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Synlett 2021; 32(01): 91-94
DOI: 10.1055/s-0040-1707311
DOI: 10.1055/s-0040-1707311
letter
Synthesis of gem-Difluoroalkenes via a Sequence of Hydroboration and 1,2-Elimination of α,β-Unsaturated Carbonyls
Financial support from the Natural Science Foundation of Jiangsu Province (BK20191197) is gratefully acknowledged.
Abstract
We reported a simple protocol for the synthesis of gem-difluoroalkenes via a reaction sequence of hydroboration and 1,2-elimination of α,β-unsaturated carbonyl substrates under mild conditions. Two steps of this method could be executed in one pot. The β-CF2H- and β-CFH2-α,β-unsaturated carbonyls can be obtained smoothly from the α,β-unsaturated gem-difluoroamide with NaH as the base and via a boration–1,2-elimination sequence.
Key words
gem-difluoroalkene - boration - 1,2-elimination - α,β-unsaturated carbonyls - fluoroalkeneSupporting Information
- Supporting information for this article is available online at https://doi.org/10.1055/s-0040-1707311.
- Supporting Information
Publication History
Received: 26 August 2020
Accepted after revision: 03 September 2020
Article published online:
14 October 2020
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For reviews on the synthesis of gem-difluoroalkenes and their applications in organic synthesis, see:
For recent examples of the gem-difluoroolefination of carbonyl compounds, see:
For selected examples of the gem-difluoroolefination of diazo compounds, see:
For selected examples of the synthesis of gem-difluoroalkenes via organometallic- or strong-base-mediated nucleophilic addition to trifluoromethyl alkenes involving β-F-elimination, see:
For selected examples, see: