Synthesis of Triarylmethanes via Palladium-Catalyzed Suzuki–Miyaura Reactions of Diarylmethyl Esters
作者:Amira H. Dardir、Irene Casademont-Reig、David Balcells、Jonathan D. Ellefsen、Matthew R. Espinosa、Nilay Hazari、Nicholas E. Smith
DOI:10.1021/acs.organomet.1c00085
日期:2021.7.26
compatible with systems for diarylmethyl ester coupling. Furthermore, the reaction can be performed stereospecifically to generate stereoinverted products. On the basis of DFT calculations, it is proposed that the oxidative addition of the diarylmethyl 2,3,4,5,6-pentafluorobenzoate substrate occurs via an SN2 pathway, which results in the inverted products. Mechanistic studies indicate that oxidative addition
Towards a Comprehensive Hydride Donor Ability Scale
作者:Markus Horn、Ludwig H. Schappele、Gabriele Lang-Wittkowski、Herbert Mayr、Armin R. Ofial
DOI:10.1002/chem.201202839
日期:2013.1.2
Rates of hydride transfer from several hydridedonors to benzhydrylium ions have been measured at 20 °C and used for the determination of empirical nucleophilicity parameters N and sN according to the linear free energy relationship log k20 °C=sN(N+E). Comparison of the rate constants of hydride abstraction by tritylium ions with those calculated from the reactivity parameters sN, N, and E showed fair
Palladium-Catalyzed C(sp<sup>3</sup>)–H Arylation of Diarylmethanes at Room Temperature: Synthesis of Triarylmethanes via Deprotonative-Cross-Coupling Processes
作者:Jiadi Zhang、Ana Bellomo、Andrea D. Creamer、Spencer D. Dreher、Patrick J. Walsh
DOI:10.1021/ja3047816
日期:2012.8.22
this approach is an in situ metalation of the substrate via C-H deprotonation under catalytic cross-coupling conditions, which is referred to as a deprotonative-cross-coupling process (DCCP). Base and catalyst identification were performed by high-throughput experimentation (HTE) and led to a unique base/catalyst combination [KN(SiMe(3))(2)/Pd-NiXantphos] that proved to efficiently promote the room-temperature
Modular Synthesis of Triarylmethanes through Palladium-Catalyzed Sequential Arylation of Methyl Phenyl Sulfone
作者:Masakazu Nambo、Cathleen M. Crudden
DOI:10.1002/anie.201307019
日期:2014.1.13
Triarylmethanes, which are valuable structures in materials, sensing and pharmaceuticals, have been synthesized starting from methylphenylsulfone as an inexpensive and readily available template. The three aryl groups were installed through two sequential palladium‐catalyzed CH arylation reactions, followed by an arylative desulfonation. This method provides a new synthetic approach to multisubstituted
Additive effects on palladium-catalyzed deprotonative-cross-coupling processes (DCCP) of sp<sup>3</sup>C–H bonds in diarylmethanes
作者:Ana Bellomo、Jiadi Zhang、Nisalak Trongsiriwat、Patrick J. Walsh
DOI:10.1039/c2sc21673f
日期:——
directing groups, however, are still limited. We describe herein a study on the use of additives in Pd-catalyzed deprotonative-cross-coupling processes (DCCP) of sp3 C–H bonds of diarylmethanes with aryl bromides at roomtemperature. These studies resulted in development of four new efficient Pd-catalyzed DCCP using additives that enabled the generation of a range of sterically and electronically diverse