New stable neutral radical with intramolecular hydrogen bonding: synthesis and characterization of 2,5,8-tri-tert-butyl-7-hydroxy-6-oxophenalenoxyl

A new stable neutral radical with intramolecular hydrogen bonding, 2,5,8-tri-tert-butyl-7-hydroxy-6-oxophenalenoxyl, was synthesized from the corresponding dihydroxyphenalenone and isolated as a stable solid under air atmosphere at room temperature. The structure was unequivocally determined by means of IR spectra, ESR/ENDOR techniques, and DFT calculations.     

Synthesis and Structure of Perchloro-1λ5,3λ5-diphosphetane

Russian Journal of General Chemistry -     

Stereoselective Synthesis of Tris-endo-tricyclo [5.2.1.04,10]decane-2,5,8-triamine

The title compound has been stereoscelectively obtained by a two-step process involving the catalytic hydrogenation of triketone 2 in the presnece of benzylamine with a partially deactivated catalyst.     

Novel C3V-symmetric tripodal scaffold, triethyl cis,cis,cis-2,5,8- tribenzyltrindane-2,5,8-tricarboxylate, for the construction of artificial receptors

[reaction: see text] A novel C3V-symmetric scaffold, trindane 7, has been efficiently synthesized from 1,3,5-tris(bromomethyl)-2,4,6-tris(chloromethyl)benzene (1) in six steps with 47% overall yield. The control of all-syn stereochemistry in the tribenzylation step has been achieved by blocking one side of the trindane ring as metal carbonyl complexes. The potential utility of trindane 7 as a receptor skeleton has been examined with a urea derivative 12 toward several anionic guests.     

Synthesis of tricyclo(5.2.1.04,10)decane-2,5,8-trione from deslongchamps's diketone

Tricyclo(5.2.1.0^4,10)decane-2,5,8-trione (1) has been synthesized by base-induced cyclization of intermediates of type A readily available from Deslongchamps's diketone 2.     

Nitrogen-rich carbon nitride network materials via the thermal decomposition of 2,5,8-triazido-s-heptazine

This report describes the rapid and slow thermal decomposition of an energetically unstable polycyclic and heterocyclic azide, triazido-s-heptazine (C6N16), to produce nitrogen-rich CNx materials (x > 1.2). An analysis of gaseous byproducts shows that this large heterocyclic precursor releases primarily N2 gas during its decomposition. The product composition and its morphology are dependent on the rapidity of the TAH decomposition. The CNx products are thermally stable to 500 degrees C and exhibit variations in H and O content dependent on precursor preparation and atmospheric exposure. The rapid decomposition of TAH leads to visibly porous powders, while slow decomposition yields smooth monoliths that are reminiscent of the morphology of the starting polycrystalline powder. IR and NMR spectral similarities between the amorphous CNx products and several previously reported heptazine molecules and extended heptazine networks supports significant retention of heptazine motif in these amorphous carbon nitride extended materials.     

Promising solvent of 12,12-diethyl-2,5,8-trioxa-12-silatetradecane for lithium secondary battery

A novel partly silanized ether solvent of 12,12-diethyl-2,5,8-trioxa-12-silatetradecane is proposed for Li/organo-sulfide or Li/S battery in this paper. It is superior to other ether solvent in high boiling point, high flash point and thus resulted high safety. The conductivity of it-contained electrolyte was measured to be 5.7 × 10⁻⁴ S/cm at 25 °C, which meets the requirement for practical application. Anodic polarization curve of it-contained electrolyte attests to its strong resistivity to electro-oxidation, and AC impedance measurement also approves that it has a good compatibility with lithium electrode. Cycling test of Li/1 M LiTFSI in 12,12-diethyl-2,5,8-trioxa-12-silatetradecane/PABTH cell indicates a good utilization of the active material in the new electrolyte system.     

Improved Synthesis of Tricyclo (5.2.1.04,10) Decane-2,5,8-Trione by a Pauson-Khand Intramolecular Bis-Annulation

The title compound 1 has been synthesized from diol 3a, either directly or after protection of the two hydroxy groups as benzyl ethers, by an intramolecular Pauson-Khand bis-annulation, followed by catalytic hydrogenation and oxidation in overall yields ranging from 15% (free diol) to 35% (dibenzyl ethers).     

The synthesis of kermesic acid by acetylation-aided tautomerism of 6-chloro-2,5,8-trihydroxynaphtho-1,4-quinone

Methodology has been sought towards obtaining a 2-chloro-1,4-naphthoquinone bearing hydroxyl groups in the adjoining ring for obtaining either kermesic or carminic acids. In the first of these objectives, kermesic acid has been synthesised from 6-chloro-2,5,8-trihydroxynaphtho-1,4-quinone by the regioselective cycloaddition of the 1,2-diacetate formed by its acetylation-aided tautomerism and cycloaddition with (E)- and (Z)-3-alkoxycarbonyl-2,4-bis(trimethylsilyloxy)penta-1,3-dienes. The parent unacetylated quinone resists cycloaddition.