137058-15-2Relevant articles and documents
Palladium-Catalyzed Annulation of Internal Alkynes by Arene-Containing Vinylic Iodides and Triflates
Larock, Richard C.,Tian, Qingping
, p. 2002 - 2009 (1998)
In the presence of a palladium catalyst, internal alkynes undergo carboannulation by cyclic and acyclic vinylic iodides and triflates bearing a neighboring aromatic ring to produce a variety of carbocycles. For example, a number of 9,10-disubstituted-1,2,3,4-tetrahydrophenanthrenes have been prepared in good yields through the palladium-catalyzed annulation of internal alkynes by 2-phenyl-1-cyclohexenyl triflate (1) or l-iodo-2-phenylcyclohexene (2). This annulation process is fairly general and highly regioselective. The process appears to involve oxidative addition of the vinylic substrate to Pd(0) to produce a vinylic palladium intermediate, which adds the carbon moiety to the less hindered end and the palladium to the more hindered end of the alkyne, followed by intramolecular ring closure onto the neighboring aryl group. The scope and limitations of this methodology are discussed.
Oxidation of Nonactivated Anilines to Generate N-Aryl Nitrenoids
Deng, Tianning,Mazumdar, Wrickban,Ford, Russell L.,Jana, Navendu,Izar, Ragda,Wink, Donald J.,Driver, Tom G.
supporting information, p. 4456 - 4463 (2020/03/05)
A low-temperature, protecting-group-free oxidation of 2-substituted anilines has been developed to generate an electrophilic N-aryl nitrenoid intermediate that can engage in C-NAr bond formation to construct functionalized N-heterocycles. The exposure of 2-substituted anilines to PIFA and trifluoroacetic acid or 10 mol percent Sc(OTf)3 triggers nitrenoid formation, followed by productive and selective C-NAr and C-C bond formation to yield spirocyclic- or bicyclic 3H-indoles or benzazepinones. Our experiments demonstrate the breadth of these oxidative processes, uncover underlying fundamental elements that control selectivity, and demonstrate how the distinct reactivity patterns embedded in N-aryl nitrenoid reactive intermediates can enable access to functionalized 3H-indoles or benzazepinones.
Achieving Site Selectivity in Metal-Catalyzed Electron-Rich Carbene Transfer Reactions from N-Tosylhydrazones
Su, Naijing,Deng, Tianning,Wink, Donald J.,Driver, Tom G.
supporting information, p. 3990 - 3993 (2017/08/15)
Catalyst control of the site-selectivity of electron-rich alkyl, aryl disubstituted carbenes generated in situ from o-alkenyl-substituted N-tosylhydrazones was achieved in this study. Exposure of these substrates to copper iodide triggered the formation of α-alkoxy 2H-naphthalenones. This investigation established that changing the catalyst to a rhodium(II) carboxylate turned off cyclization and migration of the electron-rich metal carbene with the β-carboxylate and turned on allylic C-H bond functionalization to diastereoselectively afford 1H-indenes. Examination of the scope of this reaction revealed that ethereal, aminomethylene, and unactivated 2° C-H bonds could be functionalized.
