RESUMO
The present work reports synthesis, characterization and theoretical insights on novel hydroxymethyl-bishomocubanone derivatives. Twelve new bishomocubanes (BHCs) were synthesized and fully characterized by various spectroscopic techniques and single crystal X-ray analysis. The densities of the title compounds were found in the range of 1.34-1.59 g/cm3. Density-functional theory (DFT) based calculations at B3LYP/6-311++G(d,p) level of theory were performed on ten selected BHC based cage compounds. Propulsive and ballistic properties of newly synthesized hydroxymethyl-bishomocubanone derivatives in solid and liquid propulsion systems were calculated, and the results suggested that these compounds are superior to conventional fuel RP1 and binder HTPB. The detonation parameters revealed that these compounds are not explosive in nature and safe to use as solid propellants. Furthermore, kinetic and thermal stabilities of the title compounds were determined by HOMO-LUMO energy gap, ESP maps, impact sensitivity (h50) and bond dissociation energies (BDEs) followed by thermogravimetric analysis (TGA) and differential thermogravimetry analysis (DTA). Three compounds, a dinitroazide (Isp,vac= 310.98s), a dinitrate (Isp,vac = 309.51s), and a dinitronitrate (Isp,vac= 309.20s) were found to be excellent candidates for volume limited applications.
RESUMO
A synthetic approach to quinindoline derivatives by the Cu-catalyzed dual cyclization has been developed. This catalytic reaction is a practical method for the systematic synthesis of quinindoline core structure, which contains a limited-step synthetic strategy and can tolerant a wide variety of substituents. In addition, the mechanistic study reveals that the reaction initiates from a Lewis acid accelerated addition of aniline to nitrile and provides the indole substructure, and then the subsequent Cu-catalyzed C-N coupling reaction furnishes the quinoline subunit and affords the quinindoline structure.
Assuntos
Cobre/química , Quinolinas/síntese química , Compostos de Anilina/química , Catálise , Técnicas de Química Sintética , Ciclização , Elétrons , Indóis , Ácidos de Lewis/química , Estrutura Molecular , Nitrilas/química , Oxindóis/química , Quinolinas/químicaRESUMO
A novel procedure for the Pd-catalyzed dual annulation reaction to synthesize the norneocryptolepine derivatives involving the concerted construction of two central heterocycles is reported. The further methylation of the norneocryptolepine to afford its alkaloid analog neocryptolepine implies that synthesis of various neocryptolepine derivatives is feasible. The oxidative addition of Pd(0) is indicated as the key step to activate the intramolecular addition of nitrile according to the mechanism study.
RESUMO
Easily reachable electron-poor/rich primary and secondary benzylic phosphates are suitably used as substrates for Friedel-Crafts benzylation reactions with only 1.2 equiv activated/deactivated arenes (no additional solvent) to access structurally and electronically diverse polyarylated alkanes with excellent yields and selectivities at room temperature. Specifically, diversely substituted di/triarylmethanes are generated within 2-30 min using this approach. A wide number of electron-poor polyarylated alkanes are easily accomplished through this route by just tuning the phosphates.
RESUMO
A range of α-aryl substituted γ-ketophosphonates is synthesised by Lewis acid mediated reactions of 1,3-diketones and easily accessible, inexpensive benzylic α-hydroxyphosphonates in an operationally simple method under solvent-free conditions without exclusion of air/moisture. A regioselective C-C bond cleavage for 1,3-diketones in a tandem fashion has also been demonstrated. Synthesis of a γ-ketophosphonate with phenol functionality at the α-position (structural analogue of raspberry ketone, a natural product) has also been presented.
