Phosphinic acid derivatives

The yielded product can be converted to a surface-active compound if at least one ester group has been transformed to the free acid or an alkali metal salt thereof [160]. There are also many compounds from phosphinic acid derivatives claimed to be useful as sequestrants and builders to improve detergency, especially bisphosphonylmethylphosphinic acids and polyphosphinic acids [structures (9) and (10)], respectively ... 

Another reaction for synthesizing phosphinic acid derivatives was described by Jungermann and coworkers [173-176], It is based on the reaction of olefins with phosphorus trichloride in the presence of a Friedel-Crafts catalyst, according to Eq. (106) ... 

The following nitrogen containing phosphinic acid derivatives have been proposed as chelating and wetting agents [184]. They were prepared from chloromethylphosphinic acid with the appropriate amines see Eq. (Ill) ... 

C. Reactions of Phosphoric and Phosphinic Acid Derivatives.—The optically active phosphinate ester (90) has been shown to react with benzyl Grignard reagents or lithium anilide with inversion of configuration. Oxidation of... 

A modification of this procedure allowed the isolation of 1,3,2-oxazaphospholidine 52a as a single diastereomer [41] and its application to asymmetric synthesis of enantiomerically and diastereomerically pure phosphinic acid derivatives 53 and 54 and tertiary phosphine oxides 55 (Scheme 20) [45], A few years later, a similar approach for the synthesis of enantiomerically pure tertiary phosphine oxides 55... 

Scheme 20 Synthesis of diastereomerically pure phosphinic acid derivatives 53...

Reactions of Phosphonic and Phosphinic Acid Derivatives.—The reactions of phos-phonic and thiophosphonic amides and chlorides with carboxylic acid chlorides and amides have been discussed.101 Dialkyl alkylphosphonates and alkyl dialkylphos-phinates may be used for the iV-alkylation of imidazoles, triazoles, and pyrroles.105... 

The surface tensions of some fatty-acid phosphates have been determined228 and the surfactant properties of perfluoroalkanesulphonamidoalkanephosphonic acid and corresponding phosphinic acid derivatives studied.229... 

The biological properties of phosphorus amino acid analogues (and their derivatives) depend upon their stereochemistry. Consequently, numerous methods for obtaining these compounds in stereochemically pure form have been developed. Two excellent review articles summarize the work performed prior to 1993. 3,4 Resolution of racemates continues to be a useful approach for obtaining optically pure aminoalkylphosphonic and -phosphinic acid derivatives (vide infra), but most of the newer literature describes asymmetric syntheses of these compounds.15-17 Two methods for resolution and one for asymmetric synthesis are described (vide infra) they have been selected since they are relatively easy to perform, work with a variety of side chains, can be carried out on a reasonable scale with readily available starting materials, and produce products of high stereopurity. However, just as in traditional amino acid chemistry, each side chain introduces its own complications, and in many cases, especially for more complex analogues, other methods may be preferred. 

Compounds containing phosphorus can be both valuable synthetic intermediates and target compounds of solid-phase synthesis. Important synthetic intermediates include phosphonium salts and phosphorus ylides, which are key intermediates in carbonyl olefinations. Their preparation is discussed in Section 5.2.2.1. The preparation of oligonucleotides, these being the most important phosphorus-containing target molecules in solid-phase synthesis, is considered in Section 16.2. In this chapter, the preparation of phosphines, phosphonic acid derivatives, and phosphinic acid derivatives is discussed. 

Phosphinic acid derivatives, Phosphonic acid derivatives, Phosphoric acid derivatives... 

Fig. 31. Phosphonic and phosphinic acid derivatives of cyclen (top), and tetraamide derivatives (bottom).

The dimers of phosphinic acid derivatives are one of the strongest HB complexes found in gas phase [134—137]. The chirality of the phosphinic acids relies on the presence of two nonidentical substituents on the phosphorus atom and the position of the hydrogen bonded to one of the two oxygens linked to the phosphorus. The chiral recognition in the minimum and proton transfer transition state structures of fifteen pairs of chiral phosphinic acid dimers (Scheme 3.24) has been carried out using DFT and MP2 methods, up to MP2/6-311++G(3df,2p) level [30]. 

The four-coordinate phosphorus(V) nitrogen compounds are extremely numerous and detailed data about phosphonic and phosphinic acid derivatives and others can be found in the handbook literature. 

Tertiary phosphine oxides and sulfides are also produced by way of the Michaelis-Arbuzov reaction beginning with phosphonous esters [R2POR ] and thiophosphonous esters [R2PSR ], when used in reaction with haloalkanes (see Section 3.5). Similarly, phosphine oxides are formed from trivalent phosphorus reagents in the Michaelis-Becker reaction as well as the conjugate addition reactions of phosphinous acid derivatives with a, -unsaturated compounds (see Section 3.5). 

Several mixed anhydride methods have, therefore, been developed. The acid is coupled to a second acid moiety that is considered to be disposable. This strategy relies fully on the regioselectivity of the aminolysis where the reactive center a is more reactive than b (see Fig. 6). The concept of mixed anhydrides has been extended to carbonic, boric, iso-ureas, phosphoric, and phosphinic acid-derived species. Iso-ureas and phosphorous-containing reagents will be discussed in separate articles. 

General catalytic hydrophosphinylation reaction of alkenes and alkynes with hypophosphorous compounds (385) to give H-phosphinic acid derivatives (386) has been described. Compounds (386) are important biologically active compounds as well as being synthetic intermediates which can be converted into a variety of other organophosphorus compounds using well-established procedures. ... 

The use of (1-1ithioalkyl)phosphonlc or -phosphinic acid derivatives allows considerable modifications to be made in the preparation of a wide variety of structural types. Interaction of... 

Ph), or phosphonic amides (97 R = NMe2 or MC HgO) with sodium in dioxane, or with magnesium activated by anthracene in THF, affords the bis(2-hydroxyaryl)phosphinic acid derivative (or phosphine oxide) (98) following a carbanionic rearrangement. 

CGP 35348 is a phosphinic acid derivative, a (GABAb) GABA receptor ANTAGONIST. It is used as a pharmacological tool, and shows ANTICONVULSANT / ANTIEPILEPTIC properties in animal models. 

The formation of the phosphinic acid derivative (32) by treatment of benzylbis-(a-hydroxybenzyl)phosphine oxide (33) with alkali is also suggested to occur via a three-membered ring, In this case, an intramolecular 1,2-hydride shift is proposed to occur as the intermediate ring is broken (see Scheme 7). 

Moskva, V.V., Maikova, A.L, and Razumov, A.L, Phosphinic and phosphinous acid derivatives. Part 58. Reaction of ortho esters of carboxylic acids and acetals with phosphorus(in) acid chlorides, Zh. Obshch. Khim., 39, 595, 1969 Chem. Abstr, 71, 50076r, 1969. 

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