Palladium-catalyzed C(sp3)-H nitrooxylation of masked alcohols.

A palladium-catalyzed ß-C(sp3)-H nitrooxylation of aliphatic alcohols with AgNO2 is reported. An 8-formylquinoline-derived oxime is installed as an exo-type directing group for sp3 C-H activation and selectfluor acts as the oxidant. The reaction tolerates a variety of functional groups and shows good selectivity for ß-C-H nitrooxylation of alcohols.

Nitrogen-rich polycyclic pentazolate salts as promising energetic materials: theoretical investigating.

Pentazolate (cyclo-N5-) salts are nitrogen-rich compounds with great development potential as energetic materials due to their full nitrogen anion. However, the densities of available N5- salts are generally low, which seriously lowers their performances. It is necessary to screen out cyclo-N5- salts with high density. To this end, eight new non-metallic cyclo-N5- salts based on fused heterocycle were designed. -NH2, -NO2, and -O- groups were introduced into the compounds to adjust and improve the detonation performance and impact sensitivity of cyclo-N5- salts. By theoretical calculations and Hirshfeld surface analyses, the densities, heats of formation, detonation performance, sensitivities, and crystal structures of the title compounds were predicted, and the contribution of hydrogen bond as well as π-π stacking to the stability of cyclo-N5- salt was revealed. The results indicate that the densities of title compounds are higher than 1.85 g cm‒3, and the sensitivities of these compounds are predicted to be lower than that of HMX. The detonation properties of a (D = 9.47 km s-1, P = 41.21 GPa) and d (D = 9.44 km s-1, P = 40.26 GPa) are better than those of HMX. These mean that using fused ring as a cation and introducing proper substituents are an effective method to improve cyclo-N5- salt's density and balance the detonation performance and sensitivity.

Theoretical research about nonmetallic energetic salts with pentazolate anion.

Significant progress has been made in the synthesis of nitrogen-rich high-energy salts by pairing pentazolate anion (cyclo-N5-) with different cations since cyclo-N5- was synthesized. It is difficult to screen out cyclo-N5- salts with high energy quickly and effectively in experiment, while theoretical research can realize this goal. Herein, nineteen high-energy salts, which were composed of tetrazole cation and cyclo-N5- anion, were designed. And their properties were studied via density functional theory and volume-based thermodynamic methods. The results indicate that most salts have high densities, low sensitivities, and good detonation properties. In particular, salt 14 (ρCalib = 1.802 g/cm3, ΔHf = 1058.4 kJ/mol, D = 9.38 km/s, P = 39.10 GPa, h50 = 44.92 cm) exhibits excellent detonation performance (approximating that of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane (CL-20)) superior to 1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), and lower impact sensitivity than CL-20 or HMX. Hence salt 14 is regarded as promising candidates for high-performance energetic materials.

Theoretical Investigation of Energetic Salts with Pentazolate Anion.

Energetic salts based on pentazolate anion (cyclo-N5-) have attracted much attention due to their high nitrogen contents. However, it is an enormous challenge to efficiently screen out an appropriate cation that can match well with cyclo-N5-. The vertical electron affinity (VEA) of the cations and vertical ionization potential (VIP) of the anions for 135 energetic salts and some cyclo-N5- salts were calculated by the density functional theory (DFT). The magnitudes of VEA and VIP, and their matchability were analyzed. The results based on the calculations at the B3LYP/6-311++G(d,p) and B3LYP/aug-cc-pVTZ levels indicate that there is an excellent compatibility between cyclo-N5- and cation when the difference between the VEA of cation and the VIP of cyclo-N5- anion is -2.8 to -1.0 eV. The densities of the salts were predicted by the DFT method. Relationship between the calculated density and the experimental density was established as ρExpt = 1.111ρcal - 0.06067 with a correlation coefficient of 0.905. This regression equation could be in turn used to calibrate the calculated density of the cyclo-N5- energetic salts accurately. This work provides a favorable way to explore the energetic salts with excellent performance based on cyclo-N5-.

[Clinical observation on point-through-point acupuncture for treatment of cerebellar ataxia after apoplexy].

OBJECTIVE: To observe therapeutic effect of point-through-point acupuncture on cerebellar ataxia after apoplexy and evaluate the safety. METHODS: Random, parallel control, single blind and multicentral study method was used and 224 cases from 4 hospitals were divided equally into a treatment group and a control group, 112 cases in each group. The treatment group were treated with point-through-point acupuncture and the control group with general needling method. Their symptoms and signs, and the effect on transcranial Doppler's method (TCD) were investigated. RESULTS: The total effective rate was 93.3% in the treatment group which was better than 77.4% in the control group, with a significant difference between the two groups (P < 0.01), and the point-through-point acupuncture could significantly improve TCD of basilar artery, vertebral artery and posterior inferior cerebellar artery (Vs, Vm, Vd, PI, RI), superior to the control group. CONCLUSION: The point-through-point acupuncture has obvious therapeutic effect on cerebellar ataxia after apoplexy and good safety.

[Diagnosis and treatment of jugular foramen neurinomas].

OBJECTIVE: To study the clinical features and treatments of jugular foramen neurinomas. The approximate approach and proper exposure regions of jugular foramen tumour were discussed in this paper. METHODS: Fourteen cases of jugular foramen neurinomas were diagnosed by CT, MRI, DSA and 3D-CT reconstruction preoperatively. The tumours were resected by far lateral infra-temporal approach. The classification and relative operative approaches were discussed. RESULTS: Among 14 patients, total removal were achieved in 8 cases, subtotal removal in 4 cases and partial removal in the other 2 cases. All patients got good recovering. No serious complications correlating the approaches occurred except one case of facial paralysis. CONCLUSION: The far later infratentorial approach was suggested to be more suitable for surgery upon neurinomas of jugular foramen.