Diastereodivergent Asymmetric [4+2] Cycloaddition of In Situ Generated ortho-Quinone Methides and Allenyl Ketones Enabled by Chiral Phosphoric Acid Catalysis Guosong Shen, Faqian He, Wansen Xie, Huanchao Gu, and Xiaoyu Yang* ACS Catal.2023, 13, 12472–12480 https://doi.org/10.1021/acscatal.3...
近日,美国斯坦福大学Noah Z. Burns课题组开发了一种新型的环丁二烯试剂(二乙基二氮杂双环己烯二甲酸酯),其可与一系列缺电子烯烃进行分子间的[4+2]环加成反应。同时,通过dipiperamide G的三步全合成以及产物的后期衍生化,进一步证明了反应的实用性。相关研究成果发表在J. Am. Chem. Soc.上(DOI: 10.1021/jacs.3...
在-10 ℃低温下反应,反应能以96%的高产率和96:4的高对映选择性得到理想产物3aa(entry 6);2)通过entries 8-10发现,第一代铁催化剂不适用于含苯基的支链二烯烃1b和直链二烯烃2a间的反应;3)进一步开发第二代含双二氢异喹啉骨架的手性二亚胺铁催化剂,通过逐步增大骨架和侧臂的刚性(entries 11-15),发现催化...
该反应还具有高模块化、原子经济性、广泛的底物范围、无金属条件、简单的催化剂和操作等特点。 参考资料:Regio- and Diaseteroselective Synthesis of Polysubstituted Piperidines Enabled by Boronyl Radical-Catalyzed (4+2) Cycloaddition. ACIE, DOI:...
论文信息:Enantio-, Diastereo- and Regioselective Synthesis of Chiral Cyclic and Acyclic gem-Difluoromethylenes by Palladium-Catalyzed [4+2] CycloadditionHiroto Uno, Koki Kawai, Taichi Araki, Motoo Shiro and Norio Shibata*Angew. Chem. Int. Ed.DOI: 10.1002/anie.202117635...
Tandem Diels–Alder reactions are frequently used in the construction of polycyclic ring systems in complex organic compounds. Unlike the many Diels−Alderases (DAases) that catalyse a single cycloaddition, enzymes for multiple Diels–Alder reactions a
中国科学院上海有机化学研究所研究员刘文、潘李锋,与美国加州大学洛杉矶分校化学系Ken. N. Houk实验室合作,在Nature Chemistry上,发表了题为A cyclase that catalyses competing 2+2 and 4+2cycloadditions的研究论文。该研究发现了可以催化竞争性的2+2及4+2环加成反应的新型环加成酶,并基于计算辅助的定向进化设计...
A Metal-Free Cyclobutadiene Reagent for Intermolecular [4 + 2] Cycloadditions Benjamin R. Boswell, Carl M. F. Mansson, Gabrielle E. Cabrera, Calvin R. Hansen, Allen G. Oliver, Noah Z. Burns J. Am. Chem. Soc.DOI: 10.1021/jacs.3c01591 ...
Enantio-, Diastereo- and Regioselective Synthesis of Chiral Cyclic and Acyclic gem-Difluoromethylenes by Palladium-Catalyzed [4+2] Cycloaddition Hiroto Uno, Koki Kawai, Taichi Araki, Motoo Shiro and Norio Shibata* Angew. Chem. Int. Ed. DOI: 10.1002/anie.202117635...
Catalytic Enantioselective [4+2] Cycloadditions of Salicylaldehyde Acetals with Enol Ethers Xiaojun Hu, Zhengbo Zhu, Zhongzheng Li, Alafate Adili, Minami Odagi, Khalil A. Abboud, Daniel Seidel Angew. Chem. Int. Ed. DOI: 10.1002/anie.202315759 ...