3678-71-5Relevant academic research and scientific papers
Synthesis of Di- and Triarylmethanes through Palladium-Catalyzed Reductive Coupling of N -Tosylhydrazones and Aryl Bromides
Xia, Yamu,Hu, Fangdong,Xia, Ying,Liu, Zhenxing,Ye, Fei,Zhang, Yan,Wang, Jianbo
, p. 1073 - 1086 (2017/02/24)
A palladium-catalyzed reductive coupling between N-tosylhydrazones and aryl bromides has been developed. The reaction provides an efficient method for the synthesis of diarylmethanes and triarylmethanes via the formation of C(sp2)-C(sp3) single bonds. This new methodology for the synthesis of diarylmethanes and triarylmethanes is featured by the ready availability of the starting materials, mild reaction conditions, and the tolerance of wide range of functional groups. The reaction follows a pathway including palladium carbene formation, migratory insertion, and reduction of the alkylpalladium(II) intermediate.
NiXantphos: A deprotonatable ligand for room-temperature palladium-catalyzed cross-couplings of aryl chlorides
Zhang, Jiadi,Bellomo, Ana,Trongsiriwat, Nisalak,Jia, Tiezheng,Carroll, Patrick J.,Dreher, Spencer D.,Tudge, Matthew T.,Yin, Haolin,Robinson, Jerome R.,Schelter, Eric J.,Walsh, Patrick J.
supporting information, p. 6276 - 6287 (2014/05/20)
Although the past 15 years have witnessed the development of sterically bulky and electron-rich alkylphosphine ligands for palladium-catalyzed cross-couplings with aryl chlorides, examples of palladium catalysts based on either triarylphosphine or bidentate phosphine ligands for efficient room temperature cross-coupling reactions with unactivated aryl chlorides are rare. Herein we report a palladium catalyst based on NiXantphos, a deprotonatable chelating aryldiphosphine ligand, to oxidatively add unactivated aryl chlorides at room temperature. Surprisingly, comparison of an extensive array of ligands revealed that under the basic reaction conditions the resultant heterobimetallic Pd-NiXantphos catalyst system outperformed all the other mono- and bidentate ligands in a deprotonative cross-coupling process (DCCP) with aryl chlorides. The DCCP with aryl chlorides affords a variety of triarylmethane products, a class of compounds with various applications and interesting biological activity. Additionally, the DCCP exhibits remarkable chemoselectivity in the presence of aryl chloride substrates bearing heteroaryl groups and sensitive functional groups that are known to undergo 1,2-addition, aldol reaction, and O-, N-, enolate-α-, and C(sp2)-H arylations. The advantages and importance of the Pd-NiXantphos catalyst system outlined herein make it a valuable contribution for applications in Pd-catalyzed arylation reactions with aryl chlorides.
Modular synthesis of triarylmethanes through palladium-catalyzed sequential arylation of methyl phenyl sulfone
Nambo, Masakazu,Crudden, Cathleen M.
, p. 742 - 746 (2014/01/23)
Triarylmethanes, which are valuable structures in materials, sensing and pharmaceuticals, have been synthesized starting from methyl phenyl sulfone as an inexpensive and readily available template. The three aryl groups were installed through two sequential palladium-catalyzed C-H arylation reactions, followed by an arylative desulfonation. This method provides a new synthetic approach to multisubstituted triarylmethanes using readily available haloarenes and aryl boronic acids, and is also valuable for the preparation of unexplored triarylmethane-based materials and pharmaceuticals. Unsymmetric triarylmethanes have been synthesized starting from methyl phenyl sulfone as an inexpensive and readily available template. The three aryl groups were installed through two sequential palladium-catalyzed C-H arylation reactions, followed by an arylative desulfonation. Copyright
Palladium-catalyzed diarylmethyl C(sp3)-C(sp2) bond formation: A new coupling approach toward triarylmethanes
Xia, Ying,Hu, Fangdong,Liu, Zhenxing,Qu, Peiyuan,Ge, Rui,Ma, Chen,Zhang, Yan,Wang, Jianbo
, p. 1784 - 1787 (2013/06/26)
Palladium-catalyzed reductive coupling reactions between N-tosylhydrazones and aryl halides lead to the formation of C(sp3)-C(sp2) bonds. This approach provides a general route for the synthesis of triarylmethanes.
Superacid-catalyzed reactions of pyridinecarboxaldehydes
Klumpp, Douglas A.,Zhang, Yiliang,Kindelin, Patrick J.,Lau, Siufu
, p. 5915 - 5921 (2007/10/03)
A variety of pyridinecarboxaldehydes are shown to give condensation products in high yields (80-99%, 10 examples) by reacting with benzene and CF3SO3H (triflic acid). In the superacidic solution, pyridinecarboxaldehydes can react with deactivated arenes (o-dichlorobenzene and nitrobenzene) and with saturated hydrocarbons (methylcyclohexane and adamantane). Dicationic intermediates from pyridinecarboxaldehydes in superacid (FSO3H-SbF5) have been directly observed using low temperature 13C NMR spectroscopy. Diprotonated pyridinecarboxaldehydes have also been studies using ab initio computational methods.
Method of regulating the growth of aquatic weeds with pyridine derivatives
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, (2008/06/13)
A method of regulating the growth of submerged and floating aquatic weeds which comprises adding a 3-substituted pyridinemethane, pyridinemethanol, or derivative thereof, to a body of water containing the submerged and floating aquatic weeds to be regulated, in quantities sufficient to regulate the growth of the said submerged and floating aquatic weeds. The disclosure also relates to novel compositions for carrying out the method.
