145106-32-7Relevant articles and documents
Acylammonium salts as dienophiles in diels-alder/lactonization organocascades
Abbasov, Mikail E.,Hudson, Brandi M.,Tantillo, Dean J.,Romo, Daniel
supporting information, p. 4492 - 4495 (2014/04/17)
α,I?-Unsaturated acylammonium salts, generated in situ from commodity acid chlorides and a chiral isothiourea organocatalyst, comprise a new and versatile family of chiral dienophiles for the venerable Diels-Alder (DA) cycloaddition. Their reactivity is unveiled through a highly diastereo- and enantioselective Diels-Alder/lactonization organocascade that generates cis- and trans-fused bicyclic I?- and I??-lactones bearing up to four contiguous stereocenters. Moreover, the first examples of DA-initiated, stereodivergent organocascades are described delivering complex scaffolds found in bioactive compounds. The origins of stereoselectivity are rationalized through computational studies. In addition, the utility of this methodology is demonstrated through a concise approach to the core structure of glaciolide and formal syntheses of fraxinellone, trisporic acids, and trisporols.
