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An interesting β-isoquinidine catalyzed divergent reaction was developed to produce either spirocyclopentene oxindoles, spirocyclopentadiene oxindoles or bisoxindoles in a high enantioselective fashion. The utility of this protocol was demonstrated by the versatile transformations of the products. This work not only represents the first highly stereoselective intermolecular catalytic asymmetric allylic alkylation reaction between two isatin-derived MBH carbonate molecules but also constitutes a rare example of isatin-derived MBH carbonate-based enantioselective and α-regioselective [3+2] cycloaddition reactions.

A novel Tin-functionalized integrated rubber of styrene-isoprene-butadiene (St-Ip-Bd) tri-copolymer (Sn-SIBR) was prepared by anionic polymerization using self-made tin-containing organolithium (SnLi) as initiator, tetrahydrofuran (THF) as polar modifier, and cyclohexane as solvent. The microstructure and the glass-transition temperature (Tg) of tri-copolymers were characterized by 1H NMR and differential scanning calorimetry (DSC), respectively. The result shows that the non-1,4-structure content and the Tg of tri-copolymers increased with the increase of THF dosage and the initiator concentration or the decrease of polymerization temperature. We also obtained the relationships between the ln(T/Li)( THF/ SnLi, mole ratio) and the non-1,4-structure content, the non-1,4-structure content and the Tg of copolymers, respectively.

A novel Tin-functionalized integrated rubber of styrene-isoprene-butadiene tri-copolymer (SIBR) was prepared in the styrene (St)/isoprene (Ip) /butadiene (Bd) system with self-made tin-containing organolithium (simplified as SnLi) as initiator via living anionic polymerization. By means of several measures such as TEM, SEM and dynamic viscoelastometer, morphology, static mechanical properties, wear ability, dynamic heat build-up and dynamic viscoelasticity of Tin-functionalized SIBR (Sn-SIBR) were studied and compared with non-functionalized SIBR and NR/S-SBR (40/60) blend. The result shows that with improving antiskid properties and wear resistance, Sn-SIBR reduces the rolling resistance over 30%, which has excellent mechanic properties and dynamic properties. Sn-SIBR satisfies the overall property requirements of high-performance tire tread, and it is an ideal new style tread material for high-property environmental green tire.