Tf2O-Mediated Tandem Reaction of Enaminones for the Synthesis of Functionalized Conjugated-Enals/ß-Naphthalaldehydes.

A highly efficient and regioselective method for constructing functionalized conjugated enals via the Tf2O-mediated tandem reaction of enaminones with thiophenols has been described. Chain products with excellent stereoselectivity could be obtained through substrate regulation. Additionally, a feasible method for synthesizing ß-naphthalaldehydes through PhSO2Na/DABCO promoting hydrogen atom transfer process has also been reported here. Mechanism studies have shown that 2-formyl vinyl triflate 8 and sulfonylated enal 9 were the key intermediates in this process.

Synthesis of Indolizines via Tf2O-Mediated Cascade Reaction of Pyridyl-enaminones with Thiophenols/Thioalcohols.

A cost-effective, highly regioselective and metal-free version for the synthesis of indolizine derivatives by means of Tf2O-mediated cascade reaction of pyridyl-enaminones and thiophenols/thioalcohols under mild reaction conditions has been reported. Diverse electron-rich indolizine derivatives could be obtained in up to 94% yield via the selective 1,4-addition of vinyl iminium triflate tandem cyclization/aromatization, which allowed the simultaneous construction of C-N and C-S/and one example of C-Se bonds.

Synthesis of aryloxyacetamides from arylboronic acids and 2-bromoacetonitrile promoted by alkaline solutions of hydrogen peroxide.

A novel and metal catalyst-free synthesis of aryloxyacetamides from the corresponding arylboronic acids and 2-bromoacetonitrile promoted by alkaline solutions of hydrogen peroxide has been developed involving an oxidation-reduction of eco-friendly H2O2 with simultaneous reaction ipso-hydroxylation of arylboronic acid and hydration of the nitrile. This protocol is compatible with sensitive substituents attached to the arylboronic acid and provides desired products in moderate to good yields in pure water.

One-Pot Synthesis of Symmetrical and Asymmetrical 3-Amino Diynes via Cu(I)-Catalyzed Reaction of Enaminones with Terminal Alkynes.

An economical and efficient protocol for the direct construction of amino skipped diynes through the Cu(I)-catalyzed reaction of enaminones and terminal alkynes has been described. Different kinds of symmetrical and asymmetrical 3-amino diynes could be obtained in up to 83% yield through a one-pot reaction under mild conditions.

Synthesis of New 2-Arylbenzo[b]furan Derivatives via Palladium-Catalyzed Suzuki Cross-Coupling Reactions in Aqueous Media.

A series of novel benzofuran derivatives containing biaryl moiety were designed and synthesized by the Suzuki cross-coupling reactions. The reactions, performed in the presence of K2CO3, EtOH/H2O and Pd(II) complex as catalyst, gave the corresponding products in good to excellent yields. The methodology allows the facile production of heterobiaryl compounds, a unique architectural motif that is ubiquitous in medicinal chemistry.

An Efficient Synthesis of Arylated Pyridines from Conjugated Acetylenes and Substituted Benzylamines Catalyzed by Base.

An efficient base-catalyzed synthesis of arylated pyridines has been disclosed. This reaction involving conjugated acetylenes and substituted benzylamines proceeded smoothly, giving rise to tri-aryl substituted pyridines which are biologically relevant compounds in good to excellent yields in N,N-dimethylformamide (DMF) under air at 140 °C with K2CO3 as catalyst.

Multicomponent Reactions with Cyclic Tertiary Amines Enabled by Facile C-N Bond Cleavage.

A novel and catalyst-free multicomponent reaction with cyclic tertiary amines, electron-deficient aryl halides or heteroaromatic halides, and Na2 S enabled by facile C-N bond cleavage of the cyclic tertiary amines was developed. This direct and operationally simple method can be applied with a wide range of functional groups and provides an efficient and rapid approach to potentially drug-like products containing amine, azaarene, thioether, or phenol ether functionalities in good to excellent yields. The utility of this method was demonstrated by the rapid synthesis of the analgesic ruzadolane.

A Well-Defined {[(PhCH2O)2P(CH3)2CHNCH(CH3)2]2PdCl2} Complex Catalyzed Hiyama Coupling of Aryl Bromides with Arylsilanes.

A palladium (II) complex {[(PhCH2O)2P(CH3)2CHNCH(CH3)2]2PdCl2} catalyzed Hiyama cross-coupling reaction between aryl bromides and arylsilanes has been developed. The substituted biaryls were produced in moderate to high yields, regardless of electron-withdrawing or electron-donating.

The Homocoupling Reaction of Aromatic Terminal Alkynes by a Highly Active Palladium(II)/AgNO3 Cocatalyst in Aqueous Media Under Aerobic Conditions.

A new and efficient Pd(II)/AgNO3-cocatalyzed homocoupling of aromatic terminal alkynes is described. Various symmetrical 1,4-disubstituted-1,3-diynes are obtained in good to excellent yields. This protocol employs a loading with relatively low palladium(II) in aqueous media under aerobic conditions.

MIDA as a simple and highly efficient ligand for palladium-catalyzed Hiyama cross-coupling of aryl halides.

N-Methyliminodiacetic acid (MIDA) as a simple, air stable and water-soluble ligand has been used in the palladium-catalyzed Hiyama cross-coupling reaction of trimethoxyphenylsilane with aryl halides. The yield of the corresponding Hiyama coupling products is high up to around 90% in water and isopropanol under an ambient atmosphere in the presence of KOH and NaF.

A simple hydrophilic palladium(II) complex as a highly efficient catalyst for room temperature aerobic Suzuki coupling reactions in aqueous media.

A study on room temperature Suzuki cross-coupling in an aqueous medium was carried out using a simple hydrophilic palladium (II) complex, trans-PdCl2(NH2CH2COOH)2 as catalyst in the presence of K2CO3 in air. This approach with a comparatively inexpensive and hydrophilic catalyst, mild reaction condition and aqueous media exhibits excellent catalytic activity towards the Suzuki coupling of aryl bromides and arylboronic acids, and good yields were obtained in the Suzuki coupling of activated aryl chlorides.

A highly efficient catalyst of a nitrogen-based ligand for the Suzuki coupling reaction at room temperature under air in neat water.

Glycine, as a kind of commercially available and inexpensive ligand, is used to prepare an air-stable and water-soluble catalyst for the Suzuki-Miyaura reaction in our study. In the presence of 0.1% [PdCl2(NH2CH2COOH)2] as the catalyst, extremely excellent catalytic activity towards the Suzuki-Miyaura coupling of aryl halides containing the carboxyl group with various aryl boronic acids is observed at room temperature under air in neat water.

Naphthalene-1,4,5,8-tetra-carboxylic acid 1,8-anhydride-4,4'-bipyridine (1/1).

The title compound, C(14)H(6)O(7)·C(10)H(8)N(2), has been hydro-thermally synthesized. Structural ananlysis indicates that the crystals are produced by cocrystallization of naphthalene-1,4,5,8-tetra-carboxylic acid 1,8-anhydride and 4,4'-bipyridine (bpy) mol-ecules. The crystal packing is stabilized by inter-molecular O-H⋯N and C-H⋯O hydrogen bonds and π-π stacking inter-actions [centroid-centroid distances = 3.5846 (9) Å].

1-(2',4'-Difluoro-biphenyl-4-yl)ethanone.

In the crystal structure of the title compound, C(14)H(10)F(2)O, the dihedral angles between the benzene rings in the two crystallographically independent mol-ecules are 46.9 (2) and 47.6 (2)°. The mol-ecules are linked into dimers by C-H⋯F inter-actions and these dimers are further stacked into columns along the b axis by π-π inter-actions between the benzene rings [centroid-centroid distance = 3.8221 Å; the dihedral angle between the planes of these rings is 4.87 (2)°]. In addition, C-F⋯π interactions also contribute to the crystal packing (C⋯centroid distance = 3.5919 Å).

Diaqua-bis(8-chloro-1,3-dimethyl-2,6-dioxo-1,2,3,6-tetra-hydro-7H-purinato-κN)copper(II) dihydrate.

The title mononuclear copper(II) complex, [Cu(C(7)H(6)ClN(4)O(2))(2)(H(2)O)(2)]·2H(2)O, based on 8-chloro-theophylline (HCt), has the Cu atom at a center of symmetry in a slightly distorted trans square-planar geometry coordinated by two N atoms of two deprotonated HCt ligands and two O atoms of water mol-ecules. The crystal packing is stabilized by hydrogen bonds involving deprotonated HCt ligands, coordinated water mol-ecules and uncoordinated solvent water mol-ecules.