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In order to analyze the reaction mechanism between N,N‐dimethyl‐2‐azide‐ethylamine (DMAZ) and nitrogen tetroxide (NTO), a stable conformation of DMAZ molecule was first searched. Then, the changes of the potential energy and the products generated in the simulation process were analyzed by the reaction molecular dynamics. Finally, the potential energy surface, reaction rate constant and activation energy of H atom abstraction were calculated based on density functional theory. The results show that the stable conformation of DMAZ looks like a scorpion. In the simulation, the potential energy of the system increased sharply in the endothermic reaction, and then decreased in the exothermic chemical reaction. Compared with N,N,N',N'‐tetramethyl ethylenediamine (TMEDA), the reaction speed of DMAZ/NTO was higher, and the energy released was also higher. The reaction products of DMAZ/NTO and TMEDA/NTO were mainly H2O, N2 and CO2.With the increase of temperature, the rate constant of H atom abstraction increased exponentially. The rate of increase in path H3(it means that NO2 reacts with the H3 atom of DMAZ) was much higher than that of path H14 (it means that NO2 reacts with the H14 atom of DMAZ). The activation energies of H atom abstraction in path H3 and H14 were 16.60 kJ mol−1 and 61.08 kJ mol−1 respectively. [ABSTRACT FROM AUTHOR]

Nine types of diversely fused heterocyclic quaternary ammonium salts were constructed through an oxidative CH annulation reaction. Both high-valent pentamethylcyclopentadienylcobalt(III) and pentamethylcyclopentadienyliridium(III) were found to be effective as catalyst for this reaction. Broad substrate scope and good functional group tolerance were observed. [ABSTRACT FROM AUTHOR]

A novel noncovalent strategy to construct chemically synthesized vaccines has been designed to trigger a robust immune response and to dramatically improve the efficiency of vaccine preparation. Glycosylated MUC1 tripartite vaccines were constructed through host-guest interactions with cucurbit[8]uril. These vaccines elicited high levels of IgG antibodies that were recognized by transformed cells and induced the secretion of cytokines. The antisera also mediated complement-dependent cytotoxicity. This noncovalent strategy with good suitability, scalability, and feasibility can be applied as a universal strategy for the construction of chemically synthesized vaccines. [ABSTRACT FROM AUTHOR]

Described herein is a manganese-catalyzed dehydrogenative [4+2] annulation of NH imines and alkynes, a reaction providing highly atom-economical access to diverse isoquinolines. This transformation represents the first example of manganese-catalyzed CH activation of imines; the stoichiometric variant of the cyclomanganation was reported in 1971. The redox neutral reaction produces H2 as the major byproduct and eliminates the need for any oxidants, external ligands, or additives, thus standing out from known isoquinoline synthesis by transition-metal-catalyzed CH activation. Mechanistic studies revealed the five-membered manganacycle and manganese hydride species as key reaction intermediates in the catalytic cycle. [ABSTRACT FROM AUTHOR]

A series of 5-arylisoxazole (II) and related pyrazole derivatives (III) are synthesized via ultrasound assisted reactions of 3-aminopropenone (I) with hydroxylamine or hydrazine hydrate, respectively. [ABSTRACT FROM AUTHOR]

Reaction of isonitriles with 3-(arylamino)isobenzofuran-1(3H)-ones in the presence of a catalytic amount of an octahydro (R)-binol-derived chiral phosphoric acid affords 3-oxo-2-arylisoindoline-1-carboxamides in high yields with good to high enantioselectivities. [ABSTRACT FROM AUTHOR]

A convenient microwave promoted three‐component domino reaction of β‐ketoamides (I), pentandial (II), and malononitrile (III) is developed to give deca‐ and octahydroisoquinolines (IV) and (VI). [ABSTRACT FROM AUTHOR]

The reaction has a good functional group tolerance and can be scaled up. [ABSTRACT FROM AUTHOR]

22 Title compounds of type (III) or (IV) are prepared in relatively short reaction times. [ABSTRACT FROM AUTHOR]

The synthesis of a large variety of the desired heterocyclic structures becomes possible under microwaves with high regio- and chemoselectivity. [ABSTRACT FROM AUTHOR]

This unusual reaction is performed in tetrahydrofuran which is split during the reaction in an unprecedented manner under conditions used, leading to the formation of two geminal C-C bonds via C-H and C-O cleavage. [ABSTRACT FROM AUTHOR]

Reductive cyclization of nitroaryl substrates using a low valent titanium reagent allows the synthesis of the title compounds (II) and (IV). [ABSTRACT FROM AUTHOR]

The one-pot transformation involves the formation of four new C-C and two new C-N bonds, as well as the construction of three new rings with efficient use of all reactants. [ABSTRACT FROM AUTHOR]