Room-Temperature Bismuth-Catalyzed Bis-arylation of Carbonyl Compounds with Aryl Ethers and Phenols

Using Bi2（SO4）3 as the catalyst and TMSCl as the additive, a wide variety of aldehydes, ketones, and acetals were smoothly condensed with aryl ethers at room temperature to provide the corresponding diarylmethanes and triarylmethanes selectively in good to excellent yields.     

基于5-(2-羧基苯基)吡啶-3-甲酸配体的镍(Ⅱ)和锌(Ⅱ)配位聚合物的合成、晶体结构、催化及抗磨性质

采用水热方法,选用5-(2-羧基苯基)吡啶-3-甲酸配体(H₂cpna)与1,2-二(4-吡啶基)乙烷(dpea)或1,2-二(4-吡啶基)乙烯(dpey)分别与NiCl₂·6H₂O和ZnCl₂在160℃下反应,合成了2个三维配位聚合物{[Ni(μ₃-cpna)(μ-dpea)_0.5]·H₂O}_n (1)和{[Zn(μ₃-cpna)(μ-dpey)_0.5]·H₂O}_n (2),并对其结构、催化和摩擦性质进行了研究。研究表明,在室温条件下化合物2在Knoevenagel缩合反应中显示出较好的催化活性。同时,2在聚α-烯烃合成润滑剂中显示出有效的抗磨性能。     

膦酰肽和膦酰酯肽的汇聚式合成

本文首先介绍了膦酰肽的分类、结构特征以及膦酰肽的主要合成方法,然后详细介绍了类Mannich反应在合成氨基膦酸衍生物中的应用,并介绍了以类Mannich反应为关键步骤通过汇聚式的方法合成膦酰肽、膦酰酯肽、次膦酰肽、次膦酰酯肽、磺酰膦酰杂交肽的研究进展.汇聚式的合成方法具有原料简单、合成步骤少、原子经济性好等优点.     

Synthesis of amine-phenol ligands in water – a simple demonstration of a hydrophobic effect

Abstract

The synthesis in water of a series of tetradentate amine-phenol ligands derived from formaldehyde, 2,4-disubstituted phenols and amines is presented. These molecules, which are used in catalyst development, include 4,6-di-alkyl-2-bis(2-methoxyethyl)aminomethylphenols and 4,6-di-tert-amyl-2-bis(3-(dimethylamino)propyl)aminomethylphenols. Yields were generally greater than reactions performed in methanol and near quantitative for hydrophobic phenols.     

Organic Reactions in Ionic Liquids: Ionic Liquid Ethylammonium Nitrate–Promoted Knoevenagel Condensation of Meldrum's Acid With Aromatic Aldehydes

The Knoevenagel condensation of Meldrum's acid with aromatic aldehydes proceeded efficiently in a reusable ionic liquid, ethylammonium nitrate, at room temperature in the absence of any catalyst with high yields.     

Synthesis of 1,4‐Diaryl‐piperazine‐2,5‐diones: New Behavior of N,N‐Dimethylformamide Dimethyl Acetal (DMFDMA)

Reactions of chloroacetamides (5) with N,N‐dimethylformamide dimethyl acetal gave 1,4‐diaryl‐piperazine‐2,5‐diones 11a–e in good yield, rather than 1,5‐diaryl‐3,7‐dimethoxy‐1H,5H‐[1,5]diazocine‐2,6‐diones (9a–e).     

Atom-Efficient,Solvent-Free,Green Synthesis of Chalcones by Grinding

An improved Claisen–Schmidt condensation reaction of methyl ketones and aromatic aldehydes can be achieved by grinding at room temperature in the absence of solvents. This process is simple, efficient, economical, and environmentally benign compared to classical reactions.     

Starch?Sulfuric Acid (SSA) as Catalyst for a One‐Pot Synthesis of 1,5‐Diaryl‐1H‐pyrazoles

Protocols with starch? sulfuric acid (SSA) as reusable catalyst for the synthesis of aryl‐1H‐pyrazoles are described. SSA acted as an efficient and environmentally friendly catalyst for the regioselective condensation of Baylis? Hillman adducts 1 with phenylhydrazine hydrochloride leading to the new 1,5‐diaryl‐1H‐pyrazole 2a – 2e in excellent yields (Scheme and Table 1).     

Stereocontrolled Transformations of trans α,β‐Aziridine Aldehydes toward Different Amino Hydroxylated Structures

The stereocontrolled condensation of methyl ketones to trans α,β‐aziridine aldehydes creates functionalized aldols, valuable precursors for different amino hydroxylated structures, such as amino alcohols, amino diols, α‐tetrahydrofuryl amides, and α‐furyl amides.     

Novel,Simple, and Efficient Synthesis of 3-(2-(5-(Benzylideneamino)-3-phenyl-1H-pyrazol-1-yl)thiazol-4-yl)-4-hydroxy-6-methyl-2H-pyran-2-one Derivatives via a One-Pot,Four-Component Condensation Reaction

The synthesis of 3-(2-(5-(benzylideneamino)-3-phenyl-1H-pyrazol-1-yl)thiazol-4-yl)-4-hydroxy-6-methyl-2H-pyran-2-one derivatives was achieved through a one-pot, four-component reaction involving condensation of 3-(2-bromoacetyl)-4-hydroxy-6-methyl-2H-pyran-2-one, thiosemicarbazide, phenacylcyanaide, and various aryl aldehydes in dry alcohol and few drops of acetic acid under reflux condition. This four-component reaction has some advantages such as ease of handling, good yields, and easy workup. All structures of newly prepared compounds were confirmed by analytical and spectral data.