Unusual Diastereoselectivity in Intramolecular Diels-Alder Reactions of Substituted 3,5-Hexadienyl Acrylates. Preference for a Boatlike Structure of the Six-Atom Tether Due to Ester Overlap.
نویسندگان
چکیده
Thermolysis of the 3,5-hexadienyl acrylates (a) proceeds via the transition state E in which the connecting chain adopts a boatlike conformation due to a preference for maintaining ester overlap to afford the products b with good diastereoselectivity.
منابع مشابه
Origins of stereoselectivity in intramolecular Diels-Alder cycloadditions of dienes and dienophiles linked by ester and amide tethers.
B3LYP/6-31+G(d) calculations of structures and relative energies for competing transition states for intramolecular Diels-Alder reactions of substituted 3,5-hexadienyl acrylates and acrylamides show that boatlike conformations are sometimes favored in the forming ring that includes the tether.
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ورودعنوان ژورنال:
- Organic letters
دوره 2 13 شماره
صفحات -
تاریخ انتشار 2000