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Synthesis 2019; 51(12): 2579-2583
DOI: 10.1055/s-0037-1610703
DOI: 10.1055/s-0037-1610703
paper
Reactions of t-Boc-Protected Amines with Difluorocarbene
Further Information
Publication History
Received: 16 January 2019
Accepted after revision: 11 March 2019
Publication Date:
06 May 2019 (online)
Abstract
The reactions of t-Boc-protected secondary and primary amines with difluorocarbene generated from trimethylsilyl (fluorosulfonyl)difluoroacetate [Me3SiOC(O)CF2SO2F] (TFDA) in toluene at 110 °C results in the replacement of t-Bu by difluoromethyl in the t-Boc group. This reaction can be carried out in the presence of CH2Br and COOMe moieties in the structure of the protected amine. In the example of a t-Boc-protected amine containing a C=C double bond, replacement of the t-Bu group and/or cyclodifluoropropanation takes place. Difluoromethyl esters are shown to react with primary and secondary amines yielding the corresponding ureas.
Key words
t-Boc group - trimethylsilyl (fluorosulfonyl)difluoroacetate - t-Bu/CHF2 replacement - difluoromethylcarbamate - acylation - ureaSupporting Information
- Supporting information for this article is available online at https://doi.org/10.1055/s-0037-1610703.
- Supporting Information
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