Diphosphonate

HONC fulminic acid H2P2H2OS diphosphonic acid... 

Bis(2-Chloroethyl) 2-Chloroethylphosphonate. The commercial product, Albright Wilson s Antiblaze 78, is a mixture having various related higher boiling diphosphonates. This product is made by the Arbuzov rearrangement of tris(2-chloroethyl) phosphite [140-08-9] ... 

The dimer of phosphonic acid, diphosphonic acid [36465-90-4] (pyrophosphoms acid), H4P2O3, is formed by the reaction of phosphoms trichloride and phosphonic acid in the ratio of 1 5. It is also formed by the thermal decomposition of phosphonic acid. Unlike the chemistry of phosphoric acid, thermal dehydration does not lead to polymers beyond the dimer extended dehydration leads to a disproportionation to condensed forms of phosphoric acid, such as [2466-09-3] and phosphine. 

Technetium-99m medronate ( Tc methylene diphosphonate) is used as a bone imaging agent to delineate areas of altered osteogenesis. The product is formed by the addition of up to 7.4 GBq (200 mCi) of Tc pertechnetate. 

Fig. 15. Diphosphonic acids used in self-assembled multilayer preparation.

Sca.Ie nd Sta.in Controllers. Polyacrjiates (low molecular weight) and organic phosphonates, eg, (l-hydroxyethyhdene)diphosphonic acid, prevent or control precipitation of CaCO by acting as chelating agents (qv) or dispersants (qv) to prevent excessive formation of hard scale by promoting crystal distortion. 

Fig. 1 A) Separation of phosphates and phosphonic acids B) absorption plots of track 5 and track 8. PjOl (1), PjOio (2), P20t (3), POl (4), mixture 1 (5), aminotrimethylene-phosphonic acid (6), l-hydroxyethane-l,l-diphosphonic acid (7), mixture II (8).

H4P2O5 (2)C > Diphosphonic acid (diphosphorous or pyrophosphorous acid)... 

Phosphonates, especially aminotri(methylenephosphonic acid) (ATMP) and l-hydroxyethylidene-l,l-diphosphonic acid (HEDP). Organophosphonates have the ability to control both scaling and corrosion by a combination of chelation and crystal nuclei growth supression (threshold) mechanisms they also provide scale control by crystal distortion. 

Phosphonates. Various phosphonates, such as 1-Hydroxyethylidine-l,l-diphosphonic acid (HEDP), have been... 

Aminotrimethanephosphonic acid is formed from formamide, acetamide, urea, or alkanenitriles with phosphorous acid [296]. By reaction of monoalkyl phosphite or P406 with glacial acetic acid or the corresponding anhydride ethane-1 -hydroxy-1,1-diphosphonic acid is formed after hydrolysis [297,298]. P406 can be obtained from P4 and 02 in a high yield of 85-90% [299]. 

Diphosphinomethane is a valuable intermediate to form methylene diphosphonic acid by oxidation with nitric acid (see Sec. IV). The alkali salts of methyl-enediphosphonic acid offer sequestering properties and are used as detergent builders. 

This reaction also takes place with halogenides of dibasic acids. Thus adipoyl chloride and diethyl phosphite are reacted at 90°C for 8 h yielding adipyl-diphosphonic acid diethyl ester, according to Eq. (41). 

Tetraphosphonate compounds are another type of calcium-sequestering agent and detergent builder. Propane 1,1,3,3-tetraphosphonate can be formed by reaction of the sodium carbanion of tetraisopropylmethylene-diphosphonate with dichloromethane, then hydrolyzed and converted to the wanted salt [97,98] see Eq. (54) ... 

Ethane-1-hydroxy-1,1-diphosphonic acid is a substance widely used as a sequestering agent. Hence there are many methods developed for its large-scale preparation [106,107]. The substance was known as early as 1865 [79]. 

One process to form ethane-1-hydroxy-1,1-diphosphonic acid is the treatment of acetic acid with phosphorus trioxide [124] see Eq. (67) ... 

There are many methods for the preparation of ethane-1-hydroxy-1,1-diphosphonic acid including reacting phosphorus trichloride and acetic acid in the presence of tributylamine [106], phosphorus with acetic acid and oxygen [108], acetic anhydride with phosphorous acid and acetyl chloride [80,84-86,109,110], and acetic anhydride with phosphoric acid and acetic acid [111]. By another method ketene and phosphorous acid can be used [112], as shown in Eq. (68) ... 

The diacetylated ethane-1-hydrox-1,1-diphosphonic acid is prepared by dissolving the diphosphonic acid in acetic acid and adding acetic anhydride [114]. The sodium salt can be directly converted to the free acid form by passing it through an hydrogen cation exchanger. The bicyclic dimer is prepared by basic hydrolysis of diacetylated cyclic dimer, as shown in Eq. (70) ... 

Alberti G (1996) Layered metal phosphonates and covalently pillared diphosphonates. In Comprehensive supramolecular chemistry, vol 7. Pergamon, New York, p 151... 

Small amounts of phosphonium complexone [1560] are sufficient to increase adhesion to the stratal rock. Table 18-4 illustrates an example for plugging solution with Portland cement and phosphonium complexone. Calcium chloride acts as a regulator of the setting time in the suggested composition. More precisely, phosphonium complexone stands for certain chelating phosphorous compounds (e.g., oxyethylidene diphosphonic acid, nitrilo-trimethyl phosphonic acid, sodium tripolyphosphate, or amiphol) [1540]. The mixture is applicable at low temperatures from 20° to 75° C. 

L. I. Ryabova, N. B. Savenok, N. A. Mariampolskij, L. M. Surova, and D. F. Kovalev. Plugging solution—contains Portland cement, aluminium oxychloride, water and phosphonium complexone in form of e.g., oxy-ethylidene diphosphonic acid. Patent SU 1802086-A, 1993. 

Isobutyl methylphosphonic acid, 2-(Diethylamino) ethanethiol, and P,P-diisobutyl dimethyl diphosphonate. 

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