Simple synthesis of a terpenophenol—chlorin conjugate with an amide bond

A terpenophenol with a butylaminomethyl group was synthesized and conjugated to a chlorin macrocycle through formation of an amide bond without using activating reagents. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 561–563, November–December, 2007.     

Weakly Coordinating,Ketone-Directed (η5-Pentamethylcyclopentadienyl)cobalt(III)- and (η5-Pentamethylcyclopentadienyl)rhodium(III)-Catalyzed C−H Amidation of Arenes: A Route to Acridone Alkaloids

The weakly coordinating, ketone-directed, regioselective monoamidation of aromatic ketones, chalcone, carbazole, and benzophenones was achieved by employing high-valent cobalt and rhodium catalysis to access numerous biologically important molecular building blocks. This amidation proceeded smoothly with a variety of ketones and several amidating partners. The application of the products in the synthesis of various heterocycles, including acridones, indoles, quinoline, quinolones, quinolinones, and quinazolines, was also explored. The total synthesis of acridone-based alkaloids, namely, toddaliopsin A, toddaliopsin D, and arborinine, and the formal synthesis of acronycine and noracronycin were also accomplished by applying this method. A mechanistic study revealed this amidation reaction follows a base-assisted intermolecular electrophilic substitution pathway.     

Ligand preferences in ytterbium ions complexation with carboxylate-based metal-organic frameworks

Two coordination polymers of ytterbium were synthesized by employing 4,4′,4″-s-triazine-2,4,6-triyl-tribenzoic acid (H₃TATB), 4,4′,4-benzene-1,3,5-triyl-tribenzoic acid (H₃BTB), and 3,5-pyridinedicarboxylic acid (3,5-PDC) ligands and were characterized by single-crystal X-ray diffraction analysis. Reaction of ytterbium(III) chloride in the presence of H₃BTB and 3,5-PDC ligands gives preferred complexation with the 3,5-PDC ligand, producing [Yb₂(3,5-PDC)(ClO₄)₃][NH(Me)₃] (1). However, under exactly the same reaction conditions, reaction of ytterbium(III) chloride in the presence of 3,5-PDC and H₃TATB resulted in complexation with H₃TATB to form [(CH₃)₂NH₂][Yb₄(TATB)₄(HCO₂)(H₂O)₂]·3H₂O (2). The crystal structure results showed a layered structure for 1 and a metal-organic framework structure for 2. This indicates that the complexation preference of the ytterbium ion is H₃TATB ≥ 3,5-PDC ≥ H₃BTB. Conversely, the uncomplexed ligand in the metal-organic framework (2) is an auxiliary agent during the synthesis, which shows polytopic linker controls crystal properties, to form suitable crystals for single-crystal structure determination. The prepared coordination compounds were used as heterogeneous catalysts in an oxidation amidation reaction with different aldehydes and benzylamine hydrochloride.     

Ir‐Catalyzed C−H Amidation of Aldehydes with Stoichiometric/Catalytic Directing Group

Ir‐catalyzed sp² C?H amidation of aldehydes with various anilines as stoichiometric or catalytic directing groups was accomplished. A wide range of substrates were selectively amidated in good to excellent yields with broad functional group tolerance. The iridacycle complexes were isolated, characterized, and proved as key intermediates. Kinetic studies and Hammett plots provided detailed understandings of this amidation. According to the mechanism, the electron‐rich ArSO₂N₃ was proved effective for intermolecular sp³ C?H amidation.     

多壁碳纳米管负载Cu2O和CuI催化剂上芳醛与2-氨基吡啶氧化酰胺化反应：Cu（I）物种的催化作用

采用浸渍法制备了多壁碳纳米管(MWCNT)负载的Cu2O和CuI催化剂,并运用粉末X射线衍射、红外光谱、扫描电镜-能量散射谱、透射电镜和NH3程序升温脱附等技术对催化剂进行了表征。结果表明,催化剂中沉积的Cu2O和CuI分别以立方相和γ相存在于MWCNT上,且表现出由弱到强的拉电子(Lewis酸)性能。将催化剂用于催化芳醛与2-氨基吡啶氧化酰胺化反应合成N-(吡啶-2-基)苯酰胺类化合物,产物选择性为100%,收率为50%–95%。 CuI/MWCNT催化剂上产物分离收率性能好于Cu2O/MWCNT,但后者的循环使用性能更好。与共价的CuI相比,离子化的Cu2O与极性的酸活化的MWCNT间具有更适宜的相互作用,这种不同的相互作用可显著影响2-氨基吡啶的氨基对芳醛羰基的亲核进攻速率。     

Repurposing n-butyl stannoic acid as highly efficient catalyst for direct amidation of carboxylic acids with amines

This is the first-time report on the repurposing n-butyl stannoic acid as a catalyst for direct amidation of carboxylic acids with amines. Notably, efficient amidation observed in comparison with all other catalytic methods reported up until now. The protocol has successfully applied to the synthesis of a variety of amides. Moderate reaction parameters, clean amidation with excellent yields of desired amides, ability to tolerate a variety of functional groups, easy product isolation; commercial availability and recyclability of the catalyst are key advantages of the current protocol.     

Cage‐like Copper(II) Silsesquioxanes: Transmetalation Reactions and Structural,Quantum Chemical,and Catalytic Studies

The transmetalation of bimetallic copper–sodium silsesquioxane cages, namely, [(PhSiO_1.5)₁₀(CuO)₂(NaO_0.5)₂] (“Cooling Tower”; 1 ), [(PhSiO_1.5)₁₂(CuO)₄(NaO_0.5)₄] (“Globule”; 2 ), and [(PhSiO_1.5)₆(CuO)₄(NaO_0.5)₄(PhSiO_1.5)₆] (“Sandwich”; 3 ), resulted in the generation of three types of hexanuclear cylinder‐like copper silsesqui‐ oxanes, [(PhSiO_1.5)₁₂(CuO)₆(C₄H₉OH)₂(C₂H₅OH)₆] ( 4 ), [(PhSiO_1.5)₁₂(CuO)₆(C₄H₈O₂)₄(PhCN)₂(MeOH)₄] ( 5 ), and [(PhSiO_1.5)₁₂(CuO)₆(NaCl)(C₄H₈O₂)₁₂(H₂O)₂] ( 6 ). The products show a prominent “solvating system–structure” dependency, as determined by X‐ray diffraction. Topological analysis of cages 1 – 6 was also performed. In addition, DFT theory was used to examine the structures of the Cooling Tower and Cylinder compounds, as well as the spin density distributions. Compounds 1 , 2 , and 5 were applied as catalysts for the direct oxidation of alcohols and amines into the corresponding amides. Compound 6 is an excellent catalyst in the oxidation reactions of benzene and alcohols.     

Oxidative amidation of aromatic aldehydes with amine hydrochloride salts catalyzed by silica‐coated magnetic carbon nanotubes (MagCNTs@SiO2)‐immobilized imine–Cu(I)

Mesoporous silica‐coated magnetic carbon nanotubes were prepared; their surface functionalization, followed by reaction with CuI, were carried out to develop a Cu‐grafted functionalized mesoporous material. This system is able to catalyze oxidative amidation of aromatic aldehydes with amine hydrochloride salts, generating amide derivatives in moderate to good yields. Magnetic properties of this catalyst led to easy separation as well as providing significant recyclability. Copyright © 2013 John Wiley & Sons, Ltd.     

铑（III）催化的醛的氧化胺化：一种有效的构建N-吡啶酰胺及酰亚胺的合成方法

描述了一种采用三价铑催化的醛的氧化胺化反应,利用Ag₂CO₃作为氧化剂.通过该方法可以以良好的收率合成各种类型的N-吡啶酰胺及酰亚胺.