Esters of 4-formylpyrazol-3-carboxylic acids

Microbial transformation of esters of chlorinated carboxylic acids.

Two groups of compounds were selected for microbial transformation studies. In the first group were carboxylic acid esters having a fixed aromatic moiety and an increasing length of the alkyl component. Ethyl esters of chlorine-substituted carboxylic acids were in the second group. Microorganisms from environmental waters and a pure culture of Pseudomonas putida U were used. The bacterial popul...

Conversion of 4-oxoproline esters to 4-substituted pyrrole-2-carboxylic acid esters.

The Grignard, Wittig, Tebbe, Horner-Emmons, and Reformatsky reactions of the 4-oxoproline esters gave the corresponding 4-alylated or 4-alkylidenated products, respectively. The products were properly treated with bases to cause aromatization, giving 4-substituted pyrrole-2-carboxylic acid esters such as methyl 4-methylpyrrole-2-carboxylate, which is a trail pheromone of Atta texana.

Iron-catalysed green synthesis of carboxylic esters by the intermolecular addition of carboxylic acids to alkenes.

Iron triflate, in situ-formed from FeCl3 and triflic acid, or FeCl3 and silver triflate efficiently catalyse the intermolecular addition of carboxylic acids to various alkenes to yield carboxylic esters; the reaction is applicable to the synthesis of unstable esters, such as acrylates.

Esters of Omega-3 Fatty Acids

PolyVinylPolyPyrrolidone-Supported Boron Trifluoride (PVPP-BF3); Highly Efficient Catalyst for Oxidation of Aldehydes to Carboxylic Acids and Esters by H2O2

A highly efficient method for the oxidation of aldehydes to carboxylic acids using PolyVinylPolyPyrrolidone supported - Boron Trifluoride (PVPP-BF3) in the presence of 35% hydrogen peroxide has been developed in acetonitrile at 60 °C. This procedure cleanly oxidizes variety of aldehydes to the corresponding carboxylic acids. Oxidative esterification of benzaldeh...