Cu-catalyzed [2 + 2 + 1] cascade annulation of vinyl iodonium salts with elemental sulfur/selenium for the modular synthesis of thiophenes and selenophenes
作者:Yaxing Wu、Chao Wu、Fei Wang、Chao Chen
DOI:10.1039/d1nj05433c
日期:——
A [2 + 2 + 1] annulation protocol has been established for the modular synthesis of 2,4-disubstituted thiophenes/selenophenes, with excellent regioselectivity. The reactions have been catalyzed by copper salt with elemental sulfur and selenium serving as the chalcogen source. The mechanistic study has revealed that this process was initiated by a trisulfur radical anion using EPR.
Oxalyl Boronates Enable Modular Synthesis of Bioactive Imidazoles
作者:C. Frank Lee、Aleksandra Holownia、James M. Bennett、Jonathan M. Elkins、Jeffrey D. St. Denis、Shinya Adachi、Andrei K. Yudin
DOI:10.1002/anie.201611006
日期:2017.5.22
accessible through commercially available starting materials, enables a modular approach for the synthesis of imidazoles. A variety of aromatic, heteroaromatic, and alkyl carboxaldehydes were condensed with oxalyl boronates to afford substituted boryl imidazoles in a regiocontrolled fashion. Subsequent palladium-catalyzed cross-coupling with haloarenes furnished the desired trisubstituted imidazole scaffolds
A photocatalytic multi‐component radical relay reaction has been developed for the stereodivergent synthesis of both stereoisomers of α‐aminomethyl cinnamyl ethers. The radical relay reaction of hydroxylamine derivatives, enol ethers and alkenyl boronic acids in DMSO under white LEDs could lead to E‐isomers of α‐aminomethyl cinnamyl ethers. The E‐isomers could subsequently isomerize to less thermodynamically
hydroalkenylation of unsaturated aldehydes and ketones has been accomplished via synergistic HOMO and LUMO activation by means of manganese and iminium catalysis. The use of chiral organocatalysts could provide the corresponding products with moderate enantioselectivity.
不饱和醛和酮的选择性加氢烯基化是通过锰和亚胺催化的协同 HOMO 和 LUMO 活化来完成的。使用手性有机催化剂可以提供具有中等对映选择性的相应产物。
Manganese(I)‐Catalyzed Enantioselective C(sp<sup>2</sup>)−C(sp<sup>3</sup>) Bond‐Forming for the Synthesis of Skipped Dienes with Synergistic Aminocatalysis
synergistic catalytic strategy has addressed the great challenge in Mn(I)-catalyzed enantioselective C−C bond coupling. A variety of structurally diverse skipped 1,4-dienes are furnished in synthetically useful yields and good enantioselectivity. This strategy has also been applied for the totalsynthesis of the analogues of (−)-Blepharocalyxin D.
协同催化策略解决了 Mn(I) 催化的对映选择性 C−C 键偶联的巨大挑战。提供了多种结构多样的跳过 1,4-二烯,具有合成上有用的产率和良好的对映选择性。该策略也已应用于 (−)-Blepharocalyxin D 类似物的全合成。