A unique Markovnikov hydroalkoxylation of unactivated olefins with a cobalt complex, silane, and N-fluoropyridinium salt is reported. Further optimization of reaction conditions yielded high functional group tolerance and versatility of alcoholic solvent employed, including methanol, i-propanol, and t-butanol. Use of trifluorotoluene as a solvent made the use of alcohol in stoichiometric amount possible. Mechanistic insight into this novel catalytic system is also discussed. Experimental results suggest that catalysis involves both carbon radical and carbocation intermediates.

Functional group tolerance is one of the important requirements for chemical reactions, especially for the synthesis of complex molecules. Herein, we report a mild, general, and functional group tolerant intramolecular hydroamination of unactivated olefins using a Co(salen) complex, an N-fluoropyridinium salt, and a disiloxane reagent. This method, which was carried out at room temperature (or 0 °C), afforded three-, five-, six-, and seven-membered ring nitrogen-containing heterocyclic compounds and was compatible with diverse functional groups.

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Synthesis. -(SHIGEHISA*, H.; KOSEKI, N.; SHIMIZU, N.; FUJISAWA, M.; NIITSU, M.; HIROYA, K.; J. Am. Chem. Soc. 136 (2014) 39, 13534-13537, http://dx.doi.org/10.1021/ja507295u ; Fac. Pharm., Musashino Univ., Nishitokyo, Tokyo 202, Japan; Eng.) -H. Hoennerscheid