One-pot synthesis of stable phosphonium ylides using 2-aminothiophenol

Stabilized phosphorus ylides, versatile intermediates in synthetic organic chemistry can be prepared by the novel reaction of dialkyl acetylenedicarboxylates (DAAD), triphenylphosphine (TPP) and acids such as phenols, imides, amides, enols, oximes and alcohols. The reaction involves an intermediate formed by the 1:1 conjugate addition reaction of the TPP to DAAD and concomitant protonation of the intermediate by an acid leads to vinyltriphenylphosphonium salts. The salts are unstable intermediates and converted to stabilized phosphorus ylides via Michael addition reaction. The stabilized phosphorus ylides are able to take part in the normal intramolecular Wittig reactions but they are not generally able to participate in the normal intermolecular Wittig reactions. The intermolecular Wittig reactions of the ylides are observed only with highly electron-poor carbonyl groups such as indane-1,2,3-trione. The ylides are converted to electron-poor alkenes via elimination of TPP in solvent-free conditions. Almost all of the final products are valuable families of compounds. †Dedicated to Professor Issa Yavari on the occasion of his 59th birthday.

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“…The reaction of some other strong SH-acids with DAAD in the presence of TPP lead to the corresponding phosphoranes [74,[162][163][164].…”

Section: Reaction Of Triphenylphosphine Dialkyl Acetylenedicarboxylamentioning

confidence: 99%

Synthesis and Reactions of Stabilized Phosphorus Ylides

Ramazani

Kazemizadeh

Ahmadi³

et al. 2008

COC

107

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“…[28][29][30][31] The 1 H NMR spectrum of compound 3a exhibited two singlets (δ 3.06 and 3.87) arising from the methoxy group in the Z-isomer, and two singlets at 3.42 and 3.78 ppm for that in the E-isomer. The methyl group at 3.06 in the Z-isomer is shielded due to the anisotropic effect of a phenyl group of the triphenylphosphine unit.…”

Section: Methodsmentioning

confidence: 99%

One-pot synthesis of stable phosphorus ylides using aldehyde phenylhydrazone derivatives

Maghsoodlou¹,

Hazeri²,

Heydari³

et al. 2009

Arkivoc

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Stable crystalline phosphorus ylides were obtained in excellent yields from the 1:1:1 addition reaction between triphenylphosphine and dialkyl acetylenedicarboxylates in the presence of phenylhydrazone derivatives, such as 1-benzylidene-2-phenylhydrazine, 1-(3-chlorobenzylidene)-2-phenylhydrazine, 1-(2,4-dinitrobenzylidene)-2-phenylhydrazine, 1-(4-nitrobenzylidene)-2-phenylhydrazine, 1-(2-fluorobenzylidene)-2-phenylhydrazine, 1-(4-fluorobenzylidene)-2-phenylhydrazine and 1-(2,4-dichlorobenzylidene)-2-phenylhydrazine. These stable ylides exist in solution as a mixture of two geometrical isomers as a result of the restricted rotation around the carbon-carbon partial double bond resulting from the conjugation of the ylide moiety with the adjacent carbonyl group.

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“…Thus, e.g., new phosphorus ylides have been obtained in excellent yield from the reactions of triphenylphosphine, dimethyl acetylenedicarboxylate and strong NH acids, including pyrroles and indoles, 426 hydantoins, 427 benzimidazoles, 428 saccharin, 429 trifluoroacetamide, 430 phthalimide and succinimide. 431,432 New ylides have also been isolated from the related reactions of triphenylphosphine, dimethyl acetylenedicarboxylate and primary aromatic amines, 433 including various aminophenols, 434 2-aminothiophenol, 435 and o-phenylenediamine. 436 Other NH compounds used to trap the initial dipolar adduct in the triphenylphosphinedimethyl acetylenedicarboxylate system include perimidines, 437 and various amides derived from aromatic amines, the latter reactions providing routes to 5-oxo-4,5-dihydro-1H-pyrroles.…”

Section: Miscellaneous Methods Of Preparing Phosphinesmentioning

confidence: 99%

Phosphines and Related Tervalent Phosphorus Systems

2006

Organophosphorus Chemistry

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One-pot synthesis of stable phosphonium ylides using 2-aminothiophenol

Cited by 39 publications

References 22 publications

Synthesis and Reactions of Stabilized Phosphorus Ylides

Synthesis and Reactions of Stabilized Phosphorus Ylides

One-pot synthesis of stable phosphorus ylides using aldehyde phenylhydrazone derivatives

Phosphines and Related Tervalent Phosphorus Systems

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