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A conceptually new and synthetically valuable radical Smiles rearrangement reaction is reported under undivided electrolytic conditions. This protocol employs an entirely new strategy for the electrochemical radical Smiles rearrangement. Remarkably, an amidyl radical generated from the cleavage of the N-O bond under reductive electrolytic conditions plays a crucial role in this transformation. Various hydroxylamine derivatives bearing different substituents are suitable in this electrochemical transformation, furnishing the corresponding amides in up to 86% yield.

Phenolic, lignin-derived substrates have emerged as desirable biorenewable chemical feedstocks for coupling reactions. A radical-mediated conversion of phenol derivatives to anilines is reported, using unfunctionalized hydroxamic acids as the N-centered radical source. The applicability of this triethyl phosphite mediated O-atom transfer approach, which tolerates a range of steric and electronic demands to naturally occurring phenols and lignin models, has been demonstrated in this work to access the corresponding aniline derivatives.

We report on the use of visible light photoredox catalysis for the radical Smiles rearrangement of 2-aryloxybenzoic acids to obtain aryl salicylates. The method is free of noble metals and operationally simple and the reaction can be run under mild batch or flow conditions. Being a redox neutral process, no stoichiometric oxidants or reductants are needed.

We have developed a highly efficient aryl migration from an aryl ether to a carboxylic acid group through retro-Smiles rearrangement by visible-light photoredox catalysis at ambient temperature. Transition metals and a stoichiometric oxidant and base are avoided in the transformation. Inspired by the high efficiency of this transformation and the fundamental importance of C?O bond cleavage, we developed a novel approach to the C?O cleavage of a biaryl ether to form two phenolic compounds, as demonstrated by a one-pot, two-step gram-scale reaction under mild conditions. The aryl migration exhibits broad scope and can be applied to the synthesis of pharmaceutical compounds, such as guacetisal. Primary mechanistic studies indicate that the catalytic cycle occurs by a reductive quenching pathway.

Introduction: After using insecticides over many years, the resistance and environmental issues have become great challenges to crop protection. Modern agriculture calls for new insecticidal candidates. Phthalic diamide insecticide containing adjacent two amide group were favored for its new mode of action. Most chemical optimizations of phthalic diamide insecticide focused on amide groups. Modifications on phenyl part including fewer substituent types. Objective: The objective of this article was to investigate the insecticidal activities variation by alter the orientation and distance of two amide by replace the phenyl part with oxydibenzene and diphenyl-amine. Results: The target compounds were synthesized by using Cu/CuI catalyzed Ullmann coupling and sulfonyl-O-acryl mixed-anhydride as reactive intermediate. All target compounds were evaluated against armyworm (Mythimna sepatara). Two of synthetic compounds containing multifluoro-alkoxyl substituent showed mortality rate of 100% at 500 mg L-1. DFT-based Potential energy surface scanning showed that the relative energies of three conformations of insecticidal compounds were very similar Conclusion: We designed, synthesized and characterized seventeen novel compounds for the insecticidal candidates. Two of them were found to be insecticidal. A preliminary structure-activity relationship showed that the multifluoro-alkoxyl groups on the benzene were preferred. The compound d5 could be a lead compound for further research.

We report herein, a silver(i)-catalyzed Smiles rearrangement of 2-aryloxy- or 2-(arylthio)benzoic acids to provide aryl-2-hydroxybenzoate or aryl-2-mercaptobenzoate dimer, respectively, through 1,5-aryl migration from oxygen or sulfur to carboxylate oxygen. Mechanistically, the aryl ether moiety undergoes an intramolecular ipso attack by the carboxyl radical followed by a C-O or C-S bond cleavage. Aryl-2-mercaptobenzoates undergo oxidative dimerization through a thiol moiety in situ.

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Substituted 2-phenoxybenzoic acid derivatives were synthesised in high yield and in short reaction times using the Ullmann condensation of 2-chlorobenzoic acid with phenol derivatives under microwave irradiation in dry media.

Irradiation of 2- and 4-xanthone acetic acid in aqueous buffer (pH 7.4) leads to efficient (Φ = 0.67 and 0.64, respectively) photodecarboxylation to give the corresponding methyl products, consistent with an intermediate benzylic carbanion. Fluorescence a

An improved synthesis of 2-carboxy substituted diphenylethers using water as solvent can be achieved by ultrasound irradiation. A number of diphenylethers was prepared in good yields in a very short reaction time.

(Matrix Presented) The double ortholithiation and electrophilic quench of N,N,N′N′-tetraisopropylbiphenyl-2,2′-dicarboxamide 1 is diastereoselective, giving the chiral C2-symmetric atropisomers of the 3,3′-disubstituted products 3. These chiral

A series of substituted xanthones was synthesized in order to prove the hypothesis that electron-withdrawing substituents enhance the antimycobacterial activity of these compounds, which is described by means of a QSAR equation with 13C NMR che

The synthesis of 2-carboxy-diphenylethers from o-chloro-benzoic acid and phenols is reported using water as solvent and copper, cuprous iodide and pyridine as catalysts.

A series of new N-(9H-xanthen-9-yl)aminoalkanamide and N-(9H-thioxanthen-9-yl)aminoalkanamide derivatives was synthesized and evaluated as potential intercalators by measuring their DNA binding affinity. They were also tested for cytotoxic activity against L1210. The results suggest that the cytotoxicity of these molecules was not due to an intercalating mechanism.

The novel class of xanthenone-4-acetic acids represented by the general formula (I) STR1 where R1 represents up to two of the groups lower alkyl, halogen, CF3, CN, NO2, NH2, CH2 COOH, OR2,

The synthesis of a series of N-(2-chloroethyl)-N'-(9H-xanthen-9-yl)-N-nitrosoureas and N-(2-chloroethyl)-N'-(9H-thioxanthen-9-yl)-N-nitrosoureas is described. The title compounds were evaluated against NSCLCN6 L16 bronchial epidermoid carcinoma in vitro and some of them were found to be active. N-(2-chloroethyl)-N'-(2-methoxy-9H-xanthen-9-yl)-N-nitrosourea (8e) was active against leukemia P388 tumor system in mice.

Flash vacuum pyrolysis of the allyl esters 2 (X=O, S, CH2, CO) at 900°C (10-2 Torr) gives dibenzofurans, dibenzothiophenes, fluorenes, and fluorenones respectively as the major products. The mechanism involves the phenyl radical intermediates 1 which equilibrate by intramolecular hydrogen transfer via six-membered transition states, prior to cyclisation.

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