The inside cover picture illustrates the radical transformations of propargylic alcohols to construct a series of functionalized skeletons. In this review, these reactions can be divided into four ...parts based on the different mechanisms of radical formation, just like the archer shooting at a range in the picture, firing the same arrow in different ways may produce different results. Details can be found in the review by Xian‐Rong Song and co‐workers (M. Liang, H. Ma, X.‐R. Song, Q. Xiao, Adv. Synth. Catal. 2024, 366, 2659–2677; DOI: 10.1002/adsc.202400247)
Indole-based diversification is highly desired in the DNA-encoded chemical library construction. Herein, we present a general strategy for on-DNA synthesis of diverse C3-functionalized indole ...derivatives via indole π-activated alcohol formation followed by direct dehydrative coupling. Highly efficient bond linkages of C–C, C–N, and C–S were achieved to fuse building blocks that are widely commercially available. DNA-encoding compatibility of the method has been further demonstrated to pave an avenue for application in constructing indole-focused three-dimensional libraries.
Stable F-T-based catalyst development in direct CO hydrogenation to higher alcohols is still a challenge at present. In this study, CuFe/SiOsub.2 catalysts with a SiOsub.2 support treated with a ...piranha solution were prepared and evaluated in a long-term reaction. The treated catalyst showed higher total alcohols' selectivity and great stability during a reaction of more than 90 h. It was found that the treatment with the piranha solution enriched the surface hydroxyl groups on SiOsub.2, so that the Cu-Fe active components could be firmly anchored and highly dispersed on the support, resulting in stable catalytic performance. Furthermore, the in situ DRIFTS revealed that the adsorption strength of CO on Cusup.+ on the treated catalyst surface was weakened, which made the C-O bond less likely to be cleaved and thus significantly inhibited the formation of hydrocarbon products. Meanwhile, the non-dissociated CO species were obviously enriched on the Cusup.0 surface, promoting the formation of alcohol products, and thus the selectivity of total alcohols was increased. This strategy will shed light on the design of supported catalysts with stabilized structures for a wide range of catalytic reactions.
We report an efficient and selective methodology for the direct cross-coupling of alcohols with N-nucleophiles mediated by N-iodosuccinimide (NIS) as the non-metal, commercially available, low-cost, ...and most effective precatalyst among the N-halosuccinimides (NXSs) under mild reaction conditions enhancing the green chemical profiles of these reactions. The scale-up procedure was accomplished with almost quantitative yield, verifying the presented method's synthetic applicability and potential for industrial application.
Reactive alcohol functionality has been incorporated into a self-assembled M sub(2)L sub(3) mesocate. Post-synthetic modification of this complex with suitable isocyanates is not only possible, but ...is self-catalyzed by multiple internal hydrogen bonds from the self-assembly. As the metal-ligand coordination is reversible at elevated temperature, the isomeric distribution of product changes upon reaction, due to the different steric bulk conferred on the assembly after the modification.
The reduction of emissions from diesel engines has been studied by many authors and the modification of the fuel composition is one of the most discussed proposals. In this context, the study of ...abadiesel mixtures (Alcohol + Biodiesel + DIESEL) has attracted attention due to some of its characteristics, such as combustion heat similar to that of apurea diesel and reduction in the emission of particulate matter and toxic gases. The presence of the paraffinic compounds in diesel hampers the solubility of polar compounds, such as alcohols, for this reason biodiesel has been studied as an agent able to solubilize the alcohol in diesel and ensure the formulation of stable mixtures. The solubility of the systems of methanol + methylic soybean biodiesel + diesel and ethanol + ethylic soybean biodiesel + diesel was studied through the construction of liquid-liquid equilibrium curves for two temperatures and it was observed that increasing temperature always increases the solubility of the components. As expected, systems using ethanol show a large homogeneous region, when compared with methanol, due to higher solubility of ethanol in diesel. The knowledge of physicalachemical properties is essential for the formulation of a fuel with characteristics within specifications. For this reason, density and viscosity data were determined for the pure/pseudo-pure components and pseudo-binary and pseudo-ternary mixtures at several temperatures and compositions. Temperature and alcohol content of the blends of alcohol + biodiesel + diesel were recognized as a major factor governing physical stability. Nevertheless, flash point was mainly dominated by the concentration of alcohol.
Magnetic PdaCo bimetallic nanoparticles supported on reduced graphene oxide sheets (PdaCo/RGO) with excellent electrocatalytic performance have been synthesized by a rapid reducing method, using ...sodium hypophosphite as the reducing agent. The loading and crystalline phase of cobalt in the PdaCo/RGO hybrids varied as to the initial amount of cobalt salt and reducing agent. Transmission electron microscopy images show that the mean size of the PdaCo bimetallic nanoparticles was about 10a13 nm and without significant agglomeration. At the same Pd loading on graphene, the current densities of the forward anodic peak of the different PdaCo/RGO catalysts was decreased by about 25% when compared with that of the pure Pd nanoparticles supported on reduced graphene oxide for both methanol and ethanol oxidation. However, chronoamperometry tests confirmed that the stability was increased by up to 240% and 225% for methanol oxidation and ethanol oxidation, respectively. It is hypothesized that the Co layer on Pd partially blocks Pd sites sacrificing a small portion of the activity of the catalysts, but it leaves the remaining Pd more active and thus enhances alcohol oxidation kinetics and tolerance to poisoning intermediates. Catalytic performance of the PdaCo/RGO hybrids for alcohol oxidation is primarily affected by the interaction among Pd, Co, and graphene.
Azatitanacyclopropanes (titanaziridines) are shown to be stereochemically labile under reaction conditions for reductive cross-coupling. This fundamental property has been employed to realize highly ...selective asymmetric coupling reactions with allylic alcohols that proceed by dynamic kinetic resolution.
Objectives We posited mutually-reinforcing longitudinal pathways between occupation and alcohol use disorders (AUD). Method Longitudinal trajectories of work substantive complexity were constructed ...by growth mixture modelling (GMM) of occupational data from the National Longitudinal Survey of Youth 1979 and O*NET work variables. AUD was determined using a set of 25 questions that map onto 9 criteria for alcohol dependence. Prevalent AUD was one occurred at or before the first alcohol questionnanire in 1989; an incident AUD was a new case between 1989 and the 1994 survey. The association between work trajectories and AUD was modelled using Poisson regression in a generalised linear model adjusting for covariates. Results Lower work trajectories were associated with higher AUD prevalence (prevalence ratio 1.41; 95% confidence interval 1.04–1.91 for lowest versus highest class). Incident AUDs were associated with risk of a decline in work trajectory class in both high (OR=2.68; 95% CI 1.34–5.35) and low (OR=1.62 95% CI 1.01–2.60) initial classes. Interval educational attainment was not associated with AUD within a specific occupaitonal trajectory class Conclusions Low occupational trajectories are associated with increased AUD prevalence. Incident AUDs may be followed by a decline in work SC. These findings suggest self-reinforcing relations between the development of AUD and both prior and subsequent work.
In this study PtaTiO2 binary electrodes were prepared by means of thermal decomposition of chloride precursors on Ti substrates, characterised by X-ray Diffraction (XRD), Scanning Electron Microscopy ...(SEM), X-ray Photoelectron Spectroscopy (XPS), electrochemical techniques and CO stripping and used as anodes for alcohol oxidation. The minimization of the Pt loading without electrocatalytic activity losses was also explored. TiO2 was chosen due to its chemical stability, low cost and excellent properties as substrate for Pt dispersion. It was found that TiO2 loading up to 50% results in Electrochemically Active Surface (EAS) increase. The EAS of Pt(50%)-TiO2(50%) was found to be almost one order of magnitude higher than that of pure Pt while the EAS of samples with Pt loading lower than 30% was negligible. The above conclusion has been confirmed both by following the charge of the reduction peak of platinum oxide and by CO stripping experiments. All samples have been evaluated during the electrochemical oxidation of methanol and ethanol. In both cases the Pt(50%)-TiO2(50%) electrode had better electrocatalytic activity than the pure Pt anode. The observed higher performance of the binary electrodes was mainly attributed to the enhanced Pt dispersion as well as the formation of smaller Pt particles by the addition of TiO2.
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