Aminophosphine/phosphinite

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... 

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]. 

Several efficient amidophosphine- and aminophosphine-phosphinite ligands have been reported by Agbossou and Carpentier.148,148a 148g Amidophosphine-phosphinite ligands (.9)-Cy.Cy-oxoProNOP and (.V)-Cp,Cp-oxoProNOP... 

If Q-symmetric ligands are employed in asymmetric hydrogenation instead of the corresponding C2-symmetric ligands, there coexist principally four stereoiso-meric substrate complexes, namely two pairs of each diastereomeric substrate complex. Furthermore, it has been shown that, for particular catalytic systems, intramolecular exchange processes between the diastereomeric substrate complexes should in principle be taken into account [57]. Finally, the possibility of non-estab-hshed pre-equilibria must be considered [58]. The consideration of four intermediates, with possible intramolecular equilibria and disturbed pre-equihbria, results in the reaction sequence shown in Scheme 10.3. This is an example of the asymmetric hydrogenation of dimethyl itaconate with a Rh-complex, which contains a Q-symmetrical aminophosphine phosphinite as the chiral ligand. 

Table 27.1 Enantiomeric hydrogenation using aminophosphine-phosphinites (AMPP). 

Scheme 33.4 One-step synthesis of aminophosphine phosphinite bidentate ligands.

Chiral ligands containing tervalent phosphorus acid derivatives as coordination sites continue to be explored for asymmetric metal catalysed reactions. New examples this year include the phosphite (119) and stereoisomers, the phosphites (120), 2 the diphosphinite TADDOP (121), the diphosphites (122) containing crown ethers, the aminophosphine-phosphinites AMPP s (123) and... 

Aminophosphines, phosphinites and phosphonites from quasi-phosphonium salts with alkyl halides in normal 5 n reactions. The aminophosphonium salts and the salts derived from aryl phosphinites and diaryl phosphonites are stable, but the majority of the quasi-phosphonium salts which contain alkoxy groups are dealkylated during the reaction with the alkyl halide (the Arbuzov reaction, see below). Thio analogues of phosphinites and... 

The hydrolysis of tervalent phosphorus acid derivatives with two P—C bonds leads to secondary phosphine oxides (50) and with one P—C bond to phosphonus acid derivatives (51). Chlorophosphines react rapidly with water, but aminophosphines, phosphinites and phosphonites often survive a short wash with aqueous NaHC03, an effective way to remove contaminating ammonium salts in the crude products. However, aminophosphines with small substituents, e.g. dimethylaminodimethylphosphine, aryl phosphinites and phosphonites and trimethylsilyl phosphinites and phosphonites are hydrolysed too quickly for such a treatment. The hydrolyses are catalysed by acids (the hydrolyses of phosphinites and phosphonites are also catalysed by OH ) and are much faster than hydrolyses of the corresponding phosphoryl compounds [up to a factor of 10 for acid-catalysed hydrolysis of (MeO)3P compared with (MeO)3P=0 ]. Dialkyl phosphonites are rapidly hydrolysed to the monoalkyl esters (51, X = OR) in weakly acidic water, whereas hydrolyses to phosphonous acids require reflux with strong acid or base, e.g. equation 131 Bis-(dialkylamino) phosphines may also be partially hydrolysed to phosphonous acid amides (51, X = NR2). Tervalent phosphorus acid derivatives with hydrogen sulphide give secondary phosphine sulphides or phosphonodithious acids, e.g. equation 156 . ... 

Fogassy, G., Tangier, A., Levai, A. (2003) Enantioselective hydrogenation of exocyclic alpha,beta-unsaturated ketones. Part 111. Hydrogenation with Pd in the presence of cinchonidine, y. Mol. Catal. A. Chem. 192, 189-194. Hapiat, F., Agboussou, F., Mortreux, A. (1994) Synthesis of new chiral arene Ru(ll) aminophosphine-phosphinite complexes and use in asymmetric hydrogenation of an activated keto compounds. Tetrahedron Asymm. 5, 515-518. 

Carpentier, J.F., Agboussou, F., Mortreux, A. (1995) Catalytic asymmetric hydrogenation of activated keto-compounds in some homogeneous and silica supported di(4-carboxylato)aminophosphine-phosphinite)diRhodium... 

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