Silica supported sodium hydrogen sulfate （NaHSO4/SiO2）： A mild and efficient reusable catalyst for the synthesis of aryl-14-H-dibenzo [aj]xanthenes under solvent-flee conditions

A simple and efficient procedure for the preparation of aryl- 14-H-dibenzo [aj]xanthenes by a one-pot condensation reaction of 2-naphthol and aryl aldehydes, in the presence of silica supported sodium hydrogen sulfate （NaHSO4/SiO2） as a catalyst and in the absence of solvent has been developed. The present method offers several advantages such as excellent yields, short reaction time （10-30min）, mild condition, simple work-up, and the use of a cheap and environmentally friendly catalyst with remarkable reusability.     

Iodine Catalyzed Microwave-Assisted Synthesis of 14-Aryl（Alkyl）-14H-dibenzo[a,j]xanthenes

A straightforward and effective procedure for the synthesis of 14-aryl（alkyl）-14H-dibenzo[aj]xanthenes was described using a catalytic amount of molecular iodine under microwave irradiation to afford the corresponding xanthenes in good yields.     

H_5PW(10)V_2O_(40)催化高效环保合成14-芳基-14H-二苯并[a,j]氧杂蒽(英文)

A rapid and efficient procedure for the preparation of various aryl-14H-dibenzo[a,j]xanthenes was reported.The method developed produced excellent yields via one-pot condensation of β-naphthol with various aryl-aldehydes in the presence of Keggin vanadium substituted heteropolyacid,H5PW10V2O40,as catalyst under solvent free conditions.The present methodology therefore offered several advantages but not limited to excellent yields(82%-98%),short reaction times(30-50 min),mild reaction conditions,simple work-up,as well as the utilization of cheap and environmentally benign catalyst in the absence of organic solvents.     

H5PW（10）V2O40催化高效环保合成14-芳基-14H-二苯并[a,j]氧杂蒽（英文）

A rapid and efficient procedure for the preparation of various aryl-14H-dibenzo[a,j]xanthenes was reported.The method developed produced excellent yields via one-pot condensation of β-naphthol with various aryl-aldehydes in the presence of Keggin vanadium substituted heteropolyacid,H5PW10V2O40,as catalyst under solvent free conditions.The present methodology therefore offered several advantages but not limited to excellent yields(82%-98%),short reaction times(30-50 min),mild reaction conditions,simple work-up,as well as the utilization of cheap and environmentally benign catalyst in the absence of organic solvents.     

The Selective Reduction of 4-Propylthio-2-nitroaniline with CO Using Ru3（CO）12／PEDPA Complex as Catalyst

The Ru3(CO)12/PEDPA complex was firstly applied in the CO selective reduction of 4-propylthio-2-nitroaniline.The effects of reaction temperature,the pressure of CO and concentration of catalyst on the reduction were investigated.Under the optimum conditions of T=140℃, Pco=5.0MPa and substrate/catalyst=300(molar ratio),the conversion and selectivity were 70% and 98%,respectively.After simple phase separation,the catalyst could be recycled.     

Fe（HSO4）3： An efficient,heterogeneous and reusable catalyst for the synthesis of 14-aryl- or alkyl- 14H-dibenzo[a,j]xanthenes

Fe（HSO4）3 has been used as an efficient and recyclable catalyst for the one-pot synthesis of 14-aryl- or alkyl-14Hdibenzo[aj]xanthene derivatives by the reaction of 2-naphtol and aldehydes. Different types of aromatic and aliphatic aldehydes are used in the reaction and in all cases the products were obtained in good to excellent yields.     

Silica supported sodium hydrogen sulfate(NaHSO4/SiO2): A mild and efficient reusable catalyst for the synthesis of aryl-14-H-dibenzo[a,j]xanthenes under solvent-free conditions

A simple and efficient procedure for the preparation of aryl-14-H-dibenzo[a,j]xanthenes by a one-pot condensation reaction of 2-naphthol and aryl aldehydes,in the presence of silica supported sodium hydrogen sulfate(NaHSO_4/SiO_2)as a catalyst and in the absence of solvent has been developed.The present method offers several advantages such as excellent yields,short reaction time (10-30 min),mild condition,simple work-up,and the use of a cheap and environmentally friendly catalyst with remarkable reusability.     

H14[NaP5W29MoO110]: a Novel and Useful Catalyst for Aminolysis of Epoxides with Amines under Solvent-Free Conditions

A simple and efficient method has been developed for the synthesis of β-amino alcohols by ring opening of epoxides in the presence of a catalytic amount of H14[NaP5W29MoO110] at room temperature under solvent-free conditions. The reaction works well for both aromatic and aliphatic amines.     

Sodium Hydrogen Sulfate as Effective and Reusable Heterogeneous Catalyst for the One-pot Preparation of 14H-[(Un)substituted phenyl]-dibenzo[a,j]xanthene Leuco-dye Derivatives

NaHSO₄•H₂O has been used as an efficient catalyst for the one-pot preparation of 14H-[(un)substituted phenyl]-dibenzo[a,j]xanthene leuco-dye derivatives by condensation of β-naphthol with substituted benzaldehydes under microwave and thermal conditions. This method has the advantages of high yields, a green reaction, an efficient and cost-effective method, simple procedures, short reaction time, and easy workup.     

Three component reactions：An efficient and green synthesis of 3, 4-dihydropyrimidin-2-(1H)-ones and thiones using silica gel-supported L-pyrrolidine-2-carboxylic acid-4-hydrogen sulfate

An environmentally benign aqueous protocol for the synthesis of 3,4-dihydropyrimidin-2-(1H)-ones and thiones promoted by a green catalyst,silica gel-supported L-pyrrolidine-2-carboxylic acid-4-hydrogen sulfate,has been developed.The use of nontoxic,thermally stable and inexpensive amino acid catalyst makes the process simple with minimal amount of chemical waste.Compared with classical Biginelli reaction conditions,this new method has the advantages of high yields and simple workup procedures.     

Oxalic acld as a catalyst for efficient synthesis of bis-(indolyl)methanes,and 14-aryl-14H-dibenzo[a,j]xanthenes in water

A simple,efficient,and environment benign route was developed for the preparation of bis-(indolyl)methanes and 14-aryl-14H-dibenzo[a,j]xanthenes from condensation of various aromatic aldehydes or ketones with indole,and 2-naphthol,respectively,using oxalic acid catalyst in aqueous medium.Use of cheap and easily available catalyst,better yields and simple reaction protocol are the advantages of the present method.     

Green catalytic synthesis of 14-aryl-14H-dibenzo[a,j]xanthenes using recyclable mesoporous zirconia modified with tungstophosphoric acid

Abstract

A simple and efficient procedure has been developed for the preparation of aryl-14H-dibenzo[a,j]xanthenes by a one-pot condensation of 2-naphthol and aryl aldehydes, in the presence of mesoporous zirconia modified with tungstophosphoric acid (ZrTPA60B_T100), to be used as a heterogeneous catalyst in a solvent-free medium using conventional heating. The present approach offers the advantages of clean reaction, simple methodology, short reaction time, and high yield. The reaction work-up is very simple and the catalyst can be easily separated from the reaction mixture and reused several times in subsequent reactions without appreciable loss of the catalytic activity.     

Silica Gel‐Supported Polyphosphoric Acid (PPA/SiO2): An Efficient and Reusable Heterogeneous Catalyst for Facile Synthesis of 14‐Aryl‐14H‐dibenzo[a,j]xanthenes under Solvent‐free Conditions

A simple, efficient and green method for the synthesis of 14‐aryl‐14H‐dibenzo[a,j]xanthenes by a one‐pot condensation reaction of β‐naphthol and aryl aldehydes using silica gel‐supported polyphosphoric acid (PPA/SiO₂), an effective and reusable catalyst, under solvent‐free conditions is described. The present methodology offers several advantages, such as a simple procedure with an easy work‐up, short reaction times, high yields, and the absence of any volatile and hazardous organic solvents.     

Synthesis of 14‐{[(Un)substituted phenyl] or alkyl}‐14H‐dibenzo[a,j]xanthenes Using Yb(OTf)3 as an Efficient Catalyst under Solvent‐free Conditions

A series of 14‐{[(Un)substituted phenyl] or alkyl}‐14H‐dibenzo[a,j]xanthenes were prepared under solvent‐free conditions by Yb(OTf)₃ catalyzed condensation reactions of β‐naphthol with various aldehydes. The process presented here is operationally simple, environmentally benign and has good to excellent yields. Furthermore, the catalyst can be recovered conveniently and reused efficiently.     

Synthesis of 14-aryl or alkyl- 14H-dibenzo[a,j]xanthenes promoted by Mg(HSO4)2

14-Aryl or alkyl-14H-dibenzo[a,j]xanthenes were prepared by condensation of 2-naphthol and aldehydes in the presence of Mg（HSO₄）₂ as an efficient,cheap,readily available and eco-friendly catalyst.This procedure has the advantages of high yields,easy work-up,short reaction times,and green conditions.     

Metal free Lewis acid promoted one-pot synthesis of 14-aryl-14H dibenzo [a,j] xanthenes and their simple biological evolution

A green, competent one-pot synthesis of 14-aryl 14H-dibenzo [a,j] xanthene and its bio-computational studies are reported. Target compounds are prepared by the condensation of 2-naphthol with benzaldehyde and its substituents using metal free benzyltrimethylammonium tribromide (BTMA-Br₃) catalyst under solvent free thermal and microwave conditions. This technique has more advantages such as high yield, a clean procedure, low reaction time, simple workup and mild Lewis organo acid catalyst.     

N‐Bromosuccinimide (NBS): A Novel and Efficient Catalyst for the Synthesis of 14‐Aryl‐14H‐dibenzo[a,j]xanthenes under Solvent‐Free Conditions

A novel procedure for the synthesis of 14‐aryl‐14H‐dibenzo[a,j]xanthenes through one‐pot condensation of naphthalen‐2‐ol with arenecarbaldehydes in the presence of N‐bromosuccinimide (NBS) as catalyst under solvent‐free conditions is described.     

An efficient and eco-friendly synthesis of 14-aryl-14H-dibenzo[a,j]xanthenes using H4[SiW12O40] as a heterogeneous and reusable catalyst under solvent-free conditions

A simple and efficient catalytic protocol for the synthesis of 14-aryl-14H-dibenzo[a,j]xanthenes via the one-pot condensation ofβ-naphthol and aryl aldehydes using silicotungstic acid(H₄[SiW₁₂O₄₀]) is reported.The present method offers several advantages such as high to excellent yields,short reaction times,recovery and reusability of catalyst,mild reaction conditions and easy workup procedures.     

BTADCI Promoted One‐pot Synthesis of 14‐aryl‐14H‐dibenzo [a,j] Xanthenes

A convenient eco‐friendly one‐pot synthesis of 14‐aryl‐14H‐dibenzo [a, j] xanthenes were developed by the condensation of aromatic aldehydes and β‐naphthol with BTADCI (Benzyltrimethylammonium dichloroiodate) as catalyst under solvent free conditions and microwave irradiation with much more rate accelerations and afford very good yields. Developed protocols involve mild reaction conditions, simple isolation of derivatives with inexpensive reagents.