A new versatile method has been developed for the electrochemically assisted grafting of carbon materials. The approach is based on the reduction of iodonium salts and allows the immobilization not only of aryl groups, such as phenyl or nitrophenyl, but also of alkynyl groups under mild conditions. In particular, the immobilization of alkynyl groups is important because such grafting cannot be accomplished using any other known reductive procedure. The electrochemical properties of the grafted surfaces with estimated coverages of (4-6) x 10(-)(10) mol cm(-)(2) are investigated against the ferrocene and Fe(CN)(6)(3)(-) solution probes. The analysis of the surfaces is carried out by means of cyclic voltammetry and X-ray photoelectron spectroscopy.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1021/la050933e | DOI Listing |
J Org Chem
January 2025
Antibiotics Research and Re-evaluation Key Laboratory of Sichuan Province, Sichuan Industrial Institute of Antibiotics, School of Pharmacy, Chengdu University, 2025 Chengluo Avenue, Chengdu 610016, P. R. China.
We report a highly regioselective 1,2-addition of P(O)-H compounds to the in situ generated β,γ-alkynyl-α-ketimine derived from 3-alkynyl-3-hydroxyisoindolinones, which provided a general protocol for the preparation of 3,3-disubstituted isoindolinones featuring both phosphoryl and alkynyl groups at a quaternary carbon center. The use of only 2-5 mol % of an inexpensive catalyst (In(ClO)·8HO or Bi(OTf)) allowed the smooth output of the desired products under mild conditions (25 °C, 0.5-24 h) with a broad substrate scope (35 examples) in up to >99% yield.
View Article and Find Full Text PDFJ Org Chem
January 2025
School of Chemistry & Materials Science, Jiangsu Normal University, Xuzhou 221116, China.
1-Isochromene scaffolds are ubiquitous in natural products and significant bioactive molecules. Although several methods for these molecular syntheses have been developed, reports on the efficient construction of iminated isochromenes are still rather limited. Herein, we report a new Cu(II)-catalyzed annulation and sulfonylimination cascade of α-carbonyl-γ-alkynyl sulfoxonium ylides with sulfamides, enabling direct C-C σ-bond elimination to furnish iminated ()-1-isochromenes in 51-97% yields.
View Article and Find Full Text PDFAsian J Org Chem
January 2025
Department of Medicinal Chemistry, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, 160 Frelinghuysen Road, Piscataway, New Jersey 08854, USA.
A one-pot process was developed to synthesize in moderate to high yield a series of 2-substituted indoles and 7-azaindoles starting from 2-iodo--mesylarylamines and terminal alkynes in the presence of CuO in DMF at 90-120 °C. Without isolation of any intermediate, our optimized conditions enabled the introduction of ester, phenyl, hydroxymethyl, hydroxyethyl, -Boc-aminomethyl, and methyl at the 2-postion of indoles and 7-azaindoles. The reaction tolerates a variety of substrates containing halogens, or acid- or base-sensitive functional groups without requiring a Pd catalyst, a ligand, or a base.
View Article and Find Full Text PDFOrganometallics
January 2025
Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, U.K.
The group 1 alumanyls, [{SiN}AlM] (M = K, Rb, Cs; SiN = {CHSiMeNDipp}), display a variable kinetic facility (K < Rb < Cs) toward oxidative addition of the acidic C-H bond of terminal alkynes to provide the corresponding alkali metal hydrido(alkynyl)aluminate derivatives. Theoretical analysis of the formation of these compounds through density functional theory (DFT) calculations implies that the experimentally observed changes in reaction rate are a consequence of the variable stability of the [{SiN}AlM] dimers, the integrity of which reflects the ability of M to maintain the polyhapto group 1-arene interactions necessary for dimer propagation. These observations highlight that such "on-dimer" reactivity takes place sequentially and also that the ability of each constituent Al(I) center to effect the activation of the organic substrate is kinetically differentiated.
View Article and Find Full Text PDFJ Org Chem
January 2025
Key Laboratory of Functional Molecular Engineering of Guangdong Province, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, China.
Pd-catalyzed C4-selective alkynylation of indoles was established by employing glycine as a transient directing group. This reaction exhibits high regioselectivity with the tolerance of a wide scope of functional groups to afford diverse alkynylated indoles in moderate to good yields. Moreover, the readily accessible scale-up synthesis and further decorations to achieve multifunctionalized indoles demonstrate the synthetic potential of this protocol.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!