Rhodium(I) complexes of α-keto-stabilised 1,2-bis(diphenylphosphino)alkane mono ylides
Rhodium(I) complexes of the hybrid ylide-phosphine ligands, Ph2P(CH2)nPPh2(CHC(O)C6H5) (n = 1: dppm-yl, or 2: dppe-yl) have been synthesised from [Rh(μ-C1)(COD)]2 (COD = 1,5-cyclooctadiene) and characterized by NMR spectroscopic and X-ray structural methods. The dppe-yl behaves as an ambidentate ligand; it functions as a monodentate P-donor ligand with a dangling ylidic carbon in the neutral chloro complex, [(COD)Rh(Cl)(dppe-yl)] (1), whereas replacement of the chloride by a non-coordinating counter anion results in the formation of the complexes, [(COD)Rh(L-L’)]+ (L-L’ = dppe-yl (2) or dppm-yl (3)) respectively in which the ligands are bonded to the metal via the phosphorus and the ylidic carbon atoms. The 1,5-cyclooctadiene (COD), present in the Rh(I) precursor, remains intact in the products. The structures of1,2 and3 have been confirmed by X-ray crystallography.
Syntheses and 31P NMR studies of some cycloocta-1,5-dienerhodium(I) complexes containing coordinated 1,3-DI-t-butyl- 2,4-dihalogenocyclodiphosphazanes, [PXNtBu]2 (X = Cl, F) and related ligands. Crystal and molecular structure of bis(chloro)(cycloocta-1,5-diene)1,3-di-t-butyl-2,4-difluorocyclodiphos
Abstract Syntheses of several cycloocta-1,5-dienerhodium(I) complexes containing coordinated 1,3-di-t-butyl-2,4-dihalogenocyclodiphosphazanes (PXNtBu)2 (X = Cl, F) and related ligands are described. 31P NMR spectroscopic studies have established two different types of coordination mode of the ring system and their interconversion. A single crystal structure determination on [Rh2Cl2(η4-C8H12)2(PFNtBu)2] confirms the proposed structure.
Effect of pretreatment with antibiotics on the hydrolysis of salicyluric acid in rabbit intestinal microorganisms.
The effect of pretreatment with antibiotics on the hydrolysis of salicyluric acid in rabbit intestinal microorganisms was investigated. Latamoxef sodium (LMOX, 25 mg/kg/d, intravenously) and cephalexin (CEX, 16.7 mg/kg/d, orally) were administered for 1 or 3 d. The blood concentration of salicyluric acid and salicylic acid following oral, intracecal and rectal administration of salicyluric acid was determined. By the pretreatment with LMOX for 1 or 3 d, the blood concentration of salicylic acid following oral administration of salicyluric acid was slightly decreased. In rabbits pretreated with CEX for 3 d, the blood concentration of salicylic acid was detected at low concentration. By the pretreatment with LMOX and CEX, however, the decrease in the blood concentration of salicylic acid following rectal administration of salicyluric acid was not observed. Although the examination of population of intestinal microorganisms induced by the pretreatment with antibiotics was not performed, the metabolic activity of intestinal microorganisms may be changed.