Inoue K, Mori A, Okano K. Ultrafast Halogen Dance Reactions of Bromoarenes Enabled by Catalytic Potassium Hexamethyldisilazide.
Chemistry 2024;
30:e202400104. [PMID:
38329223 DOI:
10.1002/chem.202400104]
[Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 02/08/2024] [Accepted: 02/08/2024] [Indexed: 02/09/2024]
Abstract
Lochmann-Schlosser base, a stoichiometric combination of nBuLi and KOtBu, is commonly used as a superbase for deprotonating a wide range of organic compounds. In the present study, we report that catalytic potassium hexamethyldisilazide (KHMDS) exhibits higher catalytic activity than KOtBu for successive bromine-metal exchanges. Accordingly, 1-10 mol% of KHMDS dramatically enhances halogen dance reactions to introduce various electrophiles to bromopyridine, bromoimidazole, bromothiophene, bromofuran, and bromobenzene derivatives with the bromo group translocated from the original position. A dual catalytic cycle is proposed to explain the ultrafast bromine transfer.
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