A one-pot multicomponent reaction for synthesis of 1-amidoalkyl-2-naphthols catalyzed by PEG-based dicationic acidic ionic liquids under solvent-free conditions

Abstract  

A mild and efficient method was developed for preparation of amidoalkyl naphthols via one-pot three-component condensation of aldehydes with amides and 2-naphthol in the presence of polyethylene glycol (PEG)-based dicationic acidic ionic liquid as a powerful catalyst under solvent-free conditions. Excellent yields, short reaction time, simple work-up, and reusable catalyst are advantages of this procedure.     

Convenient,multicomponent, one-pot synthesis of highly substituted pyridines under solvent-free conditions

Highly substituted pyridine derivatives have been accessed through an efficient, one-pot, multicomponent reaction of aldehydes, malononitrile, and ammonium acetate in the presence of triethylamine as a catalyst under solvent-free conditions. This procedure affords the desired products in high purity and has advantages such as short reaction time, excellent yields, and simple workup procedure. This procedure affords the desired products in moderate to high yields and has such advantages as short reaction time and simple workup procedure.     

Zinc perchlorate catalyzed one-pot synthesis of 3,4-dihydropyrimidinones under solvent-free conditions

Abstract

In this paper, we report zinc perchlorate hexahydrate [Zn(ClO₄)₂?6H₂O] as a highly effective catalyst for the synthesis of 3,4-dihydropyrimidin-2(1H)-ones under solvent-free conditions. These improved reaction conditions allow the preparation of a wide variety of substituted dihydropyrimidinones in high yields and purity under mild reaction conditions. Compared with the classical Biginelli reaction, this method has the advantage of excellent yields and short reaction time in solvent-free conditions.     

无溶剂条件下碳基固体酸催化一锅法合成酰胺烷基萘酚(英文)

An efficient, environmentally friendly procedure for the synthesis of amidoalkyl naphthols through the one‐pot, three‐component reaction of β‐naphthol, aryl aldehydes, and acetamide in the presence of a carbon‐based solid acid under thermal solvent‐free conditions is described. The beneficial fea-tures of this new synthetic approach include short reaction time, high yields, clean reaction profiles, and a simple work‐up procedure. Furthermore, the catalyst can be readily recycled and reused four times without obvious significant loss of activity. The structure of the catalyst was confirmed by Fourier transform infrared spectroscopy, N2 adsorption/desorption analysis, and X‐ray diffraction.     

Meglumine sulfate catalyzed solvent-free one-pot synthesis of coumarins under microwave and thermal conditions

A convenient method has been developed for the Pechmann reaction of phenols and β-keto esters catalyzed by meglumine sulfate. Solvent-free conditions, inexpensive catalyst, short reaction times, high yield, and ease of purification of the products are the advantages of this protocol. This novel catalytic system is expected to contribute to the development of more benign Pechmann condensation reactions of phenols with β-keto esters.     

Solvent-free, one-pot synthesis of amidoalkyl naphthols by a copper p-toluenesulfonate catalyzed multicomponent reaction

Abstract  

An efficient synthesis of amidoalkyl naphthols using copper p-toluenesulfonate (CPTS) as catalyst for the three-component condensation reaction of 2-naphthol, aldehydes, and amides under thermal, solvent-free conditions is described. This new approach has advantages such as short reaction time, high yield, simple work-up, and reusable catalyst.     

Indium triflate catalyzed one-pot multicomponent synthesis of spiro-hexahydropyrimidines explained by multiple covalent bond formation

A mild, efficient, and expeditious method has been developed for the synthesis of spiro-hexahydropyrimidine derivatives via a three-component, one-pot cyclocondensation reaction of aromatic amines, formaldehyde, and cyclic ketones in 4-6 h using In(OTf)₃ as Lewis acid catalyst for the first time. The reaction involving creation of six new covalent bonds was efficiently promoted by 10 mol % In(OTf)₃ and the catalyst could be recovered easily after the reaction and reused without any loss of its catalytic activity. The advantageous features of this methodology are high atom-economy, operational simplicity, shorter reaction time, and easy handling.     

Green one-pot multicomponent synthesis of pyrrolidinones using planetary ball milling process under solvent-free conditions

This paper presents a novel and efficient protocol for the synthesis of pyrrolidinones using catalytic loading of 1,1'-butylenebis(3-sulfo-3H-imidazol-1-ium) hydrogen sulfate as a recyclable Brönsted acid ionic liquid through ball milling process at room temperature under solvent-free conditions. The developed method provides good to excellent yields of various pyrrolidinones in environmentally friendly conditions. Furthermore, this efficient protocol displays a combination of the synthetic advantage of one-pot multicomponent reaction with ecological benefits and convenience of a mechanochemical procedure.     

A straightforward one-pot multicomponent synthesis of polysubstituted pyrroles

Polysubstituted pyrroles were efficiently synthesized in moderate yields by a one-pot multicomponent reaction starting from primary amines, ethyl glyoxalate and 2-bromoacetophenones in the presence of pyridine in refluxing acetonitrile. This methodology was utilized to synthesize a highly substituted benz[g]indole.     

(Bromodimethyl)sulfonium bromide catalyzed efficient multicomponent one-pot synthesis of homoallylic amines

Three-component reactions of aldehydes, amines and allyltributylstannane in the presence of a catalytic amount of (bromodimethyl)sulfonium bromide have been accomplished in short reaction times to afford the corresponding homoallylic amines in excellent yields.     

A one-pot, microwave-influenced synthesis of diverse small molecules by multicomponent reaction cascades

Small molecule diversity can be achieved in a single synthetic operation from bifunctional substrates in the absence of additives and under the influence of microwaves with complete control of pathway selectivity. The preliminary Ugi four-component coupling products give rise to three structurally distinct scaffolds that are dependent on solvent effects and sterics. 2,5-Diketopiperazines (Type A), 2-azaspiro[4.5]deca-6,9-diene-3,8-diones (Type B), and thiophene-derived Diels-Alder tricyclic lactams (Type C) predominate in this reaction cascade.     

Study on catalytic synthesis of 1,3-benzodioxoles by HY zeolite

The acetalization and ketalization of various aldehydes and ketones with catechol by using HY zeolite as catalyst were studied. Effect of the reaction time, mole ratio of reactants, and amount of catalyst on the yield of benzodioxoles were investigated. Results show that HY is an efficient catalyst for the acetalization and ketalization with high conversion and selectivity in mild conditions. The best reaction conditions: molar ratio of catechol to aldehydes or ketones is 1:1.4, catalyst amount is 3.5 g/l mol catechol, reaction time is 5 h. Under these conditions, the conversion and selectivity were over 50% and 97%, respectively. Translated from Huaxue Tongbao 2006, 69(6) (in Chinese)     

PPA-SiO_2 catalyzed efficient synthesis of polyhydroquinoline derivatives through Hantzsch multicomponent condensation under solvent-free conditions

Silica gel-supported polyphosphoric acid（PPA-SiO₂） was found to be an efficient catalyst for the one-pot four-component Hantzsch condensation reaction of aryl aldehydes,dimedone,ethyl acetoacetate and ammonium acetate to afford the corresponding polyhydroquinoline derivatives in high yields.The main advantages of the present approach are short reaction times,clean reaction profiles,simple experimental and workup procedures.     

Ionic liquid/potassium hydroxide catalyzed solvent-free, one-pot synthesis of diarylglycolic acids from aromatic aldehydes under microwave

Ionic liquid in conjugation with KOH brings about an efficient, one-pot, green synthesis of α,α-diarylglycolic acids in reasonably high yields from aromatic aldehydes under solvent-free condition using conventional heating as well as microwave irradiation.     

Triton-B catalyzed,efficient one-pot synthesis of dithiocarbazates

A quick and efficient, one-pot synthesis of dithiocarbazates was accomplished in high yields by the reaction of various primary, secondary, and tert. alkyl halides with a variety of substituted hydrazines using the benzyl-trimethylammonium hydroxide (Triton-B)/CS₂ system. The reaction conditions are mild with simpler work-up procedures than the reported methods. Correspondence: Devdutt Chaturvedi, Medicinal and Process Chemistry Division, Central Drug Research Institute, Lucknow-226001, U.P., India.     

Triton-B catalyzed, efficient one-pot synthesis of carbazates

A quick and efficient, one-pot synthesis of carbazates was accomplished in high yields by the reaction of various primary, secondary, and tertiary alkyl halides with a variety of substituted hydrazines using the benzyltrimethylammonium hydroxide (Triton-B)/CO₂ system. The reaction conditions are mild with simpler work-up procedures than the reported methods. Correspondence: Devdutt Chaturvedi, Bio-Organic Chemistry Division, Indian Institute of Integrative Medicine, Canal Road, Jammu-Tawi 18000, J&K, India.     

Triton-B catalyzed, efficient one-pot synthesis of dithiocarbazates

A quick and efficient, one-pot synthesis of dithiocarbazates was accomplished in high yields by the reaction of various primary, secondary, and tert. alkyl halides with a variety of substituted hydrazines using the benzyl-trimethylammonium hydroxide (Triton-B)/CS₂ system. The reaction conditions are mild with simpler work-up procedures than the reported methods.