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Intramolecular Wittig Reaction (intramolecular + wittig_reaction)

Distribution by Scientific Domains
Chemistry100%

Selected Abstracts

Domino Aza-Claisen/Mannich Cyclization Reaction from a Chiral ,-Alkoxy Enamine or Sequential Alkylation of an ,-Alkoxy Ester Enolate or Nitrile Anion, Followed by an Intramolecular Wittig Reaction: Two (3+2) Annulation Routes to Homochiral 4-Alkyl-4-hydroxy-2-cyclopentenone Synthesis

EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 14 2003
Cyrille Kuhn
Abstract A study on the enantioselective synthesis of 4-alkyl-4-hydroxyalkylidene-cyclopentenone prostaglandins is reported. Two (3+2) annulation processes allow the synthesis of homochiral 4-alkyl-4-hydroxy-2-cyclopentenones 4,5, 10,11, and 17. The first process involves a domino aza-Claisen/Mannich cyclization reaction, resulting from the alkylation of an ,-alkoxy-enamine, derived from chiral ,-alkoxy aldehydes 1, 9, or 16 with 3-iodo-2-(methoxymethoxy)prop-1-ene (3) as the acetonyl equivalent. The second process is based on the sequential alkylation of esters 21, 39, or nitrile 20 with acetonyl equivalents 3 or 25, followed by an intramolecular Wittig reaction. As an application, the synthesis of the naturally occurring alkylidene-cyclopentenone prostaglandin clavulone II from the spiro[cyclopentene-furan]one 5 and the formal total synthesis of (+/-)-untenone 19 has been carried out. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003) [source]

Microwave Assisted Intramolecular Wittig Reaction: A Facile Method for the Synthesis of Conjugated Acetylenes.

CHEMINFORM, Issue 34 2003
V. V. V. N. S. Rama Rao
Abstract For Abstract see ChemInform Abstract in Full Text. [source]

Domino Aza-Claisen/Mannich Cyclization Reaction from a Chiral ,-Alkoxy Enamine or Sequential Alkylation of an ,-Alkoxy Ester Enolate or Nitrile Anion, Followed by an Intramolecular Wittig Reaction: Two (3+2) Annulation Routes to Homochiral 4-Alkyl-4-hydroxy-2-cyclopentenone Synthesis

EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 14 2003
Cyrille Kuhn
Abstract A study on the enantioselective synthesis of 4-alkyl-4-hydroxyalkylidene-cyclopentenone prostaglandins is reported. Two (3+2) annulation processes allow the synthesis of homochiral 4-alkyl-4-hydroxy-2-cyclopentenones 4,5, 10,11, and 17. The first process involves a domino aza-Claisen/Mannich cyclization reaction, resulting from the alkylation of an ,-alkoxy-enamine, derived from chiral ,-alkoxy aldehydes 1, 9, or 16 with 3-iodo-2-(methoxymethoxy)prop-1-ene (3) as the acetonyl equivalent. The second process is based on the sequential alkylation of esters 21, 39, or nitrile 20 with acetonyl equivalents 3 or 25, followed by an intramolecular Wittig reaction. As an application, the synthesis of the naturally occurring alkylidene-cyclopentenone prostaglandin clavulone II from the spiro[cyclopentene-furan]one 5 and the formal total synthesis of (+/-)-untenone 19 has been carried out. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003) [source]

ChemInform Abstract: An Efficient One-Pot Synthesis of Trifluoromethyl-Substituted Cyclobutene Derivatives.

CHEMINFORM, Issue 38 2010
Mohmmad Hossein Mosslemin
Abstract Cyclobutene derivatives (III) are obtained via intramolecular Wittig reaction between 1,1,1-trifluorobutane-2,4-diones and ethyl phenylpropiolate. [source]