Facile and Selective Synthesis of 4‐Methyl‐ and 4‐Phenylthiosemicarbazide (=N‐Methyl‐ and N‐Phenylhydrazinecarbothioamide) Derivatives of Benzil (=1,2‐Diphenylethane‐1,2‐dione)

A selective synthesis of 4‐methylthiosemicarbazide (=N‐methylhydrazinecarbothioamide; 4a ) derivatives by reaction with benzil (=1,2‐diphenylethane‐1,2‐dione; 3 ) is described. The reaction conditions determined the condensation product formed. The most important factor was the acid used: in the presence of conc. HCl solution, the open‐chain 2 : 1 compound 1a was exclusively obtained, whereas in the presence of 2M HCl, the cyclic 1 : 1 condensation product 2a was formed. The alcohol used, the presence of H₂O, and the time of heating were additional crucial factors. The new cyclic compound 2a with a MeO group was exclusively formed when working under high‐dilution conditions. The reaction with the 4‐phenyl derivative 4b gave new cyclic compounds as the major products under all conditions used (Scheme).     

Copper(II)‐Catalyzed Synthesis of N‐Substituted‐3‐amino‐4‐cyano‐isoquinoline‐1(2H)‐ones by the Reaction of N‐Substituted‐2‐iodobenzamides with Malononitrile

A novel Cu(OAc)₂·H₂O catalyzed coupling reaction of N‐substituted‐2‐iodobenzamides with malononitrile to afford N‐substituted‐3‐amino‐4‐cyano‐isoquinoline‐1(2H)‐ones is described. The reaction proceeded in DMSO at 90°C for 5 h in nitrogen without external ligands.     

Photocyclodimerization of 5‐Methyl‐2H‐pyran‐3(6H)‐one

The structures of the main products resulting from photocyclodimerization of the title compound 2 and of other 3‐methyl‐substituted ‘oxacyclohex‐2‐en‐1‐ones’ (=dihydropyranones) were determined by X‐ray crystallography. In connection, the ¹³C‐NMR chemical shifts of the cyclobutane C‐atoms of these dimers allow a clear differentiation between head‐to‐head and head‐to‐tail regioisomers, all structurally related to those of isophorone ( 1 ).     

Ultrasound‐Assisted One‐Pot Synthesis of Octahydroquinazolinone Derivatives Catalyzed by Acidic Ionic Liquid [Tbmim]Cl2/AlCl3

Acidic ionic liquid [tbmim]Cl₂/AlCl₃ catalysed an efficient synthesis of octahydroquinazolinone derivatives under ultrasound‐irradiation. This method provides several advantages such as environment benign, high yields and simple work‐up procedure.     

Ultrasound‐Assisted Synthesis of 3‐(Arylamino)‐1‐ferrocenylpropan‐1‐ones

A successful aza‐Michael addition of arylamines to a conjugated enone, acryloylferrocene, has been achieved by ultrasonic irradiation of the mixture of these reactants and the catalyst, i.e., montmorillonite K‐10. This solvent‐free reaction, yielding ferrocene containing Mannich bases, 3‐(arylamino)‐1‐ferrocenylpropan‐1‐ones, considered as valuable precursors in organic synthesis, has been performed by using a simple ultrasonic cleaner. Among 17 synthesized β‐amino ketones, three were new ones, and these were fully characterized by spectroscopic means. X‐Ray crystallographic analysis of three of these crystalline products enabled the insight into the conformational details of these compounds. All compounds were evaluated for their antibacterial activities against six Gram‐positive and five Gram‐negative strains in a microdilution assay. The observed promising antibacterial activity (with a MIC value of 25 μg/ml (ca. 0.07 μmol/ml) as the best result for almost all tested compounds against Micrococcus flavus) seems not only to be compound but also bacterial species‐specific.     

微波辐射下FeCl3·6H2O催化绿色合成3,4-二氢嘧啶-2-酮

在微波辐射下,仅以六水合三氯化铁为催化剂,将芳香醛、β-二羰基化合物和脲(物质的量比为1:1.5:1.5)在无水乙醇中回流,高效地合成了3,4-二氢嘧啶-2-酮,反应时间4～6min,操作简便,环境友好.     

Synthesis of 4‐halo‐2 (5H)‐furanones and their suzuki‐coupling reactions with organoboronic acids. A general route to 4‐aryl‐2 (5 H) ‐furanones

4‐Halo‐2(5H)‐furanones were prepared by the halolactonization of 2,3‐allenoic acids. The subsequent Suzuki coupling reaction of 4‐halo 2(5H)‐furanones with aryl boronic acids was carried out to produce 4‐aryl‐2(5H)‐furanones in excellent yields.     

N-(4-甲基苯甲酰氨基) N’-[5-(2-三氟甲基苯基)-2-呋喃甲酰硫脲的合成、晶体结构测定与生物活性测定

本文首次合成标题化合物N-(4-甲基苯甲酰氨基)-N’-[5-(2-三氟甲基苯基)-2-呋喃甲酰硫脲。化合物(C21H16F3N3O3S, Mr = 447.43)单晶经测定为单斜晶体,空间群为P -1。在晶体中,存在一些分子内和分子间的相互作用,分子间还有C—H···π 的相互作用,这可能导致晶体更稳定的原因。目标产物的结构经IR, H NMR和元素分析测定确证。初步生物活性测试表明,部分化合物对棉花枯萎病、黄瓜灰霉病、苹果轮纹病和棉花炭疽病有较好的选择性杀菌活性;部分目标化合物有较好的除草活性。     

微波辐射下FeCl3•6H2O催化绿色合成3,4-二氢嘧啶-2-酮

在微波辐射下, 仅以六水合三氯化铁为催化剂, 将芳香醛、β-二羰基化合物和脲(物质的量比为1∶1.5∶1.5)在无水乙醇中回流, 高效地合成了3,4-二氢嘧啶-2-酮, 反应时间4～6 min, 操作简便, 环境友好.     

The Synthesis of New Organoselenium Heterocyclic Compounds: 2‐aryl‐4‐phenyl‐5,6,7,8‐tetrahydro‐4H‐selenochromenes

We have explored the reactions of 2‐(3‐oxo‐1‐aryl‐3‐phenylpropyl)cyclohexanone ( 1–3 ) with hydrogen selenide in situ in conditions of acid catalysis, and synthesized new 2‐aryl‐4‐phenyl‐5,6,7,8‐tetrahydro‐4H‐selenochromenes ( 4–6 ).     

Efficient Synthesis of 5‐Carboxanilide‐Dihydropyrimidinones Using Cobalt(II) Nitrate Hexahydrate

5‐Carboxanilide‐dihydropyrimidinone derivatives were synthesized in good yield in a three‐component and efficient process by the condensation reaction of acetoacetanilide, aldehyde and urea/thiourea in the presence of cobalt(II) nitrate hexahydrate as catalyst in ethanol at ambient condition.     

Ultrasound‐Assisted Wittig Reaction: A Short,Efficient Synthesis of 2‐Methoxy‐6‐Alkyl‐1,4‐Benzoquinones

A short, efficient synthesis of 2‐methoxy‐6‐alkyl‐1,4‐benzoquinones is described. Ultrasound‐assisted Wittig reaction of alkyltriphenyl phosphonium bromides with o‐vanillin in basic aqueous conditions followed by reduction with Na/n‐BuOH gave 2‐methoxy‐6‐alkylphenols. Oxidation of 2‐methoxy‐6‐alkylphenols with Fremy's salt produced the title compounds.     

Synthesis of 4-(4-Methylsulfonylphenyl)-3-phenyl-2(3H)-thiazole Thione Derivatives as New Potential COX-2 Inhibitors

Synthesis of novel 4-（4-methylsulfonylphenyl）-3-phenyl-2（3H）-thiazole thione derivatives with functionalized diarylheterocycle pharmacophore as potential COX-2 inhibitors was described. The title compounds were synthesized by cyclocondensation of corresponding dithiocarbamate and 2-bromo-1-（4-methylsulfonylphenyl）ethanone, followed by dehydration with H2SO4. All of the target compounds were characterized by ^1H NMR, IR and mass spectral data.     

CuBr/Et3N‐Promoted Reactions of 2‐Aminobenzamides and Isothiocyanates: Efficient Synthesis of Novel Quinazolin‐4(3H)‐ones

A series of novel quinazolin‐4(3H)‐one derivatives were efficiently synthesized starting from isatoic anhydride. First, reaction of isatoic anhydride and amines in H₂O at room temperature afforded 2‐aminobenzamides. Then, CuBr/Et₃N promoted reaction of 2‐aminobenzamides and different aryl isothiocyanates in DMF at 80° afforded the title compounds in good yield.     

A Novel One‐Pot Synthesis of Fully Substituted Thiophen‐2(3H)‐ones Using N,N‐Disubstituted Thioamides

A new one‐step synthesis of highly substituted thiophen‐2(3H)‐one derivatives was developed. 2‐Aryl‐1‐(morpholin‐4‐yl)ethanethiones were reacted with 2‐chloro‐2‐phenylacetyl chloride in DMF in the presence of a base to give the title compounds in moderate‐to‐good yields.     

Synthesis of 6‐Aminoindolo[2,1‐a]isoquinoline‐5‐carbonitriles by the Cu‐Catalyzed Reaction of 2‐(2‐Bromophenyl)‐1H‐indoles with CH2(CN)2

A series of 6‐aminoindolo[2,1‐a]isoquinoline‐5‐carbonitriles 4 have been prepared by treatment of 2‐(2‐bromophenyl)‐1H‐indoles 1 , available from 1‐(2‐bromophenyl)ethanones or 1‐(2‐bromophenyl)propan‐1‐ones by using Fischer indole synthesis, with propanedinitrile in the presence of a catalytic amount of CuBr and an excess of K₂CO₃ in DMSO at 100°.     

A One‐Pot Biginelli Synthesis of 6‐Unsubstituted 5‐Aroylpyrimidin‐2(1H)‐ones and 6‐Acetyl‐1,2,4‐triazin‐3(2H)‐ones

The three‐component Biginelli‐like cyclocondensation reaction of enamines 1 , urea, and aldehydes in dioxane/acetic acid efficiently afforded the corresponding 6‐unsubstituted 3,4‐dihydropyrimidin‐2(1H)‐ones 2 in good yields (Scheme 1, Table). The corresponding reaction of azaenamine (=hydrazone) 7 with benzaldehyde and urea afforded 6‐acetyl‐1,2,4‐triazin‐3(2H)‐ones in good yields (Scheme 3).     

Synthesis of Some Quinazoline‐2(1H),4(3H)‐dione Derivatives

Several quinazoline‐2(1H),4(3H)‐dione derivatives were synthesized from pyrimidine‐2(1H),4(3H)‐dione derivative.     

The Synthesis of (4E)‐N‐(4‐chlorophenyl)‐5‐substituted‐2‐diazo‐3‐oxopent‐4‐enoic Acid Amides

The (4E)‐N‐(4‐chlorophenyl)‐5‐(3‐chlorophenyl)‐2‐diazo‐3‐oxopent‐4‐enoic acid amides 5a˜j were synthesized with N‐(4‐chlorophenyl)‐2‐diazo‐3‐oxobutyramide 4 from p‐chloroaniline and various arylaldehydes. The yielded products 5a˜j were investigated with NMR, MS, IR, and X‐ray crystallographic techniques.     

Copper(II)‐Catalyzed Tandem Synthesis of Substituted 3‐Methyleneisoindolin‐1‐ones

An efficient strategy for the synthesis of a variety of 3‐methyleneisoindolin‐1‐ones has been developed. The reaction proceeded from coupling of 2‐iodobenzamides (or 2‐bromobenzamides) and terminal alkynes via Cu(OAc)₂·H₂O/2,2′‐biimidazole catalyzed in DMF at 60°C and subsequent additive cyclization produced substituted 3‐methyleneisoindolin‐1‐ones in good to excellent yields.