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Research has been conducted on the FeCl (sub)3 -PPh (sub)3 complex. The study of this complex has indicated that it catalyzes electrophilic diamination reaction of the electron-deficient alkenes.

A novel asymmetric carbon-carbon bond formation process based on the application of the Davis-type p-toluenesulfinimines to the tandem vicinal difunctionalization technique is described. The synthetic route involves the use of various Lewis acids to activate p-toluenesulfinimine electrophiles. Experimental results show that the beta-branched (alpha-carbalkoxyvinyl)-cuprates react very well with p-toluenesulfinimines at low temperature when diethylaluminum chloride is added to the reaction system.

N,N-Dichloro-o-nitrobenzenesulfonamide (2-NsNCL2) is an effective electrophilic nitrogen source for the direct diamination of alpha, beta-unsaturated ketones without using any metal catalysts. A simple direct diamination can be carried out by mixing reactants, in a one-pot operation at room temperature.

Research has been conducted on electrophilic diamination reactions. The study of the direct electrophilic diamination reaction of alpha,beta-unsaturated ketones and esters carried out without the use of metal catalysts is presented.

The classical geometry of the 6-endotransition state for nucleophilic additions into oxocarbenium ions can be perturbed by incorporating the reactive groups into medium-sized rings, leading to the formation of 2,6-trans-dialkyl tetrahydropyrans. The bicyclic products exhibit inside–outside stereoisomerism, as seen in numerous macrolide natural products. [ABSTRACT FROM AUTHOR]

N,N-Dichloro-o-nitrobenzenesulfonamide (2-NsNCl[sub 2]) was found to be an effective electrophilic nitrogen source for the direct diamination of α,β-unsaturated ketones without the use of any metal catalysts. The reaction is very convenient to carry out without the protection of inert gases. Molecular sieves (4 Å) and temperature were found to play key roles in controlling the formations of 3-trichloromethyl and dichloromethyl imidazoline products (16 examples). The 2-Ns-protection group of the resulting diamine products can be easily cleaved under mild Fukuyama's conditions. A new mechanism hypothesis of [2+3] cyclization and N-chlorination has been proposed to explain the product structures, particularly their regio- and stereochemistry. [ABSTRACT FROM AUTHOR]

Describes a study on the development of a novel tandem asymmetric carbon-carbon formation process promoted by a Lewis acid. Stereospecific synthesis of the unusual Baylis-Hillman adducts, beta-branched alpha-(aminoalkyl)-acrylates; Anionic additions of vinylcuprates to p-toluenesulfinimines.

A practical one-pot and regiospecific three-component process for the synthesis of 2,3-disubstituted indoles from 2-bromoanilides was developed via consecutive palladium-catalyzed Sonogashira coupling, amidopalladation, and reductive elimination. [ABSTRACT FROM AUTHOR]

Functional nanogels are attractive additives for use in polymer composites. In this study, nanogels with internal allyl sulfide moieties throughout their network structure were prepared via a thiol-Michael addition reaction. The excess thiol-functionalized nanogels were less than 60 nm as discrete particles but act as room-temperature liquids in the bulk state. The reactive nanogels can be dispersed in and swollen by a thiol-ene matrix resin, which upon photopolymerization yields dramatically decreased levels of polymerization shrinkage stress. Furthermore, the postcured nanogel-modified polymers effectively relaxed applied stresses as well as enhanced toughness during exposure to a UV light source that activated the addition-fragmentation as a means for dynamic bond exchange. These nanogels provide a generic approach to introduce adaptable network performance that significantly improves a number of key properties of glassy cross-linked polymer.

Due to the fragility and the poor optoelectronic performances of Si, it is challenging and exciting to fabricate the Si-based flexible light-emitting diode (LED) array devices. Here, a flexible LED array device made of Si microwires-ZnO nanofilm, with the advantages of flexibility, stability, lightweight, and energy savings, is fabricated and can be used as a strain sensor to demonstrate the two-dimensional pressure distribution. Based on piezo-phototronic effect, the intensity of the flexible LED array can be increased more than 3 times (under 60 MPa compressive strains). Additionally, the device is stable and energy saving. The flexible device can still work well after 1000 bending cycles or 6 months placed in the atmosphere, and the power supplied to the flexible LED array is only 8% of the power of the surface-contact LED. The promising Si-based flexible device has wide range application and may revolutionize the technologies of flexible screens, touchpad technology, and smart skin.

A highly concise and convergent synthesis of HCV polymerase inhibitor Deleobuvir (BI 207127, 1) was achieved, featuring efficient Pd-catalyzed one-pot borylation-Suzuki coupling where TFP was identified as the unique ligand effective for these transformations.

In the presence of 20 mol % of tributylphosphine, tert-butyl carbonate substrate 3a undergoes smoothly an intramolecular formal [3 + 2] cycloaddition reaction at room temperature to give benzobicyclo[4.3.0] compounds in 99% yield with a 19/81 ratio of 2a and 2a'. The mechanism of the isomerization of the product 2a into 2a' has been investigated in detail. On the basis of this mechanism, two strategies, using 20 mol % of triphenylphosphine or 10 mol % of tributylphosphine in the presence of 20 mol % of Ti(O(i)Pr)(4), have been established for the selective construction of benzobicyclo[4.3.0] compounds. Under neutral conditions, the reactions of compounds 3a-g afford benzobicyclo[4.3.0] compounds 2a-g with high selectivities in good to excellent yields. In addition, alpha-methyl alpha,beta-unsaturated ester 3h also works well to give the corresponding product 2h with one quaternary carbon center in 99% yield under neutral and room temperature conditions.

[Structure: see text] A practical one-pot, regiospecific three-component process for the synthesis of 2,3-disubstituted indoles was developed via consecutive Pd-catalyzed Sonogashira coupling, amidopalladation, and reductive elimination.

Low-temperature crystal structures of three pyrrolediones (3-5) and a furandione (9) were obtained and compared to structurally related compounds that cannot undergo decarbonylation. Systematic trends in bond lengths and angles are consistent with distortions along the reaction coordinate, in accord with the structure correlation principle of Dunitz. Since the pyrroledione and furandione rings in 3-5 and 9 are planar, these ground-state geometries prefigure the calculated planar, pseudopericyclic transition states.

[reaction: see text] A new three-component halo aldol reaction has been discovered for the tandem formations of I-C/C-C bonds by activating the alpha',beta-positions of alpha,beta-acetylenic ketones. The key intermediates, 1-iodo-3-siloxy-1,3-butadienes, were generated from allenolates and directly monitored by (1)H NMR spectroscopic analysis. Excellent geometric selectivity (>95%) and good yields (65-82%) have been achieved for 10 examples.

The FeCl(3)-PPh(3) complex was found to effectively catalyze the electrophilic diamination reaction of electron-deficient alkenes. Improvements on yields and stereoselectivity have been achieved for both alpha,beta-unsaturated carboxylic esters and ketones. Under the new catalytic system, alpha,beta-unsaturated carboxylic esters were found to be superior to their ketone counterparts, which is opposite to the previous (C(3)F(7)CO(2))(2)Rh](2)-catalyzed diamination. The reaction employs readily available N,N-dichloro-p-toluenesulfonamide (TsNCl(2)) and acetonitrile as the nitrogen sources and is very easy to perform at room temperature without the special protection of inert gases. The resulting diamino products belong to imidazolidine analogue and can further strengthen the importance of the new reaction. Modest to good yields (52-84%) and high regio- and stereoselectivity have been achieved for 10 examples.