Institut für Organische Chemie, Albert-Ludwigs-Universität Freiburg , Albertstrasse 21, 79104 Freiburg im Breisgau, Germany.
J Am Chem Soc. 2014 Jan 22;136(3):862-5. doi: 10.1021/ja411397g. Epub 2014 Jan 9.
A rhodium-catalyzed chemo- and regioselective intermolecular decarboxylative addition of β-ketoacids to terminal allenes is reported. Using a Rh(I)/DPPF system, tertiary and quaternary carbon centers were formed with exclusively branched selectivity under mild conditions. Preliminary mechanism studies support that the carbon-carbon bond formation precedes the decarboxylation and the reaction occurs in an outer-sphere mechanism.
报道了铑催化的β-酮酸与末端炔的化学选择性和区域选择性的脱羧加成反应。在温和条件下,使用 Rh(I)/DPPF 体系,仅以支链选择性形成了叔碳和季碳中心。初步的机理研究表明,碳-碳键的形成先于脱羧,反应在外层机制中进行。