Methyl acetate salicylate

Carreira and co-workers reported novel Ti(lV) complexes 69 derived from Ti(0 Pr)4, tridentate ligands 67, and salicylic acids such as 68. The complexes serve as competent catalysts for the addition of the methyl acetate-derived silyl ketene acetal to a large range of aldehydes (Eqs. 8B2.16 and 8B2.17) [22]. The salient features of this system include the wide range of functionalized aliphatic and aromatic aldehydes that may be used the ability to carry out the reaction with 0.2-5 mol % catalyst-loading and experimental ease with which the process is executed (Table 8B2.8). Thus the reaction can be carried out at -10 to 0°C, in a variety of solvents, without recourse to slow addition of reagents. The adducts from the catalytic reaction were isolated with excellent enantiopurities up to 99% ee. The original catalyst-preparation... 

On the other hand, phosphorane intermediates are not expected to be involved in the hydrolysis of phosphate monoesters, so the effective observed catalysis by the carboxyl group of salicyl phosphate 3.21 [51] (Scheme 2.26) is presumed to be concerted vith nucleophilic attack. (The hydrolysis reaction involves the less abundant tautomer 3.22 of the dianion 3.21, and the acceleration is >10 -fold relative to the expected rate for the pH-independent hydrolysis of the phosphate monoester dianion of a phenol of pK 8.52.) However, this system differs from the methoxy-methyl acetals discussed above, in that there is a clear distinction between neutral nucleophiles, which react through an extended transition structure similar to 3.16 in Scheme 2.23, and anions, which do not react at a significant rate, presumably because of electrostatic repulsion. This distinction is well-established for the dianions of phosphate monoesters with good leaving groups (p-nitrophenyl [52] and... 

Salicylic acid is a bifunctional compound, containing both a hydroxyl group and a carboxyl group. The hydroxyl group contains a free pair of electrons which would allow salicylic acid to act as a nucleophile upon a positive source. Such positive sources include the carbonyl carbons of methyl acetate, acetic anhydride, and acetyl chloride. The hydroxyl group would attack the carbonyl carbon of acetic anhydride in the presence of an acid catalyst to give acetylsalicylic acid (aspirin), one of our desired products. The mechanism is as follows ... 

Nitro compounds, ar. Nitrobenzene, m-Dinitrobenzene o-Nitrophenol N-Nitramines Oxonium fluoroborate Trialky loxonium salt Trialky loxonium fluoroborate Pyrylium fluoroborate Carboxylic acid esters HCOOC Hs, p-Nitro-phenyl formate Isopropenyl acetate Salicylic acid esters Ethyl cyanoacetate Chloroformic acid esters Ethyl chloroformate, ClCOOC Hg-i Methyl trichloroacetate Diethyl oxalate Ethyl malonate... 

Benzyl butyrate Benzyl mercaptan L-Camphor Fenchyl alcohol Methyl acetate 2-Methyl-2-butanethiol Methyl hexyl ketone Methyl salicylate a-Pinene Pine (Pinus palustris) oil... 

Figure 35-L Lowering of the glass transition temperature. To of a poly(styrene) by various mass fractions, Ws, of plasticizers. From top to bottom iS-naphthyl salicylate, tricresyl phosphate, methyl salicylate, and methyl acetate (After G. Kanig.)...

Naphthyl salicylate + Phenyl salicylate 0 Tricresyl phosphate Methyl salicylate Nitrobenzene 0 Chloroform X Methyl acetate 4 Ethyl acetate A Carbon disulfide... 

V phenyl salicylate tricresyl phosphate o methyl salicylate Q nitrobenzene A chloroform X methyl acetate ethyl acetate ° benzene toluene... 

It appears that the only anion for which the pathway via the mixed acetic salicylic anhydride is important is that of 3,5-dinitroaspirin [83]. Here the rate enhancement is not large. The rate constant (2.68 x 10 min at 39°C is only 7.3 times greater than that for the hydrolysis of the methyl ester (6.65 x 10 x 55.5 = 3.69 x 10 min ) [83] the corresponding ratio for the hydrolysis of aspirin itself is 175 [77, 79]. Hydrolysis of the anion of 3,5-dinitroaspirin in oxygen-18-enriched water leads to 39 per cent incorporation of the label into the product, 3,5-dinitrosalicylic acid, and solvolysis in 50 per cent v/v aqueous methanol yields 60 per cent of methyl 3,5-dinitrosalicylate [83]. These results can be explained only if the reaction proceeds, at least partially, via the mixed anhydride 52. Three pieces of evidence... 

Bis(salicylic acids) have been polymerized with metal salts to yield the chelate polymers (lX-26). Metal acetylacetonates (72), and metal chlorides and acetates have been used. Aqueous (9, 99,131) or organic (72) media are suitable. Data indicating that high molecular weight products were obtained have not been presented. The insolubility of the products is the main reason. A comparative study of the polymerization of a free bis(salicylic acid), the corresponding bis(methyl salicylate), and the corresponding bis(methyl ether salicylic acid) has been reported (72). 

Figure 27 Glass transition temperatures of polystyrene solutions with various low molecular weight diluents , ) -naphthyl salicylate +, phenyl salicylate O, tricresyl phosphate 0 methyl salicylate nitrobenzene 0, chloroform x, methyl acetate , ethyl acetate , carbon disulfide , benzene toluene A, amyl butyrate (after ref. 181, as cited in ref. 57, with...

Methyl, ethyl, n-propyl, isopropyl, n-hutyl, benzyl, cyclohexyl esters of formic, acetic, oxalic, succinic, tartaric, citric, benzoic, salicylic (and other substituted benzoic acids), phthalic and cinnamic acids phenyl esters of acetic, benzoic and salicylic acids. 

As a general guide, however, it may be noted that the following have fairly easily recognisable odours methyl and ethyl formate methyl and ethyl acetate (apples) methyl and ethyl benzoate methyl salicylate (oil of winter-green) and ethyl salicylate methyl and ethyl cinnamate. (It is however usually impracticable to distinguish by odour alone between the methyl and ethyl esters of a particular acid.) Methyl and ethyl o. alate, and methyl and ethyl phthalate are almost odourless. Succinic and tartaric esters have faint odours. 

Choice of solvent for recrystallisation. Obtain small samples (about 0 5 g.) of the following compounds from the storeroom (i) salicylic acid, (Li) acetanilide, (iii) m-dinitrobenzene, (iv) naphthalene, and (v) p-toluene-sulphonamide. Use the following solvents distilled water, methylated spirit, rectified spirit, acetone, benzene and glacial acetic acid. 

Successful results have been obtained (Renfrew and Chaney, 1946) with ethyl formate methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, sec.-butyl and iso-amyl acetat ethyleneglycol diacetate ethyl monochloro- and trichloro-acetates methyl, n-propyl, n-octyl and n-dodecyl propionates ethyl butyrate n-butyl and n-amyl valerates ethyl laurate ethyl lactate ethyl acetoacetate diethyl carbonate dimethyl and diethyl oxalates diethyl malonate diethyl adipate di-n-butyl tartrate ethyl phenylacetate methyl and ethyl benzoates methyl and ethyl salicylates diethyl and di-n-butyl phthalates. The method fails for vinyl acetate, ieri.-butyl acetate, n-octadecyl propionate, ethyl and >i-butyl stearate, phenyl, benzyl- and guaicol-acetate, methyl and ethyl cinnamate, diethyl sulphate and ethyl p-aminobenzoate. 

Methyl benzoata, tnelbvl salicylate, benzyl acetate, benzyl benzoate, and Iren benzyl alcohol are present in small amounts, as well as methyl anthraniJale and oreosol in Iraoea. Tliicod has also recently identified lormic acid, and aatrol or iso-saliol. 

Some oils consist almost entirely of esters for example, those of Oaultheria procumhens and Betula lenta contain about 99 per cent, of methyl salicylate. Bergamot and lavender owe the greater part of their perfume value to esters of linalol, of which the acetate predominates. Geranium oil owes its fragrance chiefly to geranyl esters, of which the tiglate is the chief. On the other hand, oils such as spike lavender, sandalwood, lemon-grass, and citronella contain but small quantities of esters, and owe their perfume value to entirely different types of compounds. 

Salicylic acid reacts with acetic acid to produce acetylsalicylic acid the active ingredient in aspirin. It also reacts with methanol to form methyl salicylate, more commonly known as oil of wintergreen. 

Methanol, ethanol and 3-methylbutanol [1], acetaldehyde, trichloroacetaldehyde [2] and acetone [3] all ignite in contact with gaseous fluorine. Lactic acid, benzoic acid and salicylic acid ignite, while gallic acid becomes incandescent. Ethyl acetate and methyl borate ignite in fluorine [2],... 

The chemical structures of the majority of FMs that have been studied in wastewater treatment are given in Figs. 1-3. Figure 1 shows a variety of FM structures that include alcohols, aldehydes, and ketones, including benzyl acetate (phenylmethyl ester acetic acid), methyl salicylate (2-hydroxy-methyl ester benzoic acid), methyl dihydrojasmonate (3-oxo-2-pentyl-methyl ester cyclopentaneacetic acid), terpineol (4-trimethyl-3-cyclohexene-1-methanol), benzyl salicylate (2-hydroxy-phenylmethyl ester benzoic acid), isobornyl acetate... 

Primary+secondary removal benzyl acetate=86.4-99.9 methyl salicylate=92.0-99.9 methyl dihydrojasmonate=81.9-99.9 terpineol=95.4-99.9 benzyl salicylate=90.3-99.9 isobornyl acetate=84.5-99.9 g-methyl ionone=83.1-99.8 p-f-bucinal=84.8-99.3 hexylcinnamaldehyde=95.3-99.9 hexyl salicylate=96.4-99.9 OTNE=51.4-99.4 acetyl cedrene=71.3-99.9... 

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