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Efficient alkyl ether synthesis via palladium-catalyzed, picolinamide-directed alkoxylation of unactivated C(sp3)-H and C(sp2)-H bonds at remote positions. | LitMetric

We report the efficient synthesis of alkyl ethers by the functionalization of unactivated sp(3)- and sp(2)-hybridized C-H bonds. In the Pd(OAc)(2)-catalyzed, PhI(OAc)(2)-mediated reaction system, picolinamide-protected amine substrates undergo facile alkoxylation at the γ or δ positions with a range of alcohols, including t-BuOH, to give alkoxylated products. This method features a relatively broad substrate scope for amines and alcohols, inexpensive reagents, and convenient operating conditions. This method highlights the emerging value of unactivated C-H bonds, particularly the C(sp(3))-H bond of methyl groups, as functional groups in organic synthesis.

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http://dx.doi.org/10.1021/ja3023972DOI Listing

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