127029-79-2Relevant articles and documents
Pd0-Catalyzed Four-Component Reaction of Aryl Halide, CO, N-Tosylhydrazone, and Amine
Liu, Yiyang,Zhang, Zhen,Zhang, Songnan,Zhang, Yan,Wang, Jianbo,Zhang, Zhenhua
, p. 3658 - 3663 (2018)
A Pd0-catalyzed four-component cascade reaction of an aryl halide, CO, an N-tosylhydrazone, and an amine affording α-amino ketone has been developed. This reaction involves a sequential carbonylation, metal carbene migratory insertion, and amination. Control experiments and DFT calculations further reveal the reaction sequence and chemoselectivity of individual components in this cascade process.
Palladium-catalyzed benzylic C(sp3)-H carbonylative arylation of azaarylmethyl amines with aryl bromides
Hu, Bowen,Walsh, Patrick J.,Xu, Lijin,Zhao, Haoqiang
, p. 10862 - 10870 (2021/08/25)
A highly selective palladium-catalyzed carbonylative arylation of weakly acidic benzylic C(sp3)-H bonds of azaarylmethylamines with aryl bromides under 1 atm of CO gas has been achieved. This work represents the first examples of use of such weakly acidic pronucleophiles in this class of transformations. In the presence of a NIXANTPHOS-based palladium catalyst, this one-pot cascade process allows a range of azaarylmethylamines containing pyridyl, quinolinyl and pyrimidyl moieties and acyclic and cyclic amines to undergo efficient reactions with aryl bromides and CO to provide α-amino aryl-azaarylmethyl ketones in moderate to high yields with a broad substrate scope and good tolerance of functional groups. This reaction proceeds via in situ reversible deprotonation of the benzylic C-H bonds to give the active carbanions, thereby avoiding prefunctionalized organometallic reagents and generation of additional waste. Importantly, the operational simplicity, scalability and diversity of the products highlight the potential applicability of this protocol.
Unusual redox behavior in the photoinduced electron-transfer reactions of amino ketones
Bergmark, William R.,Dewan, Charlotte,Whitten, David G.
, p. 8810 - 8812 (2007/10/02)
Irradiation of a wet benzene solution of 1,2-diphenyl-2-piperidino-l-ethanone and 9,10-dicyanoanthracene leads to the formation of benzil and deoxybenzoin. We have interpreted these products as arising from deprotonation leading to net oxidation coupled with reductive elimination. The latter pathway is noteworthy in that we show reductive elimination of an electron donor can be a chief consequence of photochemical single electron transfer (SET) quenching.
Singlet oxygen mediated fragmentation of amino alcohols, 1,2-diamines, and amino ketones
Haugen, Christian M.,Bergmark, William R.,Whitten, David G.
, p. 10293 - 10297 (2007/10/02)
Irradiation of aerated solutions of singlet oxygen sensitizers such as Rose Bengal, Rose Bengal derivative, or palladium tetraphenylporphyrin in the presence of substituted amines (amino alcohols, 1,2-diamines, and amino ketones) results in oxidative fragmentation of the amine in good chemical yield and with low-to-moderate quantum efficiency. For the amino alcohols and 1,2-diamines the reaction course is similar to that initiated by irradiation of electron-transfer "sensitizers" such as thioindigo or cyanoaromatics. In these cases the reaction has been shown to proceed via single electron transfer oxidation of the amine and subsequent cleavage of the amine cation radical. A similar mechanism is proposed for the reaction with singlet oxygen sensitizers in which singlet oxygen initiates reaction by SET oxidation of the amine donors and subsequent reaction from the resulting superoxide-amine cation ion radical pair. For reaction with amino ketones under the same conditions, irradiation results in formation of novel fragmentation products incorporating oxygen. Labeling studies with O-18 enriched oxygen indicate that air is the source of certain of the incorporated oxygen in the products and suggest a mechanism closely related to the other fragmentation processes.
