Asian Journal of Organic Chemistry

Not so scand-alous: We report a scandium(III) triflate catalyzed intramolecular Friedel–Crafts alkylation for the synthesis of 3-hydroxy-2-oxindoles. In comparison with nucleophilic conjugate additions of organometallic or electron-rich reagents to isatins and intramolecular addition of aryl chlorides to ketoamides, this protocol is simple, produces less waste, and omits organometallic reagents and halogenations. Bn=benzyl; DME=1,2-dimethoxyethane.

TiCl-ing your fancy: A simple and highly efficient synthetic method for the preparation of indolizines from the reaction of 2-enoylpyridines with sulfonamides in the presence of TiCl₄ under mild conditions has been developed. A subsequent phosphine-catalyzed aza-Michael reaction of the corresponding indolizines with vinyl ketones and activated allenes was also developed, which affords highly functionalized indolizines in excellent yields under mild conditions.

Betti you can: An efficient, sustainable, and a catalyst-free procedure for the synthesis of Betti bases by a one-pot, three-component, Mannich-type condensation of secondary amines, aldehydes, and β-naphthol in polyethylene glycol at room temperature has been developed. The products do not require purification by chromatography and the solvent was remarkably recyclable for up to four runs.

Not such a pushover: The properties of 15 D-π-A chromophores that feature ferrocene donors and NO₂ acceptors were investigated by X-ray analysis, electrochemistry, absorption spectroscopy, and DFT calculations. Systematic replacement of 1,4-phenylene with 2,5-thienylene π-linker subunits considerably affects the electronic properties of the push-pull chromophores. Thiophene proved to be a polarizable moiety that allows substantial intramolecular charge transfer.

PBI Friday: Functional perylene bisimide assemblies that are constructed based on complementary multiple hydrogen-bonding interactions are reviewed. Supramolecular engineering of well-defined, hydrogen-bonded oligomers or polymers results in the formation of predictable extended assemblies through π–π stacking interactions. The unique optoelectronic and stimuli-responsive properties as well as the various morphologies of such assemblies are also introduced.