71093-80-6Relevant academic research and scientific papers
Sulphonic acid functionalized porphyrin anchored with a: Meso -substituted triazolium ionic liquid moiety: A heterogeneous photo-catalyst for metal/base free C-C cross-coupling and C-N/C-H activation using aryl chloride under visible light irradiation
Bhansali, Karan,Raut, Subodh,Barange, Shital,Bhagat, Pundlik
, p. 19690 - 19712 (2020/12/04)
We report an easy process to synthesize sulphonic acid functionalized porphyrin, anchored with a meso-substituted triazolium ionic liquid moiety (SAFPTILM) for metal/base free C-C cross-coupling and C-N/C-H activation using aryl chloride under visible light irradiation. The acid strength has been measured based on the Hammett indicator. The SAFPTILM photocatalyst comprising 18 π-conjugated electronic systems with the chromophore substituents in the meso-position can provide rapid electronic conducting channels during photocatalysis under the irradiation of visible light. It was found that SAFPTILM is an efficient photocatalyst for the Heck, Sonogashira, Buchwald, Ullmann/Fittig coupling and C-H activation of phenols with different aryl chlorides in the absence of a base/noble metal, using 5 W LED (yellow) light under ambient conditions. The photocatalyst with low band gap (1.55 eV) comprising conjugation, favors coupling reaction of unactivated aryl chlorides, by easy excitation of electrons and transfer to the conjugated benzimidazolium based phenylenediamine support delaying the recombination of photoinduced electron-hole pairs.
An Annelated Mesoionic Carbene (MIC) Based Ru(II) Catalyst for Chemo- And Stereoselective Semihydrogenation of Internal and Terminal Alkynes
Bera, Jitendra K.,Choudhury, Joyanta,Das, Shubhajit,Dutta, Indranil,Pati, Swapan K.,Saha, Sayantani,Yadav, Suman
, p. 3212 - 3223 (2020/10/02)
The catalytic utility of [RuL1(CO)2I2] (1), containing an annelated π-conjugated imidazo-naphthyridine-based mesoionic carbene (MIC) ligand (L1), is evaluated for E-selective alkyne semihydrogenation. The precatalyst 1, in combination with 2 equiv of AgBArF, semihydrogenates a broad range of internal alkynes with molecular hydrogen (5 bar) in water. (E)-Alkenes are accessed in high yields, and a number of reducible functional groups are tolerated. A chelate MIC ligand and two cis carbonyls provide a well-defined platform at the Ru center for hydrogenation and isomerization. The loss of two iodides and the presence of two carbonyls render the Ru center electron deficient and thus the formation of metal vinylidenes with terminal alkynes is avoided. This is leveraged for the semihydrogenation of terminal alkynes by the same catalytic system in isopropyl alcohol. Reaction profile, isomerization, kinetic, and DFT studies reveal initial alkyne hydrogenation to a (Z)-alkene, which further isomerizes to an (E)-alkene via metal-catalyzed Z → E isomerization.
Photocatalyst-free visible light promoted: E → Z isomerization of alkenes
Xu, Jianbin,Liu, Na,Lv, Haiping,He, Chixian,Liu, Zining,Shen, Xianfu,Cheng, Feixiang,Fan, Baomin
supporting information, p. 2739 - 2743 (2020/06/17)
A simple and green method of visible light driven photocatalytic E to Z isomerization of alkenes has been developed. A variety of (Z)-alkenes can be prepared in the presence of visible light, without any additional photocatalyst. This protocol features photocatalyst-free conditions, which are mild, tolerant, and operationally simple, and is easy to implement.
Monodisperse nickel-nanoparticles for stereo- and chemoselective hydrogenation of alkynes to alkenes
Murugesan, Kathiravan,Alshammari, Ahmad S.,Sohail, Manzar,Beller, Matthias,Jagadeesh, Rajenahally V.
, p. 372 - 377 (2019/01/26)
Here, we report the use of monosaccharides for the preparation of novel nickel nanoparticles (NP), which constitute selective hydrogenation catalysts. For example, immobilization of fructose and Ni(OAc)2 on silica and subsequent pyrolysis under inert atmosphere produced graphitic shells encapsulated Ni-NP with uniform size and distribution. Interestingly, fructose acts as structure controlling compound to generate specific graphitic layers and the formation of monodisperse NP. The resulting stable and reusable catalysts allow for stereo- and chemoselective semihydrogenation of functionalized and structurally diverse alkynes in high yields and selectivity.
Triazine Functionalized Porous Covalent Organic Framework for Photo-organocatalytic E- Z Isomerization of Olefins
Bhadra, Mohitosh,Kandambeth, Sharath,Sahoo, Manoj K.,Addicoat, Matthew,Balaraman, Ekambaram,Banerjee, Rahul
supporting information, p. 6152 - 6156 (2019/05/02)
Visible light-mediated photocatalytic organic transformation has drawn significant attention as an alternative process for replacing thermal reactions. Although precious metal/organic dyes based homogeneous photocatalysts have been developed, their toxic and nonreusable nature makes them inappropriate for large-scale production. Therefore, we have synthesized a triazine and a keto functionalized nonmetal based covalent organic framework (TpTt) for heterogeneous photocatalysis. As the catalyst shows significant absorption of visible light, it has been applied for the photocatalytic uphill conversion of trans-stilbene to cis-stilbene in the presence of blue light-emitting diodes with broad substrate scope via an energy transfer process.
Semireduction of Alkynes Using Formic Acid with Reusable Pd-Catalysts
Iwasaki, Riku,Tanaka, Eikichi,Ichihashi, Toshinari,Idemoto, Yasushi,Endo, Kohei
, p. 13574 - 13579 (2018/11/02)
The treatment of PdCl2 with K2CO3 and HCO2H in dioxane gives black precipitates, which are an effective catalyst for the semireduction of alkynes to alkenes using formic acid as a reductant. Even 0.05 mol % Pd promoted the reduction reaction of tolane in high yield with high selectivity.
Synthesis and catalytic activities of 1-alkoxycarbonyl- and 1-carbamoylmethyl-5-phenyl-3-aryl-3H-imidazol-1-yliden-Pd(II) complexes
Koruk?u, Meliha ?etin,Co?kun, Necdet
, p. 47 - 56 (2017/02/05)
4-Phenyl-1-aryl-1H-imidazoles were reacted with α-haloesters and amides to give the corresponding imidazolium salts. The latter were used as starting materials for the synthesis of Pd(NHC) complexes. The catalytic activities of the newly prepared compounds were screened in a model coupling reaction. 1-Alkoxycarbonyl-5-phenyl-3-aryl-3H-imidazol-1-yliden-Pd(II) were shown to be better catalyst than the 1-carbamoylmethyl-5-phenyl-3-aryl-3H-imidazol-1-yliden-Pd(II) complexes. The catalysts were shown to be insensitive to the air oxygen and water.
Application of quinoxaline based diimidazolium salt in palladium catalyzed cross-coupling reactions
Siddiqui, Mujahuddin M.,Waheed, Mohammed,Bhat, Sajad A.,Balakrishna, Maravanji S.
, p. 879 - 884 (2015/08/06)
Abstract The reaction of 2,3-bis(bromomethyl)quinoxaline with imidazole afforded the quinoxaline bridged diimidazolium salt (1) in good yield. Diimidazolium salt (1) in conjunction with Pd(OAc)2 was employed as a catalyst for C-C cross-coupling reactions. The diimidazolium salt was found to be efficient in catalyzing Suzuki-Miyaura cross-coupling reaction in ethanol under ambient conditions. Moderate to good selectivity of the trans product was observed in the Heck cross-coupling reaction. The molecular structure of 1 was confirmed by single crystal X-ray diffraction study. [Figure not available: see fulltext.]
Palladium porphyrin catalyzed hydrogenation of alkynes: Stereoselective synthesis of cis -alkenes
Nishibayashi, Ryo,Kurahashi, Takuya,Matsubara, Seijiro
supporting information, p. 1287 - 1290 (2014/06/10)
(Tetraphenylporphyrin)palladium was developed as a catalyst for the chemoselective and stereoselective hydrogenation of alkynes to cis-alkenes by the syn-addition of hydrogen. Alkynes containing various functional groups were tolerated in the reaction, which gave the corresponding cis-alkenes in good to excellent yields. Georg Thieme Verlag Stuttgart New York.
Palladium tetrazole-supported complex as an efficient catalyst for the Heck reaction
He, Ying,Cai, Chun
experimental part, p. 113 - 117 (2012/02/01)
A tetrazole-supported polymeric ligand has been synthesized. The palladium complex derived from the polymeric material has been evaluated as a catalyst for the Heck reaction of aryl iodides and bromides with styrene to provide the corresponding products in high yields. The reaction proceeded smoothly in the presence of 1 mol% with respect to Pd of catalyst in DMF at 125 or 140 °C within 1-3 h. Recycling studies showed that the catalyst can be readily recovered and reused for several times without significant loss of catalytic activity. Graphical abstract: [Figure not available: see fulltext.]
