Mild conversion of propargylic alcohols to α,β-unsaturated enones in ionic liquids (ILs); A new 'metal free' life for the Rupe rearrangement
A mild and selective transition metal free protocol for the conversion of propargylic alcohols to cyclic and acyclic α,β-unsaturated enones via the Rupe rearrangement is reported. The method utilizes the Brønsted acidic ionic liquid [BMIM-SO3H][OTf] as catalyst and [BMIM][PF 6] as solvent and offers the potential for recycling and reuse of the IL solvent. The feasibility to synthesize bicyclic fused cyclopentenone derivatives via a Rupe → Aldol → Nazarov sequence utilizing this protocol has also been demonstrated. © 2013 Elsevier Ltd. All rights reserved.
Digital Object Identifier (DOI)
Nandi, Rathman, B. M., & Laali, K. K. (2013). Mild conversion of propargylic alcohols to α,β-unsaturated enones in ionic liquids (ILs); a new “metal free” life for the Rupe rearrangement. Tetrahedron Letters, 54(46), 6258–6263. https://doi.org/10.1016/j.tetlet.2013.09.028