Phenols dialkylation

Polyesters hexabromophthalic anhydride, tetrabromodienes, pentabromo-phenol, dialkyl tetrabromophthalate, organophosphate plasticizers, most of the inorganic fillers. 

Zinc dialkyl dithiophosphates are the primary oxidation inhibitors in combining these functions with antiwear properties in automotive oils and high pressure hydrauhc fluids. Their production volume is followed by aromatic amines, sulfurized olefins, and phenols (22). 

The intense reddish-brown color of the acetylacetone titanium complexes impart a yellow discoloration to white inks. This discoloration is accentuated when the inks are used to print substrates that contain phenol-based antioxidants. The phenoHc compounds react with the organic titanate to form a highly colored titanium phenolate. Replacement of 0.25 to 0.75 moles of acetylacetone with a malonic acid dialkyl ester, such as diethyl malonate, gives a titanium complex that maintains the performance advantages of the acetyl acetone titanium complexes, but which is only slightly yellow in color (505). These complexes still form highly colored titanium phenolates. 

Mixtures of a titanium complex of saturated diols, such as TYZOR OGT, and a titanium acylate, such as bis- -butyl-bis-caproic acid titanate, do not have a yellowing or discoloring effect on white inks used to print polyolefin surfaces (506). The complexes formed by the reaction of one or two moles of diethyl citrate with TYZOR TPT have an insignificant color on their own and do not generate color with phenol-based antioxidants (507). The complexes formed by the addition of a mixture of mono- and dialkyl phosphate esters to TYZOR TBT are also low color-generating, adhesion-promoting additives for use in printing polyolefin films (508). 

When used alone at low temperatures, diaLkyl thiodipropionates are rather weak antioxidants. However, synergistic mixtures with hindered phenols are highly effective at elevated temperatures and are used extensively to stabilize polyolefins, ABS, impact polystyrene (IPS), and other plastics. 

Formation of Ethers. Very high ether yields can be obtained from alcohols and phenols with dialkyl sulfates in CH2CI2 and concentrated NaOH—tetrabutylammonium chloride at room temperature or slightly elevated temperature within 1—5 h (18). Using excess aqueous caustic—N(C4H2)4HS04, unsymmetrical aUphatic ethers can be prepared with alkyl chlorides at 25—70°C in 3—4 h (19) (see Ethers). 

Monochlorophenols. Chlorination of phenol [108-95-2] between 50 and 120°C gives a ortho ratio of 1.65. To improve the selectivity in the paia position, it is possible to use dialkyl sulfides, diaiyl sulfides (12), oi alkyl and aiyl sulfides combined. Sulfides are active only at low tempeiatuies (<50 C), because at high tempeiatuies the active species decomposes into sulfui and chlorine. 

Dialkyl and alkyl aryl ethers can be cleaved with iodotrimethylsilane ROR -bMe3SiI — Rl-bMe3SiOR. A more convenient and less exjjensive alternative, which gives the same products, is a mixture of chlorotrimethylsilane and Nal. Alkyl aryl ethers can also be cleaved with Lil to give alkyl iodides and salts of phenols in a reaction similar to 10-73. Triphenyldibromophosphorane (Ph3PBr2) cleaves dialkyl ethers to give 2mol of alkyl bromide. ... 

The reaction with disubstituted formamides and phosphorus oxychloride, called the Vilsmeier or the Vilsmeier-Haack reaction,is the most common method for the formylation of aromatic rings. However, it is applicable only to active substrates, such as amines and phenols. An intramolecular version is also known.Aromatic hydrocarbons and heterocycles can also be formylated, but only if they are much more active than benzene (e.g., azulenes, ferrocenes). Though A-phenyl-A-methyl-formamide is a common reagent, other arylalkyl amides and dialkyl amides are also used. Phosgene (COCI2) has been used in place of POCI3. The reaction has also been carried out with other amides to give ketones (actually an example of 11-14),... 

In Formula 33 is pictured a completely mixed ester of a thiophosphate in which all groups are different. The thiophosphoryl chloride method was used for preparing such compounds. It was of interest to see whether or not other compounds could be prepared by the condensation of a dialkyl chlorothiophosphate with a phenol to give products such as shown in Formulas 34 to 36. 

Metal complexes, dialkyl thiophosphates and dialkyl thiocarbamates of Zn, Ni, Ba, and Ca, in particular, are widely used for the stabilization of lubricants [30-32,34]. At moderate temperatures (350 400 K), these inhibitors are less efficient than phenols, but they are more potent at higher temperatures (430 480 K). The sophisticated mechanism of action of these antioxidants involves their reactions with hydroperoxide. The interaction of hydroperoxide with metal dialkyl thiophosphates induces a cascade of reactions [5,66-69],... 

Monoarylation of l-amino-4-hydroxyanthraquinone (6.39 X = OH) results in violet dyes such as Cl Disperse Violet 27 (6.44 R = H) and the bluish violet Cl Disperse Blue 72 (6.44 R = CH3) the latter dye is also important as Cl Solvent Violet 13. Chlorination of 1,4-diaminoanthraquinone with sulphuryl chloride gives the 2,3-dichloro derivative (Cl Disperse Violet 28), which on condensation with phenol yields Cl Disperse Violet 26 (6.45). Monoaryl or dialkyl derivatives of 1,4-diaminoanthraquinone (6.19 Cl Disperse Violet 1) are blue. Typical examples include Cl Disperse Blue 19 (6.46) and Cl Disperse Blue 23 (6.47). 

As we have seen (pp. 50 et seq.) the reaction between phosphorus oxydichlorofluoride and alcohols, phenols and thiols, affords dialkyl, dicyctoalkyl, diaryl phosphorofluoridates and dialkyl phosphorodithiolates. In a Report1 to the Ministry of Supply on fluorophosphonates a description was given of a new type of nitrogen fluorophosphonate formed by the action of 4 mol. of aniline on 1 mol. of phosphorus oxydichlorofluoride, the fluorine atom being unaffected ... 

In other reactions also the OH-group of the phenols shows itself to be more reactive than that of the aliphatic alcohols. Phenols, but not alcohols, react easily with diazomethane. With other alkylating agents also, such as alkyl halides, and dialkyl sulphates, the phenols react even in aqueous alkaline solution whilst the alcohols do not react under such conditions. Benzoyl derivatives, most of which crystallise readily, are excellently adapted for the characterisation of phenols (Schotten-Baumann reaction). 

There are relatively few reports of phase-transfer catalysed syntheses of phenols from activated haloarenes using quaternary ammonium salts, presumably because of the instability of the ammonium salts under the reaction conditions. A patented procedure for the conversion of, for example, 2,6-dichloropyridine into 6-chloropyrid-2-one (98%) using aqueous sodium hydroxide in the presence of benzyl-triethylammonium chloride at 120-150°C has been filed [32], A possible route to the phenols, however, comes from the observed reaction of phenols with potassium carbonateipotassium hydrogen carbonate to yield the aryl carbonates (80-85%) using the procedure described for the preparation of dialkyl carbonates (3.3.13) [50]. 

The catalysed two-phase adaptation of the Atherton-Todd procedure is effective for the phosphorylation of primary alcohols and of phenols [6] to produce trialkyl phosphates and dialkyl aryl phosphates. Trialkyl phosphates have also be obtained in high yield (>75%) from the alkylation of preformed tctra-n-butylammonium di-/-butylphosphate [7], Subsequent cleavage of the /-butyl groups provide a simple synthesis of monoalkyl phosphates. 

The dialkyl phosphite (0.25 mmol) in CC14 (60 ml) is added dropwise with vigorous stirring at 20°C to aqueous NaOH (50%, 60 ml), TBA-Br (1.6 g, 5 mmol), and the alcohol or phenol (0.2 mmol) in CC14 (120 ml). The mixture is stirred for a further 3 h at 20°C and then diluted with CH2C1, (50 ml). The mixture is filtered and the organic phase is separated from the filtrate, washed with aqueous HC1 (2%, 25 ml) and HzO (2 x 25 ml), dried (MgS04), and evaporated to yield the phosphate. 

As to the origins of the major N compounds identified, it is possible that at least a portion of some of these compounds are pyrolysis products of amino acids, peptides, proteins, [18] and porphyrins (a component of chlorophyll), [19] or originate from the microbial decomposition of plant lignins and other phenolics in the presence of ammonia. [20] Of considerable interest are the identifications aromatic and aliphatic nitriles. Nitriles can be formed from amines with the loss of 2 H2, from amides with the loss of H20, and also by reacting n-alkanoic acid with NH3. [21] The detection of long-chain alkyl- and dialkyl-nitriles points to the presence in the soil or SOM of long-chain amines... 

A broad range of compounds can be O-alkylated with carbene complexes, including primary, secondary, and tertiary alcohols, phenols, enols, hemiaminals, hydroxylamines, carboxylic acids, dialkyl phosphates, etc. When either strongly acidic substrates [1214] and/or sensitive carbene precursors are used (e.g. aliphatic diazoalkanes [1215] or diazoketones) etherification can occur spontaneously without the need for any catalyst, or upon catalysis by Lewis acids [1216]. 

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