Xiaobi Jing

Novel Method for the Synthesis of 1,3,5‐Triarylbenzenes from Ketones

Abstract Treatment of aryl ketones with p‐toluenesulfinic acid and a catalytic amount of tin tetrachloride anhydrous (5%) in 1‐pentanol gives good yields of 1,3,5‐triarylbenzenes.

Rapid One‐Pot Preparation of 2‐Substituted Benzimidazoles from Esters using Microwave Conditions

Abstract A high‐yielding one‐pot procedure for the generation of 2‐substituted benzimidazoles first from esters using a microwave procedure is described.

NAIO4-CATALYZED ONE-POT SYNTHESIS OF DIHYDROPYRIMIDINONES AT ROOM TEMPERATURE UNDER SOLVENT-FREE CONDITIONS

Sodium periodate efficiently catalyzed the three-component Biginelli reaction of an aldehyde, α β-keto ester or β-keto ketone, and urea or thiourea at room temperature under solvent-free conditions and afforded the corresponding 3,4-dihydropyrimidine-2-(1H)-ones in excellent yields.

Novel One-Pot Procedure for the Synthesis of 1,2-Diketones

Abstract A simple and convenient one-pot procedure is reported for the synthesis of 1,2-diketones from corresponding benzoin-type condensation reaction of aromatic aldehydes in water with N,N-dialkylbenzimidazolium salt as condensation catalyst and ferric chloride as oxidizing reagent.

PdO-Catalyzed Synthesis of Tricyclic Compounds Using Biginelli-Like Reaction

Abstract An efficient method has been successfully developed for the synthesis of oxygen-bridged pyrimidine tricyclic derivatives from salicylaldehyde, ethyl acetoacete, and urea catalyzed by PdO in very good yield. A series of different oxygen-bridged pyrimidine tricyclic derivatives has been synthesized, in which two compounds’ x-ray crystal structure were obtained.

Organic Catalytic Multicomponent One-Pot Synthesis of Highly Substituted Pyrroles

Abstract A multicomponent synthesis of highly substituted pyrroles catalyzed by thiazolium salts has been disclosed. The reaction employs an acyl anion conjugate addition reaction of aldegyde and unsaturated ketones to generate 1,4-dicarbonyl compounds in situ. The subsequent addition of various amines promotes a Paal–Knorr reaction, affording the desired pyrrole nucleus in an efficient one-pot process.

ZN(OAC)2 CATALYZED MICROWAVE IRRADIATED SYNTHESIS OF SUBSTITUTED THIENO[2, 3-D]PYRIMIDIN-4(3H)-ONE

Different Lewis acids were screened to catalyze the reaction of 2-amino-thiophene-3-carboxylate, orthoformate and aryl amine to form 2-substituted thieno[2,3-d]pyrimidin-4(3H)-one. Zn(OAc)2 was demonstrated to efficiently catalyze the reaction. 20 substituted thieno[2,3-d]pyrimidines were synthesized by adding 0.5% mol Zn(OAc)2 as catalyst under microwave irradiation.

One Step of Palladium Catalyzed Benzodioxane Ring C–O Bond Formation, Synthesis of Isoamericanol A and Isoamericanin A

Abstract A number of benzodioxane compounds were synthesized using the palladium‐catalyzed etherification of aryl halides by employing triphenylphosphane ligands. This method was used as key step in the synthesis of two natural products isoamericanol A and isoamericanin A.

Synthesis of Di(6-aminouracil-5-yl)-arylmethane: A New Product of the Reaction of 6-Aminouracil with Aldehyde

Abstract In this article, a new result of the reaction of 6-aminouracil with aldehyde catalyzed by BF3 and aniline is established, which gives a new strategy for the synthesis of di(6-aminouracil-5-yl)-arylmethane. The simple and convenient synthetic procedure and formation of di(6-aminouracil-5-yl)-arylmethane render this method very useful in synthetic and medicimal chemistry. GRAPHICAL ABSTRACT

ONE-POT SYNTHESIS OF POLYSUBSTITUTED IMIDAZOLES FROM ARYLALDEHYDES IN WATER CATALYZED BY NHC USING MICROWAVE IRRADIATION

ABSTRACT A simple, high yielding synthesis of tri (3a-i) and tetrasubstituted (4a-g) imidazols from aldehydes is described. The cornerstone of this methodology involves the condensation of NH 4 OAc, substituted aldehydes, and benzoin, which is synthesized in situ from aldehydes catalyzed by N-heterocyclic carbine (NHC), under microwave irradiation in water to afford trisubstituted imidazoles (3a-i). If arylamine is added in the solution, tetrasubstituted imidazoles (4a-g) can be obtained. Lepidilines B and trifenagrel are also synthesized in high yield using this procedure. All the experiment deta are in agreement with the literature. Keywords: Trisubstituted imidazoles, tetrasubstituted imidazoles, microwave irradiation, Lepidilines B, Trifenagrel, N-heterocyclic carbine (NHC) INTRODUCTION Imidazole ring system is one of the most important substructures found in a large number of natural products and pharmacologically active compounds such as antiulcerative agent cimetidine 1 , the proton pump inhibitor omeprazole