Oxa-Michael-initiated cascade reactions of levoglucosenone

Julian Klepp; Thomas Bousfield; Hugh Cummins; Sarah V A-M Legendre; Jason E Camp; Ben W Greatrex

doi:10.3762/bjoc.18.151

Oxa-Michael-initiated cascade reactions of levoglucosenone

Beilstein J Org Chem. 2022 Oct 13:18:1457-1462. doi: 10.3762/bjoc.18.151. eCollection 2022.

Authors

Julian Klepp¹, Thomas Bousfield², Hugh Cummins¹, Sarah V A-M Legendre¹, Jason E Camp², Ben W Greatrex¹

Affiliations

¹ School of Rural Medicine, University of New England, Armidale, NSW, 2351, Australia.
² Department of Chemical Sciences, School of Applied Sciences, University of Huddersfield, Queensgate, Huddersfield, United Kingdom.

Abstract

The reactions of aromatic aldehydes and levoglucosenone promoted by methoxide gives bridged α,β-unsaturated ketones, formed by a series of oxa-Michael-initiated cascade reactions in yields of up to 91% (14 examples). A complex series of equilibria operate during the reaction, and the formation of the bridged species is thermodynamically favored, except in the case of 5-methylfurfural and pyrrole-2-carboxaldehyde. This is the first report detailing this type of aldol/Michael cascade involving oxa-Michael initiation.

Keywords: cascade reactions; green chemistry; levoglucosenone; oxa-Michael reaction.

Grants and funding

This research was supported by an Australian Government Research Training Program (RTP) Scholarship, and was supported by the School of Applied Sciences at the University of Huddersfield (studentship T. W. B.)