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Metal-free, Regio-, and Stereo-Controlled Hydrochlorination and Hydrobromination of Ynones and Ynamides.

ABSTRACT: We developed an atom-economical and metal-free method for the regio- and stereo-selective hydrohalogenation of ynones and ynamides using easy to handle DMPU/HX (X = Br or Cl) reagents. The reaction operates under mild conditions and a range of functional groups is well tolerated. We propose that the hydrohalogenation of ynones gives the anti-addition products via a concerted multimolecular AdE3 mechanism and that the hydrohalogenation of ynamides produces the syn-addition products via a cationic keteniminium intermediate.

SUBMITTER: Zeng X

PROVIDER: S-EPMC5735994 | biostudies-literature |

REPOSITORIES: biostudies-literature

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