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Geminal cross couplings using multiple components enable the formation of several different bonds at one site in the building of tertiary and quaternary alkanes. Nevertheless, there are remaining issues of concern—cleavage of two geminal bonds and control of selectivity present challenges. We report here the geminal cross couplings of three components by reactions of dihaloalkanes with organomagnesium and chlorosilanes or alkyl tosylates by Cr catalysis, affording the formation of geminal C−C/C−Si or C−C/C−C bonds in the creation of tertiary and quaternary alkanes. The geminal couplings are catalyzed by low‐cost CrCl2, enabling the sluggishness of competitive Kumada‐type side couplings and homocouplings of Grignard reagents, in achieving high chemoselectivity. Experimental and theoretical studies indicate that two geminal C‐halide bonds are continuously cleaved by Cr to afford a metal carbene intermediate, which couples with a Grignard reagent, followed by silylation, in the formation of geminal C−C and C−Si bonds via a novel inner‐sphere radical coupling mechanism. These three‐component geminal cross couplings are value‐addition to the synthesis of commercial drugs and bioactive molecules in medicinal chemistry. [ABSTRACT FROM AUTHOR]

Purpose: To assess rural‐urban differences in participation rates of diabetes self‐management education and associated factors among Medicare beneficiaries with type 2 diabetes (T2DM). Methods: Data were from the 2016 to 2018 Medicare Current Beneficiary Survey (MCBS). Participation in diabetes self‐management education was self‐reported. The study sample included 3,799 beneficiaries aged 65 years and older with self‐reported T2DM. Logistic regression was used to assess the association of participation in diabetes self‐management education and residential location. Sampling weights embedded in the MCBS were incorporated into all analyses. Findings: Overall, the participation rate of diabetes self‐management education was 46.8% (95% CI: 44.4%‐49.2%). The rate was 40.3% for beneficiaries in rural areas, 48.0% for suburban areas, and 47.3% for urban areas. About 31% of beneficiaries newly diagnosed with diabetes did not participate within the past year. Controlling for other covariates, beneficiaries in rural areas were less likely to have participated in diabetes self‐management education (AOR = 0.73, 95% CI: 0.55‐0.95) than those living in urban areas. Asian Americans were less likely to have participated (AOR = 0.49, 95% CI: 0.28‐0.84) than Whites. Those who were older, with lower education, and lower income levels were less likely to have participated (P <.05). Conclusions: Recent MCBS data indicate that more than half of Medicare beneficiaries with T2DM did not participate in diabetes self‐management education, and the participation rate in rural areas was 7 percentage points lower than that ​in urban areas. The study findings highlight challenges to maximize the benefits of participating in diabetes self‐management education, particularly in rural areas. [ABSTRACT FROM AUTHOR]

Binders are required to dissipate huge mechanical stress and enhance the lithium‐ion diffusion kinetics of silicon anodes during cycling. Herein, a stress‐distribution binder with high ionic conductivity (GG‐g‐PAM) is constructed by grating polyacrylamide (PAM) onto ion‐conductive guar gum (GG) backbone. The mechanical stress distribution toward the grafted PAM chain enables the effective stress dissipation of the GG‐g‐PAM binder, and thus maintains a stable electrode‐electrolyte interface during cycling. The stress dissipation ability of the GG‐g‐PAM binder is confirmed by PeakForce atomic force microscopy experiments and finite element simulations. In addition, lithium complexation sites provided by oxygen heteroatoms in GG of the GG‐g‐PAM binder construct the Li‐ion pathways for facilitating Li ionic diffusion in the Si anodes. The good cyclabilities of Ah‐level pouch cells based on Si nanoparticle anodes strongly confirm GG‐g‐PAM as a desirable binder for practical Si anodes. [ABSTRACT FROM AUTHOR]

Reported here is a straightforward process in which a cyclic (alkyl)(amino)carbene/Rh catalyst system facilitates the preferential addition of hydrogen to the substitution sites of difluoromethylated and trifluoromethylated arenes and heteroarenes, leading to dearomative reduction. This strategy enables the diastereoselective synthesis of cis‐difluoromethylated and cis‐trifluoromethylated cycloalkanes and saturated heterocycles, and even allows formation of all‐cis multi‐trifluoromethylated cyclic products with a defined equatorial orientation of the di‐ and trifluoromethyl groups. Deuterium‐labeling studies indicate that hydrogen preferentially attacks the substitution sites of planar arenes, resulting in dearomatization, possibly with heterogeneous Rh as the reactive species, followed by either reversible or irreversible hydrogen addition to the nonsubstitution sites. [ABSTRACT FROM AUTHOR]

A mild, scalable, high yielding, and rapid route to access diverse nitriles from aldehyde oxime esters enabled by iron(III) and phenol co‐catalysis has been developed. The reaction was performed at room temperature to give nitriles in excellent yield within minutes. Mechanistic studies show that the reaction may proceed through a radical process in which benzoyl aldehyde oxime is not only a substrate, but also an ancillary ligand to support iron salt in the promotion of the transformation. [ABSTRACT FROM AUTHOR]

We herein report the hydrogenation of substituted aryl‐ and heteroaryl boronate esters for the selective synthesis of cis‐substituted borylated cycloalkanes and saturated heterocycles. A cyclic (alkyl)(amino)carbene‐ligated rhodium complex with two dimethyl groups at the ortho‐alkyl scaffold of the carbene showed high reactivity in promoting the hydrogenation, thereby enabling the hydrogenation of (hetero)arenes with retention of the synthetically valuable boronate group. This process constitutes a clean, atom‐economic, as well as chemo‐ and stereoselective route for the generation of cis‐configured, diversely substituted borylated cycloalkanes and saturated heterocycles that are usually elusive and difficult to prepare. [ABSTRACT FROM AUTHOR]

A method for the ruthenium-catalyzed ortho-alkynylation of benzoic acids was developed. The reaction was found to be directed by a weakly coordinating carboxyl group and offers a facile route for the synthesis of ortho-alkynylated derivatives. A rare example of a bis(alkynylation) reaction of C-H bonds was described. [ABSTRACT FROM AUTHOR]

Reprogramming of somatic cells to induced pluripotent stem cells rewrites the code of cell fate at the chromatin level. Yet, little is known about this process physically. Here, we describe a fluorescence recovery after photobleaching method to assess the dynamics of heterochromatin/euchromatin and show significant heterochromatin loosening at the initial stage of reprogramming. We identify growth arrest and DNA damage-inducible protein a (Gadd45a) as a chromatin relaxer in mouse embryonic fibroblasts, which also enhances somatic cell reprogramming efficiency. We show that residue glycine 39 (G39) in Gadd45a is essential for interacting with core histones, opening chromatin and enhancing reprogramming. We further demonstrate that Gadd45a destabilizes histone- DNA interactions and facilitates the binding of Yamanaka factors to their targets for activation. Our study provides a method to screen factors that impact on chromatin structure in live cells, and identifies Gadd45a as a chromatin relaxer. [ABSTRACT FROM AUTHOR]

A fluoride-anion-induced, regioselective ring expansion of benzocyclic ketones and α-aryl cycloketones has been developed via insertion of arynes into unactivated benzylic C−C bonds. This reaction provides a straightforward, transition-metal-free avenue to prepare medium ring-fused benzocarbocycles by creating 'noble' seven-, eight-, and nine-membered rings. Applications of this method in the creation of medium-sized exocyclic and inner benzocyclic olefins, nine-membered lactones, and lactams are described. [ABSTRACT FROM AUTHOR]

Cyclic (amino)(aryl)carbenes (CAArCs) result from the replacement of the alkyl substituent of cyclic (alkyl)- (amino) carbenes (CAACs) by an aryl group. This structural modification leads to enhanced electrophilicity of the carbene center with retention of the high nucleophilicity of CAACs, and therefore CAArCs feature a small singlet-triplet gap. The isoindolium precursors are readily prepared in good yields, and deprotonation at low temperature, in the presence of [RhCl(cod)]2 and [(Me2S)AuCl] lead to air-stable rhodium and gold CAArC-supported complexes, respectively. The rhodium complexes promote the [3+2] cycloaddition of diphenylcyclopropenone with ethyl phenylpropiolate, and induce the addition of 2-vinylpyridine to alkenes by CH activation. The gold complexes allow for the catalytic threecomponent preparation of 1,2-dihydroquinolines from aniline and phenyl acetylene. These preliminary results illustrate the potential of CAArC ligands in transition-metal catalysis. [ABSTRACT FROM AUTHOR]

Review: [24 refs. [ABSTRACT FROM AUTHOR]

Review: 53 refs. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "Iron-Catalyzed, Chelation-Induced Remote C?H Allylation of Quinolines via 8-Amido Assistance" by Xuefeng Cong and Xiaoming Zeng, published in "Organic Letters" in 2014.

A simple procedure is developed to synthesize benzo[b][1,4]diazepines from o-phenylenediamine derivatives and terminal alkynes using a Au(I)-NHC-complex-catalyzed hydroamination/cyclization process. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "Aminocyanation by the Addition of N—CN Bonds to Arynes: Chemoselective Synthesis of 1,2-Bifunctional Aminobenzonitriles" by B. Rao and colleagues, published in the "Organic Letters" in 2014.

Review: 456 refs. [ABSTRACT FROM AUTHOR]