CuI-catalyzed Coupling Reactions of Aryl Iodides with Amides Using L-Proline and KF/Al2O3

An efficient experimentally simple and inexpensive catalyst system for the selective amidation of aryl iodides using 15 mol% of CuI as catalyst, 15 mol% of L-proline as ligand and KF/Al2O3 as a base in toluene is described.     

Synthesis and Crystal Structure of O,O-Dimethyl-N-(β-triphenylgermanyl)propionyl-α- aminobenzylphosphonates

1 INTRODUCTION Both β-triphenylgermanyl propionic acid and its derivatives have recently attracted a great deal of attention due to their strong anti-inflammatory as well as antibiotic properties[1~3]. α-aminobenzyl- phosphonates are also reported to exhibit diverse biological activities[4~6].It is conceivable that the incorporation of the two moieties into one structural unit might produce an unexpected effect on the activity of such a compound, and the studies on this type of novel s…     

Hafnium(Ⅳ) bis(perfluorooctanesulfonyl)imide complex catalyzed direct amidomethylation for the synthesis of 1-(arylamido)-methyl-2-naphthols in fluorous medium

Hafnium(Ⅳ) bis(perfluorooctanesulfonyl)imide complex is found to be an efficient catalyst for the multicomponent condensation ofβ-naphthol,aromatic aldehydes and urea or amides in perfluorodecalin to afford the corresponding substituted amidomethyl naphthols in good yields.The remarkable features of this new procedure are high yields,shorter reaction times, reusability of catalyst and simple work-up procedures.     

Synthesis of (3R, 4R)-1, 2-Divinylglycol and its Unsymmetrical Derivatives : An Application to the Synthesis of R-(+)-α-Lipoic Acid

ABSTRACT

The synthesis of (3R, 4R)-divinylglycol (1) and some of its unsymmetrical derivatives has been described starting from D-mannitol. I has been converted into R-(+)-α-lipoic acid.     

A Green Synthesis of 2-Ethylanthraquinone by Dehydration of 2-(4''''-ethylbenzoyl) benzoic Acid over Solid Acid Catalysts

2-EAQ is an important intermediate for the synthesis of hydrogen peroxide, pharmaceu- ticals, pesticides, and dyes. With the increasing demand for hydrogen peroxide, it needs to enhance the yields of 2-EAQ. However, in the conventional process, concentrated H2SO41-2 is employed as the catalyst in the dehydration of BE acid for the synthesis of 2-EAQ, which produces a series of environmental impacts and safety concerns. For these reasons, a substitute process, which has little or no hazard…     

Synthesis and Crystal Structure of α-(3-Phenylureido)-α-(2,4-Dichlorophenyl) Methyl Phenylphosphinic Acid

1INThODUCT1ONInaprevi0uspaPer"',wereP0rtedthesyntheses0fsome1,3,4-diazaphospho-lidin-2-thione-4-oxidesandtheirhighselectiveherbicidalactivity.Althoughtherewereseveralreportsaboutthedesulphurisationofsomestraightchainthioureaderiva-tivest2'31,uptonow,thedesulphurisationreactionofcyclicthioureaderivativesutiliz-ingAgNO,-H,Osystemhasnotbeenstudied.InthispaPer,thedesulphurisation0fcis-3,4-diphenyl-5-(2,4-dichlorophenyl)-1,3,4-diazaphOSpholidin-2-thione-4-oasthecyclicsubstrateisrep0rtedfort…     

First Total Synthesis of 3α,4α-Oxidoagarofuran and (-)-3β,4α-Dihydroxy-β-dihydroagarofuran

The first stereoselective total synthesis of (–)-3β, 4α-dihydroxy-β-dihydroagarofuran (1) and 3α, 4α-oxidoagarofuran (2) has been described. The key step is the epoxidation of α-agarofuran (6) with dimethyldioxirane.     

Synthesis and characterization of nanocrystalline α-Al2O3 using Al and Fe2O3 (hematite) through mechanical alloying

In this present work, the synthesis of nanocrystalline α-Al₂O₃ using pure aluminum (Al) and Fe₂O₃ (hematite) as the precursors by mechanical alloying technique has been studied. The formation of α-Al₂O₃ nanocrystallites occurs during the solid-state reaction and through the reduction treatment. Also in this paper, effects of milling time on particle size and the lattice strain nanocrystalline α-Al₂O₃ have been investigated. Obtained powders were evaluated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), differential thermal analysis (DTA), thermal gravimetric analysis (TGA) and X-ray diffraction (XRD). The obtained results indicated that a reduction reaction was completed after 2 h milling in a planetary mill. The crystallite size of obtained α-alumina (α-Al₂O₃) was in general about 12 nm. Finally, the results showed appropriate homogeneity and dispersion of related nanocrystalline.     

Synthesis, Structure and Physical Property of a New 3D Lead Coordination Polymer:[Pb2(L)2(dea)]n·nH2O

A new 3D Pb(Ⅱ) coordination polymer [Pb2(L)2(dea)]n·nH2O has been hydrothermally prepared by using the long flexible decanedioic acid (H2dea) and the N-donor chelating ligand 2-(1H-l,3,7,8-tetraazacyclopenta[l]phenanthren-2-yl)naphthol (HL). Single-crystal X-ray determi- nation shows that the complex crystallizes in the monoclinic system, space group C2/c with a = 25.453(5), b = 7.5035(15), c = 27.340(6),β= 114.84(3)°, V = 4738.6(16)3, Z = 8, C28H22N4O4Pb, Mr = 685.69, Dc = 1.922 g/cm3, F(000) = 2656, μ(MoKa) = 7.166 mm-1, R = 0.0282 and wR = 0.0687. Two L ligands bridge two Pb(Ⅱ) atoms to form a dimmer, and the neighboring dimers are further linked by the dea ligands to yield a 3D structure. The IR and TG of the compound have been investigated in detail.     

聚合物负载磺酸催化的三组分反应合成1-酰胺烷基-2-萘酚

聚合物负载磺酸，一种环境友好的固体酸催化剂，可以有效地催化2-萘酚、脲或酰胺和醛的三组分“一锅”反应生成1-酰胺烷基-2-萘酚。该方法得率高，操作简单。     

Alumina Perchloric Acid (Al 2 O 3 -HClO 4 ) as an Efficient Heterogeneous Catalyst for Modified Preparation of Trimethylsilyl Ethers

A highly efficient and mild procedure for the trimethylsilylation of a wide variety of alcohols, including primary, benzylic, secondary, hindered secondary, tertiary, phenols, and oximes with hexamethyldisilazane (HMDS) using alumina perchloric acid (Al ₂ O ₃ -HClO ₄ ) as recyclable heterogeneous catalyst in excellent yields with short reaction times (3?65 min) under ambient conditions is described.     

Silica supported perchloric acid (HClO4-SiO2): an efficient and recyclable heterogeneous catalyst for the one-pot synthesis of amidoalkyl naphthols

An efficient and direct protocol for the preparation of amidoalkyl naphthols employing a multi-component and one-pot condensation reaction of 2-naphthol, aromatic aldehydes, and acetonitrile or acetamide in the presence of silica supported perchloric acid under solvent, solvent-free, and microwave irradiation conditions is described. The present protocol with HClO₄-SiO₂ catalyst is superior to the recently reported catalytic methods. It is noteworthy that 1-amidomethyl-2-naphthols can be converted into important ‘drug like’ 1-aminomethyl-2-naphthol derivatives by amide hydrolysis.     

磷钼酸：一种有效的催化三组分反应合成1-酰胺烷基-2-萘酚的Keggin型杂多酸

磷钼酸,一种环境友好的杂多酸催化剂,可以有效地催化2-萘酚、脲或酰胺和醛的三组分“一锅”反应生成1-酰胺烷基-2-萘酚。该方法得率高,操作简单。     

Silica‐supported Perchloric Acid Catalyzed One‐pot Synthesis of 1,4‐Dihydropyridines

An environmentally friendly and highly efficient procedure for the preparation of 1,4‐dihydropyridines by the reaction between α,β‐unsaturated aldehydes, aromatic amines and β‐keto esters in the presence of silica supported perchloric acid is described.     

N-Bromosuccinimide Catalyzed One-pot and Rapid Synthesis of Acetamidobenzyl Naphthols under Mild and Solvent-free Conditions

An efficient, facile and expeditious direct protocol for the preparation of acetamidobenzyl naphthols employing a multi-component and one-pot condensation reaction of 2-naphthol, benzaldehydes, and acetamide in the presence of N-bromosuccinimide (NBS) under thermal and microwave irradiation conditions has been described. The present protocol with NBS catalyst is convincingly superior to the recently reported catalytic methods.     

Synthesis of α,β-unsaturated oxathiolanes

The formation of α,β-unsaturated oxathiolanes 2 from α,β-unsaturated carbonyl derivatives was achieved selectively and in high yields using the heterogeneous catalyst APSG·HCl.     

Synthesis of Novel α‐(Acyloxy)‐α‐(quinolin‐4‐yl)acetamides by a Three‐Component Reaction between an Isocyanide,Quinoline‐4‐carbaldehyde,and Arenecarboxylic Acids

Novel α‐(acyloxy)‐α‐(quinolin‐4‐yl)acetamides were synthesized by the Passerini three‐component reaction between an isocyanide, quinoline‐4‐carbaldehyde, and arenecarboxylic acids in H₂O. The reactions were carried out in one pot at room temperature with quantitative yields.     

Nanomagnetic‐supported Sulfonic Acid: Simple and Rapid Method for the Synthesis of α,α′‐Bis‐(substituted‐benzylidene) Cycloalkanones

Nanomagnetic‐supported sulfonic acid is found to be a powerful and reusable heterogeneous catalyst for the rapid synthesis of α,α′‐bis‐(substituted‐benzylidene)cycloalkanones under conventional heating and solvent free conditions. High yield, simple work up and easy recovery of the catalyst are the most obvious advantages of this procedure.     

Multi‐wall carbon nanotube supported Co (II) Schiff base complex: an efficient and highly reusable catalyst for synthesis of 1‐amidoalkyl‐2‐naphthol and tetrahydrobenzo[b]pyran derivatives

An immobilized Co (II) Schiff base complex supported on multi‐wall carbon nanotubes was synthesized and characterized using Fourier transform infrared spectroscopy, X‐ray diffraction, scanning electron microscopy, energy‐dispersive X‐ray spectroscopy , thermogravimetric analysis and inductively coupled plasma mass spectrometry. It was shown that the supported complex is a facile, eco‐friendly, recyclable, reusable and green catalyst for three‐component condensation of 2‐naphthol and acetamide with various aldehydes for the synthesis of 1‐amidoalkyl‐2‐naphthol derivatives under solvent‐free conditions. Also, in a further study, the catalytic application was studied in the synthesis of tetrahydrobenzo[b ]pyran derivatives via the condensation reaction of malononitrile and dimedone with several aromatic aldehydes. The procedures suggested here for the synthesis of 1‐amidoalkyl‐2‐naphthol and tetrahydrobenzo[b ]pyran derivatives offer several advantages, such as stability, recyclability and eco‐friendliness of the catalyst, simple experimental conditions, short reaction times, high to excellent yields and easy work‐up.