Polymers with a low molecular weight derived from soybean oil have been prepared in a supercritical carbon dioxide medium by cationic polymerization. Boron trifluoride diethyl etherate was used as an initiator. Influences of polymerization temperature, amount of initiator, and carbon dioxide pressure on the molecular weight were investigated. It is shown that the higher polymerization temperatu...

hexane was shaken with 2 ml. of boron trifluoride etherate, BF3 + (C2H6)20 (b.-p. 124-126°), at room temperature. The dark blue complex was decomposed by the addition of 100-200 ml. of 95% methanol, then transferred with water into hexane. The hypophase was discarded and the epiphase washed, dried, adsorbed on a suitable lime-celite column (2:1) and developed with hexane. The respective zones w...

Ring-opening polymerization of epoxidized soybean oil (ESO) catalyzed by boron trifluoride diethyl etherate (BF3 OEt2) in methylene chloride was conducted in an effort to develop useful biodegradable polymers. The resulting polymerized ESO (PESO) were characterized using infrared (IR) spectroscopy, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), H NMR, C NMR, solid st...

A series of artemisinin (1) derivatives containing bromo and heterocyclic or aromatic amine functions was prepared in the search for analogues with good water solubility and high antimalarial activity. Treatment of dihydroartemisinin (2a) with boron trifluoride etherate at room temperature gave the key intermediate, 9,10-dehydrodihydroartemisinin (3), which, on reaction with bromine, gave the d...

Selective deprotection of 4-(alkoxysilyl)benzaldehyde diethyl acetals 1a-1c in the two-solvent system of hydrochloric acid and chloroform gave 4-(alkoxysilyl)benzaldehydes 2a-2c in good yields. Under these conditions, undesired hydrolysis of the alkoxysilyl group was minimized. The reaction of benzaldehydes 2a and 2b with pyrrole in the presence of boron trifluoride diethyl etherate led to 5,10...