We report an innovative approach for the selective synthesis of polyfunctional derivatives by cross-combination of different radicals generated under mild conditions. The coordinating effect of Ti(IV) plays a key role in the reaction mechanism: due to its chelating action on the hydroxyl groups, it promotes the homolytic C-C bond cleavage of R,β-dihydroxy ketones by enhancing the captodative effect and the consequent stabilization of the corresponding R-hydroxy-R-carbonyl radicals. When these radicals are generated in the presence of stoichiometric amounts of TiCl 4 and 2,2′-azo-bis-isobutyronitrile (AIBN) is employed as a source of R-cyanoisopropyl radicals, the selective radical-radical cross-coupling is observed, affording the corresponding β-hydroxynitriles in high yields. This innovative methodology allows application of the well-known Ingold-Fischer effect to a wider range of stabilized carbon-centered radicals, whose formation derives from the chelating action of Ti(IV).

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The times are changing: A batch process, the Minisci epoxidation, is transformed into a continuous‐flow protocol for the selective aerobic radical epoxidation of alkenes. The use of a novel reactor type allows to considerably shorten reactor residence times. Experimental results suggest that two different reaction mechanisms exist for the oxidation: one for the batch conditions and a different one for flow synthesis protocol.

A multivariate design and optimization study for the synthesis of the bromoalkanol 10-bromo-1-decanol using decane-1,10-diol as substrate is reported. The bromination process was supported by the phase transfer catalyst tetrabutylammonium bromide with aqueous HBr (48%) as the brominating reagent. The optimized batch protocol provided a yield of 64% of 10-bromo-1-decanol 2 TM with a conversion of 80%, and 10% of the dibrominated alkane 1,10dibromodecane 3, a characteristic byproduct, was formed.