The spiro pyrrolidin-3,3'-oxindole core is a privileged skeleton that is found in many natural products and biologically active molecules. For its construction, the [3＋2] cycloaddition of 2π component 3-alkenyl-oxindoles with 3π component azomethine ylides is one of the most effective strategies. Since the pioneering work of Gong and co-workers, great effort has been devoted to the development of asymmetric [3＋2] cycloadditions with azomethine ylides as the dipole synthon, and impressive progress has been achieved. In contrast, there is no report about higher-order [8＋2] cycloaddition of 3-alkenyl-oxindoles with azaheptafulvenes as the 8π dipole synthons, which is an effective way to build cycloheptatriene-fused pyrrolidin-3,3'-oxindole derivatives with three contiguous stereocenters, including a spiro-quaternary chiral carbon atom. Herein, the azaheptafulvenes is developed as a new dipole synthon with 3-alkenyl-oxindoles to construct pyrrolidin-3,3'-oxindoles derivatives for the first time. In the presence of 1 mol% of chiral N,N'-dioxide L6-Ni(II) complex, the asymmetric [8＋2] cycloaddition performs well, affording functionalized cycloheptriene-fused pyrrolidin-3,3'-oxindoles derivatives in excellent yields (90%～99%), diastereoselectivities (up to 97∶3 dr), and enantioselectivities (92%～99% ee) under mild conditions. A representative procedure for the asymmetric [8＋2] cycloaddition is as follows: to a test tube, the catalyst solution (1 mol% , in THF) was added, and the THF was evaporated by oil pump. N-Boc-3-alkenyl-oxindole 2a and 0.5 mL of CH 2 Cl 2 were added sequentially under air (N 2 atmosphere is not necessary). The reaction solution was stirred at 35 ℃ for 0.5 h, then the 8π component azaheptafulvene 1a (1.05 equiv.) was added. The mixture continued stirring at 35 ℃ until N-Boc-3-alkenyl-oxindole 2a was consumed (detected by TLC). Finally, the corresponding product 3a was purified by flash chromatography on basic Al 2 O 3 [V(petroleum)/V(CH 2 Cl 2)/V(EtOAc)＝8∶8∶1].

1,2,3-Trizaole derivatives have been widely used in the fields of medicine pesticide and materials. Thus, much attention has been paid to the synthesis of various 1,2,3-trizaole derivatives. However, the transformation of function group at N(1) position of 1,2,3-triazole derivatives was less studied. In this paper, in the presence of base and using copper salt as the catalyst, the sulfonyl group of 1,2,3-triazole derivatives could be transformed to other function groups in a "one-pot two-steps" manner, including benzyl, substituted benzyl, halide substituted alkyl or alkyl groups. This method exhibited mild reaction conditions and simple operation. Meanwhile, based on the captured reaction intermediate, the reaction mechanism was also proposed.

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3-Cyanomethyl oxoindoles are a kind of important drug intermediates, which can be used to synthesize horsfiline, esermethole and physostigmine and other natural products via the conversion of cyano functional groups. A domino Heck/cyanation reaction in aqueous was developed to afford 3-cyanomethyl oxoindole compounds. This method, using green medium water instead of organic solvents, without any basic additives, provided a green and efficient new procedure for the synthesis of 3-cyanomethyl oxoindoles.