Phosphinemethylenes.<sup>1</sup> II. Triphenylphosphineacylmethylenes

Ramírez, Fausto; Dershowitz, Samuel

doi:10.1021/jo01352a010

Cited by 386 publications

(95 citation statements)

References 2 publications

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“…For both the six-and the eight-membered ring, the low value of the carbonyl frequency is similar to that found in other acylated ylids (35)(36)(37), and reflects the extent to which resonance such as that depicted in eq. 4 weakens the C=O double bond.…”

Section: Reactions Of Azaphosphorinssupporting

confidence: 73%

The deprotonation and rearrangement of N-methyl methylphosphazenium quaternary salts: a novel synthetic route to cyclic azaphosphorins

Oakley¹,

Paddock²

1977

Can. J. Chem.

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RICHARD T. OAKLEY and NORMAN L. PADDOCK. Can. J. Chem. 55, 3651 (1977). The N-methyl methylphosphazenium salts (NPMe,),,,.MeI and N3P3Ph4Me2.MeI can be deprotonated by a variety of bases to yield the novel azaphosphorins Me2,-,(NHMe)P,N,-,-CH (n = 3, 4) and Me(NHMe)Ph4P3N2CH, formed by a rearrangement in which the methylated nitrogen atom is displaced from the PN ring by the initially produced exocyclic methylene group. The 'H nmr spectra of the azaphosphorins indicate a rapid proton exchange between the endocyclic carbon and the exocyclic nitrogen, which can be slowed by the addition of an auxiliary base. When KO-t-Bu reacts with the quaternary salts, nucleophilic attack competes with proton removal, and the linear oxides (NHMe)(PMe2N).PMe20 (n = 2-4) have been isolated from these reactions. The azaphosphorins Me2,-l(NHMe)P,N,-lCH (n = 3, 4) are hydrolysed in aqueous ethanol to give the cyclic oxides Me2,-,(O)P,N,_ ,CH2, and react with methyl iodide by a proton transfer reaction to givelthe hydroiodides Me2.-,(NHMe)P.N,-,-CH.HI. Their reaction with benzoyl chloride leads to the derivatives Me7(NHMe)P4N3CCOPh and Me7(NMeCOPh)P3N2CCOPh, the initial substitution on carbon indicating that it is the primary basic centre. Model calculations of x-electron energies suggest that both the azaphosphorin rearrangement and the proton exchange reactions depend on the relative orbital electronegativity of the ring and exocyclic atoms, the less electronegative atom being more stable in the endocyclic position. Lorsque le KO-t-Bu rtagit avec les sels quaternaires, une attaque nucleophile concurrence l'abstraction du proton et il resulte de ces reactions des oxydes lintaires (NHMe)(PMe2N),PMe,0 (n = 2-4). Les azaphosphorines Me2.-,(NHMe)P.N,.. ,CH (n = 3, 4) sont hydrolyskes dans l'ethanol aqueux pour conduire aux oxydes cycliques Me2,-1-(O)P,N,-,CH2, et elles reagissent avec I'iodure de mCthyle par une reaction de transfert de protons pour conduire aux hydroiodures Me2,-,(NHMe)P,N, -lCH. HI. Elles rtagissent avec le chlorure de benzoyle pour conduire aux derives Me7(NHMe)P4N3CCOPh et Me7(NMeCOPh)P3N2CCOPh; la substitution initiale sur le carbone indique que celui-ci est le premier centre basique. Des calculs modeles des energies pour les electrons-n suggerent que tant le rearrangement des azaphosphorines que les reactions d'echange de protons dependent de l'electron6gativite relative des orbitales du cycle et des atomes exocycliques, I'atome le moins Clectrontgatif ttant plus stable en position endocyclique.[Traduit par le journal]

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Section: Reactions Of Azaphosphorinssupporting

confidence: 73%

The deprotonation and rearrangement of N-methyl methylphosphazenium quaternary salts: a novel synthetic route to cyclic azaphosphorins

Oakley¹,

Paddock²

1977

Can. J. Chem.

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“…The known ylides Ph 3 PCHA C H T U N G T R E N N U N G (C=O)Ph [28] and Ph 3 PCHA C H T U N G T R E N N U N G (C= O)-p-tol [29] were prepared by an alternative procedure. [30] The new ylide Ph 3 PCHA C H T U N G T R E N N U N G (C=O)S-i-Pr was synthesized analogously to the SEt homolog.…”

Section: Syntheses Of Educts O=cha C H T U N G T R E N N U N G (Ch 2 mentioning

confidence: 99%

Catalysis of Intramolecular Morita–Baylis–Hillman and Rauhut–Currier Reactions by Fluorous Phosphines; Facile Recovery by Liquid/Solid Organic/Fluorous Biphase Protocols Involving Precipitation, Teflon^® Tape, and Gore‐Rastex^® Fiber

Seidel

Gladysz

2008

Adv Synth Catal

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“…To a solution of 2-benzylidene-1,3-indandione (1) or 5-benzylidenebarbituric acid (11) (0.01 mole) in 20 mL of dry ethyl acetate was added a solution of the acylmethylenetriphenylphosphoranes 4a-d [22,23] (0.011 mole) in 30 mL of ethyl acetate, and the reaction mixture was refluxed for 15 hours. After the solvent was distilled off, the residue was crystallized from the appropriate solvent.…”

Section: General Proceduresmentioning

confidence: 99%

The reaction of active and stabilized phosphonium ylides with ?,?-unsaturated carbonyl compounds [1]

Soliman¹,

Said²,

Maigali³

1997

Heteroat. Chem.

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Phosphinemethylenes.¹ II. Triphenylphosphineacylmethylenes

Cited by 386 publications

References 2 publications

The deprotonation and rearrangement of N-methyl methylphosphazenium quaternary salts: a novel synthetic route to cyclic azaphosphorins

The deprotonation and rearrangement of N-methyl methylphosphazenium quaternary salts: a novel synthetic route to cyclic azaphosphorins

Catalysis of Intramolecular Morita–Baylis–Hillman and Rauhut–Currier Reactions by Fluorous Phosphines; Facile Recovery by Liquid/Solid Organic/Fluorous Biphase Protocols Involving Precipitation, Teflon^® Tape, and Gore‐Rastex^® Fiber

The reaction of active and stabilized phosphonium ylides with ?,?-unsaturated carbonyl compounds [1]

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Phosphinemethylenes.1 II. Triphenylphosphineacylmethylenes

Cited by 386 publications

References 2 publications

The deprotonation and rearrangement of N-methyl methylphosphazenium quaternary salts: a novel synthetic route to cyclic azaphosphorins

The deprotonation and rearrangement of N-methyl methylphosphazenium quaternary salts: a novel synthetic route to cyclic azaphosphorins

Catalysis of Intramolecular Morita–Baylis–Hillman and Rauhut–Currier Reactions by Fluorous Phosphines; Facile Recovery by Liquid/Solid Organic/Fluorous Biphase Protocols Involving Precipitation, Teflon® Tape, and Gore‐Rastex® Fiber

The reaction of active and stabilized phosphonium ylides with ?,?-unsaturated carbonyl compounds [1]

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Resources

About

Phosphinemethylenes.¹ II. Triphenylphosphineacylmethylenes

Catalysis of Intramolecular Morita–Baylis–Hillman and Rauhut–Currier Reactions by Fluorous Phosphines; Facile Recovery by Liquid/Solid Organic/Fluorous Biphase Protocols Involving Precipitation, Teflon^® Tape, and Gore‐Rastex^® Fiber