87034-69-3Relevant academic research and scientific papers
Ligand Promoted Olefination of Anilides for Indirectly Introducing Fluorinated Functional Groups via Palladium Catalyst
Wang, Dongjie,Xu, Xu,Zhang, Jingyu,Zhao, Yingsheng
, p. 2696 - 2705 (2021/02/27)
We report a palladium-catalyzed, ligand promoted, C-H fluorine-containing olefination of anilides with 4-bromo-3,3,4,4-tetrafluorobutene as the fluorinated reagent, which has a potential transformation into other compounds due to its -CF2CF2Br functional group. -CF2CF2H was obtained by using the mild reducing agent sodium borohydride. Bioactive compounds such as aminoglutethimide derivative and propham were well-tolerated in this reaction, both of which highlight the synthetic importance of this method.
Molybdenum and Tungsten Alkylidyne Complexes Containing Mono-, Bi-, and Tridentate N-Heterocyclic Carbenes
Elser, Iris,Groos, Jonas,Hauser, Philipp M.,Koy, Maximilian,Van Der Ende, Melita,Wang, Dongren,Frey, Wolfgang,Wurst, Klaus,Meisner, Jan,Ziegler, Felix,K?stner, Johannes,Buchmeiser, Michael R.
supporting information, p. 4133 - 4146 (2019/11/03)
New tungsten and molybdenum alkylidyne complexes bearing mono-, bi-, and tridentate N-heterocyclic carbenes (NHCs) have been synthesized. Formation of unprecedented structures in complexes bearing N-tert-butyl substituents on the imidazol(in)-2-ylidene was observed, leading to molybdenum complexes containing an abnormal carbene (Mo-4) and a bridging O,C,C-pincer ligand (Mo-10) and to a tungsten complex containing a cationic imidazolinium-tagged alkoxide forming an inner salt with an anionic tungsten center (W-5). Both the abnormal carbene binding in Mo-4 and the O,C,C-pincer-type structure of Mo-10 were confirmed by single-crystal X-ray analysis, and the proposed structure of W-5 is supported by the single-crystal X-ray structure of a minor byproduct (W-8) formed during the synthesis of W-4, displaying the aforementioned inner-salt-like structure. The novel alkylidyne complexes were also investigated for their capability to form a previously postulated quasi-cationic species with a weakly coordinating anion (WCA) during the alkyne homometathesis of 1-phenyl-1-propyne. Overall, incorporation of bidentate and strongly σ donating NHCs as well as introduction of better leaving groups did not lead to the expected increase in catalytic activity. Despite identical ligand spheres, changing from molybdenum to tungsten led to complete loss of activity in the bidentate systems.
Tethered NHC Ligands for Stereoselective Alkyne Semihydrogenations
Pape, Felix,Teichert, Johannes F.
supporting information, p. 2470 - 2482 (2017/05/22)
A copper(I)-catalyzed semihydrogenation of internal alkynes has been developed. A variety of oxygen- and nitrogen-tethered N-heterocyclic carbene (NHC) complexes have been investigated, leading to a highly Z-selective transformation. The catalyst is generated from inexpensive copper(I) chloride in situ and allows catalytic semihydrogenation down to 10 bar H2.
Practical synthesis of functionalized 1,5-disubstituted 1,2,4-triazole derivatives
Xu, Yingju,McLaughlin, Mark,Bolton, Emily N.,Reamer, Robert A.
supporting information; experimental part, p. 8666 - 8669 (2011/02/28)
A general approach for the synthesis of 1,5-disubstituted-1,2,4-triazole compounds is described. A series of new oxamide-derived amidine reagents can be accessed in excellent yield with minimal purification necessary. Typically, these amidine reagents are stable crystalline solids and in certain cases were found to exist in a cyclic form as determined by NMR spectroscopy. Under optimized conditions, the direct reaction of these prepared reagents with various hydrazine hydrochloride salts efficiently generates the target triazoles. Both aromatic and aliphatic hydrazines react readily with the amidine reagents under very mild reaction conditions, delivering desired 1,5-disubstituted-1,2,4-triazole derivatives in good yields.
The intramolecular sp2 and sp3 C-H bond activation of (p-cymene)ruthenium(ii) N-heterocyclic carbene complexes
Zhang, Congying,Zhao, Yang,Li, Bin,Song, Haibin,Xu, Shansheng,Wang, Baiquan
experimental part, p. 5182 - 5189 (2009/10/31)
The intramolecular sp2 and sp3 C-H activated products, as well as the monometalated products, based on the "(p-cymene)Ru(NHC)" framework were synthesised by treatment of a series of NHCs (1-R-3-methylimidazol-2-ylidene [R = Ph (1), Bn (2), t-Bu (3), i-Pr (4), Mes (5), Cy (6)] and 1,3-bis(isopropyl)imidazol-2-ylidene (7)) with [(p-cymene)RuCl2]2 under mild conditions. A new NHC precursor (1-tert-butyl-3-phenyl-4,5-dihydro-imidazol-2-ylidene) was also designed to compare the reactivity of sp2 C-H and sp3 C-H bonds upon cyclometalation, and only the sp3 C-H activated product (8) was observed. The factors that possibly determine the selectivity of intramolecular sp2 or sp3 C-H activation are elucidated by a series of experiments. In the cases where activation of both sp2 C-H and sp3 C-H is possible, steric factors overrode the others to dominate the regioselectivity of activation. All complexes were characterised by 1H NMR, 13C NMR and HRMS spectra. The molecular structures of 1, 3, 5, 6, 7, and 8 were confirmed by X-ray diffraction.
Synthesis, crystal structure, and insecticidal activity of novel N-alkyloxyoxalyl derivatives of 2-arylpyrrole
Zhao, Yu,Mao, Chunhui,Li, Yongqiang,Zhang, Pengxiang,Huang, Zhiqiang,Bi, Fuchun,Huang, Runqiu,Wang, Qingmin
experimental part, p. 7326 - 7332 (2010/06/11)
Two series of novel N-alkyloxyoxalyl derivatives of 2-arylpyrrole were synthesized, and their structures were characterized by 1H NMR spectroscopy, elemental analysis, and single-crystal X-ray diffraction analysis. The insecticidal activities of the new compounds were evaluated. The results of bioassays indicated that some of these title compounds exhibited excellent insecticidal activities, and their insecticidal activities against oriental armyworm, mosquito, and spider mite are comparable to those of the commercialized Chlorfenapyr.
Design and synthesis of new bidentate alkoxy-NHC ligands for enantioselective copper-catalyzed conjugate addition
Clavier, Hervé,Coutable, Ludovic,Toupet, Lo?c,Guillemin, Jean-Claude,Mauduit, Marc
, p. 5237 - 5254 (2007/10/03)
A new family of chiral alkoxy-N-heterocyclic carbene (NHC) ligands has been designed for the enantioselective copper-catalyzed conjugate addition of dialkylzincs to enones. These new bidentate NHC ligands were synthesized in high overall yields using a five-step procedure starting from commercially available β-aminoalcohols. Influence of the temperature, base, solvent and copper source were studied in order to optimize the stereoselectivity of the addition. High reactivity and excellent enantioselectivity were obtained at ambient temperature with a range of cyclic enones and dialkylzinc. Addition to acyclic enones has also been studied.
