Tris- -phosphite

The importance of the polymeric form was pointed up in Fade-ometer and sunlamp tests where polyphosphites were found to be much more effective than mono (tris) phosphites derived from the same starting hydroquinones, especially when the compounds were used in conjunction with thiodipropionate esters. The data in Table IV show a comparison between a polyphosphite and a mono (tris) phosphite derived from the same substituted hydroquinone. A commonly used hindered phenolic was also tested in place of the phenolic phosphite for comparison. The protection against embrittlement obtained with the polymeric phenolic... 

The present paper describes several new classes of hindered phenyl bis- and tris-phosphites having di-benzo[d,f][1,3,2]dioxaphosphepin and dibenzo[d,g]-[1,3,2]dioxaphosphocin rings. The latter compounds exhibit superior effectiveness as processing stabilizers together with greater resistance to discoloration and hydrolysis. The di- and tri-alkanolamine esters are of particular interest because of their even greater resistance to hydrolysis at 50°C for extended time periods previously achievable only in the case of certain di-hindered phenyl phosphonites. 

The two classes of hindered substituted bis- and tris- phosphites having either (a) dibenzo[d,f][1,3,2]dioxaphosphepin or (b) dibenzo[d,g][1,2,3Jdioxaphosphocin rings were selected for study as processing stabilizers because their bicyclic structures promised stabilizers of increased thermal and hydrolytic stability compared to the acyclic hindered phenylphosphonites previously studied (1). 

It is apparent that of the compounds studied herein the hindered substituted bis- and tris-phosphites having dibenzofd,f][1,3,2] dioxaphosphepin rings, are the most effective compounds in the specific polyolefin substrates tested. Of particular interest in this regard is the triethanolamine tris-phosphite compound 8. 

With a large excess of trimethyl phosphite, the triphenylphosphine is replaced, forming acetyl[bis(trimethyl phosphite)]cobalt dicarbonyl. The bis- and tris(phosphite) derivatives of acetylcobalt tetracarbonyl are more thermally stable and more resistant to air oxidation than are the monophosphite or triphenylphosphine derivatives. 

Dimyristyl phosphite Dioctyl phosphite Diphenyl isooctyl phosphite Diphenyl phosphite Heptakis (dipropylene glycol) tri phosphite... 

Several cationic q -alkenyl-complexes obtained by protonation or deuteria-tion of tris(phosphite)iron q -diene complexes have been studied by nmr spectroscopy (Ittel et ai, 1979). The structures are octahedral, coordinated with phosphite ligands at three of the sites. The q -alkenyl group occupies two sites and a hydrogen atom which is adjacent to the alkenyl-group fills the sixth site giving a noble gas (18-electron) configuration at the iron centre. 

Di-isopropyl hydrogen phosphite is a colourless mobile liquid, which, unlike triethyl and tri-isopropyl phosphite, is completely miscible with water, due undoubtedly to the polar P=0 group. 

Peroxide-decomposing antioxidants destroy hydroperoxides, the sources of free radicals in polymers. Phosphites and thioesters such as tris(nonylphenyl) phosphite, distearyl pentaerythritol diphosphite, and dialkyl thiodipropionates are examples of peroxide-decomposing antioxidants. 

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 initial hydroformylation is conducted using tris(2,4-di-/-butylphenyl)phosphite (5) as ligand. 

Esterification. Alkylphenols react with acid chlorides and acids to produce commercially important esters. Three equivalents of -nonylphenol (10) react with phosphoms trichloride or tributyl phosphite to produce tris(4-nonylphenyl) phosphite (TNPP) (11). 

The use of 4-nonylphenol ia the production of tris(4-nonylphenyl) phosphite is also not expected to show much growth because of its replacement ia many polymers by higher performing and more hydrolytically stable phosphites. 

The primary use for 2,4-di-/ f2 -butylphenol is in the production of substituted triaryl phosphites. 2,4-Di-/ f2 -butylphenol reacts with phosphoms trichloride typically using a trialkylamine or quaternary ammonium salt as the catalyst. Hydrogen chloride is formed and either complexed with the amine or Hberated as free hydrogen chloride gas forming the phosphite ester, tris(2,4-di-/ f2 -butylphenyl)phosphite [31570-04-4] (58). The phosphite-based on... 

The hydrolysis of phosphites is retarded by the addition of a small amount of a base such as triethanolamine. A more effective approach is the use of hindered phenols for esterification. Relatively good resistance to hydrolysis is shown by two esters derived from hindered phenols tris(2,4-di-/ / butylphenyl)phosphite [31570-04-4] (25) and tetrakis(2,4-di-/ /f-butylphenyl)4,4 -biphenylenediphosphonite [38613-77-3] (26). The hindered fluorophosphite [118337-09-0] (27) has excellent resistance to hydrolysis. 

These polymers are subjected to high temperatures, ca 300°C, duting extmsion and iajection molding. Processing stabilizers are used to decrease both the change ia viscosity of the polymer melt and the development of color. A phosphite, such as tris(2,4-di-/ f2 -butyiphenyi)phosphite (25) or bis(2,4-di-/ f2 butyiphenyi)pentaerythritol diphosphite [26741-53-7] ia combination with a phenoHc antioxidant such as octadecyl... 

Virtually all of the organo derivatives of CA are produced by reactions characteristic of a cycHc imide, wherein isocyanurate nitrogen (frequendy as the anion) nucleophilically attacks a positively polarized carbon of the second reactant. Cyanuric acid and ethylene oxide react neady quantitatively at 100°C to form tris(2-hydroxyethyl)isocyanurate [839-90-7] (THEIC) (48—52). Substitution of propylene oxide yields the hydroxypropyl analogue (48,49). At elevated temperatures (- 200° C). CA and alkylene oxides react in inert solvent to give A/-hydroxyalkyloxazohdones in approximately 70% yield (53). Alternatively, THEIC can be prepared by reaction of CA and 2-chloroethanol in aqueous caustic (52). THEIC can react further via its hydroxyl fiinctionahty to form esters, ethers, urethanes, phosphites, etc (54). Reaction of CA with epichlorohydrin in alkaline dioxane solution gives... 

Because nitrile rubber is an unsaturated copolymer it is sensitive to oxidative attack and addition of an antioxidant is necessary. The most common practice is to add an emulsion or dispersion of antioxidant or stabilizer to the latex before coagulation. This is sometimes done batchwise to the latex in the blend tank, and sometimes is added continuously to the latex as it is pumped toward further processing. PhenoHc, amine, and organic phosphite materials are used. Examples are di-Z fZ-butylcatechol, octylated diphenylamine, and tris(nonylphenyl) phosphite [26523-78-4]. All are meant to protect the product from oxidation during drying at elevated temperature and during storage until final use. Most mbber processors add additional antioxidant to their compounds when the NBR is mixed with fillers and curatives in order to extend the life of the final mbber part. 

Phosphites Tris-(p-nonylphenyl) phosphite (X) No Widely used in conjunction with conventional stabilisers (q.v.) in PVC. Some types appear to be useful heat and light stabilisers in polyolefins. Function primarily as peroxide decomposers rather than chain-breaking antioxidants. 

In addition to stabilisers, antioxidants and ultra-violent absorbers may also be added to PVC compounds. Amongst antioxidants, trisnonyl phenyl phosphite, mentioned previously, is interesting in that it appears to have additional functions such as a solubiliser or chelator for PVC insoluble metal chlorides formed by reaction of PVC degradation products with metal stabilisers. Since oxidation is both a degradation reaction in its own right and may also accelerate the rate of dehydrochlorination, the use of antioxidants can be beneficial. In addition to the phenyl phosphites, hindered phenols such as octadecyl 3-(3,5-di-tcrt-butyl-4-hydroxyphenyI)propionate and 2,4,6-tris (2,5-di-rcrt-butyl-4-hydroxybenzyl)-1,3,5-trimethylbenzene may be used. 

The reduction of keto steroids by treatment with chloroiridic acid, or sodium chloroiridate, and trimethyl phosphite has been studied in some detail.Ketones at the 2- and 3-positions are reduced predominantly to the corresponding axial alcohols, while ketones at 4,6,7,11,12,17 and 20 are not affected. The rate of reaction is increased by addition of aqueous sodium hydroxide. Replacement of sodium chloroiridate by tris(triphenylphos-phine)rhodium chloride gives a system which reduces a 3-keto steroid to the... 

Cleavage of this group is achieved with tetramethylguanidinium syn-2-pyridinecarboxaldoxime. Tris(hexafluoro-2-propyl) phosphites are sufficiently reactive to undergo transesterification with alcohols in a stepwise fashion. ... 

The ethoxycarbonyl group was developed for the protection of phosphonates. The derivative is prepared by reaction of tris(trimethylsilyl) phosphite with ethyl chloroformate and can be cleaved by hydrolysis of the ester followed by silyla-tion with bistrimethylsilylacetamide. ... 

Tlie desulfurization of thiono compounds is another frequently used synthetic approach for the formation of double bonds via carbenoid intermediates. By this methodology, some indigoid 1,3,5,7-tetraazafulvalenes 88 and 90 were synthesized (83BSB781 90JPR949).Tliis dimerization starting from 2,4,5-tris(dimethylamino)imidazolium chloride via the appropriate thione 87 has been realized in the presence of phosphanes or phosphites to... 

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