Orientational Chirality,Its Asymmetric Control,and Computational Study

查看全文 作　　者：Shengzhou [1]Jin;Yu [1]Wang;Yao [2]Tang;Jia-Yin [1,3]Wang;Ting [1]Xu;Junyi [1]Pan;Sai [2]Zhang;Qiankai [2]Yuan;Anis Ur [2]Rahman;James [2]D.McDonald;Guo-Qiang [1]Wang;Shuhua [1]Li;Guigen [1,2]Li 机构地区：[1]School of Chemistry and Chemical Engineering,Nanjing University,Nanjing,210093,China;[2]Department of Chemistry and Biochemistry,Texas Tech University,Lubbock,TX 79409-1061,USA;[3]Continuous Flow Engineering Laboratory of National Petroleum and Chemical Industry,Changzhou University,Changzhou,Jiangsu 213164,China 出　　处：《Research》索引2023年第1期,共8页 基　　金：supportfrom the Robert A.Welch Foundation(D-1361-20210327,USA);from the National Natural Science Foundation ofChina(nos.22071102,91956110,22073043,and 21833002). 摘　　要：Orientational chirality was discovered and characterized by a C(sp)-C(sp3)axis-anchored chiral center and a remotely anchored blocker.X-ray structural analysis proved that orientatiomers are stabilized by through-space functional groups,making it possible for 1 R-or S-chiral center to exhibit 3 orientational isomers simply by rotating operations.A new model system was proposed,fundamentally different from the traditional Felkin-Ahn-type or Cram-type models.In these traditional models,chiral C(sp^(3))center and blocking C(sp^(3))carbons are connected adjacently,and there exist 6 energy barriers during rotating along the C(sp^(2))-C(sp^(3))axis.In comparison,the present orientational chirality model shows that a chiral C(sp)-C(sp^(3))carbon is remotely located from a blocking group.Thus,it is focused on the steric dialog between a chiral C(sp^(3))center and a remotely anchored functional group.There exist 3 energy barriers for either(R)-or(S)-C(sp)-C(sp^(3))stereogenicity in the new model.Chiral amide auxiliary was proven to be an excellent chiral auxiliary in controlling rotations of orientatiomers to give complete stereoselectivity.The asymmetric synthesis of individual orientatiomers was conducted via multistep synthesis by taking advantage of the Suzuki-Miyaura cross-coupling and Sonogashira coupling reactions.Density functional theory computational study presented optimized conformers and relative energies for individual orientatiomers.This discovery would be anticipated to result in a new stereochemistry topic and have a broad impact on chemical,biomedical,and material sciences in the future. 关 键 词：CHIRAL CHIRAL ROTATING