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Titolo:
Reactions of 1,5-dienes with ruthenium tetraoxide: Stereoselective synthesis of tetrahydrofurandiols
Autore:
Albarella, L; Musumeci, D; Sica, D;
Indirizzi:
Univ Naples Federico II, Dipartimento Chim Organ & Biol, I-80134 Naples, Italy Univ Naples Federico II Naples Italy I-80134 Biol, I-80134 Naples, Italy
Titolo Testata:
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
fascicolo: 5, , anno: 2001,
pagine: 997 - 1003
SICI:
1434-193X(200103):5<997:RO1WRT>2.0.ZU;2-I
Fonte:
ISI
Lingua:
ENG
Soggetto:
CARBON DOUBLE-BONDS; POLYOXYGENATED STEROIDS; RUO4; ACETOGENINS; ACETATE; DIESTER;
Keywords:
ruthenium; alkenes; asymmetric catalysis; oxygen heterocycles; cyclization;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Physical, Chemical & Earth Sciences
Citazioni:
29
Recensione:
Indirizzi per estratti:
Indirizzo: Sica, D Univ Naples Federico II, Dipartimento Chim Organ & Biol, Via Mezzocannone 16, I-80134 Naples, Italy Univ Naples Federico II Via Mezzocannone 16 Naples Italy I-80134
Citazione:
L. Albarella et al., "Reactions of 1,5-dienes with ruthenium tetraoxide: Stereoselective synthesis of tetrahydrofurandiols", EUR J ORG C, (5), 2001, pp. 997-1003

Abstract

An improved procedure for the ruthenium tetraoxide catalysed oxidation of 1,5-dienes, employing 0.05 equiv, of the catalyst RuO2. 2H(2)O, 2.5 equiv, of NaIO4 as a stoichiometric oxidant, and a biphasic solvent system of AcOEt/(CH3)(2)CO/H2O H2O (2:1:1, v/v/v), is presented. Reactions of 1,5-dienes 1, 3, and 5 furnished the new cis-tetrahydrofuran products 2, 4, 6, and 7 with total stereospecificity, The structures of the products have been established on the basis of NMR and MS data, as well as chemical evidence. Application of this procedure to geranyl acetate (8) and neryl acetate (12) afforded the cis-tetrahydrofuran derivatives 9, 10, and 13 in high yields, accompanied by small amounts of trans-tetrahydrofurandiols 11 and 14. These products are the same as those obtained by Sharpless et al. upon RuO4-catalysed oxidation of 8 and 12 in the biphasic solvent system CCl4/CH3CN/H2O (2:2:3, v/v/v), but our procedure has the advantages of higher stereospecificity, a greater material recovery (about 90%), and a more simple work-up. The oxidation of 1,5-dienes proceeds stereoselectively by syn oxygen addition toboth double bonds. The formation of tetrahydrofuran derivatives is presumed to involve initial addition of RuO4 to one bond of the 1,5-diene to give a ruthenium(VI) diester, which subsequently undergoes conversion into the cyclic ether with participation of the second double bond.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 02/04/20 alle ore 19:08:25