4.2.8. Reductive Coupling 3109 5. Reaction of Aromatic Compounds 3110 5.1. Electrophilic Substitutions 3110 5.2. Radical Substitution 3111 5.3. Oxidative Coupling 3111 5.4. Photochemical Reactions 3111 6. Reaction of Carbonyl Compounds 3111 6.1. Nucleophilic Additions 3111 6.1.1. Allylation 3111 6.1.2. Propargylation 3120 6.1.3. Benzylation 3121 6.1.4. Arylation/Vinylation 3121 6.1.5. Alkynylation 3121 6.1.6. Alkylation 3121 6.1.7. Reformatsky-Type Reaction 3122 6.1.8. Direct Aldol Reaction 3122 6.1.9. Mukaiyama Aldol Reaction 3124 6.1.10. Hydrogen Cyanide Addition 3125 6.2. Pinacol Coupling 3126 6.3. Wittig Reactions 3126 7. Reaction of R,â-Unsaturated Carbonyl Compounds 3127

Organic Reactions in Aqueous Media with a Focus on Carbon−Carbon Bond Formations: A Decade Update

A new iron(III) halide-promoted aza-Prins cyclization between γ,δ-unsaturated tosylamines and aldehydes provides six-membered azacycles in good to excellent yields. The process is based on the consecutive generation of γ-unsaturated-iminium ion and further nucleophilic attack by the unsaturated carbon−carbon bond. Homoallyl tosylamine leads to trans-2-alkyl-4-halo-1-tosylpiperidine as the major isomer. In addition, the alkyne aza-Prins cyclization between homopropargyl tosylamine and aldehydes gives 2-alkyl-4-halo-1-tosyl-1,2,5,6-tetrahydropyridines as the only cyclic products. The piperidine ring is widely distributed throughout Nature, e.g., in alkaloids,1 and is an important scaffold for drug discovery, being the core of many pharmaceutically significant compounds.2,3 The syntheses of these type of compounds have been extensively studied in the development of new drugs containing six-membered-ring heterocycles.4 Reactions between N-acyliminium ions and nucleophiles, also described as amidoalkylation or Mannich-type condensations, have been frequently used to introduce substituents at the R-carbon of an amine.5 There are several examples that involve an intramolecular attack of a nucleophilic olefin into an iminium cation for the construction of a heterocyclic ring system.6 Traditionally, the use of hemiaminals or their derivatives as precursors of N-acyliminium intermediates has been a common two-step strategy in these reactions.6a Among this type of cyclization is the aza-Prins cyclization,7 which uses alkenes as intramolecular nucleophile. However, cy† X-ray analysis. E-mail address: malopez@ull.es. (1) (a) Fodor, G. B.; Colasanti, B. Alkaloids: Chemical and Biological PerspectiVes; Pelletier, S. W., Ed.; Wiley: New York, 1985; Vol. 23, pp 1-90. (b) Baliah, V.; Jeyarama, R.; Chandrasekaran, L. Chem. ReV. 1983, 83, 379-423. (2) Watson, P. S.; Jiang, B.; Scott, B. Org. Lett. 2000, 2, 3679-3681. (3) Horton, D. A.; Bourne, G. T.; Smythe, M. L. Chem. ReV. 2003, 103, 893-930. (4) Buffat, M. G. P. Tetrahedron 2004, 60, 1701-1729 and references therein. (5) Speckamp, W. N.; Moolenaar, M. J. Tetrahedron 2000, 56, 3187- 3856 and references therein. (6) (a) Hiemstra, H.; Speckamp, W. N. In ComprehensiVe Organic Synthesis; Trost, B. M., Fleming, O., Heathcock, C. H., Eds.; Pergamon: New York, 1991; Vol. 2, pp 1047-1081. (b) Speckamp, W. N.; Hiemstra, H. Tetrahedron 1985, 41, 4367-4416. (7) (a) Dobbs, A. P.; Guesne, S. J. J.; Hursthouse, M. B.; Coles, S. J. Synlett 2003, 11, 1740-1742. (b) Dobbs, A. P.; Guesne, S. J. J.; Martinove, S.; Coles, S. J.; Hursthouse, M. B. J. Org. Chem. 2003, 68, 7880-7883. (c) Hanessian, S.; Tremblay, M.; Petersen, F. W. J. Am. Chem. Soc. 2004, 126, 6064-6071 and references therein. (d) Dobbs, A. P.; Guesne, S. J. Synlett 2005, 13, 2101-2103. ORGANIC

Iron-Catalyzed Reactions in Organic Synthesis

Asymmetric 1,3-Dipolar Cycloaddition Reactions

1,2-Amino Alcohols and Their Heterocyclic Derivatives as Chiral Auxiliaries in Asymmetric Synthesis

http://aether.cmi.ua.ac.be/artikels/Artikels%20Gitte/Artikels/Reviews/Trans.%20Metal.%20catal.%20reactions%20Chem.%20rev.%20042127.pdf

Transition-Metal-Catalyzed Reactions in Heterocyclic Synthesis

Asymmetric Dipolar Cycloaddition of Nitrile Oxides to the α,. beta.-Unsaturated Esters Bearing an Imidazolidine Chiral Controller at the β-Position.

Michael Addition of Acyclic Lithium 1,3‐Dien‐2‐olates with α,. beta.‐Unsaturated Esters, Ketones, and Diesters.

En presence de bromure de lithium/1,8-diazabicyclo [5.4.0] undec-7-ene, de [(2,2-dimethylpropylidene)-amino] acetate de methyle et de 2-[(2,2-dimethylproylidene) amino] propanoate, obtention d'une addition anti- et syn-selective de Michael avec, respectivement, des isomeres E et Z d'esters α,β-insatures et des cetones. La cyclisation hydrolytique des composes d'addition de Michael conduit a des 5-oxopyrrolidine-2-carboxylates et a des 1-pyrroline-5-carboxylates

Stereoselective Michael Addition of the Imines of α-Amino Esters in the Presence of Lithium Bromide/1,8-Diazabicyclo(5.4.0)undec-7-ene.

PROBLEM TO BE SOLVED: To provide a suction device improved in accuracy of positioning suction ports of suction pads formed of elastic materials, and to provide a carrying device.SOLUTION: The suction device 20 includes a metal holder 30, four suction pads 40a-40d formed of elastic materials such as carbon-containing conductive rubbers, and a metal fixture 50 fixed to the holder 30 while pressing the suction pads 40a-40d against corresponding suction parts 33a-33d. The fixture 50 has an opening to which the suction ports 44 of the suction pads 40a-40d are exposed.

Suction device and carrying device

The Diels–Alder cycloaddition of 4-methylene-1,5-hexadien-3-ols with olefinic dienophiles such as dimethyl maleate, fumarate, and N-methylmaleimide produces 1-(1-cyclohexenyl)-2-propen-1-ols. These diene alcohols are oxidized with activated manganese(IV) oxide to give dienones, which are then treated with acid catalysts to undergo ready electrocyclization leading to hexahydroindenones with functional groups. Stereoselectivity at the electrocyclization step is found to depend upon the stereostructures of cyclohexene skeleton of the dienones as well as the reaction conditions.

Eiji Wada

Papers

Asymmetric Dipolar Cycloaddition of Nitrile Oxides to the α,. beta.-Unsaturated Esters Bearing an Imidazolidine Chiral Controller at the β-Position.

Michael Addition of Acyclic Lithium 1,3‐Dien‐2‐olates with α,. beta.‐Unsaturated Esters, Ketones, and Diesters.

Stereoselective Michael Addition of the Imines of α-Amino Esters in the Presence of Lithium Bromide/1,8-Diazabicyclo(5.4.0)undec-7-ene.

Suction device and carrying device

Synthesis of Hexahydroindenones Through a Diels-Alder Cycloaddition and Nazarov Cyclization Sequence of Triene Alcohols.