Highly phenylated poly(aryl ether phthalazine)s

Two series of novel amorphous poly(aryl ether phthalazine)s have been prepared via an intramolecular ring closure reaction of poly(aryl ether ketone)s (PAEKs) with hydrazine monohydrate. Fluorinated PAEKs, which display solubility in solvents incorporating a ketone functionality such as acetone or ethyl acetate, were converted to poly(aryl ether phthalazine)s to observe if these polymers would display similar solubility characteristics. The poly(aryl ether phthalazine)s have glass transition temperatures in the range of 278–320°C and show 5% weight loss points greater than 500°C in air and nitrogen atmospheres. The fluorinated poly(aryl ether phthalazine)s were not soluble in ketonic solvents. A series of poly(aryl ether phthalazine)s incorporating pendant 2-naphthalenyl moieties has been prepared in an attempt to produce amorphous, thermally stable polymers with high glass transition temperatures. The polymers have glass transition temperatures in the range of 287–334°C and show 5% weight loss points greater than 500°C in air and nitrogen atmospheres. Poly(aryl ether phthalazine)s undergo an exothermic reaction above the glass transition temperature. The major product of this reaction is a rearrangement of the phthalazine moieties to quiazoline moieties, however some crosslinking of the polymers occurs. Cured samples of the poly(aryl ether phthalazine)s show a small increase in the polymer T_g and are insoluble in all solvents tested. © 1996 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 34:1897–1905, 1996     

Photoinitiated cationic oligomerization of aryl 1-propenyl ethers

A series of aryl 1-propenyl ethers (ArPE) were prepared by the isomerization of the corresponding allyl aryl ethers (AArE) and used for photoinduced cationic polymerization studies. Attempted polymerization reactions using diaryliodonium salts as photoinitiators generally resulted in low yields of oligomers. Further studies revealed that these compounds have much lower reactivity in cationic vinyl polymerization as compared to their alkyl analogues. Moreover, side reactions resulting from chain transfer due to Friedel–Crafts alkylations take place and compete with vinyl polymerization. These side reactions are responsible for the low molecular weights observed in the cationic photopolymerization of aryl 1-propenyl ether monomers. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 3017–3025, 1999     

Galvinoxyl相转移催化合成芳基双偶氮酮类化合物

以二芳基卡巴肼为原料,以Galvinoxyl(自由基)为相转移催化剂,高产率地制得了芳基双偶氮酮类化合物。讨论了反应的可能机理。     

Palladium-catalyzed phosphination of functionalized aryl triflates

Catalytic user-friendly approach to the syntheses of various functionalized aromatic phosphines from their corresponding substituted aryl triflates and triarylphosphines was accomplished. This method is carried out in neutral media and compatible with many functional groups including aldehyde, keto, ester, nitrile, ether and pyridyl groups.     

Highly efficient and functional-group-tolerant catalysts for the palladium-catalyzed coupling of aryl chlorides with thiols

The cross-coupling reaction of aryl chlorides with aliphatic and aromatic thiols catalyzed by palladium complexes of the strongly binding bisphosphine CyPF-tBu ligand (1) is reported. Most of the reactions catalyzed by complexes of ligand 1 occur with turnover numbers that exceed those of previous catalysts by two orders of magnitude. The reactions occur with excellent yields, broad scope and high tolerance of functional groups. Coupling of aryl halides with thiols in the presence of low loadings of catalysts derived from other Josiphos type ligands, as well as ligands of other structural types, are also described.     

Progress in the palladium-catalyzed cyanation of aryl chlorides

The development of new palladium catalysts for the cyanation of various aryl and heteroaryl chlorides is described. The combination of amine co-catalysts with chelating phosphine ligands, for example, 1,4-bis(diphenylphosphino)butane (dppb) or 1,5-bis(diphenylphosphino)pentane (dpppe), allows an efficient cyanation of chloroarenes with simple potassium cyanide. General palladium-catalyzed cyanation of nonactivated and deactivated chloroarenes is possible for the first time. Studies of the oxidative addition of aryl halides to palladium triphenylphosphine complexes in the presence and absence of amines suggest that the co-catalyst is capable of preventing catalyst deactivation caused by the presence of excess cyanide ions in solution.     

Copper catalyzed aryl amidation between Nα-Fmoc-protected amino-acid azides and aryl boronic acids

Abstract

A simple and efficient method for the synthesis of aryl amides via oxidative copper-catalyzed coupling of commercially available aryl boronic acids and bench stable N^α-protected amino-acid azides is reported. The potential utility of this protocol is demonstrated through a survey of diversely substituted aryl boronic acids and several side-chain functionalized amino-acid azides, leading to the preparation of the desired amidated products in good to excellent yields. This amide synthesis is suitable for the preparation of amides (such as peptide aryl amides and sterically hindered amino acids) that are not or hardly accessible via classical approaches.     

Poly(aryl ether amide)s

A general method for the preparation of poly(aryl ether amide)s has been developed where the generation of an aryl ether linkage is the polymer-forming reaction. The amide linkage was found to be sufficiently electron-withdrawing to activate halo-substituents towards nucleophilic aromatic substitution analogous to conventional activating groups (i.e., sulfone, ketone, etc.). Model reactions demonstrated that the amide-activated displacement occurred with high selectivity in near quantitative yield and was judged suitable as a polymer-forming reaction. Appropriately fluoro-substituted amides were prepared and subjected to displacement polymerization with bisphenoxides in a N-methyl-2-pyrrolidone (NMP)/N-cyclohexyl-2-pyrrolidone (CHP) solvent mixture. High molecular weight polymers with glass transition temperatures in the 200–225°C range were obtained. © 1993 John Wiley & Sons, Inc.     

Mild and efficient Pd(PtBu3)2‐catalyzed aminocarbonylation of aryl halides to aryl amides with high selectivity

This work describes a mild and efficient approach for the synthesis of aryl amides via catalytic aminocarbonylation of aryl halides with alicyclic amines using a Pd(P^t Bu₃)₂/NH₄Cl catalyst system. Under mild reaction temperature of 60°C and balloon pressure of CO, 5 mol% Pd(P^t Bu₃)₂ with a cheap NH₄Cl promoter is sufficient for high yields of aryl amides. The influence of reaction parameters such as reaction temperature, ligand type and promoter on catalytic activity was investigated. This work also discusses the catalytic intermediates in detail, and provides a plausible mechanism based on an acid chloride intermediate.     

Facile one‐pot synthesis and thermal cyclopolymerization of aryl bistrifluorovinyl ether monomers bearing reactive pendant groups

A diverse pool of aryl bistrifluorovinyl ether (BTFVE) compounds with reactive pendant groups were prepared in a facile, high yielding three step “one‐pot” synthesis from commercial 4‐bromo(trifluorovinyloxy)benzene. Monomers were confirmed from ATR–FTIR, ¹H, ¹³C, and ¹⁹F NMR, and HRMS analysis. Aryl BTFVE compounds were thermally polymerized to afford perfluorocyclobutyl (PFCB) aryl ether polymers with high number–average molecular weight (M_n) for homopolymers (17,050–27,090) and copolymers with 4,4′‐bis(trifluorovinyloxy)biphenyl monomers (27,860–56,500). The PFCB aryl ether homo‐ and copolymers collectively possess high thermal stability (>299 °C in N₂) and are readily solution processable producing optically transparent films. The thermal polymerization was achieved and reactive moieties remained intact, aside from those functionalized with acrylates. In the case with acrylate functionalized polymers, orthogonal polymerization was achieved by first photopolymerizing the acrylates followed by thermal curing of the aryl trifluorovinyl ether endgroups. Preliminary results in this study produced the successful preparation of photodefinable PFCB aryl ether material. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1887–1893, 2010     

A New Class of Amide Ligands Enable Cu‐Catalyzed Coupling of Sodium Methanesulfinate with (Hetero)aryl Chlorides

((2S ,4R )‐4‐Hydroxy‐N ‐(2‐methylnaphthalen‐1‐yl)pyrrolidine‐2‐carboxamide (HMNPC), an amide derived from 4‐hydroxy‐L ‐proline and 2‐methyl naphthalen‐1‐amine, is a powerful ligand for Cu‐catalyzed coupling of (hetero)aryl halides with sulfinic acid salts, allowing for first time the metal‐catalyzed coupling of (hetero)aryl chlorides and NaSO₂Me. A considerable number of (hetero)aryl chlorides worked well, providing the pharmaceutically important (hetero)aryl methylsulfones in good to excellent yields.     

Copper(I)-catalyzed arylselenylation of aryl bromides and iodides

A new protocol to prepare unsymmetrical diarylselenides using the reaction of aryl bromides and iodides with easily available Bu₃SnSeAr catalyzed by Cu(I) complexes under rather mild conditions and with a very high yield is described.     

Triallyl(aryl)silanes serve as a convenient agent for silicon-based cross-coupling reaction of aryl halides

Triallyl(aryl)silanes, stable and easily accessible arylsilanes, were found to react with aryl bromides in the presence of a palladium catalyst (PdCl₂-PCy₃) and tetrabutylammonium fluoride (TBAF) in good yields. The scope of the reaction is broad, and a wide variety of functional groups are tolerant. Allyl groups on Si are readily cleaved upon treatment with TBAF to form fluorosilanes, silanepolyols, siloxanes and/or their mixed forms, which might be responsible for high efficiency of the reaction.     

Discovery and synthesis of novel phosphine-based ligands for aryl aminations

Three families of ligands were prepared for use in Pd-catalyzed aryl aminations and possibly other Pd-catalyzed reactions. The first series is derived from diarylsulfones, the second from trityl imidazole, and the third from 2-bromobenzophenone. While these ligands were not very general in terms of substrate scope, they do work fairly well under certain specific conditions. Additionally, the preparation of these ligands is amenable to bulk synthesis.     

Cobalt-catalyzed electrochemical vinylation of aryl halides using vinylic acetates

The electroreduction of aryl halides (bromides or chlorides) allows the coupling reaction with vinylic acetates, in the presence of 2,2-bipyridine and catalytic amounts of cobalt bromide, leading to styrene derivatives in good yields.     

氟取代聚芳醚酮低温合成及其结构研究

通过傅克酰基化反应合成4,4'-二(4-氟苯甲酰基)二苯醚、4,4'-二(五氟苯甲酰基)二苯醚、4,4'-二(4-氟苯甲酰基)二苯硫醚以及4,4'-二(五氟苯甲酰基)二苯醚4种长链双卤单体,并进一步制备了含二氮杂萘酮聚芳醚酮聚合物.通过多氟取代双卤单体在含二氮杂萘酮聚芳醚酮聚合物主链中引入氟原子.多氟取代双卤单体具有多...     

Synthesis of indol-3-yl aryl ketones through visible-light-mediated carbonylation

A visible-light-catalyzed synthesis of indol-3-yl aryl ketones from aryldiazonium salts, CO and indoles at room temperature was developed. This process provides a useful method for the preparation of diverse indol-3-yl aryl ketones from readily accessible reactants under base-free, acid-free and transition-metalfree conditions.     

含酚酞结构的聚芳醚酮环状齐聚物的激光质谱表征

在“拟高稀”条件下，以酚酞与甲基酚酞为双羟基型单体，与活性双氟基芳香化合物合成了聚芳醚酮环状齐聚物。通过基质辅助激光解吸电离飞行时间质谱对其环状结构进行了表征。     

水相中钯催化碘代芳烃Ullmann偶联反应研究

研究了吸电子基团的贫电碘代芳烃的Ullmann偶联反应,该反应使用Pd(OAc)2为催化剂,K2CO3为添加剂,以丙酮-水混合液为溶剂,不需要添加额外的还原剂,收率为55-87%。在通过了一系列的试验后,可以认为该反应中的溶剂及碱没有起还原作用,而是碘代芳烃自身作为还原剂,完成整个催化反应的,并首次提出了一种不需要外加还原剂的Pd(II)/Pd(IV)/Pd(II)的催化循环机理。     

Synthesis and Characterization of a Novel Poly(aryl ether) Containing 4-Chloro-2,5-diphenyloxazole

4-Chloro-2,5-bis(4-fluorophenyl)oxazole monomer has successfully been synthesized using cyclization reaction of 4-fluorobenzoyl cyanide with 4-fluorobenzaldehyde. This monomer was converted to poly(aryl ether)s by nucleophilic substitution of the fluorine atoms on the benzene rings of oxazole monomer with bisphenol A. The influence of the reaction time on the molecular weight had been investigated. The polymers were identified by FT-IR,¹H-NMR and TGA. The products exhibited weight-average molar masses up to 2.81 x 10⁴g mol⁻¹ in GPC. These poly(aryl ether)s showed very high thermal stability up to 363 °C for 5 % weight loss in TGA under N₂.