Non-symmetrical bromoiodanes are useful for bromination reactions, and some protocols were found to be suitable for specific substrates. Herein, we report the use of a DIB/BBr
protocol for various ...bromination reactions, including electrophilic bromination of arenes, carbonyl C-H monobromination, bromolactonization, bromocarbocyclization, intermolecular bromoetherification of olefin, and light-triggered C(sp
)-H bromination.
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IJS, KILJ, NUK, PNG, UL, UM
Stable cyclopalladated complexes containing an (sp3)C–Pd bond were synthesized via α-CH2 deprotonation and palladation of N-alkyl groups of carbene ligands bearing electron-withdrawing substituents. ...The strong electron donating strengths of the resulting CNHC^Csp3 chelators were experimentally identified, and the palladacycle underwent template-directed, versatile C-halogenation with X2.
PhIBr
, first purported to exist over 100 years ago, has been subject of few reports due to its low stability. However, a recent publication proposes a reaction of PIFA (PhI(OC(O)-CF
)
) with TMSBr ...to form PhIBr
and demonstrated its efficacy in aryl brominations. This report investigates this synthesis by replicating bromination reactions claiming to use
PhIBr
as described. The spectroscopical and computational results indicate formation of PhI and Br
where Br
is responsible for bromination and no supporting evidence for invoking PhIBr
as an intermediate is found.
F-fluorination is an important and growing field in organic synthesis that has attracted many chemists in the recent past. Here we present our own, biased perspective with a focus on our own ...chemistry that evaluates recent advances in the field and provides our opinion on the challenges for the development of new chemistry, so that it may have an impact on imaging. We hope that the manuscript will provide a useful guide to chemists to develop reliable and robust reaction chemistry suitable for radiofluorination to have a real impact on human health.
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IJS, KILJ, NUK, PNG, UL, UM
We report, herein, a photoinduced iron-catalyzed direct chlorination of aromatic sulfonyl chloride at room temperature. In this protocol, FeCl
-catalyzed direct chlorination has been realized at room ...temperature under the irradiation of light (400-410 nm). During the process, many commercially or readily available substituted aromatic sulfonyl chlorides could produce the corresponding aromatic chlorides in moderate to good yields.
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IJS, KILJ, NUK, PNG, UL, UM
Solar‐energy‐driven CO2 conversion into value‐added chemical fuels holds great potential in renewable energy generation. However, the rapid recombination of charge carriers and deficient reactive ...sites, as two major obstacles, severely hampers the photocatalytic CO2 reduction activity. Herein, a desirable surface halogenation strategy to address the aforementioned concerns over a Sillén‐related layer‐structured photocatalyst Bi2O2(OH)(NO3) (BON) is demonstrated. The surface halogen ions that are anchored on the Bi atoms by replacing surface hydroxyls on the one hand facilitate the local charge separation, and, on the other hand, activate the hydroxyls that profoundly boost the adsorption of CO2 molecules and protons and facilitate the CO2 conversion process, as evidenced by experimental and theoretical results collectively. Among the three series of BON‐X (X = Cl, Br, and I) catalysts, BON‐Br shows the most substantially enhanced CO production rate (8.12 µmol g−1 h−1) without any sacrificial agents or cocatalysts, ≈73 times higher than that of pristine Bi2O2(OH)(NO3), also exceeding that of the state‐of‐the‐art photocatalysts reported to date. This work presents a surface polarization protocol for engineering charge behavior and reactive sites to promote photocatalysis, which shows great promise to the future design of high‐performance materials for clean energy production.
Surface‐halogenation‐induced atomic site activation and local charge separation of layered Bi2O2(OH)(NO3) is presented. Br−‐modified Bi2O2(OH)(NO3) shows the most prominent CO2 activation activity with a CO production rate of 8.12 µmol g−1 h−1, which is 73 times higher than that of bulk Bi2O2(OH)(NO3), exceeding that of most previously reported state‐of‐the‐art photocatalysts.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
A mild, versatile, and convenient method for the efficient oxytrifluoromethylation of unactivated alkenes based on a copper-catalyzed oxidative difunctionalization strategy has been developed. This ...methodology provides access to a variety of classes of synthetically useful CF3-containing building blocks from simple starting materials.
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IJS, KILJ, NUK, PNG, UL, UM
Because of the electron-rich property of indoles, direct functionalization strategies towards indoles generally involve electrophilic substitutions. In this paper, an efficient protocol for ...nucleophilic hydroxylation, halogenation and esterification of indoles
via
the aromatic Pummerer process was developed. With the advantages of readily accessible starting materials, simple operation and mild conditions, this protocol should be of interest to synthetic scientists.
Because of the electron-rich property of indoles, direct functionalization strategies towards indoles generally involve electrophilic substitutions.
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