Phosphines with carboxyl groups

Phosphines with carboxylic groups were some of the earliest water-soluble phosphines investigated [26]. The group of Podlahova prepared a diphosphine, the phosphine analog of ethylenediaminetetraacetic acid, which is obtained as a monohydrate of the tetrasodium salt (18) [26]. Jegorov and Podlahova recently published a short review on the catalytic uses of these carboxyalkylphosphines [27]. 

Phosphines with carboxylic groups were some of the earliest water-soluble phosphines investigated (see also p. 70) [87]. The Podlahova s group prepared a... 

A styrene/divinylbenzene copolymer was phosphorylated and converted to a polymer with phenylphosphinic acid groups 41 [114] (see Experiment 5-9, Section 5.4). Ion-exchange coordination to Cu(II), Cd(II), Ni(II), Zn(II) and Eu(III) was studied. Resins with carboxylic groups in the a- and P-positions display higher metal ion uptake than those with -COOH in the y-position. Macroporous polymers 42 with a functional group based on triisobutyl-phosphine sulfide have been synthesized and characterized for the selective adsorption of Au(III) and Pd(II) [115]. 

Despite many clinical similarities, these agents differ in their absorption, dosing with other drugs, and duration of actions for example, quinapril has a of 3 hours whereas ramipril has a of 13-17 hours. The quest for ACE inhibitors devoid of the sulfhydryl group also led to the evaluation of phosphonate-containing inhibitors, on the basis of the notion that phosphinic acid is bioisosterically equivalent to sulfhydryl and carboxylate groups in terms of Zn " chelation. This lead to the development of fosinopril... 

The enantioselective syntheses of carbanucleosides (e.g., 80) have also been reported where the key step is the enantioselective allylic amination of 78 with a nucleobase (here 79) (Eq. 7) [168]. A chiral phosphine bearing a carboxyl group has also been shown to be effective for this class of substrate [169]. 

Hydrogenation reactions that are efficiently controlled by chiral Rh-phosphine catalysts involve those carbon-carbon double bonds substituted with carboxylic and amide groups. They are precursors of a-amino acids, compounds that are very important protein building blocks. The best substrate is (Z)-a-acetamidocinnamic acid 10 ... 

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