通过富勒烯C60与肌氨酸和有机醛化合物的1,3-偶极环加成反应,获得了九种含不同有机功能基团的C60吡咯烷衍生物1~9,用^1HNMR,^13CNMR,FTIR,UV—vis和FAB-MS进行了结构表征:利用皮秒激光光源,采用z扫描技术测定了分子的三阶非线性超极化率γ(3),结果显示:化合物3γ(3)=4.14×10^-33 esu)具有最大的三阶非线性光学系数,说明增加噻吩共轭链的长度,使三阶非线性活性增加;对具有相同共轭链的C60-噻吩吡咯烷衍生物(2,5,1和4),吸电子取代基减小了三阶光学非线性活性,给电子基增大了三阶光学非线性活性;同时发现喹啉环2-位键联(7)比4-位(8)有更好的三阶光学非线性活性.
A series of azomethine ylides were prepared through the reaction between the different substituted conjugated aldehydes and sarcosine. Further 1,3-dipolar cycloaddition of these azomethine ylides to C60 gave a series of new fulleropyrrolidine derivatives 1~9. The molecular structures were identified and characterized by ^1H NMR, ^13C NMR, FTIR, UV-vis and FAB-MS spcctra. The third-order nonlinear optical hyperpolarizabilities γ(3) were obtained under picosecond laser by z-scan technique. It was found that the γ(3) value of 3 (4.14× 10^-33 esu) is the largest which indicates that the γ(3) values become larger with the increasing length of nT. We also found that different substituents at the a position of the thiophene rings (2, 5, 1 and 4), different position of N atom of quinoline (7 and 8) and different kinds of conjugate chain have different effects on the nonlinear optical properties of fulleropyrrolidine dyads.