Dicyclohexylcarbodiimide and catalytic dimethylaminopyridine were successfully used in the coupling of carboxylic acids with oxazolidinones and thiazolidinethiones. The acylated products were obtained in good yields.

No abstract

This study describes the preparation of blends between an amorphous polymer (PVC) and a crystalline polymer (PEO), with a third polymeric part that presents electronic conduction capacity (PEDOT-PSS). Binary (PEO/PVC, PEO/PEDOT-PSS, PVC/PEDOT-PSS) and ternary (PVC/PEO/PEDOT-PSS) blends were prepared by changing the concentrations of the constituents and were analyzed by electronic conductivity, Raman spatial resolution, infrared spectroscopies, and thermogravimetric analysis. The Raman and FTIR analyses showed the incorporation of PEDOT-PSS within the blends. The higher conductivity presented by the ternary blend was 8.6 ϫ 10 Ϫ6 Scm Ϫ1 , composed of 24% of PVC, 16% of PEO, and 60% of PEDOT-PSS. For binary blends the conductivity was proportional to the PEDOT-PSS content. The thermal stability could be observed through the TG curves of the blends that presented an increase of 19 K in the weight loss temperature at the 10% level when compared to the pure components.

No abstract

Niobium chloride promoted the nucleophilic addition of allyltrimethylsilane, ethyl acetoacetate, indole and the silyl enol ether derived from acetone to cyclic N-acyliminium ions. The products were obtained in good yields.