Aminophosphinates

The aliphatic and aromatic aminophosphinic acids are weak acids. They exist presumably as zwitterions of structure (E3) rn+h2-ch-r ... 

A method for the synthesis of long-chain aminophosphinic acids having surface-active and antibacterial activity followed the procedure developed by Schmidt [182]. It is based on the condensation of the hypophosphite salt of a primary amine with an aldehyde or ketone [183], as shown in Eq. (108) ... 

TABLE 13 Surface-Active Properties of Sodium Salts of Aminophosphinic Acids... 

Agbossou E., Carpentier J. E. Hapiot E., Suisse I., Mortreux A. The Aminophos-phine-Phosphinites and Related Ligands Synthesis, Coordination Chemistry and Enantioselective Catalysis Coord. Chem. Rev. 1998 I78-I80 1615-1645 Keywords stereoselective Diels-Alder reaction catalysts, aminophosphine-phosphinites, enantioselective catalysts... 

Polymer supported xanthene derivatives have been used in the solid phase synthesis of 1-aminophosphinic acids, RCH(NH2)PH(0)0H, <%TL1647> and of C-terminal peptide amides <96JOC6326>. Xanthene units also feature in crown ethers <96JCS(P2)2091>, calixarenes <96JOC5670> and in a flexible template for a P-sheet nucleator <96JOC7408>. 

This chapter will also deal with compounds containing two or three phosphinous amide units, which, for simpUcity, will be named here as bis(amino-phosphanes) or tris(aminophosphanes) but not with phosphinous amides containing other additional organophosphorus functionaUties as, for instance, the so-called aminophosphine phosphinites (AMMP), which have been the subject of increasing attention in the Uterature dealing with catalytic asymmetric transformations and have been treated in other reviews [2,3]. 

Other chiral ligands such as BINAP (where BINAP is bis(diarylphosphino)-1,1 binaphthyl) or aminophosphines are also efficient for stereoselective synthesis of chiral-at-metal Ru complexes [39-41]. 

The various reactions of aminophosphines with ketones have been discussed. Reaction of (52) with benzaldehyde presumably takes place by attack at carbonyl carbon followed by a proton shift. " The same site of initial attack is suggested for the reaction of pyruvate esters with (53), although in this case it is followed by rearrangement. 

Aminophosphines and amidoximes are reported to form the phos-phoramide derivative (63) however, a similar reaction with amidoxime ethers gives the diazadiphosphetidine (64). ... 

The alcoholysis and transamination of various aminophosphines have been studied as functions of the basicity of the attacking nucleophile and the substituents on phosphorus. As might be expected the reaction is facilitated by electron-withdrawing groups on phosphorus. The hydrolysis of tris(dimethylamino)phosphine (90) to phosphorous acid has been investigated using thin-layer chromatography and the amides (91) and (92) have been identified as intermediates. 

Few examples of A-(phosphino)phosphazenes, RzP N=PRg, are known, but aminophosphines with P-perfluoroalkyl substituents have now been converted into A-phosphinophosphazenes by reaction with phosphoranes in the presence of triethylamine ... 

Using R = Ph, Y = S02CeH4Me or PS(OPh)2, the aminophosphine form was detected. A second mole of chlorophosphine was added and in all cases P-phosphinophosphazenes were obtained ... 

Mention has already been made of the aminophosphine -> phosphazene rearrangement (Section 2). It has been noted that some of these phos-phazenes, (31) and (32) [Y = SOj-CFs, SOj-CeHi-p-Me, P(0)Ph2, P(S)Ph2, or PS(OPh)2], exhibit significant differences in the magnitude... 

It has been foundthat the product of the following reaction sequence exists in the phosphazene (shown) rather than the aminophosphine form ... 

The n.m.r. spectra of these phosphazenes are straightforward when M = Ge or Sn, but when M = Si, two j/Vicow-methyl signals appeared at room temperature. A likely reason for this observation is that the rotation of the Si Meg group is hindered and that the rate of this rotation is slow on the n.m.r. time scale. A series of related derivatives was prepared in which the nature of the A-substituent determined whether the product was a phosphazene or aminophosphine ... 

Protonation studies of diphenylphosphinic esters and amides show that Ji>a H i creases upon protonation of the esters but that ypN< h decreases upon protonation of the amides.Values of JpN< ii have been tabulated for a number of compounds. The cyclic aminophosphine (79) has all four Jpxch constants with the same sign, probably positive. Attachment of the proton to an sp carbon atom, as in (80), does not enhance yi>Ncn in fact the reverse occurs. ... 

The i.r. spectra of two crystal forms of aminomethylphosphonic acid (91) and its and analogues have been studied. A Fermi resonance between vxh and vxd vibrations and certain binary combinations can explain most of the spectra. The related aminophosphinic acid (92) and... 

Various aminophosphines have also been found to catalyze coupling in the absence of copper. 

Nucleophilic Attack at Carbon.- The reactions of silyl-aminophosphines with carbon disulphide result in the formation of... 

A number of methylenebis(aminophosphines) (104) have been prepa-51... 

NP=CHSiMe3, with diethylamine provides the aminophosphine Me SiNH-PNEt2(Cf SiMe ) which in turn adds a second mole of dimethylamine to give the novel phosphorus(III)-phosphorus(v) derivative 7. 

Jpp = 41.5 Hz), respectively. In both cases the resonances are In chemical shift regions expected and characteristic of aminophosphines. 

The bidentate phosphine dppe (l,2-bis(diphenylphosphino)ethane) and the aminophosphine eddp (2-aminoethyl-diphenylphosphine) form mixed ligand (N, P, O) complexes such as Co(acac) (edpp)2 and Co(acac)(en)(dppe). A preference for trans N-Co-P and P-Co-P configurations over N-Co-N was found for the bis(edpp) complexes.925... 

Hence, chalcogenoamidophosphinic acids of general formula R2P(E)NHR (27) can be considered as dichalcogenophosphinic acids with one of the chalcogen atoms replaced by an amido group. These amido species are still normally referred to as acids due to their acidic amide protons. They are accessible from reaction of thiophosphinic chlorides and primary amines (Equation 43) or from reaction of aminophosphines with elemental chalcogen... 

The use of aminophosphines with rhodium(I) for catalytic hydrogenation was established some years ago, especially by Stem et at. (261 also... 

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