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We describe a visible light-induced palladium-catalyzed radical germylative arylation of alkenes with easily accessible chlorogermanes. This protocol provides expedient access to germanium-substituted indolin-2-ones in good to excellent yields under mild reaction conditions. The key step for this strategy lies in the reductive activation of germanium–chloride bonds with an excited palladium complex under visible light irradiation. The involvement of germanium radicals was evidenced by electron paramagnetic resonance spectroscopy experiments.

Herein, we report the first rhodium-catalyzed hydrolytic cleavage of the silicon–carbon bond in silacyclobutanes using water as the reactant. A series of silacyclobutanes could be employed in this reaction in the presence of the Rh/BINAP complex, resulting in the corresponding silanols in good yields. Additionally, a chiral 1,1,4,4-tetraaryl-2,3-O-isopropylidene-l-threitol-derived phosphoramidite ligand could be used in this reaction to yield Si-stereogenic silanol with promising enantioselectivity.

We report a rhodium-catalyzed anti-Markovnikov regioselective hydrosilylation of trifluoromethylalkenes with substituted silanes giving various α-trifluoromethyl-β-silanes in good to excellent yields. The hydrogenation products were obtained via the same key intermediate treated with methanol as a protic solvent. Both transformations had a broad functional tolerance and were expected to facilitate the construction of complex α-trifluoromethyl compounds.

In view of the exciting advancement on silicon-carbon bond-forming transformations achieved in the past decade, this review intends to show a unified illustration of the recent findings on enantioselective Si-H bond functionalization aided by asymmetric catalysis. Accordingly, this review describes the enantioselective silicon-carbon bond-forming Si-H bond functionalization, focusing on the reactivity and stereoselectivity in catalytic asymmetric hydrosilylation, carbene Si-H insertion, Si-H silylation, and Si-C bond-forming cross-coupling reactions that were achieved with high enantioselectivity in the presence of transition-metal catalyst systems. This review highlights recent and representative examples of the enantioselective Si-H bond functionalization, discusses the origins of silicon-involving stereoselectivities, and evaluates the substrate scopes and limitations in these catalytic asymmetric Si-H bond functionalization reactions due to the special reactivity of different hydrosilanes.

A novel strategy is demonstrated for Lewis base-activated trifluoromethylsulfinylation of allylic alcohols. Controllable synthesis of structurally varied allylic trifluoromethanesulfones via sigmatropic rearrangements was performed, and trifluoromethanesulfinate esters were achieved. This metal-free, catalytic divergent transformation features good functional group tolerance and late-stage modification of bioactive molecules. Mechanistic studies suggested that Lewis bases interact with N-(trifluoromethylsulfinyl)phthalimide to generate an ion pair adduct followed by O-trifluoromethylsulfinylation with allylic alcohols.

Enantiopure atropisomers have become increasingly important in asymmetric synthesis and catalysis, pharmaceutical science, and material science since the discovery of inherent features of axial chirality originating from rotational restriction. Despite the advances made in this field to date, it remains highly desirable to construct structurally diverse atropisomers with potentially useful functions. We propose superposition to match axial and point chirality as a potentially useful strategy to access structurally complex and diverse building blocks for organic synthesis and pharmaceutical science because merging atropisomeric backbones with one or more extra chiral elements can topologically broaden three-dimensional environments to create complex scaffolds with multiple tunable parameters. Over the past decade, we have successfully implemented a strategic design for the superposition of axial and point chirality to develop a series of enantiopure atropisomers and have utilized the synergistic functions of these molecules to enhance chirality transfer in various catalytic asymmetric transformations.

The synthesis of chiral organosilicon compounds is highly appealing due to their wide and important applications in synthetic chemistry and medicinal science. However, catalytic asymmetric disilylation are surprisingly underrepresented because of the lack of enantioselective methods in the stereoselective control of silyl group transformations. Herein, an asymmetric palladium‐catalyzed disilylation of ether‐tethered aryl iodide contained a styrene moiety through Heck/C−H activation sequence was explored for the first time. Upon high‐throughput screening of TADDOL‐derived phosphoramidites, it was found that L18is a good match in combination with Pd(dtbpf)Cl2in the tandem Heck/C−H activation of aryl iodide with hexamethyldisilane to afford disilylated 2.3‐dihydrobenzofunan derivatives in good yields with moderate enantioselectivity. A TADDOL‐derived phosphoramidite ligandwas found to be a good match in combination with Pd(dtbpf)Cl2in the palladium‐catalyzed tandem Heck/C−H activation of aryl iodide with hexamethyldisilane to afford disilylated 2,3‐dihydrobenzofunan derivatives in good yields with moderated enantioselectivity.

The enantioselective construction of a family of chiral glycine-derived aldimino esters is described. The asymmetric tandem conjugate addition–elimination procedure is characterized by its exceptional mild reaction conditions and features with an exquisite enantioselectivity profile using commercially available silver/DTBM-SegPhos catalyst, allowing for the facile preparation of a variety of substituted and chiral glutamic acid derivatives (up to 99% ee) bearing Schiff base in a straightforward manner.

A Lewis acid-catalyzed intramolecular Hosomi–Sakurai reaction of o-(allylsilyl)benzaldehyde/ketone has been developed. The reaction proceeds through simultaneous C–Si bond cleavage and C–C bond reconstruction. This protocol provides a rapid approach for the synthesis of allyl-substituted benzoxasiloles under mild conditions.

The development of highly effective chiral ligands is a key topic in enhancing the catalytic activity and selectivity in metal-catalyzed asymmetric synthesis. Traditionally, the difficulty of ligand synthesis, insufficient accuracy in controlling the stereoselectivity, and poor universality of the systems often become obstacles in this field. Using the concept of nonequivalent coordination to the metal, our group has designed and synthesized a series of new chiral catalysts to access various carbon/silicon and/or multiple stereogenic centers containing products with excellent chemo-, diastereo-, and enantioselectivity.

The mechanism of Pd-catalyzed desymmetric monoarylation of dihydrosilanes with aryl iodides in the presence of chiral TADDOL-derived phosphoramidite ligand toward deeper understanding of the stereoselectivity has been investigated using hybrid density functional theory (DFT) methodology. The full catalytic cycle for the favorable reaction pathway, which is initiated by the oxidative addition of aryl iodide to monoligated Pd0leading to the silylation product, was calculated. The DFT calculation results indicate that the enantio-discriminating transmetalation between Pd–Ar bond of the Pd(II) aryl iodide complex and Si–H bond of the prochiral dihydrosilane was the enantioselectivity-determining step. On the basis of the structure of the transition state, the attractive aryl–aryl interactions between the aryl group of ligand, aryl iodide, and dihydrosilane were found to play an important role for the chiral transference from the chiral ligand to asymmetric cleavage of the Si–H bond of the prochiral dihydrosilane.

“On water” catalytic aldol reaction catalyzed by polyetheramine (D230) has been developed for easy access to 3-substituted 3-hydroxyindolin-2-ones through the reaction between various substituted isatins and acetophenones/cyclic ketones in high yields under room temperature. Systematic mechanism investigation uncovers the secret for the on water catalytic aldol reaction: comparison of the heterogeneous and homogeneous reaction circumstances with yields of 95 and 20%, respectively, indicates the on-water reaction dominating; interfacial hydrogen bonding between isatin with H2O is tested based on the downfield shift of the C2 and C3’s 13C NMR signals when water was added to the CDCl3solution of isatin; Lewis base polyetheramine D230 catalyzes the aldol reaction via the enamine mechanism verified by in situ NMR and ESI-MS analysis.

An atom‐economical strategy for the synthesis of functionalized alkylidenecyclobutanes (ACBs) via Lewis acid‐catalyzed yne‐carbonyl metathesis of ynamides and cyclobutanones is described. This strategy features mild reaction conditions, ready availability of starting materials, and broad functional group tolerability. Furthermore, the imide group is easily converted to acid, ester, and amide, thus providing an efficient access to various functionalized ACBs. An atom‐economical strategyfor the synthesis of functionalized alkylidenecyclobutanes (ACBs) via Lewis acid‐catalyzed yne‐carbonyl metathesis of ynamides and cyclobutanones is described.

An enantioselective magnesium-catalyzed conjugate addition of trimethylsilyl cyanide to chalcones in the presence of Py-BINMOL with multiple stereogenic centers, through dual activation of substrates, has been successfully developed with moderate to good enantioselectivities and in good yields.

Ad Hoc network, a self-organization network system, can establish a communication to a plurality of mobile users without any infrastructure. All nodes in this type of network system exist via portable sources. The hot spot of Ad Hoc network is to realize further energy consumption reduction. In the work, an improved protocol, by which energy consumption is reduced, is proposed based on AODV protocol; named NL-AODV, it choose the optimal routing by the capacity, the nodes energy and the hop. It is verified that the improved protocol can effectively prolong the original lifetime of the network and obviously improve the routing efficiency by simulations. Consequently, it is more suitable for dynamic topology changes in the network system at present.

The rapid increase of information technology usage demands the high level of security in order to keep the data resources and equipments of the user secure. In this current era of networks, there is an eventual stipulate for development which is consistent, extensible and easily manageable, with low maintenance cost solutions for Intrusion Detection. Network Intrusion Detection based on rules formulation is an efficient approach to classify various types of attack. DoS or Probing attack are relatively more common, and can be detected more accurately if contributing parameters are formulated in terms of rules. Genetic Algorithm is used to devise such rule. It is found that accuracy of rule based learning increases with the number of iteration.

Sevelamer, as a phosphate-binding drug, was used as a novel and highly efficient catalyst in the Knoevenagel reaction in water. The Sevelamer, as catalyst, can be recovered and reused numerous times (up to 15 times) without any activity loss.

An iridium-catalyzed, directing group-enabled site selective intra- and intermolecular silylation of indoles and pyrroles with hydrosilanes has been developed under ligand-free conditions. Fine-tuning of the removable 3-alkyl-2-pyridyl directing group was found to be crucial for achieving high yields for C2-silylated indole and pyrrole products. Moreover, the scalability was demonstrated, and further transformations of the silylation products were achieved.

A very simple, direct, bismuth‐catalyzed conjugate reduction protocol that allows for the catalytic regioselective formation of substituted ketones from enones under mild conditions has been developed. We have shown for the first time that the combined poly(methylhydro)siloxane‐malononitrile system can serve as an efficient reductant/reagent in 1,4‐conjugate reduction of enones. The regioselectivity, efficiencies, and experimental simplicity of the present method complements the more complex methods previously employed in copper or palladium‐catalyzed reduction. This method should prove attractive because of its mild reaction conditions and the interesting chemistry of combining the use of poly(methylhydro)siloxane and malononitrile for selective reduction.

An intelligent self-locking system of clutch which uses MC9S12XS128MAL as the main microcontroller was designed in this research. The system detects whether the door is completely closed or not by the position switch installed in the door rail to achieve control of the clutch pedal. When the door of bus is not completely closed, the driver cannot push down the clutch pedal to drive the bus. Doing that can we achieve automotive driver assistance and further improve driving safety. This paper also discusses the design of the system’s hardware circuitry and procedures.

An unprecedented lateral sequential lithiation/silylation/condensation of tertiary aromatic amides has been developed that provides an efficient method to build up functional olefins in good yields. In addition, we have established an efficient and simple method that involves UV/Vis, fluorescence, and NMR analyses, to detect the interaction between transition‐metal salts and functional olefins containing tertiary amides. This has enabled a highly efficient palladium‐catalyzed Suzuki coupling reaction in the presence of tertiary aromatic amide‐derived olefin ligands to be developed. The best results were obtained by employing 2 mol‐% Pd(OAc)2, 2 equiv. Cs2CO3, a reaction temperature of 80 °C, dioxane as the solvent, and phosphane‐free olefin 2das ligand.

The regioslective reduction of electron‐rich dienes to monoolefins and the reductive cleavage of allyl esters were fulfilled by employing a sodium borohydride‐nickel chloride‐methanol catalytic system with exceedingly simple manipulations and high functional group tolerability. Both of the reductive reactions may involve π‐allylnickel intermediates generated from fresh nickel boride.

The one‐pot, organocatalytic Hayashi sequential reaction (HSR) of β‐nitroacrylate, aldehyde, toluenethiol, and ethyl 2‐(diethoxyphosphoryl)acrylate allowed the synthesis of almost stereoisomerically pure, highly functionalized polysubstituted cyclohexanes with very high diastereo‐ and enantio‐selectivity (up to > 99 % ee). The one‐pot synthesis consists of the tertiary amine modified diarylprolinol silyl ether‐mediated asymmetric Michael reaction, a domino Michael reaction/Horner–Wadsworth–Emmons reaction, and a sulfa‐Michael reaction. In addition, we have also demonstrated an improved protocol for the domino oxa‐Michael/aldol reaction of salicyladehydes with α,β‐unsaturated aldehydes with recyclable tertiary amine‐modified diarylprolinol silyl ether 3das an effective organocatalyst, which results in the formation of chiral chromenes with good enantioselectivities (up to 94 % ee). UV/Vis and CD spectroscopy provide a cross‐validation method to elucidate the slight difference between electron‐withdrawing 3dand diphenylprolinol silyl ether 3a, which can give indirect evidence for the enhancement of enantioselective induction with 3din the above transformations.

2′‐Hydroxy‐1,1′‐binaphthalene‐2‐(arylmethanol) (Ar‐BINMOLs), a family of new 1,1′‐binaphthalene‐2,2′‐diol derivatives, prepared by a [1,2]‐Wittig rearrangement, are introduced as new chiral molecules for the study of the modes of supramolecular aggregation on the basis of ESI‐MS, NMR spectroscopy, differential scanning calorimetry (DSC), and X‐ray diffractometry. Characterization showed that Ar‐BINMOLs exhibit different characteristics to BINOL and act as supramolecules due to hydrogen bonding and aromatic π–π/C–H···π interactions. In particular, CD measurements of chiral and racemic Ar‐BINMOL 2ain solution and the solid state show a strong Cotton effect, which revealed that amplification of chirality was observed because of the formation of a chiral supramolecular oligomer derived from the racemic monomer. To this end, the Ar‐BINMOLs were used as supramolecular auxiliaries to mediate the Michael reaction of anthrone to (E)‐β‐nitrostyrene and could give the Michael adduct with comparable enantioselectivities. In addition, the Ar‐BINMOLs act as ligands to promote asymmetric 1,2‐addition of diethylzinc to aldehydes, which resulted in excellent yields and enantioselectivities (up to >99.9 % ee) in the reactions of diethylzinc with a broad range of aromatic aldehdyes.

A detailed experimental investigation of an aza‐Michael reaction of aniline and chalcone is presented. A series of Cinchonaalkaloid‐derived organocatalysts with different functional groups were prepared and used in the aza‐Michael and retro‐aza‐Michael reaction. There was an interesting finding that a complete reversal of stereoselectivity when a benzoyl group was introduced to the cinchonine and cinchonidine. The chirality amplification vs. time proceeds in the quinine‐derived organocatalyst containing silicon‐based bulky group, QN‐TBS, ‐catalyzed aza‐Michael reaction under solvent‐free conditions. In addition, we have demonstrated for the first time that racemization was occurred in suitable solvents under mild conditions due to retro‐aza‐Michael reaction of the Michael adduct of aniline with chalcone. These indicate the equilibrium of retro‐aza‐Michael reaction and aza‐Michael reaction produce the happening of chirality amplification in aza‐Michael reaction and racemization via retro‐aza‐Michael reaction under different conditions, which would be beneficial to the development of novel chiral catalysts for the aza‐Michael reactions. Chirality, 2011. © 2011 Wiley‐Liss, Inc.

A novel metal‐free intramolecular Brønsted‐acid‐catalyzed domino deprotection–hydrosilylation with hydrosilanes has been developed, and the unexpected Brønsted‐acid‐catalyzed intermolecular hydrolytic oxidation to functional siloxanes was described for the divergent and facile synthesis of functionalized siloxanes containing aldehyde motifs. We propose that these reactions proceed via neighboring acetal‐assisted Si–H bond activation. In addition, a related reaction is expected to open up further opportunities for the development and application of functional organosilicon compounds by organocatalysis.

A facile and practical methodology for the synthesis of synthetically useful diarylmethanol‐based 1,4‐diols and enantiomerically pure BINOL‐derived diols with axial and sp3‐central chirality has been developed through neighboring lithium‐promoted [1,2]‐Wittig rearrangement. The chirality transfer process shows a broad substrate scope in terms of the aromatic ether substituent, which allows access to a broad of range of chiral 1,1′‐binaphthalene‐2‐α‐arylmethanol‐2′‐ols with excellent enantioselectivities (>99 % enantiomeric excess) and yields (84–96 %). This should be considered as an available and attractive chiral source to design and prepare privileged ligands or catalysts.

Twice as good: The title reaction using the tryptophan‐derived bifunctional organic catalyst 1has been developed. The reported method led to the synthesis of chiral γ‐substituted butenolides in excellent yields, with high diastereo‐ and enantioselectivities. Facile synthesis of chiral glycerol derivatives containing a tertiary hydroxy group has also been demonstrated.

Doppelt gut: Die Titelreaktion mit dem von Tryptophan abgeleiteten difunktionellen Organokatalysator 1ermöglicht die Synthese chiraler γ‐substituierter Butenolide in ausgezeichneten Ausbeuten und mit hohen Diastereo‐ und Enantioselektivitäten. Darüber hinaus wird die einfache Synthese chiraler Glycerolderivate mit einer tertiären Hydroxygruppe vorgestellt.

A highly enantioselective Friedel–Crafts alkylation of indoles with α,β‐unsaturated aldehydes with excellent enantioselectivities (up to >99 % ee) has been developed, and this improved method offers substantial advantages over traditional approaches, not only by avoiding the use of acids or bases, but also in terms of the higher level of stereoselectivity. In addition, we have demonstrated through a plausible mechanism that the role of silicon in the diarylprolinol silyl ethers (Jørgensen–Hayashi organocatalyst) not only serves as a bulky group to induce steric repulsion but also serves as a Lewis acidic promoter to accelerate the reaction between the secondary amine and the substrate (α,β‐unsaturated aldehyde).

Carbamates were reacted in one pot with aromatic aldehyde and ketones at ambient temperature in the presence of catalytic amount of Zr(OTf)4 to furnish the corresponding N-protected β-amino-β-aryl ketones in good yields.

The term ‘divergent catalysis’ describes different catalytic chemical reactions that occur with the same substrates (reactants) under controllable conditions, especially using different catalysts. Various substrates were found to work with versatile reactivity under different catalytic conditions, resulting in the formation of different products. However, the examples of rationally designed divergent catalysis are still few. This review is focused on the achievements of divergent catalysis with the simplest substrates in the past decades. It includes divergent catalysis of one-component and two-component reactions with the same and simple reagents, ranging from carbon-carbon-forming pinacol coupling, benzoin condensation, Ullmann coupling, C-H homocoupling or activation, ring-closing metathesis, cyclization, Stetter reaction, Baylis-Hillman reaction, Friedel-Crafts reaction, C-H Heck coupling, 1,2-additon reaction and Michael addition, to the carbon-heteroatom bond-forming C-N cross coupling, hydroamination reaction, aza-Michael reaction, C-H oxidative amination, acetalization, and esterification.

The ionic liquids functionalized mesoporous materials were prepared and they exhibited high and dramatic catalytic activity in the aza-Michael addition of amines and NH-containing heterocycles to α,β- unsaturated carbonyl compounds. Recycling of the catalyst in these reactions was carried out and the catalyst could be used at least five times without significant loss in activity.

The Biginelli reaction between an aromatic aldehyde, ethyl acetoacetate, and urea – catalyzed by polymer-supported, re-usable, room-temperature ionic liquids (RTIL) such as 1b – was shown to efficiently proceed in glacial AcOH at 100° to afford the corresponding pyrimidine-5-carboxylates 3 in yields up to 99% within 2 4;h (Table 4;2). The catalyst(s) could be reused at least five times, basically without loss of activity, which makes this transformation not only straight-forward, but also considerably less expensive compared to methods involving classical RTIL catalysts.

β-Amino carbonyl functionalities are ubiquitous motifs in natural and nonnatural products such as alkaloids and poly-ketides. Among the reactions for the synthesis of β-amino car-bonyl compounds and β-substituted β-amino acids, aza-Michael reactions using catalytic amounts of chiral Lewisacids might provide the best methods for the generation of optically active β-amino carbonyl compounds. During the last five years, the asymmetric aza-Michael reaction has emerged as a very powerful tool for the synthesis of chiral β-amino carbonyl compounds, as will be discussed in this microreview. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)