Saïd Sebti

Modified natural phosphates: easily accessible basic catalysts for the epoxidation of electron-deficient alkenes

Natural phosphate is basic enough to promote the epoxidation of electron-deficient alkenes with dilute aqueous hydrogen peroxide. A simple modification with sodium nitrate leads to the probably most active, water compatible and recyclable basic catalyst described for this reaction. It promotes the epoxidation of a large variety of alkenes.

ZINC CHLORIDE DOPED NATURAL PHOSPHATE AS 1,3-DIPOLAR CYCLOADDITION CATALYST

Abstract Catalytic behaviour has been observed for zinc chloride doped natural phosphate for the 1,3-dipolar cycloaddition reactions. It provides an easy route for the preparation of new nucleosides and acyclonucleosides containing a 1,2,3-triazolering.

Transesterifications catalysed by solid, reusable apatite–zinc chloride catalysts

We report for the first time the use of low cost and safe to handle fluoroapatite and hydroxyapatite supported zinc chloride reagents as solid and reusable catalysts for a wide range of transesterification reactions

FLUORAPATITE/SODIUM NITRATE AS A SOLID SUPPORT FOR THE KNOEVENAGEL REACTION

The Knoevenagel reaction is assisted by sodium nitrate/fluorapatite in heterogeneous media. The reaction is carried out between an activated methylene and an aldehyde at room temperature without a solvent. The yields obtained are very high.

Lewis Acid–Doped Natural Phosphate: New Catalysts for the One‐Pot Synthesis of 3,4‐Dihydropyrimdin‐2(1H)‐one

Abstract Inexpensive and readily available natural phosphate doped with metal halides is used to efficiently catalyze the three‐component condensation reaction of an aldehyde, a beta‐keto ester, and urea to afford the corresponding dihydropyrimidin‐2(1H)‐ones in high yields.

Uncatalysed preparation of α-amino phosphonates under solvent free conditions

A simple, efficient and environmentally friendly procedure has been developed for the three component coupling of carbonyl compounds, aromatic and aliphatic amines and dialkyl phosphites to produce α-amino phosphonates. The α-amino phosphonates are synthesised in high yields (74–97%) in a few minutes (1–3 min) by microwave irradiation under solvent-free conditions, avoiding the use of any catalyst.

Transesterification of Methylbenzoate with Alcohols Catalyzed by Natural Phosphate

Abstract Transesterification of methylbenzoate with various alcohols was catalyzed by natural phosphate with or without solvent in heterogeneous media. The molar ratio of alcohol/ester, solvent effect, and weight of catalyst effect have been studied. We have found that the nature of alcohol and the reaction temperature play an important role in the transesterification process. The catalyst can be regenerated and reused without lost of activity.

Natural microphosphate as a catalyst for Knoevenagel condensation: specific surface effect

The effect of specific surface of natural phosphate on Knoevenagel condensations involving aldehydes and activated methylene is studied. The best catalytic activities were observed with catalyst micronised (NPm).

Doped Natural Phosphate: A New and Environmentally Friendly Catalyst in Nucleoside Synthesis

Abstract Doped natural phosphate is used as acidic or basic catalyst in nucleoside and acyclonucleoside synthesis. Some examples are given.

One-Pot Synthesis of Antiviral Acyclovir and Other Nucleosides Derivatives Using Doped Natural Phosphate as Lewis Acid Catalyst

Natural phosphate doped with iodine or potassium iodide is an active catalyst for the one-pot synthesis of acyclonucleosides. To demonstrate the utility of the new catalyst system, the highly important antiviral drug acyclovir was directly and regioselectively obtained from NAcG with no byproducts.