Tributyl phosphite

The raw precious metal concentrate is totally dissolved in hydrochloric acid—chlorine solution to form the soluble chloride ions of each of the metals. Silver remains as insoluble silver chloride and can be filtered off. Gold, in the form of [AuClJ, is extracted with, eg, tributyl phosphite or methyl isobutyl ketone. Base metals are also extracted in this step, and are removed from the organic phase by scmbbing with dilute hydrochloric acid (HCl). Iron powder is then used to reduce the gold species and recover them from the organic phase. 

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). 

Tribromopropane Tributylamine Tributyl borate Tributyl phosphate Tributyl phosphite Trichloroacetaldehyde... 

Into a 3-L three-neck round-bottom flask equipped with a thermometer, a KPG stirrer and a 20-cm Vigreux column linked to a distillation apparatus with three cooled traps (MeOH/dry ice) were placed rw-4.5-(thiocarbonyldioxy)spiro[2.3]hexane (50 98.2 g, 0.63 mol) and freshly distilled tributyl phosphite (472 g, 1.89 mol). The mixture was heated at 115 120 0C/17 Torr for 44 h. The condensed distillates in the traps were combined, dried over 4 A molecular sieves and fractionally distilled through a 40-cm Vigreux column to give the product 51 yield 40 g (80%) bp 66.5 nC (760 Torr). 

Effect of Additives. One of the first attempts to solve the preignition problem by additives was the use of tributyl phosphite, claimed in a patent by Campbell (14) This compound inhibited the catalytic activity of lead compounds in promoting the glowing of carbon. A later patent issued to Withrow claimed that trimethyl phosphate and trimethyl phosphite also are effective as fuel additives in inhibiting surface ignition due to leaded deposits (94). Street, in 1952, ran tests with tricresyl phosphate as an additive in leaded fuel and reported that the phosphorus compound affected the occurrence of lead compounds in the end-gas region of the combustion chamber (80). 

Triazine 4-oxide (10 mmol) and triethyl phosphite (tributyl phosphite) (0.2 mol) were heated with stirring to reflux. The V-oxide dissolved and the solution became yellow. The mixture was evaporated to dryness in vacuo and the residue purified by column chromatography on silica gel with Et20 or EtOAc. 

A direct comparison of the additive behavior of neutral phosphates and phosphites in the four-ball test under relatively mild conditions is reported in the work of Goldblatt and Appeldoorn [43]. The data shown in Table 11-15 are their findings for 3% of the additive dissolved in a heavy white oil and run in the four-ball machine for 15 minutes at 1200 rpm. In wet air all the phosphates show about the same wear im.provement under a 10 kg load over wear with the base oil in dry argon there is no significant improvement. Tributyl phosphite functions consistently poorer in the wear test than either triallyl or triphenyl phosphite, whose behavior is not significantly different from that of the corresponding phosphates. All the additives improve the performance of the... 

Figure 11-8. Comparison of phosphate and phosphite triesters as additives. Additives in solvent-refined mineral oil. Four-ball test 60 seconds at 1500 rpm. 1 Tributyl phosphate, 120 kg. 2 Tricresyl phosphate, 120 kg. 3 Tricresyl phosphate, 100 kg. 4 Tributyl phosphate, 100 kg. 5 Trixylenyl phosphate, 120 kg. 6 Trixylenyl phosphate, 100 kg. 7 Tributyl phosphite, 140 kg. 8 Tributyl phosphite, 120 kg. 9 Tributyl phosphite, 100 kg. Data by W. Davey [45].

Pyrylium salts undergo some interesting reactions for example, addition of methoxide ion, which may occur at C-2 or C-4, according to the structure of the substrate. The rates of some of these reactions in buffers have been measured spectrophotometrically and the behaviour of the salts has been explained in electronic and structural terms. 2,6-Diphenylpyrylium perchlorate reacts with tributyl phosphite (by an Arbuzov rearrangement) to give a high yield of the phosphite (71). °... 

The reactions of bis(phosphoryl) disulphides with a variety of tervalent phosphorus acid derivatives or triphenylphosphine have been studied by means of low-temperature n.m.r. Intermediates were detected which indicated initial attack on one sulphur atom followed by substitution reactions at one of the phosphorus atoms, Arbuzov dealkylations, or phosphorane formation. An example is shown for the reaction of tributyl phosphite with bis(diethoxyphosphoryl) disulphide (25). In order to obtain solely thiophosphate products it is necessary to use bis(thiophosphoryl) disulphides, and one such compound (26) has been proposed as a highly effective reagent for the oxidation of oligonucleoside phosphites to phosphorothioates. A comparison of the efficiency of (26) with that of four other sulphurizing agents for use in... 

Triisopropyl Phosphite Tributyl Phosphite Triisooctyl Phosphite Tris(2- thylbexyl) Phosphite... 

Phosphorous acid, tributyl ester. See Tributyl phosphite... 

Syn-O-Ad P-312. See Tributyl phosphite Syn-O-Ad P-316. See Dibutyl phosphite Syn-O-Ad P-374. See Trioctyl phosphite Syn-O-Ad P-399. See Triphenyl phosphite Syn-O-Ad P-412. See 2-Ethylhexyl phosphate Syn-O-Ad P-415. See Amyl acid phosphate Syn-O-Ad P-417. See Butyl acid phosphate Synox 5LT. See 2,2 -Methylenebis (6-t-butyl-4-methylphenol)... 

TBIC. See t-Butyl peroxyisopropyl carbonate TBNPA. SeeTribromoneopentyl alcohol TBP TBP. See Tributyl phosphate TBPA. See Tetrabromophthalic anhydride TBPAE. SeeTribromophenyl allyl ether TBP-HP. See Tributyl phosphite TBPMI. SeeTribromophenyl maleimide... 

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