A novel reaction involving tandem construction of C-N and C-C bonds via the simultaneous Ritter and Houben-Hoesch reactions on Baylis-Hillman adducts leading to a convenient, one-pot synthesis of 2-benzazepine derivatives is described. A facile stereoselective transformation of the Baylis-Hillman adducts into (E)- and (Z)-allyl amides is also presented. 相似文献
Summary Rhodium(I), iridium(I), palladium(II) and platinum(II) complexes of the phosphinoamide ligands, Ph2PCH2CONHR (R = H, HDPA; Me, MDPA; Ph, PDPA) were prepared and characterized by using conductivity data, i.r., 1H and 31P(H) n.m.r. spectral data. Reaction of the ligands with MCl(PPh3)3 and MCl(CO)(PPh3)2 (M = Rh, Ir) in CH2Cl2 under reflux lead to the formation of MCl(PPh3)2 [Ph2PCH2C(O)NHR] and MCl(CO)(PPh3)[Ph2PCH2–C(O)HNR] respectively. The reaction of either K2MCl4 or cis-MCl2(PPh3)2 affords complexes of the type cis-MCl2[Ph2PCH2C(O)NHR]2 (M = Pd, Pt). A similar product results even from the reaction of phosphinoamides with cis-platin. Possible structures are proposed for the complexes based on their physicochemical data 相似文献
The extraction and spectrophotometric determination of vanadium (V) with oxine is investigated at higher acidities than described previously. Under these conditions, n-butanol and other alcohols are found to exert a synergic effect on the extraction of vanadium into benzene. In the presence of alcohol only a 6-fold ligand excess is needed for quantitative extraction in a single operation, the acidity of the aqueous medium being 0.05M with respect to sulphuric or phosphoric acid. The interference of iron(III) in the spectrophotometric determination of vanadium is suppressed by the addition of pyrophosphate. Beer's law is obeyed up to 14.0 mug of vanadium/ml and the sensitivity is 0.008 mug of vanadium/cm(2) at 390 mmu. The composition of the extracted species is found to be vanadium:oxine:n-butanol = 1:2:2. 相似文献
Summary Three new bifunctional phosphinoamide ligands of the type Ph2PCH2C(O)NHR (R = H, HDPA; Me, MDPA; Ph, PDPA) were prepared and characterized. Their ruthenium(II) complexes prepared from two different precursors, RuCl2-(DMSO)4 and RuCl2(PPh3)3, are of similar composition and correspond to the formula, [RuCl(L)2(P-O)2]Cl (L = DMSO/PPh3; phosphinoamide). However, RuCl3-(AsPh3)2(MeOH) reacts with the phosphinoamide to yield a reduced product of the cis-RuCl2(P-O)2 type. The ligands and complexes were characterized by mass, i.r. and n.m.r. spectroscopy. Possible stereochemistries for the complexes are proposed. 相似文献
Pseudo‐first‐order reaction kinetics and binding studies of trans‐[Co(en)2(Et)H2O] complex with 1H‐imidazole, substituted 1H‐imidazoles, histidine, histamine, glycine and glycine ethyl ester were investigated by means of spectrophotometric techniques. Equilibrium constants were determined as a function of pH at 25°. Binding and kinetic studies were correlated to basicity and steric hindrance. From the equilibrium data, it was found that the entering nucleophile is participating in the transition state, an Id mechanism is proposed. The effect of the incoming ligands on the complex was studied by molecular mechanics. The interaction of trans‐[Co(en)2(Et)H2O] with CT DNA was studied spectrophotometrically. 相似文献
A novel, sensitive, stability indicating RP-LC method has been developed for the quantitative determination of mitotane, its impurity in both bulk drugs and pharmaceutical dosage forms. Efficient chromatographic separation was achieved using a C18 stationary phase with simple mobile phase combination delivered in an isocratic mode and quantitation was by ultraviolet detection at a wavelength of 230 nm. The mobile phase consisted of buffer and acetonitrile (25:75, v/v) delivered at a flow rate of 1.0 mL min−1. Buffer consisted of 10 mM potassium dihydrogen orthophosphate monohydrate, pH adjusted to 2.5 by orthophosphoric acid. In the developed LC method the resolution (Rs) between mitotane and its impurity namely Imp-1 was found to be greater than 2.5. Regression analysis shows an r value (correlation coefficient) greater than 0.999 for mitotane and its impurity. This method was capable to detect the impurity of mitotane at a level of 0.003% with respect to test a concentration of 0.2 mg mL−1 for a 10 μL injection volume. The inter- and intra-day precision values for mitotane and its impurity was found to be within 2.0% RSD. The method has shown good and consistent recoveries for mitotane in bulk drugs (99.2–101.5%), pharmaceutical dosage forms (98.2–103.1%) and for its impurity (99.7–102.1%). The test solution was found to be stable in diluent for 48 h. The drug was subjected to stress conditions of hydrolysis, oxidation, photolysis and thermal degradation. Considerable degradation was found to occur in basic stress hydrolysis. The stress samples were assayed against a qualified reference standard and the mass balance was found close to 99.97%. The developed RP-LC method was validated with respect to linearity, accuracy, precision and robustness.
A simple, mild and efficient method for deprotection of acetonides in the presence of molecular iodine is described. Acid labile protecting groups such as PMB, OMe, OBn, allyl and propargyl are compatible with the reaction conditions, while TBS, TBDPS, TMS and THP ethers were unstable under the same conditions. 相似文献
TheK-electron capture probabilities for the 1/2? → 3/2? and 1/2? → 1/2+ transitions in the decay of105Ag were measured for the first time using the sum coincidence method. The experimental PK values were estimated to be 0.824 ± 0.042 and 0.851 ±0.046 for the allowed and first-forbidden beta transitions, respectively in agreement with the theory. The PL experimental values to these two levels were also computed using the experimental PL/PK values reported by earlier authors. These results are also found to be consistent with the theoretical PL values. 相似文献