[reaction: see text] The first catalytic, asymmetric 2,3-trans-selective heteroDiels-Alderreaction has been developed. The reactions of aldehydes with Danishefsky'sdienes proceeded smoothly to afford the pyranone derivatives in high yields with high trans-selectivities and enantioselectivities in the presence of a chiral zirconium complex, which was prepared from zirconium tert-butoxide and (R)-3
AnN,N′-Dioxide/In(OTf)3 Catalyst for the Asymmetric Hetero-Diels–Alder Reaction Between Danishefsky's Dienes and Aldehydes: Application in the Total Synthesis of Triketide
Chiral Hetero Diels−Alder Products by Enantioselective and Diastereoselective Zirconium Catalysis. Scope, Limitation, Mechanism, and Application to the Concise Synthesis of (+)-Prelactone C and (+)-9-Deoxygoniopypyrone
enantioselectivities in the reaction with 4-methyl Danishefsky's diene. This is the first example of catalyticasymmetric trans-selective hetero Diels-Alderreactions of aldehydes. Furthermore, asymmetric HDA reactions with 4-benzyloxy Danishefsky's dienes were conducted to afford 2,3-cis-pyranone derivatives in high selectivities. Isolation of an intermediate of this asymmetric hetero Diels-Alderreaction indicated