α-AMIDOALKYLATION VIA SULFONES:TOWARDS THE SYNTHESIS OF ANT VENOM ALKALOIDS

Abstract: We described the synthesis of two 5-substituted γ-lactams Ⅰand Ⅱ by sulfone-baaed α-amidoalkylation method. This constitiutes the formal synthesis of ant venom alkaloids 2 and 3 in racemic form. The key intermediate 18 for the chiral synthesis of 2 and 3 was prepared from new chiral sulfone 7 by the same method.

Silica supported perchloric acid(HClO_4-SiO_2):A mild,reusable and highly efficient heterogeneous catalyst for the synthesis of amidoalkyl naphthols

An efficient and direct procedure has been developed for the preparation of amidoalkyl naphthols by a one-pot condensation of aryl aldehydes, 2-naphthol and urea or amides, in the presence of HClO4-SiO2 as a heterogeneous catalyst. The reactions were carried out under reflux and solvent-free conditions. The present methodology offers several advantages such as excellent yields, simple procedure, easy work-up and ecofriendly reaction condition. The catalyst is easily prepared, stable, reusable and efficient under the reaction conditions.

Wet cyanuric chloride promoted efficient synthesis of amidoalkyl naphthols under solvent-free conditions

An efficient and direct procedure has been developed for the preparation of amidoalkyl naphthols by a one-pot condensation of aryl aldehydes, 2-naphthol and urea or amides, in the presence of wet-cyanuric chloride （wet-TCT） as a catalyst. The reactions were carried out under solvent-free media. The present methodology offers several advantages such as excellent yields, simple procedure and eco-friendly reaction condition.

Nano-sulfated zirconia as an efficient,recyclable and environmentally benign catalyst for one-pot three component synthesis of amidoalkyl naphthols

One pot synthesis of amidoalkyl naphthols by reaction of aromatic aldehydes,2-naphthol and amide/urea using nano-sulfated zirconia as a catalyst is reported.The reaction was carried out under solvent-free conditions.The method gave good yields of amidoalkyl naphthols in short reaction time.The catalyst is recycled for five consecutive times without loss of activity.

Three-component synthesis of amidoalkyl naphthols catalyzed by bismuth(Ⅲ) nitrate pentahydrate

Bismuth（Ⅲ） nitrate pentahydrate catalyzed the three-component condensation ofβ-naphthol,aldehydes and amines/urea under solvent-free conditions to afford the corresponding amidoalkyl naphthols in excellent yields.

l-Hexanesulphonic acid sodium salt promoted the one-pot synthesis of amidoalkyl naphthols under microwave-irradiation

Amidoalkyl naphthols have been synthesized in high yields in the presence of 1-hexanesulphonic acid sodium salt as an inexpensive solid catalyst under solvent-free conditions and microwave-irradiation.This catalyst provides clean conversion;greater selectivity and easy workup make this protocol practical and economically attractive.

Silica Supported Methanesulfonic Acid as an Efficient and Reusable Heterogeneous Catalyst for the Synthesis of Amidoalkyl Naphthols

A green protocol for the preparation of amidoalkyl naphthols from three-component one-pot condensation of 2-naphthol, aldehydes, amides or urea in the presence of silica supported methanesulfonic acid under thermal sol- vent-free conditions has been described. The catalyst is stable, efficient, easily prepared, and reusable. The remarkable features of this methodology are short reaction time, excellent yields, simple experimental and work-up procedures.