An Efficient and Novel Method for the Synthesis of β-Aroylpropionic Acids Under Solvent-Free Conditions

Abstract

A simple and rapid reaction of succinic anhydride with aromatic hydrocarbons is described. The reaction is conducted under Friedel–Crafts conditions in the absence of solvent at room temperature using aluminium chloride as catalyst.     

ZrOCl2·8H2O: An Efficient Catalyst for One-Pot Synthesis of α-Amino Phosphonates Under Solvent-Free Conditions

A highly efficient protocol has been developed for the three-component reaction of an amine, an aldehyde, and diethyl phopshite catalyzed by ZrOCl₂·8H₂O, an environmentally friendly catalyst, at ambient temperature. The catalyst exhibited remarkable activity and tolerated a wide variety of functional groups, providing the desired amino phosphonates in excellent yields under solvent-free conditions. Alternatively, the reaction rate can be significantly enhanced by carrying out the reaction in a monomode microwave reactor as a promoter.     

Iodine-catalyzed Efficient Synthesis of β-Keto Esters from Aldehydes and Ethyl Diazoacetate Under Solvent-free Conditions

An efficient procedure for the synthesis of β-keto esters from the reaction of aldehydes and ethyl diazoa-cetate catalyzed by iodine at room temperature under solvent-free conditions has been described. The catalytic procedure has the advantages of easily available catalyst,mild reaction conditions,high yields,and easy work-up.     

Reaction of α-Pinene and β-Pinene with Diethyl Hydrogen Phosphite Under Free Radical Conditions

We have found that α-pinene and β-pinene react with diethyl hydrogen phosphite (DEHP) and di-tert-butyl peroxide (TOOT) to form both mono- and diphosphonates. When the reaction was catalyzed by TOOT at 140-150[ddot]C, the major products were diphosphonates. Under comparatively mild initiation by benzoyl. peroxide at 80[ddot]C monophosphonate adducts were the major products.     

Stereoselective Synthesis of β-Amino Ketones: A Three-Component Mannich-Type Reaction of Aromatic Aldehydes,Anilines, and Cyclohexanone Using Amberlyst-15

A three-component Mannich-type reaction of aromatic aldehydes, anilines, and cyclohexanone in the presence of Amberlyst-15 affords the corresponding β-amino ketones in good yields at room temperature. The conversion is highly diastereoselective, favoring the formation of anti-isomers.     

Efficient Synthesis of β-Hydroxy Sulfides and β-Hydroxy Sulfoxides Catalyzed by Cu/MgO Under Solvent-Free Conditions

Regio-, stereo-, and chemoselective ring opening of epoxides with thiols using Cu/MgO as a heterogeneous catalyst has efficiently been carried out to produce the corresponding β-hydroxy sulfides in excellent yields at room temperature under solvent-free conditions. The treatment of the epoxides with thiols and 50% aqueous H₂O₂ in the presence of the same catalyst at room temperature affords the β-hydroxy sulfoxides in excellent yields.     

A Convenient Synthesis of Esters of β-Phenylglutamic Acid Under Aqueous Conditions

Abstract

Several esters of β-phenylglutamic acid (3, 4) are prepared by Michael reaction of glycine ester Schiff bases 1 and 2 under aqueous conditions.     

An Efficient One-pot Synthesis of β-Amino/β-Acetamido Carbonyl Compounds via ZrCl4-catalyzed Mannich-type Reaction

Zirconium(IV) chloride catalyzed efficient one-pot synthesis of β-amino/β-acetamido carbonyl compounds at room temperature is described. In the presence of ZrCl4, the three-component Mannich-type reaction via a variety of in situ generated aldimines, with various ketones, aromatic aldehydes and aromatic amines in ethanol, led to the formation of β-amino carbonyl compounds and the four-component Mannich-type reaction of aromatic aldehydes with various ketones, acetonitrile and acetyl chloride resulted in the corresponding β-acetamido carbonyl compounds in high to excellent yields. This methodology has also been applied towards the synthesis of dimeric β-amino/β-acetamido carbonyl compounds.     

Three-Component Reaction of Triphenylphosphine,Acetylenic Esters,and Arylsulfonyl Hydrazides or Aryl Hydrazines: An Efficient One-Pot Synthesis of Stable β-Nitrogen-Substituted Phosphorus Ylides

The three-component reaction between dialkyl acetylenedicarboxylates and triphenylphosphine in the presence of arylsulfonyl hydrazides or aryl hydrazines produces highly functionalized, salt-free phosphorus ylides in excellent yields.     

Sodium Dihydrogen Phosphate as an Efficient Catalyst for One-Pot,Three-Component Synthesis of α-Aminophosphonates Under Solvent-Free Conditions at Room Temperature

A simple, efficient, and general method has been developed for the one-pot, three-component synthesis of α-aminophosphonates from a condensation reaction of trimethyl phosphite, aldehydes, and amines in the presence of sodium dihydrogen phosphate under solvent-free conditions. Thus, α-aminophosphonates were synthesized relatively quickly in good yields at room temperature.     

Brønsted Acidic Ionic Liquid as an Efficient and Reusable Catalyst for One-Pot,Three-Component Synthesis of Pyrimidinone Derivatives via Biginelli-Type Reaction Under Solvent-Free Conditions

A mild and efficient method has been developed for the preparation of pyrimidinone derivatives from the reaction of aromatic aldehydes with cyclopentanone and urea or thiourea in the presence of N-(4-sulfonic acid) butyl triethyl ammonium hydrogen sulfate ([TEBSA][HSO₄]) as the Brønsted acidic ionic liquid and effective catalyst under thermal and solvent-free conditions. Good yields, short reaction times, straightforward workup, reusability of the catalyst, and green conditions are the most obvious advantages of this procedure.

Mg(ClO4)2, an Efficient Catalyst for Synthesis of β-Amino Alcohols by Ring Opening of Epoxides with Amines under Solvent-Free Conditions

Abstract

Commercially available magnesium perchlorate is reported as an extremely efficient catalyst for the ring-opening reaction of epoxide with various primary and secondary amines, especially diphenyl amine, under solvent-free conditions at room temperature.     

OH−/Silica-Mediated One-Pot Synthesis of Dithiocarbamates Under Solvent-Free Conditions

Abstract

An efficient, versatile, and environmentally benign method for the synthesis of dithiocarbamates under solvent-free conditions is reported. The Michael addition of electron-deficient alkenes with alkyl or aryl amines and CS₂ in the presence of OH^?/silica in a one-pot three-component reaction protocol gave the corresponding dithiocarbamates in good to excellent yields. This method is suitable for a wide range of amines and a variety of Michael acceptors in solvent-free conditions. The results of the present work show the desired products in excellent yields.     

Facile Sol-Gel Synthesis of Co3O4 Nanoparticles — An Efficient and Recyclable Catalyst for the Synthesis of 1,2-Disubstituted Benzimidazoles Under Solvent-Free Conditions

Russian Journal of Organic Chemistry - High-surface-area Co3O4 nanoparticles have been prepared as a potential heterogeneous catalyst by the sol-gel method using starch as an inexpensive and a...     

Simple Synthesis of Stable Phosphorus Ylides Derived from Imidazolidine-2-Thione. Efficient One-Pot Synthesis of α-Amino Esters with β-Phosphorus Substituents

Crystalline phosphorus ylides are obtained in nearly quantitative yields from the addition reaction between triphenylphosphine, dialkyl acetylenedicarboxylates, and imidazolidine-2-thione. A dynamic NMR effect is observed in the ¹ H NMR spectrum of the stabilized ylide obtained from dimethyl acetylenedicarboxylate (Δ G ^≠ = 66.6 kJmol^?1 ) and is attributed to restricted rotation around the carbon–carbon partial double bond resulting from the conjugation of the ylide moiety with the adjacent carbonyl group.     

Synthesis and Reaction of 4-Methyl-3,4-epithiotetrahydropyran with α-Amino Acids

4-Methyl-3,4-epithiotetrahydropyran was synthesized by the recyclization of 4-methyl-3,4-epoxytetrahydropyran by the action of thiourea. The product reacts with -amino acids in an alkaline medium with regioselective opening of the thiirane ring at the least substituted carbon atom.     

Ammonium Chloride–Catalyzed One-Pot Synthesis of 4(3H)-Quinazolinones Under Solvent-Free Conditions

Ammonium chloride, which is a very inexpensive and readily available reagent, can efficiently catalyze three-component, one-pot condensation reactions of 2-amino-benzoic acid esters, ortho esters, and aromatic amines to afford the corresponding 4(3H)-quinazolinones in good to excellent yields under solvent-free conditions.