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Phospha-Mannich reaction

In the context of the phospha-Mannich reaction, secondary phosphine oxides were added on the C = N bond of imines in the presence of chiral guanidinium salt catalysts to give the a-aminophosphine oxides in an enantioselective way (Scheme 29). " ... [Pg.62]

It was found that in carrying out the Kabachnik-Fields (phospha-Mannich) reaction, there is no need for exotic catalysts, as MW irradiation of the solventless 3-component mixture led to the a-aminophosphine oxides in good yields (Scheme 7A) ... [Pg.81]

The Kabachnik-Fields (phospha-Mannich) reaction has been reviewed, including evidence for imine intermediates via in situ FT-IR studies. Solvent-free microwave conditions are particularly effective, with little call for catalysts. [Pg.10]

Kabachnik-Fields reaction (also called the phospha-Mannich reaction) is one of the oldest and perhaps the most commonly used for the synthesis of a-aminophosphonates. This reaction involves the condensation of primary or secondary amines, earbonyl eompounds (aldehydes and ketones) and >P(0)H speeies, espeeially diallqrl phosphites. [Pg.460]

The Keglevich group has continued to deal with environmentally friendly and P-heterocyclic chemistry. The solid liquid phase alkylation of P=0-functionalised CH acidic compounds was accomplished under phase transfer catalytic and microwave (MW) conditions." a-Hydroxy-benzylphosphine oxides were synthesized by the addition of diphenylphosphine oxide to the carbonyl group of substituted benzaldehydes under MW conditions." The double Kabachnik-Fields (phospha-Mannich) reaction was utilized in the preparation of bis(phosphinoxidomethyl)amines. The Diels Alder cycloadditions of 1,2-dihydrophosphinine oxides and subsequent... [Pg.69]

The double Kabachnik-Fields (phospha-Mannich) reaction of primary amines, two equivalents of paraformaldehyde and the same amount of diphenylphosphine oxide gave bis(diphenylphosphinoylmethyl)amines that were precursors of bidentate P-ligands after double deojq genation... [Pg.70]

The phospha-Mannich condensation of a-, (3- and y-amino acetals, paraformaldehyde and secondary phosphine oxides led to a),(i)-dialko g -all laminomethylphosphine oxides whose reaction with resorcinols or pyrogallol in boiling trifluoroacetic acid afforded (diallg lphosphinoyl-methyl-)(o),a)-diaiylallgrl)ammonium trifluoroacetates (Scheme 41). ... [Pg.113]

Phosphorus-containing Ring Systems. - A range of new chiral oxazaphospholidine oxides 266 and 267 have been synthesised and used as catalysts in asymmetric reductions of ketones with diborane. Mannich-type cyclisation reactions of 5-amino-3-benzylthio-4-cyano(ethoxycarbonyl)pyrazoles with dichlorophenylphosphine and aromatic aldehydes in the presence of cation exchange resin have been used to prepare a number of 6-oxo-6-phospha-4,5,6-trihydroimidazolo[l,2-b]pyrazoles, e.g. 268. Some of these compounds have herbicidal activity and this report is typical of a number of similar ones in the Chinese literature. A number of metallocycles, e.g. 269, have been reported as products from reactions of transient zirconocene-benzyne intermediates with phosphaimines followed by sulfuration or selenation. ... [Pg.134]


See other pages where Phospha-Mannich reaction is mentioned: [Pg.271]    [Pg.271]    [Pg.1423]    [Pg.1451]    [Pg.271]    [Pg.271]    [Pg.13]    [Pg.271]    [Pg.271]    [Pg.1423]    [Pg.1451]    [Pg.271]    [Pg.271]    [Pg.13]    [Pg.29]    [Pg.276]    [Pg.24]   
See also in sourсe #XX -- [ Pg.271 ]




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Mannich phospha

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