Intramolecular annulation of aromatic rings with N-sulfonyl 1,2,3-triazoles: divergent synthesis of 3-methylene-2,3-dihydrobenzofurans and 3-methylene-2,3-dihydroindoles
作者:Xiang-Ying Tang、Yong-Sheng Zhang、Lv He、Yin Wei、Min Shi
DOI:10.1039/c4cc08343a
日期:——
The controllable synthesis of 3-methylene-2,3-dihydrobenzofurans2and 3-methylene-2,3-dihydroindoles5has been developed via cycloisomerization of N/O-tethered aryltriazoles.
The regioselective sulfenylation of N-sulfonylanilines with phthalimidesulfenyl chloride afforded the precursors of transient o-iminothioquinones obtained very easily under mild reaction conditions. These species are efficient electron-poor dienes able to react with several electron-rich alkenes to give, with complete control of the regiochemistry, benzo[b][1,4]thiazine cycloadducts.
Phosphane-Catalyzed Umpolung Addition Reaction of Nucleophiles to Ethyl 2-Methyl-2,3-butadienoate
作者:Xiao-Yang Guan、Yin Wei、Min Shi
DOI:10.1002/ejoc.201100095
日期:2011.5
phosphane-catalyzed umpolung addition of various nucleophiles to ethyl 2-methyl-2,3-butadienoate is described. Oxygen, nitrogen, and carbon nucleophiles smoothly reacted with ethyl 2-methyl-2,3-butadienoate to give the corresponding umpolung addition products in good to excellent yields by a similar reaction mechanism. For sulfur nucleophiles, the addition reactions with ethyl 2-methyl-2,3-butadienoate proceeded
one-pot synthesis of 3,3-disubstituted-2-dihydropyridinones from N-(arylsulfonyl)acrylamides and 1,3-dicarbonyl compounds. In this case, a silver-catalyzed radical cascade process involving the sequential formation of two new C-C bonds and one C-N bond, a formal 1,4-aryl migration, and desulfonylation of the starting material explains the regioselective formation of densely functionalized heterocycles
在 N-(芳基磺酰基)丙烯酰胺的双键上添加各种自由基可以通过酰胺基自由基中间体 2 触发环化/芳基迁移/脱磺酰化级联反应。在此,我们展示了这些中间体在随后的 CC 和 CX 键中的合成效用 -形成事件以快速建立分子复杂性。首先,我们描述了一种区域选择性一锅法合成 CF3-、SCF3-、Ph2(O)P- 和 N3-indolo[2,1-a]isoquinolin-6(5H)-ones 从 N-[(2 -乙炔基)芳基磺酰基]丙烯酰胺通过多步自由基反应级联。该过程包括一锅法形成四个新键(一个 CX、两个 CC 和一个 CN)、正式的 1,4-芳基迁移和起始材料的脱磺酰化。其次,我们提出了从 N-(芳基磺酰基)丙烯酰胺和 1,3-二羰基化合物。在这种情况下,银催化的自由基级联过程包括连续形成两个新的 CC 键和一个 CN 键、正式的 1,4-芳基迁移和起始材料的脱磺酰化,解释了在直截了当的方式。对
Broad scope gold(<scp>i</scp>)-catalysed polyenyne cyclisations for the formation of up to four carbon–carbon bonds
作者:Zhouting Rong、Antonio M. Echavarren
DOI:10.1039/c7ob00235a
日期:——
The polycyclisation of polyenynes catalyzed by gold(I) has been extended for the first time to the simultaneous formation of up to four carbon–carbon bonds, leading to steroid-like molecules with high stereoselectivity in a single step with low catalyst loadings. In addition to terminal alkynes, bromoalkynes can also be used as initiators of polyene cyclisations, giving rise to synthetically useful