title: Distortion, Tether, and Entropy Effects on Transannular Diels-Alder Cycloaddition Reactions of 10-18-Membered Rings.
abstract: Density functional theory calculations were performed on a set of 13 transannular Diels-Alder (TADA) reactions with 10-18-membered rings. The results were compared with those for bimolecular and intramolecular Diels-Alder reactions in order to investigate the controlling factors of the high TADA reactivities. The effects of tether length, heteroatoms, and alkynyl dienophiles on reactivity were analyzed. We found a correlation between tether length and reactivity, specifically with 12-membered macrocycles undergoing cycloaddition most readily. Furthermore, modifying 12-membered macrocycles by heteroatom substitution and utilizing alkynyl dienophiles enhances the reaction rates up to 10(5)-fold.
authors.affiliation: Department of Chemistry and Biochemistry and ‡Department of Chemical and Biochemical Engineering, University of California , Los Angeles, California 90095, United States.
authors.forename: Cyndi Qixin
authors.initials: CQ
authors.lastname: He
authors.affiliation: Department of Chemistry and Biochemistry and ‡Department of Chemical and Biochemical Engineering, University of California , Los Angeles, California 90095, United States.
authors.forename: Tiffany Q
authors.initials: TQ
authors.lastname: Chen
authors.affiliation: Department of Chemistry and Biochemistry and ‡Department of Chemical and Biochemical Engineering, University of California , Los Angeles, California 90095, United States.
authors.forename: Ashay
authors.initials: A
authors.lastname: Patel
authors.affiliation: Department of Chemistry and Biochemistry and ‡Department of Chemical and Biochemical Engineering, University of California , Los Angeles, California 90095, United States.
authors.forename: Sedef
authors.initials: S
authors.lastname: Karabiyikoglu
authors.affiliation: Department of Chemistry and Biochemistry and ‡Department of Chemical and Biochemical Engineering, University of California , Los Angeles, California 90095, United States.
authors.forename: Craig A
authors.initials: CA
authors.lastname: Merlic
authors.affiliation: Department of Chemistry and Biochemistry and ‡Department of Chemical and Biochemical Engineering, University of California , Los Angeles, California 90095, United States.
authors.forename: K N
authors.initials: KN
authors.lastname: Houk