C-H bond activation at cationic [(η-CMe)Ir(PMeAr')] centers is described, where PMeAr' are the terphenyl phosphine ligands PMeAr and PMeAr. Different pathways are defined for the conversion of the five-coordinate complexes [(η-CMe)IrCl(PMeAr')], 2(Xyl) and 2(Dipp), into the corresponding pseudoallyls 3(Xyl) and 3(Dipp). In the absence of an external Brønsted base, electrophilic, remote ζ C-H activation takes place, for which the participation of dicationic species, [(η-CMe)Ir(PMeAr')], is proposed. When NEt is present, the PMeAr system is shown to proceed via 4(Dipp) as an intermediate en route to the thermodynamic, isomeric product 3(Dipp). This complex interconversion involves a non-innocent CMe ligand, which participates in C-H and C-C bond formation and cleavage. Remarkably, the conversion of 4(Dipp) to 3(Dipp) also proceeds in the solid state.
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http://dx.doi.org/10.1021/jacs.8b11752 | DOI Listing |
Nat Commun
January 2025
Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai, PR China.
Allylic ethers and alcohols are essential structural motifs commonly present in natural products and pharmaceuticals. Direct allylic C-H oxygenation of internal alkenes is one of the most direct methods, bypassing the necessity for an allylic leaving group that is needed in the traditional Tsuji-Trost reaction. Herein, we develop an efficient and practical method for synthesizing (E)-allyl ethers from readily available internal alkenes and alcohols or phenols via selective allylic C-H oxidation.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
RIKEN: Rikagaku Kenkyujo, Center for Sustainable Resource Science, 2-1 Hirosawa, 351-0198, Wako, JAPAN.
Transition-metal-catalyzed selective and efficient activation of an inert C-H bond in an organic substrate is of importance for the development of streamlined synthetic methodologies. An attractive approach is the design of a metal catalyst capable of recognizing an organic substrate through noncovalent interactions to control reactivity and selectivity. We report here a spirobipyridine ligand that bears a hydroxy group that recognizes pyridine and quinoline substrates through hydrogen bonding, and in combination with an iridium catalyst enables site-selective C-H borylation.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
School of Advanced Materials Science and Engineering, Sungkyunkwan University, Suwon 16419, Republic of Korea.
Atomic layer deposition (ALD) of high-k dielectric films on MoS channels can lead to inadvertent remote electron doping of channels owing to nonequilibrium ALD conditions, such as the low temperatures and short purge times required for pinhole-free coating, as well as the weak physical adsorption of ALD precursors on MoS. In this study, we propose the application of a simple and effective HO vapor post-treatment (HO PT) at 100 °C immediately after complete integration of bottom- and top-gate monolayer MoS field-effect transistors (FETs), to address the inadvertent channel doping effect. When HO PT was applied to bottom-gate monolayer MoS FETs with an ALD-AlO passivation layer, the mitigation of channel doping was confirmed through electrical and optical measurements.
View Article and Find Full Text PDFChem Sci
January 2025
Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules, College of Chemistry and Chemical Engineering, Hubei University Wuhan 430062 P. R. China
The prevalence of naphthalene compounds in biologically active natural products, organic ligands and approved drugs has motivated investigators to develop efficient strategies for their selective synthesis. C-H functionalization of naphthalene has been frequently deployed, but mainly involves two-component reactions, while multiple-component C-H functionalization for the synthesis of naphthalene compounds has thus far proven elusive. Herein, we disclose a versatile three-component protocol for the modular synthesis of multifunctional naphthalenes from readily available simple naphthalenes, olefins and alkyl bromides P(iii)-assisted ruthenium-catalyzed remote C-H functionalization.
View Article and Find Full Text PDFJACC Adv
January 2025
Knight Cardiovascular Institute, Oregon Health and Science University, Portland, Oregon, USA.
Background: Patients with systemic right ventricle (SRV), either d-transposition of the great arteries following an atrial switch procedure or congenitally corrected transposition of the great arteries, develop severe right ventricular dysfunction, prompting appropriate medical therapy. However, the efficacy of beta-blockers and angiotensin receptor blockers or angiotensin-converting enzyme inhibitors (ACEI) in SRV patients is unproven.
Objectives: The objective of this study was to determine the effects of ACEI/ARB and beta-blockers on outcomes in SRV patients after accounting for likely cofounders affecting their use.
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