In recent years, two-dimensional (2D) black phosphorus (BP) has been widely applied in many fields, such as (opto)electronics, transistors, catalysis and biomedical applications due to its large surface area, tunable...
A novel radical phosphinylation of α,α-diaryl allylic alcohols with arylphosphine oxides was described for the direct preparation of α-aryl-β-phosphinylated carbonyl ketones in medium to good yields via 1,2-aryl migration. In this reaction, formation of new C(Ar)-C(sp(3)) and C(sp(3))-P bonds was observed.
Photothermally
assisted superhydrophobic sponges play a vital role
in the fields of waste oil collection, oil purification, and solar
desalination. However, the widely reported superhydrophobic sponges
with photothermal efficiency usually suffer from a post-/premodification
process of harmful materials, high loading content of photothermal
agents, and low photothermal efficiency. Herein, an MXene-based melamine
sponge (MS) was facilely fabricated by hydrogen bonding interaction
between the amino groups on the skeleton of the MS and the polar groups
on the surface of the as-exfoliated 2D MXene Ti3C2T
x
nanosheets. Interestingly, the as-fabricated
MXene sponge exhibits excellent hydrophobicity and high photothermal
efficiency under an extremely low loading of MXene Ti3C2T
x
nanosheets (0.1 wt %). Moreover,
the highly hydrophobic sponge also possesses a high oil absorption
capacity as high as 176 times of its own weight and keeps stable under
multiple absorption/desorption cycling tests. Surprisingly, the surface
temperature of the MXene sponge can quickly reach 47 °C under
illumination and has good reproducibility during multiple light on/off
cycles. The excellent photothermal performance and large oil absorption
capacity of the MXene sponge endow the highly hydrophobic sponge with
fast solvent evaporation speed and high-purity waste oil collection
(99.7 wt % dichloromethane) under illumination, which holds great
promise for oil/water separation, leaked oil collection, and photo-driven
waste oil collection and purification applications. It is envisioned
that this work can open a new strategy for new designs of 3D multifunctional
sponges for high-performance waste oil collection and purification.
Ynones and ynoates react with pinacolborane in a divergent manner in the presence of nucleophilic phosphine catalysts. Ynones are transformed to the corresponding propargyl alcohols in good yields with high regio- and chemoselectivity. Ynoates undergo highly regio- and stereoselective trans-hydroboration to produce E-vinylboronates. Impressive divergence in reactivity of ynones and ynoates can be traced back to the mechanistic aspects of 1,2-reduction and trans-hydroboration. A comparative analysis of the two pathways paints a complex picture in which different reaction rates control selectivity in these seemingly unrelated processes and explains how sufficiently acidic protons in the reaction mixtures can be used to steer the selectivity in different directions.
Latent nucleophiles are compounds that are themselves not nucleophilic but can produce a strong nucleophile when activated. Such nucleophiles can expand the scope of Lewis base catalyzed reactions. As a proof of concept, we report that N‐silyl pyrroles, indoles, and carbazoles serve as latent N‐centered nucleophiles in substitution reactions of allylic fluorides catalyzed by Lewis bases. The reactions feature broad scopes for both reaction partners, excellent regioselectivities, and produce enantioenriched N‐allyl pyrroles, indoles, and carbazoles when chiral cinchona alkaloid catalysts are used.
A metal-free method for direct C(sp(3))-H bond functionalization of simple ethers with α,α-diaryl allylic alcohols is described. The established protocol provides facile access to α-aryl-β-oxyalkylated carbonyl ketones via radical addition and a 1,2-aryl migration cascade process. An application of the product has been demonstrated in the synthesis of a serotonin antagonist.
An efficient I2 (20 mol %)/TBPB mediated oxidative formal [4 + 1] cycloaddition of N-tosylhydrazones with anilines via C-N/N-N bond formation and S-N cleavage has been developed. This protocol represents a simple, general, and efficient approach for the construction of 1,2,3-triazoles under metal-free and azide-free conditions by utilizing a catalytic amount of I2.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.