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An unprecedented chiral secondary amine-catalyzed [3 + 3] annulation of isatin N,N'-cyclic azomethine imines with α,β-unsaturated aldehydes was developed. This strategy allowed the construction of structurally novel spiro N-heterocyclic oxindole derivatives in good yields (up to 91%) and good to excellent enantioselectivities (up to >99% ee), albeit with modest diastereoselectivities (up to 3.1:1 dr).

A novel 2,3-indole-diene synthon was designed and synthesized, and was first applied to a stereoselective inverse-electron-demand Diels–Alder reaction to construct tetrahydrocarbazoles. In the presence of chiral secondary amines, a variety of enantioenriched, multifunctionalized tetrahydrocarbazole derivatives were obtained in good yields (up to 83%) with excellent stereoselectivities (up to >20 : 1 dr, 98% ee).

An amine-catalyzed asymmetric formal aza [3 + 3] cycloaddition of α,β-unsaturated aldehydes with N-Ts ketimines derived from both acyclic and cyclic ketones was developed, which was followed by an oxidation to afford chiral piperidine derivatives in good yields and excellent enantioselectivities (up to 99% ee). In addition, the corresponding cycloadduct piperidin-2-ols can be easily transformed to indolyl substituted chiral piperidine derivatives in good yields and excellent diastereoselectivities (>20:1) via Friedel-Crafts alkylation of indole in the presence of BF3·Et2O.

The populations of np forbidden transition states for two-step excitation of Na atom have been obtained by appling the static field of strength 167 V/cm. We have obtained lifetimes of np(n = 19-23) states by the method of delaying ionization in pulsed electric field, and have compared the calculation values with the measured data. The influence of applied fields and environmental radiation on the determination of the lifetimes of the highly excited states were discussed.