Reduction of Diaryldiselenides by System of Cp_2TiCl_2/Bu^iMgBr/THF and Its Application in Synthesis of Unsymmetrical Diaryl Selenides

Reduction of diaryldiselenides by the system of Cp2TiCl2/Bu'MgBr/THF gave the nucleophilic arylselenium complex. They reacted with diaryl iodonium salts to afford unsymmetrical diaryl selenides in high yields.

Reaction of Arylselenium Titanocene Complexes with Diaryl Iodonium Salts——a Convenient Synthesis of Unsymmetrical Diarylselenides

The diaryldiselenides reacted with titanocene hydried （Cp2TiH） generted from Cp2TiCl2/i-BuMgBr to give arylselenium complexes of titanocene. They reacted readily with diaryliodoiums salt to give unsymmetical diarylselenides.

Azo Bond Reduction of N,N-diaryl Adipyl Bis-azo Compounds with Hydrazine Hydrate

Reduction of a series of N,N＇-diaryl adipyl bis-azo compounds using hydrazine hydrate as reductant was investigated. The products were characterized by elemental analysis, IR and 1H NMR methods and confirmed to be N,N＇-diaryl adipyl dihydrazine. The results show that hydrazine hydrate can selectively reduce azo bonds with other potential reducible bonds intact in the N,N＇-diaryl adipyl bis-azo compounds. The yields are high up to 92% under mild reaction conditions. According to the previous reports, this reduction process was attributed to an indirect reduction mechanism through an intermediate diimide.

An Efficient Synthesis of Diaryl Ethers by Coupling Aryl Halides with Substituted Phenoxytrimethylsilane in the Presence of TBAF

A general synthesis of diaryl ethers via coupling of aryl halides with substituted phenoxytrimethylsilane in the presence of TBAF is described. The protocol is simple and mild, and gives good to excellent yields.

A Rapid and Efficient Synthesis of Diaryl Thioureas via Solvent-Free Reaction Using Microwave

A rapid and efficient method for the preparation of diaryl thiourea compounds was reported for the first time. Twelve diaryl thiourea compounds that possessing biological activity have been synthesized in excellent yields (91-97%). The reaction proved to be extremely simple and highly efficient (in 1.5-4.5 min).

Synthesis and Cytotoxicity of Novel Diaryl Ureas Containing 2-Amino-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidinyl Group

A series of 2-amino-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidinyl substituted diaryl urea derivatives was designed and synthesized. Their in vitro cytotoxicities against two cancer cell lines（Bel-7402 and A549） were evaluated by standard MTT assay. Six of tested compounds 6, 8, 10, 17, 21 and 22 exhibited more potent cytotoxicity superior to sorafenib. The structure activity relationship（SAR） study indicates that 2-amino-5,6,7,8-tetrahydropyrido- [4,3-d]pyrimidinyl group was an option for cytotoxic potency.

LOW-VALENT TITANIUM INDUCED REDUCTIVE CROSS-COUPLING REACTION OF ESTERS WITH DIARYL KETONES

The intermotecular coupling reaction of esters with diarvl ketones induced by titanium tetrachtoride and zinc powder was studied.

SYNTHESIS OF DIARYL ETHERS THROUGH PHASE TRANSFER CATALYSIS WITH POTASSIUN FLUORIDE COATED ALUMINA AS A STRONG BASE

Seven diaryl ethers were synthesized with potassium fluoride coated alumina as a strong base and the addition of catalytic amount of PTC. The yield of diaryl ethers with addition of PTC was much higher than that without PTC.A discussion of the catalysis mechanism was given in this paper.

A Facile Synthesis of 3,5-Diaryl 1,2,4-Selenadiazoles from Aryl Selenoamides

A facile synthesis of 3,5-diaryl 1,2,4-selenadiazoles was provided by treatment of aryl selenoamides with p-methylphenyl sulfonyl chloride in chloroform.

A Simple and Rapid Method for Synthesis of N,2-Diaryl Diazcnecarboxamides

Using Fe2(SO4)3/H2SO4 as oxidant, nine N,2-diaryl diazcnecarboxamides weresynthesized from diaryl substituted semicarbazides in excellent yield under mild conditions for thefirst time. This method is simple, convenient and rapid.

Synthesis, Crystal Structure and Biological Activity of a New 4,5-Diaryl-1H-imidazole Derivative

A new 4,5-diaryl-lH-imidazole was synthesized and characterized by 1H NMR, ESI-MS, elemental analysis and FT-IR. The crystal structure of the title compound （C19H16C12N202, Mr = 375.24） has been determined by single-crystal X-ray diffraction. Crystal parameters： mono- clinic system, space group P2/n, a = 14.349（3）, b = 8.7918（18）, c = 15.352（3） A, β = 108.56（3）°, V = 1836.1（6） A3, Z = 4, F（000） = 776, Dc = 1.357 g/cm3, p = 0.368 mm-1, the final R = 0.0502 and wR = 0.1066 for 2324 observed reflections with 1 〉 2 σ（/）. A total of 16117 reflections were collected, of which 3615 were independent （Rint = 0.0595）. The preliminary bioassay suggested that the title compound exhibits distinct effective inhibition on the proliferation of cancer cell lines.

LOW-VALENT TITANIUM INDUCED REDUCTIVE CROSS-COUPLING REACTION OF ACYL CHLORIDES WITH DIARYL KETONES

Treatment of acyl chlorides and diaryl ketones with an activated Ti(o)reagent,prepared by reduction of TiCl_4 with Zn powder,effects an intermolecular reductive cross-coupling reaction leading to ketones.

Rhodium-Catalyzed Asymmetric Transfer Hydrogenation of Heterocyclic Diaryl Ketones:Facile Access to Key Intermediate of Baloxavir

Transition metal-catalyzed asymmetric transfer hydrogenation has been proven to be a powerful approach for the synthesis of chiral alcohols.Herein,a highly efficient and enantioselective transfer hydrogenation of dibenzoheptaheterocyclic ketones catalyzed by an arene-tethered TsDPEN-based Rh(ll)catalyst has been successfully developed,and a variety of dibenzoheptaheterocyclic ketones were reduced by a 1/1 mixture of formic acid and DBU(1,8-diazabicyclo[5.4.0]undec-7-ene)with high yields and enantioselectivities.With this method,the asymmetric reduction of 7,8-difluorodibenzo[b,e]thiepin-11(6H)-one has been realized,providing the key intermediate of baloxavir marboxil with>99% yield and>99% ee at a substrate/catalyst molar ratio of 1000.

Iron-Catalyzed Reductive C(aryl)—Si Cross-Coupling of Diaryl Ethers with Chlorosilanes

The reductive cross-coupling between C(aryl)—O and Si—Cl bonds is of much importance as a valuable strategy for the construction of C(aryl)—Si bonds but has remained a great challenge.Herein,we report a reductive cross-coupling of diaryl ethers and chlorosilanes via strong electrophilic C(aryl)—O and Si—Cl bonds cleavage by iron catalysis,which constitutes an efficient protocol for the synthesis of a range of functionalized arylsilanes.The combination of low cost FeCl2 as the precatalyst and iPrMgCl as the reductant shows high activity in the successive cleavage of unactivated C(aryl)—O bonds of diaryl ethers and strong electrophilic Si—Cl bonds of chlorosilanes,allowing their cross-coupling in a reductive fashion.The low-valent iron species generated in situ by reduction of FeCl2 with iPrMgCl was proposed,which prefers to initially cleavage the C(aryl)—O bond of diaryl ethers with the chelation help of an o-amide auxiliary.

Photomediated core modification of diaryl dihydrophenzines through three-component alkylarylation of alkenes toward organocatalyzed ATRP

The design and synthesis of a novel organic photocatalyst(OPC)have attracted broad interest from both the organic chemistry and polymer community.Herein,we presented a visible-light-induced alkylarylation of alkenes strategy for core modification of 5,10-diaryl-5,10-dihydrophenazines(DADHPs)under metal-and additive-free conditions,with the aim to develop powerful photocatalyst for organocatalyzed atom transfer radical polymerization(O-ATRP).Good tolerance for a wide variety of functional groups and affording the corresponding tetrasubstituted products in moderate to good yields were achieved in the batch and flow reactor.The experimental and computational mechanistic study confirmed that DADHPs’radical cations andπ-πstacking interactions played important roles in the alkylarylation of alkenes.A series of the tetrasubstituted DADHPs were directly synthesized from the corresponding noncore-modified phenazines,which were demonstrated to be effective organic photoredox catalysts for O-ATRP.Light responsive nature,controlled polymerization manner,and welldefined poly(methyl methacrylate)were achieved via tetrasubstituted DADHPs mediated O-ATRP.

Modular Synthesis of Diarylalkanes by Nickel-Catalyzed 1,1-Diarylation of Unactivated Terminal Alkenes

A nickel-catalyzed 1,1-diarylation of electronically unbiased alkenes has been developed,providing straightforward access to diarylalkanes from readily available materials.Importantly,both the efficiency and the regioselectivity of this transformation are ensured by reaction conditions,rather than the coordinating group of substrates.We also demonstrate that under balloon pressure,ethylene and propylene can also be utilized as substrates.Preliminary mechanistic experiments suggest that this transformation involves a Ni(0)/Ni(Ⅱ)catalytic cycle rather than a Ni(Ⅰ)/Ni(Ⅲ)cycle.

三氟甲基取代1,1-二芳基烷烃衍生物的合成:光诱导CF_(3)Br参与的碳碳双键三氟甲基/芳基化反应

利用光催化与过渡金属催化相结合的协同催化策略,实现了价廉易得的三氟溴甲烷和芳香胺参与的碳碳双键三氟甲基/芳基化反应,合成了一系列具有潜在生物活性的三氟甲基取代的1,1-二芳基烷烃衍生物.探索了以芳香胺为芳基化试剂制备三氟甲基取代1,1-二芳基烷烃衍生物的可能性,丰富了芳基化试剂的种类,明确了芳基化过程进行的条件,并探讨了反应机理.该方法具有反应条件温和、操作简单和底物价廉易得等优点,为含三氟甲基1,1-二芳基烷烃衍生物的合成提供了一种简捷有效的途径.

Design,synthesis and antiproliferative activities of diaryl urea derivatives bearing N-acylhydrazone moiety

A new series of diaryl urea derivatives bearing N-acylhydrazone moiety were designed and synthesized. All the target compounds were evaluated for their antiproliferative activities against human leukemia cell line （HL-60）, human lung adenocarcinoma epithelial cell line （A549） and human breast cancer cell line （MDA-MB-231） in vitro by standard MTT assay. The pharmacological results indicated that some compounds exhibited promising antitumor activities. Compound 1j showed the most potent antiproliferative activity against the tested three cell lines with IC50 values of 0.13 μmol/L, 0.7 μmol/L and 0.5μmol/L, respectively.

Synthesis and in vitro antitumor activity of novel diaryl urea derivatives

A series of novel diaryl ureas containing 4-[（2-amino-6-trifluromethyl）pyrimidine-4-yl]piperazine-l-yl group were synthesized and evaluated for their cytotoxic activities in a panel of human cancer cell lines. Compared with the reference drug Sorafenib,some compounds showed more potent and a broader spectrum of anti-cancer activities.Among them,compound 2p demonstrated significant inhibitory activities against MDA-MB-231,HT-29 and MCF-7 cell lines with IC_（50） values of 0.016,0.63,0.001μmol/L, respectively.