Pancholi, Alpa, Iacobini, Greg, Clarkson, Guy, Porter, David and Shipman, Michael (2018) Synthesis of 4,5-Diazaspiro[2.3]hexanes and 1,2-Diazaspiro[3.3]heptanes as Hexahydropyridazine Analogues. Journal of Organic Chemistry, 83 (1). pp. 491-498. ISSN 15206904

Abstract

4,5-Diazaspiro[2.3]hexanes are made by dihalocarbene addition across the exocyclic double bond of readily accessible 3-alkylidene-1,2-diazetidines. Using difluorocarbene, generated from TMSCF3/NaI, these spirocycles were produced in yields up to 97% by stereospecific addition across the alkene. Lower yields (up to 64%) were observed using more reactive dichlorocarbene, due to competitive insertion of the carbene into the N-N bond. Larger 1,2-diazaspiro[3.3]heptanes are produced by [2 + 2] cycloaddition of 3-alkylidene-1,2-diazetidines with tetracyanoethylene (TCNE) in up to 99% yield.

Item Type:	Article
Date Deposited:	17 Apr 2018 00:45
Last Modified:	25 Jan 2019 00:45
URI:	https://oak.novartis.com/id/eprint/34281