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A mild, efficient and general method for the chemospecific α-oxygenation of aldehydes is described. Treatment of a series of aldehydes with N - tert -butyl- O -benzoyl hydroxylamine hydrochloride gives the corresponding α-oxygenated carbonyl via a proposed pericyclic rearrangement process.

The first γ-radiation responsive linear supramolecular via pillararene-based host–guest recognition polymer was built successfully. What is more, this supramolecular polymer exhibited dual redox responsiveness.

A concise, enantioselective synthesis of the Phase I anticancer agent, (?)-salinosporamide A , is described. The brevity of the described strategy stems from a key bis-cyclization of a β-keto tertiary amide , accomplished on gram scale, which retains optical purity enabled by A 1,3 -strain rendering epimerization slow relative to the rate of bis-cyclization. The versatility of the strategy for derivative synthesis is demonstrated by the synthesis of (?)-homosalinosporamide A .

Simple methods for the regioselective introduction of deuterium labels at the α- and β-carbon atoms of leucine using a Co( III ) imino acid complex are described which have a general applicability to the synthesis of a range of labelled amino acids.

An efficient Co-catalyzed 1,4-addition reaction of alkyl/aryl triflates and tosylates with activated alkenes is described. In this reaction, an air-stable cobalt( II ) complex, a mild reducing agent Zn and a simple proton source (H 2 O) are used. A radical mechanism for the addition of alkyl tosylates to activated alkenes is likely involved.

The syntheses of [Bu t PAs(NMe 2 ) 2 K . pmedta] 2 1 and [{CyNAs(NMe 2 ) 2 K} 2 ] ∞ 2 from the reactions of [As(NMe 2 ) 3 ] with Bu t PH 2 and CyNH 2 , respectively, in the presence of potassiated bases exemplify a general approach to multifunctional secondary phosphide and amide anions containing variable sets of group 15 donor centres.

Highly mono-dispersed CdSe–CdS core–shell nanoparticles have been prepared by a novel method in which [Cd{Se 2 CNMe( n Hex)} 2 ] (250 °C for 30 min) and [Cd{S 2 CNMe( n Hex)} 2 ] (250 °C for a further 30 min) are thermolysed in tri- n -octylphosphine oxide (TOPO) in a ‘one pot’ synthesis; the core–shell structure has been characterized by electronic spectroscopy, photoluminescence, X-ray diffraction and electron microscopy (SAED, SEM and TEM).

Two common radical anion reductants, potassium benzophenone ketyl (K(Ph 2 CO)) and potassium naphthalenide (K 2 (C 10 H 8 ) 2 (THF)), have been isolated and characterized for the first time in solvent -free form or with low solvent content, allowing their use as pure solid reactants in preparative redox chemistry in accurate stoichiometric amounts.

We report here the fabrication of a p–n junction diode in a single nanostructure by synthesizing a heterostructure involving n-type AgInS 2 and p-type Ag 2 S. The quasi type-II band alignment between these ternary–binary semiconductors in the p–n junction heterostructures also slows down the carrier recombination rate and the heterostructures show rectification behavior. Hence, they can be used as an active material for fabrication of bulk heterojunction photovoltaic devices without any additional semiconductor material or dye required for charge separation or formation of a p–n junction.

Co 2+ ions encapsulated in nitrogen doped graphene were applied as an oxygen evolution catalyst. Their redox potentials were tuned using different counter anions as liable ligands, and the redox potential related catalytic rates were explored. It was proposed that the electron density of Co 2+ ions was a general descriptor for activity.