3319-99-1Relevant articles and documents
Palladium-catalyzed cross-coupling reactions of organomercurials with organic halides
Bumagin, N. A.,More, P. G.,Beletskaya, I. P.
, p. 231 - 234 (1989)
Organomercurials, (A)2Hg (A = 5-methyl-2-furyl, thienyl) react with organic halides, ArI, in the presence of a palladium catalyst and iodide ion under argon to give cross-coupled products AAr, in high yields.
Platinum and palladium complexes of thienylpyridine. I. Compounds containing metal-carbon bonds
Giordano,Rasmussen, Paul G.
, p. 1628 - 1634 (1975)
Complexes of divalent platinum and palladium with 2-(2′-thienyl)pyridine (TP) have been investigated. In this paper we describe the syntheses and structures of those derivatives which form a metal-carbon σ bond by the spontaneous loss of a hydrogen from an aromatic group (TP-H). The reaction of TP with PtX42- (X = Br-, I-) yields orange crystalline Pt(TP)(TP-H)X. In these complexes, one TP acts as a monodentate N donor and the other as an N-C chelate, through the thienyl ring. A yellow, crystalline palladium analog Pd(TP)(TP-H)NO3 can be prepared by the reaction of TP with AgNO3 and PdI42-. All of these complexes are monomers and nonelectrolytes in nonpolar solvents. The crystal structure of iodo[2-(2′-thienyl)pyridine][2-(2′-thienyl)pyridyl]platinum(II) was determined from three-dimensional single-crystal X-ray diffraction data collected by counter methods. The complex Pt(C9H7NS)(C9H6NS)I was found to crystallize in the monoclinic space group P21/n with a = 17.360 (3) A?, b = 8.418 (1) A?, c = 13.556 (2) A?, β = 110.53 (2)° Z = 4 molecules/cell. The structure was refined by block diagonal and full matrix methods to a final R factor of 4.6% for 2220 nonzero reflections. The platinum atom is coordinated by two pyridyl nitrogens trans to one another, a thienyl carbon, and an iodide which lies slightly below the plane formed by the platinum and the other three coordinating atoms. The Pt-N distances are 2.04 (1) and 2.02 (1) A? for the nitrogens in the monodentate and the chelated ligands, respectively; the Pt-I and Pt-C distances are 2.68 (1) and 1.97 (2) A?, respectively. The free thiophene ring (not coordinated to the metal by a metal-carbon σ bond) is in an axial position. This ring was found to be disordered by 180° rotation about the pyridine-thiophene bond. The Pt-S distance (2.99 (3) A?) was nevertheless determined with reasonable accuracy and was found to be less than the sum of the van der Waals radii. The line between the platinum and the sulfur makes an angle of ca. 15° with the normal to the equatorial plane at the platinum site. The visible-ultraviolet spectra of these complexes resemble the spectra of five-coordinate d8 complexes and the ir spectra show a shifted thiophene band assigned to the thiophene ring in the axial position. These spectral results are interpreted with respect to metal-thiophene axial interaction. The metal to carbon σ bond forms with unusual ease under wet, aerobic conditions due to the thiophene ring reactivity and the chelate stability.
Dual effect of halides in the stille reaction: In situ halide metathesis and catalyst stabilization
Verbeeck, Stefan,Meyers, Caroline,Franck, Philippe,Jutand, Anny,Maes, Bert U. W.
, p. 12831 - 12837 (2010)
Halide anions can increase or decrease the transmetallation rate of the Stille reaction through in situ halide metathesis. Although the influence of the halogen present in oxidative addition complexes on the transmetallation rate with organostannanes was already known, the application of in situ halide metathesis to accelerate cross-coupling reactions with organometallic reagents is not described in the literature yet. In addition a second unprecedented role of halides was discovered. Halide anions stabilize the [Pd0(L) 2] catalyst in Stille reactions, by means of [Pd0X(L) 2]? formation (X=Cl, I), hereby preventing its leaching from the catalytic cycle. Both arene (iodobenzene) and azaheteroarene (2-halopyridine, halopyrazine, 2-halopyrimidine) substrates were used.
Microwave-assisted palladium catalysed C-H acylation with aldehydes: Synthesis and diversification of 3-acylthiophenes
Jiménez-Aberasturi, Xabier,Leicea, Eztizen,Lete, Esther,Lete, Marta G.,Santiago, Carlos,Sotomayor, Nuria
supporting information, p. 852 - 861 (2022/02/03)
The use of MW allows the efficient palladium(ii)-catalysed C-3 acylation of thiophenes with aldehydes via C(sp2)-H activation for the synthesis of (cyclo)alkyl/aryl thienyl ketones (43 examples). Compared to standard thermal conditions, the use of MW redu
N- Heterocyclic carbene palladium complex with butterfly structure and application thereof (by machine translation)
-
Paragraph 0088-0098, (2020/05/30)
N - Heterocyclic carbene palladium complex, with a butterfly structure prevents aromatic amine from encircling carbon-nitrogen bond upset, and in a steric hindrance C11 framework structure to inhibit C12 coupling reaction, between nitrogen-containing heterocyclic chlorine and low-activity nitrogen-containing heterocyclic boronic acid and reaction can be carried out β - under mild conditions of air and water at the same time to ensure higher reaction yield, The present invention also greatly improves the reaction activity, Suzuki - Miyaura of the catalyst. (by machine translation)
Multicomponent Aromatic and Benzylic Mannich Reactions through C?H Bond Activation
Xavier, Tania,Rayapin, Corinne,Le Gall, Erwan,Presset, Marc
supporting information, p. 13824 - 13828 (2019/11/03)
Multicomponent Mannich reactions through C?H bond activation are described. These transformations allowed for the straightforward generation of densely substituted benzylic and homo-benzylic amines in good yields. The reaction involves a reaction between two transient species: an organometallic species, generated by transition-metal-catalyzed sp2 or sp3 C?H bond activation and an in situ generated imine. The use of an acetal as an aldehyde surrogate was found essential for the reaction to proceed. The process could be successfully applied to RhIII-catalyzed sp2 C?H bond functionalization and extended to CuII-catalyzed sp3 C?H bond functionalization.
Copper-catalyzed cross-coupling of aryl-, primary alkyl-, and secondary alkylboranes with heteroaryl bromides
Bergmann, Allison M.,Oldham, Adam M.,You, Wei,Brown, M. Kevin
supporting information, p. 5381 - 5384 (2018/06/01)
A method for the Cu-catalyzed cross-coupling of both aryl and alkylboranes with aryl bromides is described. The method employs an inexpensive Cu-catalyst and functions for a variety of heterocyclic as well as electron deficient aryl bromides. In addition, aryl iodides of varying substitution patterns and electronic properties work well.
Accessing Heterobiaryls through Transition-Metal-Free C-H Functionalization
Banik, Ananya,Paira, Rupankar,Shaw, Bikash Kumar,Vijaykumar, Gonela,Mandal, Swadhin K.
, p. 3236 - 3244 (2018/03/23)
Herein we report a transition-metal-free synthetic protocol for heterobiaryls, one of the most important pharmacophores in the modern drug industry, employing a new multidonor phenalenyl (PLY)-based ligand. The current procedure offers a wide substrate scope (24 examples) with a low catalyst loading resulting in an excellent product yield (up to 95%). The reaction mechanism involves a single electron transfer (SET) from a phenalenyl-based radical to generate a reactive heteroaryl radical. To establish the mechanism, we have isolated the catalytically active SET initiator, characterizing by a magnetic study.
Theoretical and experimental characterization of 1,4-N?S σ-hole intramolecular interactions in bioactive N-acylhydrazone derivatives
Pinheiro, Pedro De Sena Murteira,Rodrigues, Daniel Alencar,Alves, Marina Amaral,Tinoco, Luzineide Wanderley,Ferreira, Glaucio Braga,De Sant'Anna, Carlos Mauricio Rabello,Fraga, Carlos Alberto Manssour
supporting information, p. 497 - 505 (2017/12/28)
Sigma-hole (σ-hole) bonds are interactions that are gaining special attention in medicinal chemistry. This type of interaction, initially assigned to the halogens (group 17 of the periodic table), has been extended to atoms of groups 14, 15 and 16. Sulfur atoms have been outstanding for describing these interactions at the intramolecular level (to induce conformational stability) and the intermolecular level (participating in molecular recognition of bioactive compounds by their respective targets). Thus, this work describes the theoretical and experimental characterization of a 1,4-N?S σ-hole intramolecular interaction in the N-acylhydrazone cardioactive prototype LASSBio-294 (1), which leads to conformational stabilization and has a direct influence on the molecular properties of this inotropic prototype compared to a negative control for the interaction, LASSBio-897 (2), which is the regioisomer at the thiophene ring. Our theoretical results were reached using the B3LYP/6-311G(d) level of theory, including analysis of conformational, orbital and electrostatic properties. We performed experimental studies using IR, Raman, UV and NMR spectroscopies, which corroborated our theoretical data, showing significant differences between LASSBio-294 (1) and LASSBio-897 (2) in relation to the bond strength of the groups involved in the N?S interaction (S-C and NC bonds), the energies of the orbitals associated with the S lone pair (Lp(S)) and the antibonding NC π bond (π?(NC)), as well as the 15N chemical shifts in both systems. Together, our results show how this unusual interaction can influence the molecular properties of some organic compounds.
Method for synthesizing 2-(2-thiophene)pyridine
-
Paragraph 0025; 0027, (2017/02/24)
The invention relates to a method for synthesizing 2-(2-thiophene)pyridine. The method employs 2-cyano-thiophene and acetylene gas to generate 2-(2-thiophene)pyridine under conditions of 0.5 MPa-2.1 MPa and 110-210 DEG C and under catalysis effect of organic cobalt. The generated 2-(2-thiophene)pyridine is subjected to subsequent processing refining to obtain the 2-(2-thiophene)pyridine product with purity of 98% or more. The organic cobalt is selected from cobaltocene or dicyclopentadiene cobalt. The method has the advantages of simple process and strong operationality, and the prepared product has the advantages of high purity, high yield and stabilization.
