Oxidation of primary aliphatic aldehydes with p-trifluoromethylphenyl(difluoro)-λ(3)-bromane in dichloromethane at 0 °C afforded acid fluorides selectively in good yields, while that of aromatic aldehydes in chloroform at room temperature produced aryl difluoromethyl ethers. A larger migratory aptitude of aryl groups compared to primary alkyl groups during a 1,2-shift from carbon to an electron-deficient oxygen atom in bromane(III) Criegee-type intermediates will result in these differences in the reaction courses.
Hypervalent N-triflylimino-λ(3)-bromane undergoes direct and regioselective α-C-H amination of ethers at room temperature under transition metal-free conditions. Kinetic results, substituent and deuterium isotope effects suggest an asynchronous concerted organonitrenoid transition state with some hydride transfer character, analogous to that for alkane C-H insertions.
Ligand exchange of p-CF(3)C(6)H(4)BrF(2) with acetoxy groups using AcOH and Ac(2)O affords (diacetoxybromo)benzene in a high yield, which undergoes aziridination of alkenes in the presence of TfNH(2) and sulfamate esters in one pot under mild conditions. The aziridination with TfNH(2) proceeds stereospecifically with retention of stereochemistry of olefins at room temperature using limiting amounts of olefins under transition-metal-free conditions. The one-pot aziridination procedure using sulfamate esters can be applied to the intramolecular versions.
Reduction of cis-N-triflylaziridines with 10 equiv of Red-Al in toluene at -40 to 0 °C selectively afforded corresponding deprotected parent aziridines in good to high yields. N,N-Dialkyltriflylamides were also successfully cleaved under similar reaction conditions.
Eight indophenines were synthesized for the interest of studying biological activity especially for cytotoxicity. The cytotoxicity of some indophenines and some isatin derivatives was studied by the brine shrimp lethality bioassay. It was observed that all the indophenines from thiophene, thiazol and isatin derivatives showed potential cytotoxicity against brine shrimp nauplii and the structure activity relationships (SAR) of these compounds have been reported.
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