50693-98-6Relevant academic research and scientific papers
Synthesis of a new series of Ni(II), Cu(II), Co(II) and Pd(II) complexes with an ONS donor Schiff base: Crystal structure, DFT study and catalytic investigation of palladium and nickel complexes towards deacylative sulfenylation of active methylenes and regioselective 3-sulfenylation of indoles: Via thiouronium salt formation
Devi, Namita,Sarma, Kuladip,Rahaman, Rajjakfur,Barman, Pranjit
, p. 4583 - 4595 (2018/04/03)
A series of Ni(ii), Cu(ii), Co(ii), and Pd(ii) complexes have been synthesized with a chelating Schiff base ligand coordinated to a metal center with ONS donor atoms. The ligand and complexes are characterized by elemental analysis and spectroscopic techniques like FT-IR, 1H-NMR, and UV-Visible spectroscopy. The single crystal structure of the Pd(ii) complex is obtained by X-ray diffraction analysis and exhibits slightly distorted square planar geometry. The structure is optimized by DFT, TD-DFT calculation to elaborate the electronic structure and NBO for the charge distribution analysis of the Pd(ii) complex. The synthesized Pd(ii) and Ni(ii) complexes as catalysts have been investigated in the C-S cross-coupling of indoles and active methylenes. The metal propelled regioselective transformation afforded 3-sulfenylated indoles while β-diketones favored deacylated monosulfenyl ketones in an excellent yield via thiouronium salt formation. The Pd(ii) complex displays slightly better reactivity whereas the Ni(ii) complex is cost-efficient. The method is fast, easy to handle and cost effective in terms of high reactivity of catalysts, use of non-toxic solvents, and cheaper aryl halides and thiourea replace conventional sulfur sources, providing a practical access to organic transformations.
Reaction of 3-Phenylglycidic Esters. Part 1. Stereoselective Opening of the Oxirane Ring of trans-3-Phenylglycidic Esters with 2-nitrothiophenols and the Effects of Various Catalysts Thereon
Hashiyama, Tomiki,Inoue, Hirozumi,Konda, Mikihiko,Takeda, Mikio
, p. 1725 - 1732 (2007/10/02)
In the reaction of 2-nitrothiophenol (2) with trans-3-phenylglycidic esters carrying various substituents on the benzene ring, both reactivity and stereoselectivity of the oxirane ring-opening of the glycidates were markedly influenced by the electronic nature of the substituents.The presence of electron-donating groups was favourable for both reactivity and the preferential formation of cis-opening products, while the reverse was true for electron-withdrawing groups.As a result of our investigation on the catalytic effect of various Lewis acids in the reaction of the 4-methoxy derivative (1) with (2), tin compounds were found to be effective catalysts for cis-opening and readily produced the threo-nitro ester (3a), a key intermediate for the synthesis of diltiazem (5).Isolation of the crystalline complex (adduct A) from the reaction of (2) with SnCl4 and its efficient catalytic activity similar to that of SnCl4 suggest that the transition state involves co-ordination of tin derivatives both with (2) and the epoxy oxygen of (1) to cause highly specific cis-opening.
Applicability of Hammett Equation to Kinetics of Acid-catalysed Esterification of ortho-Substituted Phenoxyacetic, Phenylmercaptoacetic and Phenylsulphonylacetic Acids by Methanol
Baliah, V.,Gurumurthy, R.
, p. 257 - 258 (2007/10/02)
Correlation analysis of the title rate data shows that the steric effects of ortho-substituents are absent at the reaction centre.
