Synthesis 2025; 57(01): 71-83
DOI: 10.1055/a-2353-1722
psp
Special Topic Dedicated to Prof. H. Ila

Magnesium-Mediated Regioselective Additions of Bromoform to Quinone Methides and Aurone-Derived Azadienes

Deepak Kumar
,
Nishikant Satam
,
I.N.N.N. thanks Science and Engineering Research Board (SERB), India for funding. D. K. Thanks CSIR India and N. S. thanks UGC India for a research fellowship.


Abstract

The magnesium-mediated addition of bromoform to conjugated electron-deficient alkenes and imines, such as para-quinone methides (p-QMs) and aurone-derived azadienes, respectively, is reported here for the first time. While p-QMs undergo exclusive and hitherto unreported 1,6-addition of bromoform to afford benzylic tribromomethylated diarylmethanes, aurone-derived azadienes undergo both 1,2- and 1,4-additions to furnish α- and γ-tribromomethylamines. A mechanism involving the intermediacy of the tribromomethyl radical has been proposed based on control experiments and EPR studies. Representative synthetic transformations have also been carried out.

Supporting Information



Publication History

Received: 21 May 2024

Accepted after revision: 26 June 2024

Accepted Manuscript online:
26 June 2024

Article published online:
25 July 2024

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