Solvent‐Free Synthesis of Benzothiazolines in the Presence of Alumina

o‐Aminothiophenol reacted with ketones and β‐keto esters in the presence of alumina under mild and solvent‐free conditions to afford the corresponding benzothiazolines in high yields. Alumina can be reused for subsequent reactions without any loss of the activity.     

Regioselective Aromatic Electrophilic Bromination with Dioxane Dibromide Under Solvent‐Free Conditions

Highly regioselective ring bromination of aromatic compounds has been accomplished with high yields and good purity using dioxane dibromide (DD) under solvent‐free conditions. Notable features of this methodology include operational simplicity, rapid reactions, excellent control over the degree of bromination, and tolerance of various functional groups during the reaction.     

Lithium Perchlorate Mediated Three‐Component Preparation of α‐Aminonitriles Under Solvent‐Free Conditions

Abstract

A three‐component reaction between aliphatic or aromatic aldehyde, an amine and trimethylsilyl cyanide mediated by solid LiClO₄, gave amino nitriles in good to excellent yields. The reaction proceeded smoothly under solvent‐free conditions without any side products.     

Efficient and Environmentally Friendly Approach to the Synthesis of Ferrocenyl‐Substituted 1,5‐Diketone Compounds Under Solvent‐Free Conditions

Abstract

This article describes a fast, efficient, economical, and environmentally friendly method for the preparation of a series of ferrocenyl‐substituted 1,5‐diketone compounds via Michael addition of ferrocenyl‐substituted chalcones with deoxybenzoin or dibenzyl ketone under solvent‐free conditions, and affords the corresponding Michael adducts with excellent yields of 77–93%.     

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.     

One‐Pot Synthesis of Iminoimidazolines under Microwave Irradiation in Solvent‐Free Conditions

Substituted iminoimidazolines were synthesized from a one‐pot reaction of aromatic or hetero‐aromatic amines with imidazolidine‐2‐thione under solvent‐free conditions using microwave irradiation with good to excellent yields.     

Facile Synthesis of Pyrano[2,3‐c]pyrazol‐6‐one Derivatives Under Microwave Irradiation in Solvent‐Free Conditions

A series of substituted 1H,6H‐pyrano[2,3‐c]pyrazol‐6‐one derivatives were synthesized from one‐pot cyclocondensation of hydrazine derivatives or 1H‐pyrazol‐5‐one derivatives with various β‐keto esters under solvent‐free conditions using microwave irradiation in short time with good to excellent yields.     

An Efficient,Simple, and Eco‐Friendly Method for the Synthesis of Sydnone‐Containing Thiazoles Under Solvent‐Free Conditions

Abstract

Novel 4‐substituted‐3‐(3‐substituted sydnolydine‐4‐hydrazono)thiazoles 3a‐l have been synthesized under solvent free conditions by grinding the reactants in a mortar with a pestle.     

InCl3 as an Efficient Catalyst for Cyclotrimerization of Aldehydes: Synthesis of 1,3,5‐Trioxane Under Solvent‐Free Conditions

1,3,5‐Trioxanes derived from aldehydes were synthesized using indium trichloride as a catalyst. Cyclotrimerization of the aldehydes gave excellent yields under neat conditions within a short span of time.     

Synthesis of 2‐Substituted 4,5‐Diphenyloxazoles under Solvent‐Free Microwave Irradiation Conditions

A novel method for the direct conversion of deoxybenzoin into 2‐alkyl‐4,5‐diphenyloxazoles and 2‐aryl‐4,5‐diphenyloxazoles has been developed using treatment of HTIB and nitriles under solvent‐free microwave irradiation conditions.     

Efficient Green Procedure for the Knoevenagel Condensation under Solvent‐Free Conditions

Knoevenagel condensation of aromatic aldehydes with active methylene compounds under solvent‐free conditions to synthesize arylidene compounds by grinding in the presence of TEBA at room temperature has been described. This method is simple, efficient, and environmentally friendly.     

Reactions of Binor-S with α,ω-Diols and Organic Acids in the Presence of Inorganic Ionic Liquids

Russian Journal of Organic Chemistry - New methods have been developed for the synthesis of previously unknown ω-(hexacyclo[9.2.1.02,7.03,5.04,8.09,13]tetradecan-10-exo-yloxy)alkan-1-ols and...     

Microwave‐Induced Conversion of Acid Hydrazides to N,N′‐Diacylhydrazines in Solvent‐Free Conditions

A new and efficient method of converting acid hydrazides 1 to the corresponding N,N′‐diacylhydrazines 2 under microwave irradiation and in solvent‐free conditions has been described.     

Efficient DMF‐Catalyzed Coupling of Epoxides with CO2 under Solvent‐Free Conditions to Afford Cyclic Carbonates

To develop a simple, low‐molecule, and cost‐effective organocatalyst for the coupling of epoxides with CO₂, we have screened this coupling reaction in different organic solvents and found that DMF is an efficient organic catalyst for the coupling of epoxides with CO₂ to give cyclic carbonates in high yield. In some cases, the catalytic activity of DMF can be significantly increased by the addition of catalytic amount of H₂O.     

PEG‐SO3H as Catalyst for 3,4‐Dihydropyrimidones via Biginelli Reaction Under Microwave and Solvent‐Free Conditions

An efficient and environmentally friendly process for the synthesis of 3,4‐dihydropyrimidones via the Biginelli‐type condensation reaction using poly(ethylene glycol)‐bound sulfonic acid as catalyst irradiated by microwave has been developed. The functionalized poly(ethylene glycol) acted simultaneously as catalyst and as solvent in the condensation. The workup was easy, and the products were obtained in good to excellent yields and high purities.     

Reactions of Some Terpenoids with CH-Acids in the Presence of Cs-β Zeolite

Reactions of some ,-unsaturated ketones from terpenoid series with CH-acids in the presence of Cs- zeolite were studied under various conditions. The variation of reaction conditions (heating, ultrasonic irradiation) strongly affected the reaction products ratio, and the effect was singular in each case and gave different results.     

One‐Pot Preparation of Fluorinated α‐Aminoalkyl Phosphonates under Microwave Irradiation and Solvent‐Free Conditions

A facile one‐pot method has been developed for the synthesis of fluorine‐containing α‐amino phosphonates in good yields by a three‐component reaction of fluorinated aromatic aldehydes, anilines, and diethyl phosphate in the presence of a silica‐gel support under microwave irradiation within 10 min. All new compounds are fully characterized by spectral methods and elemental analysis.     

Facile One‐Step Conversion of Ketones into α‐Azidoketones using [Hydroxy(tosyloxy)iodo]benzene and Sodium Azide in the Presence of a Phase‐Transfer Catalyst under Solvent‐Free Conditions

We have described a one‐step, solvent‐free synthesis of α‐azidoketones from the corresponding ketones that requires relatively benign [hydroxy(tosyloxy) iodo]‐benzene reagent, sodium azide, and phase‐transfer catalyst at room temperature. Generality of the protocol has been demonstrated by synthesizing various α‐azidoketones high in yield and purity within a short time.     

Solvent‐Free,One‐Pot Synthesis of Pyrano[2,3‐c]pyrazole Derivatives in the Presence of KF·2H2O by Grinding

Abstract

A solvent‐free, one‐pot process for the preparation of 4H‐pyrans in the presence of KF?·?2H₂O by grinding was achieved. Its advantages are easy workup, mild reaction conditions, high yields, and environmental friendliness.     

Convergent One‐Pot Synthesis of 3‐Substituted Quinazolin‐4(3H)‐ones under Solvent‐Free Conditions

A convenient method for the synthesis of 3‐substituted quinazolin‐4(3H)‐ones using the convergent reactions of formic acid, a primary amine, and isatoic anhydride under solvent‐free conditions and with brief microwave irradiation is described.