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11.
Prabhu Suma Mutalik Srinivas Rai Sharada Udupa Nayanabhirama Rao Bola Sadashiva Satish 《Journal of nanoparticle research》2015,17(10):1-22
Journal of Nanoparticle Research - Superparamagnetic iron oxide nanoparticles (SPIONs) are evolving as a mainstay across various applications in the field of Science and Technology. SPIONs have... 相似文献
12.
A highly efficient and mild protocol for the synthesis of imidazo-fused polyheterocycles via Groebke–Blackburn–Bienaymè reaction under the influence of catalytic amount of lanthanum chloride heptahydrate has been described. A wide range of nitrogen-enriched polyheterocycles are synthesized with high yields under neat conditions. 相似文献
13.
Sharada DS Muresan AZ Muthukumaran K Lindsey JS 《The Journal of organic chemistry》2005,70(9):3500-3510
[reaction: see text] Palladium porphyrins are valuable photosensitizers and luminescent agents in biology and materials chemistry. New methodology is described wherein a 1-acyldipyrromethane is converted into the palladium chelate of a trans-A(2)B(2) porphyrin via a one-flask reaction. The reaction entails self-condensation of the 1-acyldipyrromethane in refluxing ethanol containing KOH (5-10 mol equiv) and Pd(CH(3)CN)(2)Cl(2) (0.6 mol equiv) exposed to air. This direct route to palladium porphyrins is more expedient than the four steps of the traditional synthesis: (1) reduction of the 1-acyldipyrromethane; (2) acid-catalyzed condensation; (3) oxidation of the porphyrinogen intermediate; and (4) metal insertion. The new synthesis requires neither acid nor DDQ and formally entails only a 2e(-) + 2H(+) oxidation overall versus the traditional multistep synthesis which requires a 2e(-) + 2H(+) reduction per each 1-acyldipyrromethane (4e(-) + 4H(+) overall) followed by a 6e(-) + 6H(+) oxidation. The analogous reaction of a 1,9-diacyldipyrromethane and a dipyrromethane also gives the palladium porphyrin. Seven palladium porphyrins have been prepared in yields of 25-57%. The direct route also can be used with Cu(OAc)(2).H(2)O to give the copper porphyrin albeit in low yield. In summary, this methodology readily affords palladium porphyrins directly from acyldipyrromethanes. 相似文献
14.
The synthesis of [a]-annelated pyrazolopyrroloindoles via intramolecular 1,3-dipolar cycloaddition of in situ generated azomethine imine from N-allylated indole-2-carboxaldehyde, in regio- and stereoselective manner by using microwave irradiation is described. A one-pot strategy for the expedient synthesis of pyrazolopyrroloindoles has been developed. 相似文献
15.
The observed oscillatory linewidths of theV′=3 level ofB
3Π0+ state of I35Cl and I37Cl are explained as due to heterogeneous predissociation caused by the crossing of an unstableZ
1Π state. The crossing point and the slopes of the curves have been fixed to predict the observed linewidths. 相似文献
16.
Kuppuswamy Nagarajan Vunnam R. Rao Rashmi K. Shah Sharada J. Shenoy Hans Fritz Wilhelm J. Richter Dieter Muller 《Helvetica chimica acta》1988,71(1):77-92
Homophthalic acid ( 1 ) undergoes reaction with 1,2-, 1,3-, and 1,4-diamines to give condensed 1(2H)-isoquinolinones like 2 , 4 , 13 , and 25 , which exhibit marked enamine character. These are attacked by electrophiles at the N or C terminus. Some notable reactions of imidazoisoquinolone 2 are those with maleic and acrylic acids to form the tetracycles 48 and 51 , respectively. With propiolic acid, 5 underwent an interesting reaction to form the benzimidazonaphthyridine 53 . An equally interesting behaviour was elicited from 2 in its reaction with formaldehyde, when in addition to the expected methylene-bridged molecule 59 , the novel spiro derivative 60 was formed by the dimerisation of a presumed azadiene intermediate 63 . 相似文献
17.
Kurma Srimathi Dasari Gouthami Nukala Satheesh Kumar Ravula Sharada Kandukuri Padma Bandari Srinivas 《Russian Journal of General Chemistry》2022,92(7):1326-1332
Russian Journal of General Chemistry - A series of new quinoxaline-1,2,4-thiadiazoles amide hybrids has been synthesized and evaluated for their anti-proliferative activity on four different human... 相似文献
18.
Glasses with formula 30Li2O 60B2O3xTa2O5 (10−x) Bi2O3 for x=0, 2, 4, 6 and 8 were prepared via normal melt quenching technique and characterized by refractive index and MDSC. Refractive index (μ) and glass transition temperature (Tg) are found to increase with increase in dopant concentration. Impedance spectra of the samples were recorded in the frequency range 100 Hz–5 MHz in the temperature range 175–275 °C. The plots are typical of those recorded for disordered systems. Conductivities and relaxation times are found to follow Arrhenius type of relation and activation energies are calculated. Optical absorption spectra were recorded in the wavelength range 200–900 nm range from which cutoff wavelength (λc) and optical band gap energy (Eg) are evaluated. λc is found to decrease while Eg to increase with increase in composition. FTIR spectra of the samples were recorded in the frequency range 400–1500 cm−1 which exhibit characteristic bands corresponding to BO3, BO4 stretching vibrations and BO bending vibration. Tightening of the structure is indicated by increase in the vibration of BO3 at the cost of BO4 for 8 mol% of Ta2O5. This is in support of the highest value of Tg for this sample among the series. Raman spectra of the samples were recorded in the frequency range 200–1200 cm−1. With successive addition of Ta2O5, increase in the vibration of Ta–O groups TaO6 groups to be responsible for observed increase in μ and Tg. An attempt is made to prepare tantalum doped borate glasses and study them by spectroscopic techniques. 相似文献
19.
Selective reduction of the nitro group in methyl 1-(2-nitrophenyl)-4-oxo-cyclohex-2-enecarboxylates with zinc-acetic acid forms hexahydrocarbazoles. The reaction is applicable to the corresponding pyridyl analogs to generate azahexahydrocarbazoles. This provides an efficient method for the generation of tricyclic framework.
20.
A facile and one-pot synthesis of 2-benzoxepines, from Baylis-Hillman adducts that is, alkyl 3-aryl-3-hydroxy-2-methylenepropanoates, via treatment with HCHO in the presence of concd H2SO4, involving tandem construction of C-O and C-C bonds via Prins-type and Friedel-Crafts reactions, is described. 相似文献