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Synlett 2016; 27(03): 450-454
DOI: 10.1055/s-0035-1560823
DOI: 10.1055/s-0035-1560823
letter
On the Solvent-Dependent Bromination of Dihydroazulenes
Further Information
Publication History
Received: 04 September 2015
Accepted after revision: 29 September 2015
Publication Date:
13 November 2015 (online)
![](https://www.thieme-connect.de/media/synlett/201603/lookinside/thumbnails/st-2015-d0695-l_10-1055_s-0035-1560823-1.jpg)
Abstract
Bromination of 1,8a-dihydroazulene-1,1-dicarbonitriles (DHA) followed by elimination of HBr was previously shown to be an important protocol for functionalizing these molecular photoswitches in the seven-membered ring (at C7). Here we show systematically how the outcome of the bromination reaction depends on the electronic character of an aryl substituent at the C2 position of DHA, and the solvent polarity as the reaction can lead to either the addition product or to the corresponding 2-aryl-1-bromo-3-cyanoazulene.
Supporting Information
- Supporting information for this article is available online at http://dx.doi.org/10.1055/s-0035-1560823.
- Supporting Information
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References and Notes
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