[...]... Kasuga 81 6-8 580 Japan Email: kanemasa@cm.kyushu-u.ac.jp Fax: +8 1-9 2-5 8 3-7 802 Shu Kobayashi Graduate School of Pharmaceutical Sciences The University of Tokyo Hongo, Bunkyo-ku Tokyo 11 3-0 033 Japan Email: skobayas@mol.f.u-tokyo.ac.jp Fax: +8 1-3 -5 68 4-0 634 Cycloaddition Reactions in Organic Synthesis Edited by S Kobayashi and K A Jorgensen Copyright © 2001 Wiley-VCH Verlag GmbH ISBNs: 3-5 2 7-3 015 9-3 (Hardcover);... Diels-Alder reactions are categorized according to the metal of the chiral Lewis acid In general, the dienophiles used in the Diels-Alder reaction are categorized into two groups – those which bind to the Lewis acid at one point and those which bind at two points a,b-Unsaturated aldehydes and esters belong to the first category; 3-alkenoyl-1,3-oxazolidin-2-ones (abbreviated to 3-alkenoyloxazolidinones),... Ruppin in 1878, German Consul-General in Boston from 1926 to 1938, and who died in Siberia in Soviet internment in 1943 [4] [6] See, e.g., Otto Paul Hermann Diels in Nobel Laureate in Chemistry 1901–1992, L K James (Ed.), American Chemical Society 1994, p 332 3 Cycloaddition Reactions in Organic Synthesis Edited by S Kobayashi and K A Jorgensen Copyright © 2001 Wiley-VCH Verlag GmbH ISBNs: 3-5 2 7-3 015 9-3 ... substituent, tert-butyl acrylate reacts with cyclopentadiene to give the adduct in good optical purity (92% ee) Methyl acrylate and phenyl acrylate underwent cycloadditions with lower selectivities 1.2.3 The Asymmetric Diels-Alder Reaction of 3-Alkenoyl-1,3-oxazolidin-2-ones as Dienophile Chiral 3-alkenoyl-1,3-oxazolidin-2-ones have been developed and used in highly diastereoselective Diels-Alder reactions. .. efficiently to give the cycloadduct in over 90% ee Since Narasaka’s work the Diels-Alder reaction of 3-alkenoyl1,3-oxazolidin-2-ones has come to be regarded as a test case for newly-developed chiral Lewis acids having two-point binding ability, because the cycloadducts obtained are synthetically useful chiral building blocks Complexes derived from many kinds of metal, including Al(III), Mg(II), Cu(II), Fe(III),... [26] (Scheme 1.34) In this reaction these dienophiles are highly reactive compared with the corresponding 1.2 The Chiral Lewis Acid-catalyzed Diels-Alder Reaction Scheme 1.33 ester Lewis acids such as Et2AlCl coordinate to the dienophile in a two-point binding fashion (Fig 1.5) After Evans’s investigations of the diastereoselective reactions of chiral 3-alkenoyl-1,3-oxazolidin-2-ones, many chiral Lewis... Diels-Alder Reactions wis acids effective for each type of dienophile In this review, Diels-Alder reactions are classified by dienophile type – a,b-unsaturated aldehydes, a,b-unsaturated esters, 3-alkenoyl-1,3-oxazolidin-2-ones, and others The asymmetric Diels-Alder reaction is a rapidly expanding area and many interesting results have appeared This review deals only with catalytic asymmetric homo-Diels-Alder... applied to the Diels-Alder reaction of their achiral 3-alkenoyl1,3-oxazolidin-2-one counterparts Scheme 1.34 The first successful application of a chiral Lewis acid to the Diels-Alder reaction of these 3-alkenoyl-1,3-oxazolidin-2-ones was Narasaka’s TADDOL-based, chiral titanium catalyst in 1986 (vide infra) [27] A catalytic amount of this chiral titanium reagent can promote the Diels-Alder reaction highly.. .Cycloaddition Reactions in Organic Synthesis Edited by S Kobayashi and K A Jorgensen Copyright © 2001 Wiley-VCH Verlag GmbH ISBNs: 3-5 2 7-3 015 9-3 (Hardcover); 3-5 2 7-6 002 5-6 (Electronic) List of Contributors Gregory Beutner Department of Chemistry University of Illinois 245 Roger Adams Laboratory PO Box 18 600 S Mathews Avenue Urbana, IL 61801 USA Dominic M T Chan DuPont Crop Protection Stine-Haskell... determination of the X-ray structure of the ligand has suggested the occurrence of p-stacking of the 2,6-diisopropoxybenzene ring and coordinated aldehyde [5 c] Because of this stacking, the si face of the CAB-coordinated a,b-unsaturated aldehyde is sterically shielded (Fig 1.1) 1.2 The Chiral Lewis Acid-catalyzed Diels-Alder Reaction Fig 1.1 CAB catalyst 3 and methacrolein The intramolecular Diels-Alder . Wiley-VCH Verlag GmbH ISBNs: 3-5 2 7-3 015 9-3 (Hardcover); 3-5 2 7-6 002 5-6 (Electronic) Edited by Sh u Kobayashi and Karl Anker Jørgensen Cycloaddition Reactions in Organic Synthesis Cycloaddition Reactions. Transition-state Structures 303 8.3 Hetero-Diels-Alder Reactions 314 8.3.1 Frontier-molecular-orbital Interactions for Hetero-Diels-Alder Reactions 314 8.3.2 Normal Electron-demand Hetero-Diels-Alder Reactions. Reactions 2000. ISBN 3-5 2 7-2 995 0-5 Yamamoto, H. Lewis Acids in Organic Synthesis. A Comprehensive Handbook in Two Volumes 2000. ISBN 3-5 2 7-2 957 9-8 Rück-Braun, K. and Kunz, H. Chiral Auxiliaries in Cycloadditions 1999.