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Synthesis and Properties of 2-Oxa-6-azaspiro[3.3]heptane Sulfonate Salts
Received: 13 December 2016
Accepted after revision: 31 January 2017
02 March 2017 (online)
An improved synthesis of the bicyclic spiro compound 2-oxa-6-azaspiro[3.3]heptane is presented. While this compound is often isolated as an oxalate salt, its isolation as a sulfonic acid salt yields a more stable and more soluble product. With these improved properties access to a wider range of reaction conditions with the spirobicyclic 2-oxa-6-azaspiro[3.3]heptane has been enabled.
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