Crescent aromatic oligothioamides as highly selective receptors for copper(Ⅱ) ion  

作　　者：HE LuTao JIANG Qian GAO RongZhao YANG XinShi FENG Wen LUO ShunZhong YANG YanQiu YANG Liang YUAN LiHua 

机构地区：[1]Key Laboratory for Radiation Physics and Technology of Ministry of Education,College of Chemistry,Institute of Nuclear Science and Technology,Sichuan University [2]Institute of Nuclear Physics and Chemistry,China Academy of Engineering Physics

出　　处：《Science China Chemistry》2014年第9期1246-1256,共11页中国科学（化学英文版）

基　　金：supported by the National Natural Science Foundation of China(21172158);the Joint Fund of National Natural Science Foundation of China and the China Academy of Engineering Physics(11076018);the Doctoral Program of the Ministry of Education of China(20130181110023);the National Science Foundation for Fostering Talents in Basic Research of the National Natural Science Foundation of China(J1210004,J1103315);Open Project of State Key Laboratory of Supramolecular Structure and Materials(SKLSSM201408);Open Project of State Key Laboratory of Structural Chemistry(20140013)

摘　　要：A series of crescent aromatic oligothioamides(4, 6, 8, 15, and 18) bearing different number of sulfur atoms were designed and synthesized via thionation of their corresponding aromatic oligoamides(3, 5, and 7) using Lawesson's reagent. The X-ray structure of a trimeric analogue(13) revealed the presence of intramolecular three-center hydrogen bonds that are responsible for the rigidification of the molecular backbone. The extraction by these novel receptors toward some representative heavy metal cations(Zn2+, Cd2+, Co2+, Ni2+, Pb2+, and Cu2+) and alkali and alkaline earth metal cations(Li+, Na+, K+, Rb+, Cs+, Ca2+, and Sr2+) demonstrated high efficiency(83.5%–96.4%) and superior selectivity for Cu2+ over other selected metal cations. Particularly, the extractability was correlated to both the number of sulfur atoms and orientation of thiocarbonyl groups as revealed in the order: 6 > 4 > 18 > 15. This is in stark contrast to the oligoamides that only gave much lower extractability(5.9%–16.4%), suggestive of the importance of replacement of carbonyl oxygen atoms with sulfur atoms in the extraction of Cu2+. The complexation behavior of 4, 6, and 8 with Cu2+ was also examined by UV-Vis and NMR techniques.A series of crescent aromatic oligothioamides （4, 6, 8, 15, and 18） bearing different number of sulfur atoms were designed and synthesized via thionation of their corresponding aromatic oligoamides （3, 5, and 7） using Lawesson＇s reagent. The X-ray structure of a trimeric analogue （13） revealed the presence of intramolecular three-center hydrogen bonds that are responsible for the rigidification of the molecular backbone. The extraction by these novel receptors toward some representative heavy metal cations （Zn^2＋, Cd^2＋, Co^2＋, Ni^2＋, Pb^2＋, and Cu^2＋） and alkali and alkaline earth metal cations （Li^＋, Na^＋, K^＋, Rb^＋, Cs^＋, Ca2^＋, and Sr^2＋） demonstrated high efficiency （83.5%-96.4%） and superior selectivity for Cu^2＋ over other selected metal cations. Particularly, the extractability was correlated to both the number of sulfur atoms and orientation of thiocarbonyl groups as revealed in the order： 6 〉 4 〉 18 〉 15. This is in stark contrast to the oligoamides that only gave much lower extractability （5.9%-16.4%）, suggestive of the importance of replacement of carbonyl oxygen atoms with sulfur atoms in the extraction of Cu^2＋. The complexation behavior of 4, 6, and 8 with Cu^2＋ was also examined by UV-Vis and NMR techniques.

关 键 词：aromatic oligothioamide hydrogen bonding copper selective extraction cation receptor 

分 类 号：O614.121[理学—无机化学]