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Direct, redox-neutral prenylation and geranylation of secondary carbinol C-H bonds: C4-regioselectivity in ruthenium-catalyzed C-C couplings of dienes to ?-hydroxy esters.

ABSTRACT: The ruthenium catalyst generated in situ from Ru(3)(CO)(12) and tricyclohexylphosphine, PCy(3), promotes the redox-neutral C-C coupling of aryl-substituted ?-hydroxy esters to isoprene and myrcene at the diene C4-position, resulting in direct carbinol C-H prenylation and geranylation, respectively. This process enables direct conversion of secondary to tertiary alcohols in the absence of stoichiometric byproducts or premetalated reagents, and is the first example of C4-regioselectivity in catalytic C-C couplings of 2-substituted dienes to carbonyl partners. Mechanistic studies corroborate a catalytic cycle involving diene-carbonyl oxidative coupling.

SUBMITTER: Leung JC

PROVIDER: S-EPMC3459341 | biostudies-literature | 2012 Sep

REPOSITORIES: biostudies-literature

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Direct, redox-neutral prenylation and geranylation of secondary carbinol C-H bonds: C4-regioselectivity in ruthenium-catalyzed C-C couplings of dienes to α-hydroxy esters.

Leung Joyce C JC Geary Laina M LM Chen Te-Yu TY Zbieg Jason R JR Krische Michael J MJ

Journal of the American Chemical Society 20120917 38

The ruthenium catalyst generated in situ from Ru(3)(CO)(12) and tricyclohexylphosphine, PCy(3), promotes the redox-neutral C-C coupling of aryl-substituted α-hydroxy esters to isoprene and myrcene at the diene C4-position, resulting in direct carbinol C-H prenylation and geranylation, respectively. This process enables direct conversion of secondary to tertiary alcohols in the absence of stoichiometric byproducts or premetalated reagents, and is the first example of C4-regioselectivity in cataly ...[more]

PMID: 22985393

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