期:——
Here, we report a palladium-catalyzed controllable cyclization of vinyl ethylene carbonates that proceeds through formal migration [2+3] and [5+2] cycloadditions, respectively, under mild conditions.
Here, we report the discovery of such a phenomenon in nickel/copper-co-catalyzed divergent allylic alkylation of vinyl epoxides and aziridines using alkynes. Under otherwise identical conditions, the use of either strong bisphosphine ligands or hemilabile P,N-ligands leads to bimolecular allylicalkynylation or trimolecular dienyne formation, respectively. DFT calculations provide key insights for
tertiary C-O bond via asymmetric allylicsubstitution of racemic vinylethylene carbonates with water and alcohols has been developed. Under the cooperative catalysis system of an in situ generated chiral palladium complex and boron reagent in mild conditions, the process allowed rapid access to valuable tertiary alcohols and ethers in high yields with complete regioselectivities and high enantioselectivities
已经开发了一种通过外消旋乙烯基碳酸亚乙酯与水和醇的不对称烯丙基取代对映选择性构建叔 CO 键的有效方法。在温和条件下原位生成的手性钯配合物和硼试剂的协同催化系统下,该过程允许以高产率快速获得有价值的叔醇和醚,具有完整的区域选择性和高对映选择性。该协议代表了与作为氧供体的水直接对映选择性形成三级 CO 键的第一个例子。该过程的合成效用已通过将产品加工成生物相关制剂的关键中间体来证明,