Transition-metal-free oxidative cyclization reaction of enynals to access pyrane-2-one derivatives.

A novel and efficient metal-free C-H functionalization of enynals is developed to synthesize α-pyrone derivatives via the formation of two C-O bonds. In this project, KSO has been introduced as an efficient oxygen source and C-H functionalization agent in regioselective oxidative cyclization reaction with a relatively broad substrate scope.

Isocyanide-based consecutive Bargellini/Ugi reactions: an efficient method for the synthesis of pseudo-peptides containing three amide bonds.

Isocyanide-based consecutive Bargellini/Ugi multicomponent reactions as a combinatorial strategy have been developed for the synthesis of new class of pseudo-peptides. Via Bargellini reaction 3-carboxamido-isobutyric acids are prepared using acetone, chloroform, sodium hydroxide, and isocyanides. Then, using Ugi multicomponent reaction strategy, pseudo-peptides containing three amide bonds are synthesized using the Bargellini reaction product, aldehydes, amines, and isocyanides.

Fabrication of blue organic light-emitting diodes from novel uranium complexes: synthesis, characterization, and electroluminescence studies of uranium anthracene-9-carboxylate complexes.

In this study, three uranium(vi) complexes, [UO2(C15H9O2)2(CH3CH2OH)2]·2CH3CH2OH (1), [U2O4(C15H9O2)2(CH3O)2(CH3OH)2]·2CH3OH (2), and [U2O4(C15H9O2)4(CH3OH)2]·2H2O (3), were prepared by reacting anthracene-9-carboxylic acid with uranyl acetate dihydrate using various ligand to uranyl acetate ratios in different solvents. The infrared and UV-Vis spectra along with elemental and thermal analyses showed the formation of mono- and dinuclear anthracene-9-carboxylate complexes of uranium. A 1 to 3 molar ratio of uranyl acetate to anthracene-9-carboxylic acid in ethanol resulted in the formation of the mononuclear complex 1, whereas a 1 to 2 and 1 to 3 molar ratio of uranyl acetate to anthracene-9-carboxylic acid in methanol produced the dinuclear complexes 2 and 3, respectively.

Metal-Organic Frameworks via Emissive Metal-Carboxylate Zwitterion Intermediates.

Pyridinemethanol-carboxylate esters form octahedral complexes with Zn(NO ) in aqueous DMF that subsequently undergo hydrolysis at elevated temperatures to form metal-carboxylate zwitterions. In situ deprotonation of the hydroxy group leads to thermally robust, neutral MOFs. This stepwise synthesis can be controlled by temperature and is made possible by the subtle difference in reactivity of the functional groups.

Metal-Organic Frameworks via Emissive Metal-Carboxylate Zwitterion Intermediates.

This month's cover is dedicated to the golden anniversary of Singapore by the collaborating groups of Wen-Hua Zhang of the IMRE, Singapore, and T. S. Andy Hor of the NUS, Singapore, and two more groups from Monash University, Malaysia, and Soochow University, P.

One-pot four-component synthesis of highly substituted [1,2,4]triazolo[1,5-a]pyrimidines.

A green one-pot four-component strategy has been developed for the synthesis of [1,2,4]triazolo[1,5-a]pyrimidine-6-carboxamide derivatives using an amine, 2,2,6-trimethyl-4H-1,3-dioxin-4-one, an aldehyde, and 3-amino-1,2,4-triazole in the presence of a catalytic amount of p-toluenesulfonic acid in water within 4-6 h.

1,5-Dichloro-4,8-dinitro-anthraquinone.

The ring skeleton of the title compound, C(14)H(4)Cl(2)N(2)O(6), is close to planar (r.m.s.

1,5-Dicyano-anthraquinone.

The complete mol-ecule of the title compound, C(16)H(6)N(2)O(2), which is generated by a crystallographic inversion centre, is almost planar (r.m.s.

1,8-Dihydr-oxy-2,4,5,7-tetra-nitro-9,10-anthraquinone.

The ring system in the title compound, C(14)H(4)N(4)O(12), is essentially planar (r.m.s.

Aqua-chloridodimethyl-phenyltin(IV)-15-crown-5 (2/1).

The Sn(IV) atom in the title compound, 2[Sn(CH(3))(2)(C(6)H(5))Cl(H(2)O)]·C(10)H(20)O(5), exists in a trans-C(3)SnClO trigonal bipyramidal geometry in which the organo substituents occupy the equatorial sites. The coordinated water mol-ecule forms two hydrogen bonds to the 15-crown-5 mol-ecule, which is disordered about a center of inversion.