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Abstract A three‐component coupling approach toward structurally complex dialkylsulfides is described via the nickel‐catalyzed 1,2‐carbosulfenylation of unactivated alkenes with organoboron nucleophiles and alkylsulfenamide (N−S) electrophiles. Efficient catalytic turnover is facilitated using a tailored N−S electrophile containing anN‐methyl methanesulfonamide leaving group, allowing catalyst loadings as low as 1 mol %. Regioselectivity is controlled by a collection of monodentate, weakly coordinating native directing groups, including sulfonamides, amides, sulfinamides, phosphoramides, and carbamates. Key to the development of this transformation is the identification of quinones as a family of hemilabile and redox‐active ligands that tune the steric and electronic properties of the metal throughout the catalytic cycle. Density functional theory (DFT) results show that the duroquinone (DQ) ligand adopts different coordination modes in different stages of the Ni‐catalyzed 1,2‐carbosulfenylation‐binding as an η⁶capping ligand to stabilize the precatalyst/resting state and prevent catalyst decomposition, binding as an X‐type redox‐active durosemiquinone radical anion to promote alkene migratory insertion with a less distorted square planar Ni(II) center, and binding as an L‐type ligand to promote N−S oxidative addition at a relatively more electron‐rich Ni(I) center. 

Electron-doped cuprates consistently exhibit strong antiferromagnetic correlations, leading to the prevalent belief that antiferromagnetic spin fluctuations mediate Cooper pairing in these unconventional superconductors. However, early investigations showed that although antiferromagnetic spin fluctuations create the largest pseudogap at hot spots in momentum space, the superconducting gap is also maximized at these locations. This presented a paradox for spin-fluctuation-mediated pairing: Cooper pairing is strongest at momenta where the normal-state low-energy spectral weight is most suppressed. Here we investigate this paradox and find evidence that a gossamer—meaning very faint—Fermi surface can provide an explanation for these observations. We study Nd2–xCexCuO4 using angle-resolved photoemission spectroscopy and directly observe the Bogoliubov quasiparticles. First, we resolve the previously observed reconstructed main band and the states gapped by the antiferromagnetic pseudogap around the hot spots. Within the antiferromagnetic pseudogap, we also observe gossamer states with distinct dispersion, from which coherence peaks of Bogoliubov quasiparticles emerge below the superconducting critical temperature. Moreover, the direct observation of a Bogoliubov quasiparticle permits an accurate determination of the superconducting gap, yielding a maximum value an order of magnitude smaller than the pseudogap, establishing the distinct nature of these two gaps. We propose that orientation fluctuations in the antiferromagnetic order parameter are responsible for the gossamer states. 

We report a regioselective, nickel-catalyzed syn-1,2-carbosulfenylation of non-conjugated alkenyl carbonyl compounds with alkyl/arylzinc nucleophiles and tailored N–S electrophiles. This method allows the simultaneous installation of a variety of C(sp3) and S(Ar) (or Se(Ar)) groups on to unactivated alkenes, which complements previously developed 1,2-carbosulfenylation methodology in which only C(sp2) nucleophiles are compatible. A bidentate directing auxiliary controls regioselectivity, promotes high syn-stereoselectivity with a variety of E- and Z- internal alkenes, and enables the use of a variety of electrophilic sulfenyl (and seleno) electrophiles. Among compatible electrophiles, those with N-alkyl-benzamide leaving groups were found to be especially effective, as determined through comprehensive structure–reactivity mapping. 

Abstract Recent experiments observed significant energy transfer in type-II van der Waals (vdW) heterostructures, such as WS 2 /MoSe 2 , which is surprising due to their staggered band alignment and weak spectral overlap. In this work, we carry out first-principles calculations to shed light on energy and charge transfer in WS 2 /MoSe 2 heterostructure. Incorporating excitonic effect in nonadiabatic electronic dynamics, our first-principles calculations uncover a two-step process in competing energy and charge transfer, unravel their relative efficiencies and explore the means to control their competition. While both Dexter and Förster mechanisms can be responsible for energy transfer, they are shown to operate at different conditions. The excitonic effect is revealed to drive ultrafast energy and charge transfer in type-II WS 2 /MoSe 2 heterostructure. Our work provides a comprehensive picture of exciton dynamics in vdW heterostructures and paves the way for rational design of novel vdW heterostructures for optoelectronic and photovoltaic applications.