36800-95-0Relevant academic research and scientific papers
Electrochemical cross-coupling reactions of sodium arenesulfinates with thiophenols and phenols
Ma, Jinfeng,Xu, Pan,Zhong, Zijian,Zhou, Aihua
supporting information, (2021/10/26)
A green electrochemical oxidative cross-coupling protocol for the generation of thiosulfonates and sulfonate esters using sodium arenesulfinates and thiophenols/phenols is disclosed. The protocol involves using inorganic and non-toxic NaI as both redox catalyst and supporting electrolyte at room temperature without oxidant and base. The reactions provide good yields of products and tolerate broad substrate scope. The mechanistic studies revealed that the reactions proceed via a radical pathway for the formation of SO2–S and SO2–O bonds.
Transition-Metal-Free and Visible-Light-Mediated Desulfonylation and Dehalogenation Reactions: Hantzsch Ester Anion as Electron and Hydrogen Atom Donor
Heredia, Micaela D.,Guerra, Walter D.,Barolo, Silvia M.,Fornasier, Santiago J.,Rossi, Roberto A.,Budén, Mariá E.
supporting information, p. 13481 - 13494 (2020/12/15)
Novel approaches for N- and O-desulfonylation under room temperature (rt) and transition-metal-free conditions have been developed. The first methodology involves the transformation of a variety of N-sulfonyl heterocycles and phenyl benzenesulfonates to the corresponding desulfonylated products in good to excellent yields using only KOtBu in dimethyl sulfoxide (DMSO) at rt. Alternately, a visible light method has been used for deprotection of N-methyl-N-arylsulfonamides with Hantzsch ester (HE) anion serving as the visible-light-absorbing reagent and electron and hydrogen atom donor to promote the desulfonylation reaction. The HE anion can be easily prepared in situ by reaction of the corresponding HE with KOtBu in DMSO at rt. Both protocols were further explored in terms of synthetic scope as well as mechanistic aspects to rationalize key features of desulfonylation processes. Furthermore, the HE anion induces reductive dehalogenation reaction of aryl halides under visible light irradiation.
The Synthesis and Catalytic Activity of New Mixed NHC-Phosphite Nickel(0) Complexes
Dorta, Reto,Duczynski, Jeremy,Moggach, Stephen A.,Sobolev, Alexandre N.,Stewart, Scott G.
supporting information, (2020/01/21)
Herein we describe the synthesis and isolation of the first low-valent NHC-phosphite nickel complexes of general formula Ni(NHC)[P(OAr)3]2. These three-coordinate Ni(0) compounds were fully characterized, including by X-ray crystallography that highlighted their trigonal planar geometry. The representative complex Ni(IMes)[P(OPh)3]2 was used to show that a phosphite ligand is readily substituted in the presence of an aldehyde or nitrile. These stoichiometric studies then led to an investigation of their catalytic properties in the Suzuki-Miyaura cross-coupling reactions between aryl tosylates and aryl boronic acids, a first for such a NHC-Ni catalyst. Finally, mechanistic investigations led to the isolation of a well-defined oxidative addition product.
Palladium-Catalyzed Cyclobutanation of Aryl Sulfonates through both C-O and C-H Cleavage
Zhang, Liangwei,Liu, Long,Huang, Tianzeng,Dong, Qizhi,Chen, Tieqiao,Chen, Tieqiao
, p. 2189 - 2196 (2020/06/05)
A palladium-catalyzed cyclobutanation of aryl sulfonates with strained alkenes has been developed. The methodology is featured to achieve the cleavage of both C-O and C-H bonds of phenol derivatives in one pot. Under the reaction conditions, in addition t
Electron Donor-Acceptor Complex Enabled Decarboxylative Sulfonylation of Cinnamic Acids under Visible-Light Irradiation
Ge, Qian-Qian,Qian, Jia-Sheng,Xuan, Jun
, p. 8691 - 8701 (2019/08/30)
Visible-light-induced decarboxylative sulfonylation of cinnamic acids with aryl sulfonate phenol esters enabled by the electron donor-acceptor complex is developed. The method offers a mild and green approach for the synthesis of vinyl sulfones with excellent functional group compatibility under photocatalyst and oxidant-free conditions.
Coupling of C(sp3)-H bonds with C(sp2)-O electrophiles: mild, general and selective
Gui, Yong-Yuan,Liao, Li-Li,Sun, Liang,Zhang, Zhen,Ye, Jian-Heng,Shen, Guo,Lu, Zhi-Peng,Zhou, Wen-Jun,Yu, Da-Gang
supporting information, p. 1192 - 1195 (2017/02/05)
Herein is reported the mild and general coupling of amine/ether C(sp3)-H bonds with various kinds of C(sp2)-O electrophiles with high selectivity and efficiency. Valuable allylic/benzylic amines are generated in moderate to excellent yields. The utility of this transformation is demonstrated by a broad substrate scope (>50 examples), good functional group tolerance and facile product modification.
Copper-Catalyzed C-S Bond Formation via the Cleavage of C-O Bonds in the Presence of S8 as the Sulfur Source
Rostami, Abed,Rostami, Amin,Ghaderi, Arash,Gholinejad, Mohammad,Gheisarzadeh, Sajedeh
, p. 5025 - 5038 (2017/10/06)
Useful and applicable methods for one-pot and odorless synthesis of unsymmetrical and symmetrical diaryl sulfides via C-O bond activation are presented. First, a new efficient procedure for the synthesis of unsymmetrical sulfides using the cross-coupling reaction of phenolic esters such as acetates, tosylates, and triflates and with arylboronic acid or triphenyltin chloride as the coupling partners is reported. Depending on the reaction, S 8 /KF or S 8 /NaO t -Bu system is found to be an effective source of sulfur in the presence of copper salts and in poly(ethylene glycol) as a green solvent. Then, the synthesis of symmetrical diaryl sulfides from phenolic compounds by using S 8 as the sulfur source and NaO t -Bu in anhydrous DMF at 120 °C under N 2 is described. By these protocols, the synthesis of a variety of unsymmetrical and symmetrical sulfides become easier than the available protocols in which thiols and aryl halides are directly used for the preparation of the sulfides.
Decarbonylative Cyanation of Amides by Palladium Catalysis
Shi, Shicheng,Szostak, Michal
supporting information, p. 3095 - 3098 (2017/06/23)
Transition-metal-catalyzed cyanation of aryl halides is a process of significant importance in the preparation pharmaceuticals, organic materials and agrochemicals. Here, we demonstrate a palladium-catalyzed decarbonylative cyanation of amides by highly selective carbon-nitrogen bond cleavage for the synthesis of a wide range of aryl nitriles. The utility of this technology is demonstrated by the synthesis of isotopically labeled aryl nitriles and orthogonal cross-coupling reactions of bench-stable amides to establish cross-coupling synthons with opposite polarity.
Copper-Catalyzed Regioselective C-H Sulfonyloxylation of Electron-Rich Arenes with p-Toluenesulfonic Acid and Sulfonyloxylation of Aryl(mesityl)iodonium Sulfonates
Huang, He,Wu, Yang,Zhang, Wen,Feng, Chun,Wang, Bi-Qin,Cai, Wan-Fei,Hu, Ping,Zhao, Ke-Qing,Xiang, Shi-Kai
, p. 3094 - 3101 (2017/03/23)
Copper-catalyzed regioselective C-H sulfonyloxylation of electron-rich arenes with p-toluenesulfonic acid has been developed. Electron-rich benzene derivatives and heteroarenes can undergo this C-H sulfonyloxylation reaction to generate aryl tosylates. Furthermore, sulfonyloxylation of aryl(mesityl)iodonium sulfonates has also been investigated. Both aryl(mesityl)iodonium tosylates and triflates can react smoothly to get aryl sulfonates. The formed aryl sulfonates can be converted to phenols, as well as used as good partners of cross-coupling reactions.
METAL OXIDE CATALYZED RADIOFLUORINATION
-
Paragraph 0109, (2016/02/28)
Inter alia, the first titania-catalyzed [18F]-radiofluorination in highly aqueous medium is provided. In embodiments, the method utilizes titanium dioxide, 1 : 1 acetonitrile- thexyl alcohol solvent mixture and tetrabutylammonium bicarbonate as a base. Radiolabeling may be directly performed with aqueous [18F]fluoride without the need for drying/azeotroping step, which reduces radiosynthesis time while keeping high fluoride conversion. The general applicability of the synthetic strategy to the synthesis of the wide range of PET probes from tosylated precursors is demonstrated.
