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Oxygen ligation is envisioned to provide a stable and distinctive coordination environment to the strongly oxophilic rare-earth metals. However, the well-defined dialkyl complexes bearing oxyanion ancillary ligand had been rarely addressed for the instability of the complexes and the shortage of easily available ligands. Herein, we report the synthesis of phosphate ligated dialkyl yttrium complexes (PYR2) featuring a high stability and a tunable ligand. Treated with the borate reagent, the phosphate yttrium complex displays high activity and selectivity in the catalytic cis-1,4-polymerization of isoprene (up to 96.5%). Furthermore, using AlMe3 as an additive, the stereoselectivity switches to trans-1,4-polymerization (up to 92.0%).

N-Alkylated benzimidazole derivatives have been synthesized via the aza-Michael addition reactions of 1H-benzimidazoles to α,β-unsaturated compounds in water and palladium acetate obviously promoted these transformations. The reported method, overcoming the inactivation of palladium under the equivalent nitrogenous conditions, has the advantages of convenient manipulation, atom-economy, as well as environmental friendliness. The bioactive results showed that butyl 3-(5,6-dimethyl-1H-benzo[d]imidazol-1-yl)propanoate (3c) exhibited excellent inhibitory activity against Bacillus subtilis (MIC = 16 μg/mL) and Bacillus proteus (MIC = 8 μg/mL). Therefore, this process would facilitate the construction of various potential bioactive compounds based on the benzimidazole scaffold under mild conditions.

Lewis acidic ionic liquids were used to catalyze the reaction of epoxypropane with POCl 3 . Considering the lower cost and catalytic activities, we concluded that [Et 3 NH]Cl/AlCl 3 was the most attractive ionic liquid from an economical point of view. But it would be easily inactivated because of sensitive to water and air. Moreover, it could not be reused easily because of difficulty recovery in the reaction. However, supporting [Et 3 NH]Cl/AlCl 3 catalyst could resolve above problems. Supporting [Et 3 NH]Cl/AlCl 3 catalyst could be separated by filter easily and reused 5 times in 98% yield. Furthermore, the catalyst was applicable to other epoxy ether cleaving reactions.

Poly(d,l-lactide-co-p-dioxanone) (P(LA-co-PDO)) copolymers with different chain microstructures were synthesized by one-step or two-step bulk ring-opening polymerizations of d,l-lactide (LA) and p-dioxanone (PDO) monomers using stannous octoate [Sn(Oct)2]/n-dodecanol as the initiating system. The average sequence lengths of the lactidyl (LLA) and dioxanyl (LPDO) units were calculated from the 1H NMR spectra. It was found that both LLA and LPDO values from the two-step syntheses were significantly longer than those from the corresponding one-step syntheses, indicating more blocky structure achieved for the two-step copolymers. Corresponding to this difference in microstructure, the two-step copolymers were semi-crystalline, while the one-step copolymers were completely amorphous. In conclusion, the crystallinity of P(LA-co-PDO) copolymers could be adjusted conveniently to meet specific applications by changing the microstructure of the copolymers via different polymerization routes.

A novel polyethylene glycol (PEG)-200-based dicationic acidic ionic liquid (PEG200-DAIL) was used to synthesize HMX from DPT by nitrolysis with N2O5. It was found that either N2O5 or PEG200-DAIL could improve the yield. Furthermore, the combined use of PEG200-DAIL and N2O5 could increase the yield of HMX to 64% with the used quantity of HNO3 decreased dramatically.