Carboxylated phosphines

Keywords. Primary phosphines, Thioether phosphines, Amido phosphines, Carboxylate phosphines, Functionalized phosphines... 

Rhodium catalysts modified with carboxylated phosphines 45 (Table 3 n=5, n=7)229 and phosphonium phosphines 103 (Table 5 n=2,3,6,10)255 form very active catalytic systems for the hydrogenation of olefins in aqueous/organic two phase systems. 

Isomerization of allylbenzene and l-octene-3-ol catalysed by various metals (Rh, Ru, Ir) modified with tppts, tppms and the carboxylated phosphines, depicted in Table 3, 41 (n=2), 42 (n=0,l,2) and 43 as well as with 100 (Table... 

Other less commonly used coupling reagents include EEDQ (formation of mixed carboxylic carbonic anhydrides), Bop-Cl (formation of mixed carboxylic phosphinic anhydrides [52,53]), DPPA (formation of acyl azides), DECP (formation of acyl cyanides), MSNT (formation of mixed carboxylic sulfonic anhydrides), and benzisoxazo-lium salts (generation of phenyl esters [54]). 

Concerning the oxygen-containing bidentate ligands [R E02+ ] and MC, discrete dimeric, tetrameric and hexameric ring assemblies have been reported for organotin carboxylate, phosphinate, phosphonate monoester, phosphate diester, " sulfonate, and tungstate derivatives. 

Another example using palladium as the metal center involves the use of a carboxylic phosphine, which was effective in the intra- and intermolecular Heck reaction of a dimethyliodo derivative and of iodobenzene, respectively, with ethyl acrylate [23], For the intramolecular reaction, the cyclic amide was produced in nearly quantitative yields using mild reaction conditions (Eq. 9). A comparison with the TPPTS system reveals the m-TPPTC (m-triphenylphosphine tricarboxylic acid [ Li salt]) analog to be a more efficient system. After one hour of reaction, a 60% conversion was observed compared to approximately 45% with the TPPTS system. 

Carboxylated phosphine complex 3 is active for the cyanation, though this hydrophilic complex is inferior to 2 as a counter-PTC. As the cyanide anion is easily extractable, a phosphine complex having an ammonium group or a crown ether, which is insoluble in water [27], is also efficient for the cyanation. The catalytic efficiency is higher than that of the mixed system of lipophilic catalyst and normal... 

Figure 9 Regiospecific attack of carboxylic-phosphinic anhydrides depending on the nature of the nucleophile.

Regiospecific nucleophilysis is exhibited by carboxylic-phosphinic anhydrides RCOOPOR2. Thus, alcoholysis occurs by attack at P and aminolysis at C (3). 

Further work of the same group was focused on the obtention of P-ste-reogenic p-aminophosphine boranes. To this end, they employed a-formylated and a-carboxylated phosphine boranes (Scheme 5.18). 

Dependent upon the conditions, 1, T-dilithioferrocene or lithioferrocene may be obtained in tetramethylethylenediamine. Lithioferrocene and 1, I -dilithioferrocene are utilized for the preparation of various ferrocene derivatives [schemes (9.142) and (9.143)]. Lithioferrocenes, mercurioferrocenes, and derivatives of ferrocene containing various functional groups such as amines, carboxyls, phosphines, etc. are utilized for the... 

Unlike snlfonated phosphines, which retain water solubility at any pH of the reaction mixture, carboxylated phosphines can be used only in alkahne solutions. 

A(a)<- by stereoelection the polymerization of the racemic monomer R,S) gives a predominant R oi S polymer polypropylene oxide polypropylene sulfide poly-a-aminoacid A -carboxylic acid anhydride (initiator, aluminum alkyl, Ni carboxylate phosphine). A(b) by stereoelection one enantiomer of racemic mixture polymerises more easily than the other one racemic a-olefin B Chromatography of poly-racemic RRS/SSR oiRR/SS) just some examples are known (not separation but more exactly enrichment)... 

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