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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 | 2017 Dec

REPOSITORIES: biostudies-literature

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

Zeng Xiaojun X Lu Zhichao Z Liu Shiwen S Hammond Gerald B GB Xu Bo B

The Journal of organic chemistry 20171207 24

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 Ad<sub>E</sub>3 mechanism and that the hydrohalogenation of ynamides produces the syn-addition products via ...[more]

PMID: 29166765

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