1632-83-3Relevant articles and documents
Palladium-Catalyzed Ligand-Free C-N Coupling Reactions: Selective Diheteroarylation of Amines with 2-Halobenzimidazoles
Sang, Wei,Gavi, Ayao Jean,Yu, Bao-Yi,Cheng, Hua,Yuan, Ye,Wu, Yuan,Lommens, Petra,Chen, Cheng,Verpoort, Francis
, p. 129 - 135 (2020)
2-Aminobenzimidazoles are widely present in a number of bioactive molecules. Generally, the preparation of these molecules could be realized by the mono-substitution of 2-halobenzimidazoles with amines. However, rare examples were reported for the di-subs
Proton transfer from imidazole, benzimidazole, and their 1-alkyl derivatives. FMO analysis of the effect of methyl and benzo substitution
Buncel, Erwin,Joly, Helen A.,Jones, John R.
, p. 1240 - 1245 (1986)
The rate-pH profile for detritiation from the C-2 position of 1-methylimidazole has been determined in aqueous solution at 85 deg C.The profile is consistent with a mechanism involving attack by hydroxide ion on the conjugate acid of the substrate to give an ylid intermediate in the rate-determining step.At higher pH, hydroxide-catalyzed exchange of the neutral species becomes increasingly important.Comparison of the second-order rate constants derived from the rate-pH profiles of imidazole, 1-methylimidazole, benzimidazole, and 1-methylbenzimidazole showed that methyl substitution caused the rate to increase by 2- to 3-fold while benzo annelation increased the rate by 10- to 20-fold.Frontier molecular orbital (FMO) analysis of the reaction scheme for proton transfer from imidazole, benzimidazole, and their 1-alkyl derivatives has been used to explain the rate-accelerating effect of methyl substitution and benzo annelation in these processes.
Self-Assembly of Benzimidazole-Derived Tris-NHC Ligands and AgI-Ions to Hexanuclear Organometallic Cages and Their Unusual Transmetalation Chemistry
Nishad, Rajeev C.,Rit, Arnab
, p. 594 - 599 (2021)
Multi-ligand self-assembly to attain the AgI-N-heterocyclic carbene (NHC)-built hexanuclear organometallic cages of composition [Ag6(3 a,b)4](PF6)6 from the reaction of benzimidazole-derived tris(azolium) salts [H3-3 a,b](PF6)3 with Ag2O was achieved. The molecular structures of the cages were established by X-ray diffraction studies along with NMR and MS analyses. The existence of a single assembly in solution was supported by diffusion-ordered spectroscopy (DOSY) 1H NMR spectra. Further, transmetalation reactions of these self-assembled complexes, [Ag6(3 a,b)4](PF6)6, with CuI/AuI-ions provided various coinage metal-NHC complexes having diverse molecular compositions, which included the first example of a hexanuclear CuI-dodecacarbene complex, [Cu6(3 b)4](PF6)6.
A general method for the preparation of N-heterocyclic carbene-silver(I) complexes in water
Saif, Muhammad Jawwad,Flower, Kevin R.
, p. 113 - 118 (2013)
A new synthetic method leading to N-heterocyclic carbene-silver(I) complexes [(R2-NHC)2Ag]+ [AgX2] - is developed by using benzimidazolium compounds, NaOH (as a base), silver salts and water (as the reaction medium). Single-crystal X-ray structure revealed that compound 1 comprises a linear [Ag-(Et2-Bimy) 2]+ cation and a linear [AgBr2]- anion. These two ions are linked through an AgI-AgI association and staggered at an angle of 90.3.
Walther reaction in the benzazoles series and preparation of their 2-deutero derivatives
Lomov,Yutilov,Smolyar
, p. 241 - 242 (2006)
Reactions of 2-hydrazino-substituted 1-methylbenzimidazole, benzothiazole, and benzoxazole with azobenzene at 160-180°C resulted in hydrazino group elimination and formation of the corresponding 2-H-benzazoles. Under similar conditions the 2-deuterohydrazinobenzazoles prepared from 2-hydrazinobenzazoles and heavy water were converted into 2-deuterobenzazoles. Pleiades Publishing, Inc. 2006.
N-heterocyclic carbenes: VIII. Benzimidazolium diterpene salts with an oxo group in substituent
Denisov,Usatykh,Gorbunov,Maiorova,Glushkov
, p. 705 - 710 (2014)
Benzimidazolium salts with an oxo group in the substituent are synthesized from a diterpene ketone.
Cleavages of 1-Methyl-2-trimethylsilylbenzimidazole and 2-Trimethylsilylbenzothiazole in Methanol and Related Media
Seconi, Giancarlo,Eaborn, Colin
, p. 1051 - 1056 (1981)
First order rate constants k at 25 deg C have been determined for the cleavage of 1-methyl-2-trimethylsilylbenzimidazole (I) and 2-trimethylsilylbenzothiazole (II) in MeOH, alone or containing NaOMe, and in 5:2 v/v MeOH-H2O containing HClO4.Compound (I) is cleaved rapidly by neutral methanol (1E3 k 51 s-1) (and also by H2O, 1E3 k 110 s-1 or EtOH, 1E3 k 3.0 s-1); very small amounts of NaOMe do not affect the rate (which thus refers to a spontaneous process), but larger amounts induce a base-catalysed process (1E2 k 63 l mol-1s-1).The data for the neutral cleavage of (I), including a rate isotope effect, r.i.e. , of 3.3, can be interpreted either in terms of the cyclic mechanism involving a solvent molecule previously proposed for cleavage of 2-trimethylsilylpyridine or one in which MeO(1-) attacks the protonated substrate.In base cleavage (I) gives an r.i.e. of 1.1, and this is interpreted in terms of proton transfer to the N of the N=C bond synchronous with breaking of the C-SiMe3 bond, but (II) gives an r.i.e. of 0.46, suggesting that there is little if any such electrophilic assistance.The low product isotope effects (the product ratio RH/RD on cleavage in 1:1 MeOH-MeOD) of 1.2-1.3 for neutral cleavage of (I) and the base cleavages of (I) and (II) are attributed to the fact that the isotopic composition of the product is determined in a step involving transfer of hydrogen to a localized carbanion.Addition of acid greatly raises the rate of cleavage of (II) in 5:2 MeOH-H2O, but reduces it for (I), for which the rate levels off at a value thought to refer to the fully protonated species.The acid-catalysed processes may involve attack of a solvent molecule at silicon in the protonated species.
Menschutkin Reactions of N-Methylimidazole and of N-Methylbenzimidazole with Methyl Iodide in Acetonitrile-Methanol. Family-dependent and Family-independent Properties
Kondo, Yasuhiko,Izawa, Shingo,Kusabayashi, Shigekazu
, p. 1925 - 1928 (1988)
Rate constants and activation parameters have been determined for the reactions of the aromatic amines N-methylimidazole and N-methylbenzimidazole with methyl iodide in acetonitrile-methanol.The enthalpies of solution have also been determined for the relevant species in the same solvent mixtures.Activation enthalpies in acetonitrile and specific interaction enthalpies between the amine and methanol show a linear correlation with pKa values determined in water only over a narrowly defined type of structure.However, transition-state indices for the two reactions defined in terms of physical interaction energy, αphys and βphys, show the behaviour anticipated by analogy with reactions of pyridine derivatives. (i.e., family-independent character).
Kinetic analysis of the complete mechanochemical synthesis of a palladium(II) carbene complex
Allenbaugh, Rachel J.,Zachary, Jonathon R.,Underwood, A. Nicole,Bryson, J. Dillion,Williams, Joseph R.,Shaw, Angela
, (2020)
Benzimidazoline-2-ylidene complexes of palladium(II) were synthesized mechanochemically in a vibratory ball mill. Complete syntheses began with preparation of benzimidiazolium halides from commercially available starting materials. These “greener chemistr
Solid-phase synthesis of 1,2-benzophenazine and some fused imidazole derivatives
Zefirov,Sereda,Volkov,Tkachenko,Zyk
, p. 577 - 579 (1996)
The solid-phase synthesis of 1,2-benzophenazine and various N-methylbenzimidazoles using o-diaminoarenes is very promising and permits the synthesis of 1-methyl-4,5-[b]naphtho-1H-imidazole, which could not be obtained by the condensation of o-diaminoarenes with paraformaldehyde using the standard liquid-phase method. 1996 Plenum Publishing Corporation.
