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Diels-Alder in Aqueous Molecular Hosts: Unusual Regioselectivity and Efficient Catalysis Michito Yoshizawa, Masazumi Tamura, Makoto Fujita* Science 2006 , 312 , 251-254. Diels-Alder Reaction. Rebek J. et al. Nature 1997 , 385 , 50-52. Epoxidation. Angew. Chem. Int. Ed. Engl.
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Diels-Alder in Aqueous Molecular Hosts: Unusual Regioselectivity and Efficient Catalysis Michito Yoshizawa, Masazumi Tamura, Makoto Fujita* Science2006, 312, 251-254.
Diels-Alder Reaction Rebek J. et al. Nature1997, 385, 50-52.
Epoxidation Angew. Chem. Int. Ed. Engl. 2001, 40, 4239-4242.
aza-Cope rearrangement Fe Angew. Chem. Int. Ed. Engl. 2004, 43, 6748-6751.
Regioselective cycloaddition Org. Lett. 2002, 4, 327-329.
Diels-Alder Reaction anthracenes phthalimides 1 9 10 4 Barrier (kJ mol-1) 3a 79.4 3b 49.8 ΔE = 29.6 Chem. Phys. Lett.2003, 368, 630-638.
B-ring A-ring J. Am. Chem. Soc. 1965, 87, 4649-4651 .
H2O 70 oC 1’ Nature 1995, 378, 469-471. J. Am. Chem. Soc. 2004, 126, 6846-6847.
Cyclic siloxane formation RSi(OMe)3 J. Am. Chem. Soc. 2001, 123, 10454-10459
Td 5 hr C3v
Syn-1,4-Diels-Alder adduct (5) Yield : > 98 % No other : 1,9-adduct or anti-1,4-adduct without 1 9 ,10-Diels-Alder adduct 44 %
π-π stacking interaction (3.3 Å)
(10 mmol%) 5 hr > 99 %
aromatic-aromatic or charge-transfer interactions the encapsulated product is considerably destabilized and smoothly replaced by incoming reagents the host-guest aromatic stacking interaction