Synthesis of N-Substituted Pyrroles Under Catalyst- and Solvent-Free Conditions

N-Substituted pyrroles were synthesized under neat conditions by the reaction of aromatic amines with 2, 5-dimethoxytetrahydrofuran in excellent yields.     

Synthesis of Thiocarbamates from Thiols and Isocyanates Under Catalyst- and Solvent-Free Conditions

Summary. A simple and efficient procedure was developed for the synthesis of S-alkyl (aryl) thiocarbamates under solvent-free conditions without the use of a catalyst. The significant features of this protocol are (a) operational simplicity, (b) mild reaction conditions, (c) short reaction times, (d) solvent-free conditions, and (e) high product yields.     

无溶剂研磨条件下四氢苯并吡喃衍生物的一锅法合成

四氢苯并吡喃衍生物在药物和农药研究中有着广泛的用途. 基于合成这类化合物的传统方法所用溶剂多为对环境不利的极性溶剂, 且合成需分步进行, 在提倡绿色化学和发展节约型经济的今天, 如何改良这类反应已成为一个热点. 本工作通过选择不同的碱尝试反应最佳条件, 发现用价廉易得的碳酸钾为碱, 对不同官能团取代的底物芳醛采用研磨的手段, 在无溶剂条件下, 一锅法可成功合成四氢苯并吡喃衍生物. 该法条件温和, 收率高, 易于操作, 对环境影响小.     

One-Pot Synthesis of 3,5-Disubstituted 1,2,4-Oxadiazoles Directly from Nitrile and Hydroxylamine Hydrochloride Under Solvent-Free Conditions Using Potassium Fluoride as Catalyst and Solid Support

A one-pot synthesis of 3,5-disubstituted 1,2,4-oxadiazoles with two identical substituents directly from the reaction of nitriles and hydroxylamine hydrochloride in the presence of potassium fluoride as catalyst and solid support under solvent-free condition is described. Moreover, the formation of products has been discussed, and a plausible mechanism has been presented. Simplicity of the process, workup in aqueous media, and excellent yields are some advantages of this method.     

Efficient and Facile Synthesis of 3-Amino-1-aryl-9H-fluorene-2,4-dicarbonitrile Under Solvent-Free Conditions

A versatile and efficient route to 3-amino-1-aryl-9H-fluorene-2,4-dicarbonitrile via multicomponent reactions of 1-indanone, aromatic aldehydes, and malononitrile under solvent-free conditions using NaOH as the catalyst is described. This method provides several advantages over alternative procedures such as mild, solvent-free conditions at ambient temperature and direct isolation of the products in good yields.     

Green One-Pot Synthesis of 2H-Pyrans Under Solvent-Free Conditions Catalyzed by Ethylenediammonium Diacetate

Ethylenediammonium diacetate readily catalyzes the Knoevenagel-type condensation between 1,3-dicarbonyl substrates and α,β-unsaturated aldehydes at room temperature under solvent-free conditions. This rapid, efficient, and convenient one-pot approach to the synthesis of 2H-pyrans stands as a significant advance over previously reported protocols. This environmentally friendly methodology has been successfully applied to the synthesis of biologically active natural products of interest zanthosimuline, N-methylflindersine, and ferprenin.

Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications ^® to view the free supplemental file.     

Efficient Synthesis of Urea Derivatives via a Sequential One-Pot Nucleophilic Addition/Ugi Five-Component Reaction Under Solvent-Free Conditions

Urea polyfunctional derivatives were successfully synthesized via a one-pot, five-component nucleophilic addition/Ugi reaction sequence. Simplicity, solvent-free conditions, and good yields of products are advantages of this method.     

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.     

无溶剂条件下"一锅法"催化合成胺基烷基萘酚衍生物

无溶剂条件下,邻甲基苯磺酸铜可有效催化2-萘酚、醛和胺三组分"一锅法"合成胺基烷基萘酚衍生物.考察了溶剂条件及催化剂用量对产率的影响.经催化剂循环研究,该催化剂重复使用4次仍保持较高活性.产物的结构通过熔点,IR,1HNMR,13CNMR,质谱和元素分析进行测定和结构表征.同时给出了该反应可能的反应机理.     

Atom-Efficient,Solvent-Free,Green Synthesis of Chalcones by Grinding

An improved Claisen–Schmidt condensation reaction of methyl ketones and aromatic aldehydes can be achieved by grinding at room temperature in the absence of solvents. This process is simple, efficient, economical, and environmentally benign compared to classical reactions.     

Efficient Synthesis of Ferrocenylcyclohexenone Under Solvent-Free Conditions

An efficient method for the synthesis of a series of ferrocenylcyclohexenones via tandem Michael–aldol reaction of ferrocenyl-substituted chalcones with dibenzyl ketone under solvent-free conditions is described. It was found that the factors including the electronic nature of chalcone, basicity of the base, reaction time, and temperature have effects on the formation of the ferrocenylcyclohexenones.     

无溶剂无催化剂条件下二硫代氨基甲酸酯衍生物的合成研究

主要研究了二硫代氨基甲酸酯衍生物的合成,将脂肪胺、CS2与α,β-不饱和羰基化合物或卤代烃在无溶剂无催化剂室温条件下,"一锅法"进行了Michael-type的加成反应,合成了二硫代氨基甲酸酯衍生物.该方法产率高,操作简单,是一种原子经济的合成方法,并可大规模地用于制药及农药方面.     

One-Pot Synthesis of Mannich Bases Under Solvent-Free Conditions

A mild and practically convenient one-pot procedure for the Mannich reaction via condensation of amines, aldehydes and malonates, β-ketoesters, or β-dicarbonyl compounds has been carried out without using any organic solvent, metallic catalyst, or Lewis acids or bases at room temperature. The present protocol offers several advantages, such as goods yields, simple procedure with easy workup, and the absence of any volatile, hazardous organic solvents and metallic catalyst.     

Efficient and Facile Synthesis of 2,4-Diamino-6-arylpyrimidine-5-carbonitrile Under Solvent-Free Conditions

An efficient and convenient method for the preparation of 2,4-diamino-6-arylpyrimidine-5-carbonitrile derivatives by the one-pot reaction of aromatic aldehydes, malononitrile, and guanidine carbonate, in the presence of sodium hydroxide under solvent-free conditions, was reported. This method has the advantages of excellent yields, mild reaction conditions, easy work up, and environmental friendliness over the existing procedures.     

Efficient One-Pot Synthesis of Benzimidazoles Under Solvent-Free Conditions

A green, efficient method for the synthesis of various 2-aryl-benzimidazoles in the presence of hypervalent iodine as the oxidant at room temperature under solvent-free conditions is reported. The salient features of this method include mild conditions, short reaction times (3–5 min), excellent yields, and simple procedure.     

Simple Synthesis of Pyrroles Under Solvent-Free Conditions

Paal–Knorr condensation of 2,5-hexadione with primary amines in the presence of a catalytic amount of praseodymium(III) trifluoromethanesulfonate under solvent-free conditions has been accomplished with an excellent yield. This method is a very easy, rapid, and high-yielding reaction for the synthesis of N-substituted pyrrole derivatives.     

Highly Efficient Synthesis of Trioxopyrimidine-Based Chalconoids Under Solvent-Free Conditions

Straightforward procedures for the fast and efficient synthesis of differently substituted barbituric acid–based chalconoids under solvent-free conditions were developed.     

A Rapid and Efficient Multicomponent Synthesis of Bi-Quinolines Under Solvent-Free Conditions

An efficient synthesis of substituted condensed quinolino-quinolines has been achieved in a one-pot reaction from 2-hydroxy/mercapto/seleno-4-methylquinoline and 2-mercapto/seleno-3-formyl quinolines using anhydrous ammonium hydroxide as the reductant by microwave irradiation under solvent-free conditions.     

无溶剂条件下芳香醛与氯代苯乙酮的Darzens 缩合反应

在无溶剂、氢氧化钠的作用下, 用研磨的方法、通过Darzens缩合反应制备环氧化合物. 它的优点是操作简单、反应条件温和、产率高和环境污染小.