Enantioselective Synthesis of Distorted π‐Extended Chiral Triptycenes Consisting of Three Distinct Aromatic Rings by Rhodium‐Catalyzed [2+2+2] Cycloaddition
作者:Yukimasa Aida、Yu Shibata、Ken Tanaka
DOI:10.1002/chem.201905519
日期:2020.3.9
The enantioselective synthesis of distorted π-extended chiral triptycenes, consisting of three distinct aromatic rings, has been achieved with high ee value of 87 % by the cationic rhodium(I)/segphos complex-catalyzed enantioselective [2+2+2] cycloaddition of 2,2'-di(prop-1-yn-1-yl)-5,5'-bis(trifluoromethyl)-1,1'-biphenyl with 6-methoxy-1,2-dihydronaphthalene followed by the diastereoselective Diels-Alder
阳离子铑(I)/ segphos络合物催化的对映体选择性[2 + 2 + 2]环加成反应可实现由三个不同的芳环组成的扭曲的π延伸手性三萜烯的对映体选择性合成,其ee值高达87%。 2,2'-二(prop-1-yn-1-yl)-5,5'-双(三氟甲基)-1,1'-联苯与6-甲氧基-1,2-二氢萘,然后进行非对映选择性Diels- der木反应和芳构化。还通过CO键裂解合成了脱甲氧基衍生物。在该合成中,使用缺电子的二炔和富电子的烯烃对于抑制不希望的消除应力的碳正离子重排和稳定扭曲的三并茂结构至关重要。