Organic Communications Articles

The stereoselective synthesis of the (C1-C24) fragment of Antanapeptin–A is described. The required stereochemistry of b -hydroxy- a -methyl acid unit was accomplished through Aldol reaction using Evans’ chiral auxiliary followed by the installation of terminal alkyne with Ohira–Bestmann reagent.

Three representative carbonyl compounds were efficiently hydrogenated in a glycerol-triac etin e or glycerol-tributyrin mixture. The addition of triacetin to glycerol favorably altered the polarity of the reaction mixture, thereby increasing the solubility of reactants and, in turn, reactant conversion rates. Maximum conversion was detected in an 80%-20% a glycerol-triacetin mixture ( 80 :2 0 ) in the presence of a Ru(p-cymene)Cl 2-dimer catalyst.

A simple and efficient method for synthesis of ester functionalized 2-pyridone derivatives (4a-m) via tri component reaction of primary amine, mono ester acetylene and diester acetylene using KF/alumina as catalyst under microwave irradiation is reported.

A three steps synthesis of non-symmetric 1,4-dialkoxybenzenes starting from 4-hydroxybenzaldehydes was described. At first step 4-alkoxyphneols were alkylated to give 4-alkoxybenzaldehydes. At the second step 4-alkoxybenzaldehydes were submitted to a Baeyer-Villiger oxidation with 30% H 2O 2 to afford 4-alkoxyphenols. At the last step 4-alkoxyphenols were secondly alkylated to give the title compounds.