A microwave-assisted highly stereoselective one-pot Wittig reaction undersolvent-free conditions

Abstract

We report a novel microwave-assisted two-step, one-pot protocol for the synthesis of olefins (alkenes) via Wittig reaction. The reaction was carried out under solvent-free conditions using basic alumina both as a heterogeneous catalyst and a solid support. Varieties of aromatic aldehydes were converted into their corresponding olefins within 30-50 min with good to excellent yields. An excellent predominance of E -isomers over Z -isomers (up to 100% E-selectivity) for all the olefin products was observed. This showed the attractive stereocontrol of our reported protocol. In addition, owing to the solid-state nature of the reactions, our procedure prevented the need for tedious aqueous extraction at the end of the reaction, thereby adding another aspect to the greenness of the reaction.

Esterification of oleic acid to biodiesel using biowaste‐based solid acid catalyst under microwave irradiation

“…The NMR spectra of the produced biodiesel were recorded using deuterated chloroform (CDCl 3 ) as an internal reference on an AVANCE III 400 Ascend Bruker (300 MHz), Magnet: 8.96 T (superconducting) spectrometer. The percentage yield of the synthesized biodiesel was calculated using the Equation () 24 . On the other hand, the percentage conversion of oleic acid from the 1 H NMR data was calculated by using Knothe and Kenar Equation () 25 …”

“…The percentage yield of the synthesized biodiesel was calculated using the Equation ( 2). 24 On the other hand, the percentage conversion of oleic acid from the 1 H NMR data was calculated by using Knothe and Kenar Equation (3). 25…”