Origins of stereoselectivity in intramolecular Diels-Alder cycloadditions of dienes and dienophiles linked by ester and amide tethers.
نویسندگان
چکیده
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.
منابع مشابه
I. New Cycloadditions for the Synthesis of Nitrogen Heterocycles
Alkyliminoacetonitrile derivatives were investigated as dienophiles in the Diels-Alder reaction. These activated imines react with dienes in intramolecular [4+2] cycloadditions to provide products with either the quinolizidine or indolizidine ring system, depending on the length of the tether connecting diene and dienophile. Quinolizidine cycloadducts are formed in good yield and with high ster...
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ورودعنوان ژورنال:
- The Journal of organic chemistry
دوره 66 6 شماره
صفحات -
تاریخ انتشار 2001