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 α 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.

Key words: z-scan, third-order nonlinear optical hyperpolarizability, fulleropyrrolidine