Zwitterionic Ring-Borylatedansa-Chromocene Complexes [J. Am. Chem. Soc.2002,124, 10996−10997].

y J . Am . Chem . Soc . 136 : 6453 − 6462

Cross-dehydrogenative coupling reactions between -ketoesters and electron-rich arenes, such as indoles, proceed with high regiochemical fidelity with a range of -ketoesters and indoles. The mechanism of the reaction between a prototypical ketoester, ethyl 2-oxocyclopentanonecarboxylate and N-methylindole, has been studied experimentally by monitoring the temporal course of the reaction by 1 ...

Am J

The repellency and insecticidal efficacy of Nopikex®, a soap formulation containing 20% diethyl toluamide and 0.5% permethrin, was evaluated against a laboratory colony of phlebotomine sand flies (Lutzomya longipalpis). The repellency of Nopikex soap was also compared with that of a placebo soap against another species (Lu. Youngi) in a forest near Tulua, Valle del Cauca, Colombia. In laborator...

Am J Clin Nutr

Zwitterionic bis(phenolate)amine lanthanide complexes for the ring-opening polymerisation of cyclic esters.

The reaction of Sm{N(SiMe3)2}3 with the bis(phenol)amines H2O2N(R) (H2O2N(R) = RCH2CH2N(2-HO-3,5-C6H2(t)Bu2)2; R = OMe, NMe2 or Me) gave exclusively zwitterions Sm(O2N(R))(HO2N(R)). For R = OMe or NMe2 these were efficient catalysts for the ring-opening polymerisation of epsilon-caprolactone and D,L-lactide with a tendency to form cyclic esters; in contrast, no polymerisation was observed for R...

Isoselective ring-opening polymerization of rac-lactide initiated by achiral heteroscorpionate zwitterionic zinc complexes.

A highly isotactic stereoblock PLA has been obtained using the achiral heteroscorpionate zwitterionic zinc complexes as catalysts, for the first time, via a chain-end control mechanism.