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A novel and green method for the synthesis of 3-thiocyanatobenzothiophenes via electrochemical-oxidation promoted difunctionalization of active alkyne has been developed. In this protocol, inexpensive and easily available potassium thiocyanate was chosen as the thiocyanation reagent, 2-alkynylthioanisoles as the substrates, a variety of 3-thiocyanatobenzothiophenes were obtained in moderate to good yields under oxidant- and catalyst-free conditions. Moreover, the continuous flow system has good applicability for this transformation, the use of continuous flow system has overcome the disadvantage of low efficiency in traditional electrochemical amplification, and realized the stable and excellent yields of target products in the scale-up reactions.

By using water as a solvent, an eco-friendly and practical protocol for the synthesis of furans and benzofurans through a Bronsted acid ionic liquid-catalyzed ring opening of 3,3-disubstituted oxet...

Nanoemulsion (NE) is a dosage form widely used in pharmaceutical, food, agrochemical, cosmetics, and personal care industries. NE systems are usually formulated through trial and error via numerous semi-empirical experiments. Moreover, the complex interaction mechanisms between the formulation surfactant and cosurfactant are difficult to understand. Dissipative particle dynamics (DPD) may be helpful in solving these formulation problems. Silibinin is a flavonolignan isolated from milk thistle, which has demonstrated antioxidant and antimicrobial effects. For this project, silibinin-loaded nanoemulsion (SBNE) was formulated by DPD, including surfactant and cosurfactant screening, pseudo-ternary phase construction, and SBNE characterization, all of which were verified by experimentation. Most importantly, this work shows that DPD can be adopted to explore the synergetic mechanisms between the surfactant and cosurfactant, including emulsification efficiency, distance, angle, arrangement, and order parameter. Additional verification experiments on the antioxidant and antimicrobial applications of simulation-designed SBNE were also carried out and confirmed DPD-predicted results. As such, predicting NE formulation by DPD has been proven to be feasible. For SBNE, the addition of PEG400 cosurfactant stretches the Cremophor RH40 surfactant molecules and assists in a more orderly arrangement. An enhanced interfacial thickness in SBNE could be attributed to the stretched hydrophilic head group and the decreased angle between the molecular axis and interface normal. These DPD and experimentally-verified results indicated that a proper cosurfactant will enhance the interfacial thickness, decrease the consumption of surfactant, and benefit NE formation. This new computationally applied knowledge should facilitate optimizing, designing, and understanding NE formulation more rationally and scientifically.

An (S,S)-QuinoxP*-supported Cu(i) catalyst has been disclosed for highly enantioselective intramolecular addition of aryl pinacolboronic esters to unactivated ketones under mild reaction conditions. This protocol showcases a broad substrate tolerance and allows access to various chiral 2,3-dihydrobenzofuran-3-ol derivatives in generally good yields with excellent enantioselectivities.

Herein is reported the formal (3 + 3) annulations of δ-acetoxy allenoates with 1C,3O-bisnucleophiles by using 6’-deoxy-6’-perfluorobenzamido-quinine (5g) as the catalyst, providing rapid access to 4H-pyrans with excellent enantioselectivity. The reaction features wide substrate scope and mild reaction conditions. The utility of this method is demonstrated in highly stereoselective synthesis of the core of calyxin I. Mechanistic experiments suggest the involvement of 3-ammonium-2,4-dienoate intermediate BN. This type of cationic intermediate arises from an addition-elimination process between allenoate substrate and amine catalyst, and is stable enough for isolation and characterization. Mechanistic studies also disclose the crucial role of amide NH of 5g, which is able to not only activate allenoate to facilitate the formation of BN, but enhance the electrophilicity of δC of BN for nucleophilic attack.

Here, the highly enantioselective construction of 3,3-disubstituted tetrahydropyridines via Pd(0)-catalyzed asymmetric vinylborylation of (Z)-1-iodo-dienes and B2pin2 in the presence of a (S)-p-CF3-BnPHOX ligand is reported. This process is supposed to be initiated by oxidative addition of Pd(0) to vinyl iodide, followed by transmetallation with B2pin2, insertion of the pendant alkene and reductive elimination of alkyl–Pd(II)-Bpin.

Here is reported the DMAP-catalyzed addition/(4 + 2) annulation domino reaction of δ-acetoxy allenoate with either salicylaldehyde-derived oxadiene or pyrrolealdehyde-derived oxadiene, which provides a facile method toward polycyclic frameworks. A cationic intermediate, 3-ammonium-2,4-dienoate, is proposed to be involved via an addition-elimination process between an allenoate and a catalyst, which is capable of undergoing addition with either O- or N-nucleophile and subsequent (4 + 2) annulation with oxadiene.

Two classes of phosphine-catalyzed addition/cycloaddition domino reactions of β'-acetoxy allenoate 1 have been developed. The reaction of 1 with 2-acyl-3-methyl-acrylonitrile 2 readily occurs to give 2-oxabicyclo[3.3.1]nonane 3, furnishing the β'-addition/[4 + 4] cycloaddition domino sequence. In this sequence, β'C of allenoate 1 is an electrophilic center, and its β'C and γC serve as a 1,4-dipole. When the other reaction partner is switched to 2-acyl-3-(2-pyrrole)-acrylonitrile 8, a γ-addition/[3 + 2] cycloaddition domino reaction is instead observed, in which allenoate 1 exhibits dual electrophilic reactivity of γC and 1,3-dipole chemical behavior of βC and β'C. Furthermore, both of these two asymmetric variants have also been achieved with up to 93% ee. The domino reactions presented in this report are valuable for highly stereoselective construction of complex structures under mild reaction conditions.

While the phosphine catalysis is a powerful tool for the construction of N-heterocycles, the phosphine-catalyzed annulations toward lactam motif are still extremely scarce. Here, we report the asymmetric (3 + 2) annulations of δ-acetoxy allenoates with β-carbonyl amides by using the (R)-SITCP catalyst. The δC and γC of allenoate respectively engage in annulation with the αC and N of the amide, forging a γ-lactam with good to excellent stereoselectivity.

The formal (3 + 3) annulations of δ-acetoxy allenoates and 1C,3O-bisnucleophiles are reported with the use of 6′-deoxy-6′-perfluorobenzamido-quinine (4g) as a catalyst, which provide rapid access to 4H-pyrans with excellent enantioselectivity. The reaction features a wide reaction scope and mild reaction conditions. The crucial roles of amide NH of 4g as a H-bond donor have also been elucidated, which not only activates allenoate to facilitate formation of cationic intermediate A but also enhances the electrophilicity of its δ-position for nucleophilic 1,6-addition.

DABCO-catalyzed formal (3+3) annulations of β'-acetoxy allenoates with indoline-2-thiones are described, which provide facile access to thiopyrano[2,3-b]indole under mild reaction conditions. The reaction might proceed via the SN2'-SN2'-type process between β'-acetoxy allenoate and indole-2-thiolate with the assistance of the DABCO catalyst and K2CO3 additive, followed by intramolecular Friedel-Crafts reaction at the 3-position of indole and central carbon of allene.

The asymmetric (3 + 3) annulations of β′-acetoxy allenoates with either 3-oxo-nitriles or pyrazolones have been realized by using 6′-deoxy-6′-[(l)-N,N-(2,2′-oxidiethyl)-valine amido]quinine (6h) as the catalyst. The three functions of catalyst 6h, including Lewis base (quinuclidine N), H-bond donor (amide NH), and Bronsted base (morpholine N), cooperatively take crucial roles on the chemo- and enantioselectivity, allowing for the construction of 4H-pyran and 4H-pyrano[2,3-c]pyrazole in high yields and enantioselectivity.

The asymmetric (3 + 3) annulations of β′-acetoxy allenoates with either 3-oxo-nitriles or pyrazolones have been realized by using 6′-deoxy-6′-[(l)-N,N-(2,2′-oxidiethyl)-valine amido]quinine (6h) as the catalyst. The three functions of catalyst 6h, including Lewis base (quinuclidine N), H-bond donor (amide NH), and Bronsted base (morpholine N), cooperatively take crucial roles on the chemo- and enantioselectivity, allowing for the construction of 4H-pyran and 4H-pyrano[2,3-c]pyrazole in high yields and enantioselectivity.

Magnetic Pt3Co nanoparticles with a diameter of 4.5 ± 0.45 nm were synthesized by a co-precipitation technique. The Pt3Co nanoparticles were studied by ultraviolet–visible spectroscopy, x-ray diffraction and transmission electron microscopy, and a superconducting quantum interference device respectively. Studies revealed that the Pt3Co nanoparticles were stable and did not show any oxidation even after annealing at 200°C under ambient conditions, and as-prepared Pt3Co nanoparticles were superparamagnetic above the blocking temperature, while below the blocking temperature the nanoparticles exhibited ferromagnetic behavior. In addition, the coercivity of the Pt3Co nanoparticles increased dramatically to 820 Oe after annealing at 700°C.

Some task-specific ionic liquids N,N,N′,N′-tetramethyl-N,N′-dipropanesulfonic acid ethylene-diammonium hydrogen sulfate, N,N,N′,N′-tetramethyl-N,N′-dipropanesulfonic acid-1,3-propanediammonium hydrogen sulfate, N,N,N′,N′- tetramethyl-N,N′- dipropanesulfonic acid-1,6-hexanediammonium hydrogen sulfate were prepared. These ionic liquids could be used as efficient and recyclable catalysts for the synthesis of α-aminophosphonates at room temperature via an one-pot three-component reaction under organic solvent-free conditions with good yields of 83–96%. The postprocessing was simple, and the catalysts could be reused at least six times without noticeably decreasing the catalytic activity. The novel clean procedure offers the advantages including short reaction time, good yields, operational simplicity, and environmentally benign. © 2010 Wiley Periodicals, Inc. Heteroatom Chem 22:1–5, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/hc.20647

SO3H-functionalized halogen-free ionic liquids were prepared and used as efficient and recyclable catalysts for the synthesis of α-aminophosphonates at room temperature via the one-pot three-component condensation reaction in aqueous media with good yields of 80–96%. The postprocessing was simple, and the catalysts could be reused at least six times without noticeably decreasing the catalytic activity. © 2010 Wiley Periodicals, Inc. Heteroatom Chem 21:546–550, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/hc.20644

Two classes of phosphine-catalyzed addition/cycloaddition domino reactions of β′-acetoxy allenoate 1 have been developed. The reaction of 1 with 2-acyl-3-methyl-acrylonitrile 2 readily occurs to give 2-oxabicyclo[3.3.1]nonane 3, furnishing the β′-addition/[4 + 4] cycloaddition domino sequence. In this sequence, β′C of allenoate 1 is an electrophilic center, and its β′C and γC serve as a 1,4-dipole. When the other reaction partner is switched to 2-acyl-3-(2-pyrrole)-acrylonitrile 8, a γ-addition/[3 + 2] cycloaddition domino reaction is instead observed, in which allenoate 1 exhibits dual electrophilic reactivity of γC and 1,3-dipole chemical behavior of βC and β′C. Furthermore, both of these two asymmetric variants have also been achieved with up to 93% ee. The domino reactions presented in this report are valuable for highly stereoselective construction of complex structures under mild reaction conditions.

Dicationic ionic liquids, e.g. DIL, are prepared and applied as acidic catalysts in a facile three-component, one-pot synthesis of α-aminophosphonates (IV).

SO3H-functionalized halogen-free ionic liquids were prepared and used as efficient and recyclable catalysts for the synthesis of α-aminophosphonates at room temperature via the one-pot three-component condensation reaction in aqueous media with good yields of 80–96%. The postprocessing was simple, and the catalysts could be reused at least six times without noticeably decreasing the catalytic activity. © 2010 Wiley Periodicals, Inc. Heteroatom Chem 21:546–550, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/hc.20644