Cu/nitroxyl catalysts have been identified that promote highly efficient and selective aerobic oxidative lactonization of diols under mild reaction conditions using ambient air as the oxidant. The chemo- regioselectivity may be tuned by changing identity nitroxyl cocatalyst. A Cu/ABNO catalyst system (ABNO = 9-azabicyclo[3.3.1]nonan-N-oxyl) shows excellent reactivity with symmetrical hindered unsymmetrical diols, whereas a Cu/TEMPO (TEMPO 2,2,6,6-tetramethyl-1-piperidinyl-N-oxyl) displays...

As a finite-energy-bandgap alternative to graphene, semiconducting molybdenum disulfide (MoS2) has recently attracted extensive interest for energy and sensor applications. In particular broad-spectral photodetectors, multilayer MoS2 is more appealing than its monolayer counterpart. However, little understood regarding the physics underlying photoresponse of MoS2. Here, we employ scanning photocurrent microscopy identify nature generated in transistors. The generation transport are found...

A series of 2-dialkylphosphino-2'-alkoxy-1,1'-binaphthyl ligands (6a−c and 8a−c) have been prepared conveniently by a lithium-initiated ring-opening reaction dinaphthofuran, followed selective phosphorylation. These compounds displayed remarkable air moisture stability, both in solid form solution. Application these phosphine palladium-catalyzed C−N bond forming reactions revealed the crucial roles steric bulk substituents on phosphorus atom governing catalytic activity. Specifically,...

A visible-light-induced radical cascade cyclization of 2-isocyanoaryl thioethers for the synthesis 2-CF2/CF3-containing benzothiazoles has been developed. Sodium sulfite can participate in photocatalytic cycle as a reductant that efficiently transforms Ir4+ into Ir3+ to promote fluoroalkylation under mild reaction conditions.

A visible-light-driven regioselective dearomative cyclization between 2-benzyl-2-bromomalonate and alkynes under mild conditions leading to the formation of spiro[4,5]decanes has been developed. In presence H2O, a variety 2-benzyl-2-bromomalonates smoothly undergo 5-exo-dig radical with afford corresponding in moderate good yield step-economical manner oxidant-free conditions.

An efficient intramolecular dearomative cyclization<italic>via</italic>visible light-induced photoredox catalysis allows for a highly regioselective cyclization of α-bromo-<italic>N</italic>-benzyl-alkylamides to construct 2-azaspiro[4.5]decanes in the presence an iridium catalyst.

Abstract C 20 H 7 Cl 2 F 8 N 5 O 3 S, monoclinic, P 1 / n (no. 14), a = 7.78993(14) Å, b 11.8299(2) c 25.8640(5) β 93.1491(17)°, V 2379.87(7) Å , Z 4, R gt ( ) 0.0540, wR ref 0.1306, T 100 K.

This review summarizes the recent developments in transition metal-catalyzed 1,n-enyne cyclization reactions that have been reported literature from January 1, 2002 to April 30, 2005. The cyclizations described herein include four parts according reaction mechanism, i. e. initiated by oxidative cyclometallation; activation of triple bond form a vinyl metal species; electrophilic bond; and double bond. Enyne do not follow above mechanism are included. Keywords: E-double bond, activation,...

Various substituted aryl-pyridyl ketones were hydrogenated in the presence of Ru-XylSunPhos-Daipen bifunctional catalytic system with enantiomeric excesses up to 99.5%. Upon introduction a readily removable ortho-bromo atom phenyl ring, enantiomerically enriched 4-chlorophenylpyridylmethanol was obtained by hydrogenation method 97.3% ee, which provided an important chiral intermediate for some histamine H(1) antagonists.

A one-step construction of quinoline-fused lactones was achieved by visible-light-induced photocatalytic aerobic oxidation/Povarov cyclization reaction. This method provides a new access to the synthesis important fused heterocycles under mild reaction conditions.

A visible-light-induced photocatalytic intermolecular dearomative cyclization of 2-bromo-1,3-dicarbonyl compounds and alkynes afforded biologically important spirocarbocycle structures in moderate to good yields via a 5-exo-dig radical under mild reaction conditions. 5.0 mmol scale dearomatization proceeded smoothly with 95% yield even when the catalyst loading was reduced 0.1 mol %, suggesting that this method suitable for large-scale synthesis.

We report a simple and effective nickel-based catalytic system, NiCl2·6H2O/tBuOK, for the electrophilically activated hydrosilylation of terminal alkenes with primary silanes. This protocol provides excellent performance under mild reaction conditions: exclusive anti-Markovnikov selectivity, broad functional group tolerance (36 examples), good scalability (TON = 5500). However, secondary tertiary silanes are not suitable. Mechanistic studies revealed that this homogeneous includes an Si–H...

Dynamic kinetic resolution of various α-amido-β-keto phosphonates via asymmetric hydrogenation proceeded efficiently to give the corresponding β-hydroxy-α-amido in high diastereo- and enantioselectivities (up 99:1 syn/anti, 99.8% ee). The addition catalytic amounts CeCl3·7H2O is necessary achieve both good selectivity efficiency under mild reaction conditions.

A thin Al2O3 dielectric film was directly grown onto graphene layers without any surface treatment prior to H2O-based atomic layer deposition for the first time. The growth mechanism of has been studied by changing temperature and purge We found that morphology influenced amount distribution physically adsorbed precursor molecules on graphene, especially H2O molecules. Within an optimal window, conformal uniform films were obtained as confirmed force microscopy transmission electron results....

Palladium-catalyzed intermolecular C-N bond-forming reactions between aryl halides and amides are described using 2-dialkylphosphino-2'-alkoxyl-1,1'-binaphthyl, which is both bulky electron-rich, as the ligand. A variety of amides, including aliphatic aromatic primary lactams, carbamates, were viable substrates for amidation, exhibited good functional group compatibility. By tuning substituents at 2,2'-position 1,1'-binaphthyl ligand, palladium-catalyzed amidation was realized this coupling...

A highly efficient intramolecular selective aryl migration/desulfonylation of 2-bromo-N-aryl-N-(arenesulfonyl)amide via visible light-induced photoredox catalysis has been accomplished. This approach allows for the construction a variety multisubstituted N,2-diarylacetamide under mild reaction conditions.

A general and efficient visible-light-induced CF2 radical-based cascade reaction of o-hydroxyaryl enaminones has been described. This protocol afforded the corresponding functionalized 3-CF2-containing chromones in generally good yields under mild conditions. The use NaHSO3, which both basicity reducibility, efficiently suppressed formation two byproducts, 4H-chromen-4-one 3-bromo-4H-chromen-4-one.

A visible-light-induced radical cascade cyclization of aryl isonitriles and cyclobutanone oxime esters for the synthesis cyclopenta[b]quinoxalines has been accomplished first time. The key to success this process was integration in situ-formed nitrile followed by isonitrile/nitrile insertion-cyclization. easy introduction substituents both substrates high functional group tolerance reaction make it an efficient strategy give various quinoxaline derivatives moderate good yields.

Abstract Potassium hydroxide‐catalyzed hydrosilylation exhibits excellent activity and chemoselectivity for the reduction of cyclic imides under mild reaction conditions. The system may be readily tuned by changing identity stoichiometry hydrosilanes: a polymethylhydrosiloxane (PMHS)/potassium hydroxide resulted in various to corresponding ω‐hydroxylactams 70–94% yield, while diphenylsilane (Ph 2 SiH )/potassium selectively afforded aryl lactams 33–95% yield. These catalytic protocols...

A series of enantiomerically pure γ-heteroatom substituted β-hydroxy esters were synthesized with high enantioselectivities (up to 99.1% ee) by hydrogenation β-keto in the presence Ru-(S)-SunPhos catalyst. These asymmetric hydrogenations provide key building blocks for a variety naturally occurring and biologically active compounds.

A highly efficient addition of alkyl α-bromocarboxylates to enamines by visible light-induced photoredox catalysis is reported. Compared with traditional methods, the reaction described here provided an alternative route for construction valuable γ-ketoesters in generally good yields.

Highly effective asymmetric hydrogenation of β-ketophosphonates in the presence Ru-(S)-SunPhos as catalyst was realized; good to excellent enantioselectivities (up 99.9% ee) and diastereoselectivities (96:4) were obtained.