Knoevenagel Condensations Catalyzed by New Oil Shale Recyclable Catalyst at Room Temperature and Assisted by Ultrasounds Irradiations

Abstract

Functionalized alkenes were successfully synthesized via a clean procedure in a short time by using a new recycled heterogeneous catalyst prepared from Moroccan oil shale, this catalyst is characterized by different technics such XRD, BET-BJH, MEB-EDS, and TGA, before it’s has been used in the Knoevenagel condensation between different aldehydes and active methylenes. The results showed that coupling the catalyst with ultrasound irradiations could improve the catalytic system in this transformation by achieving the products in a very short time, the results showed clearly that this catalyst could be considered as excellent recyclable support in Knoevenagel condensation.

Polyphosphazene‐Functionalized Microspheres as Efficient Catalysts for the Knoevenagel Reaction under Mild Conditions

“…[11] The natural oil shale catalyst also provides the influence of strong polarity on Knoevenagel condensation, and only 63 % and 33 % are reached in methanol and n-hexanol respectively. [36] Among the five solvents in this experiment, a nearly complete reaction is observed in ethanol, indicating that higher yield could be achieved in polar solvents. This behavior can be explained in terms of the reported effects of solvents on Knoevenagel condensation.…”

“…Toward the amine‐functionalized SiO 2 , only 40 % yield can be obtained in THF even at 50 °C [11] . The natural oil shale catalyst also provides the influence of strong polarity on Knoevenagel condensation, and only 63 % and 33 % are reached in methanol and n ‐hexanol respectively [36] …”

Mineral Oil Shale Part Based-Support as Heterogeneous Catalyst for Organophosphorus Synthesis Assisted by Ultrasounds

“…The raw matter comes from the Tarfaya region, Morocco, the catalyst has been prepared as described previously 37 . The structural and textural proprieties of the obtained catalyst have been studied using X-ray diffraction, FX, MEB-EDS and BET-BJH analysis.…”

“…In this paper, we present the use of this raw matter as heterogeneous catalyst. We present here a simple, rapid, environmentally friendly and high yielding protocol for the synthesis of α-hydroxyphosphonates in in dry media at room temperature or under ultrasonic irradiations (Scheme 1), this elaborated support has been used successfully in Knoevenagel reaction 37 .…”