Alkyl benzoates

In general, substituent frequencies in azoles are consistent with those characteristic of the same substituents in other classes of compounds. Some characteristic trends are found, and these have been used to measure electronic effects. Thus, for example, the frequencies of v C—0] in 3-, 4- and 5-alkoxycarbonylisoxazoles (cf. 100) are respectively 9-12, 2-8 and 17-18 cm higher than those of the corresponding alkyl benzoates, indicating the... 

Even alkyl benzoate esters give only a small amount of exchange imder basic hydrolysis conditions. This means that reversal of the hydroxide addition must be slow relative to the forward breakdown of the tetrahedral intermediate. ... 

Singer and co-workers have shown that benzoyl chloride reacts with ethers to give alkyl benzoates [33] in chloroaluminate(III) ionic liquids. This reaction results in... 

As first described by Krizan and Martin,6 the in situ trapping protocol, i.e., having the base and electrophile present in solution simultaneously, makes it possible to lithiate substrates that are not applicable in classical ortho-lithiation reactions.7 Later, Caron and Hawkins utilized the compatibility of lithium diisopropylamide and triisopropyl borate to synthesize arylboronic acid derivatives of bulky, electron deficient neopentyl benzoic acid esters.8 As this preparation illustrates, the use of lithium tetramethylpiperidide instead of lithium diisopropylamide broadens the scope of the reaction, and makes it possible to functionalize a simple alkyl benzoate.2... 

Application of a method for reducing benzaldehydes to the corresponding alcohols with a fourfold excess of the aluminate [1] to alkyl benzoates proved to be difficult to control and frequently dangerous [2],... 

Treatment of A-acyloxy-A-alkoxybenzamides 76a with dilute aqueous sodium hydroxide, at room temperature, resulted in the rapid formation of alkyl benzoates 67.40 A crossover experiment using A-acetoxy-A-butoxy-/ -chlorobenzamide 26e and A-acetoxy-A-benzyloxybenzamide 27a resulted in the exclusive formation of butyl / -chlorobenzoate (46%) and benzyl benzoate (43%) esters along with the hydrolysis products, / -chlorobenzoic acid and benzoic acid indicating that ester formation involves an intramolecular process. 

In addition to the methods listed in Org. Syn. Coll. Vol. 1, 200, may be added the formation of dibenzoylmethane when certain alkyl benzoates are treated with sodium ethoxide.1... 

A further illustration has appeared28 of the reactivity of simple a-keto-alkyldi-phenylphosphine oxides (31) towards addition reactions, as outlined in Scheme 5. In the same paper, alkylation of chloro(di-t-butyl)phosphine (32) by alkyl benzoates is described 28 see Chapter 3 for details. A similar acylation reaction of tetramethyl-diphosphine disulphide (33) has been described, although the acetylphosphine sulphide (34) was not isolated.29... 

As above, the log k values of the different types of compounds [alkanols (ROH), polycyclic aromatic hydrocarbons (PAH), alkyl benzenes (RB), and alkyl benzoates (ROB)] each demonstrated a linear relationship with their log P values and this relationship was observed with different ratios of acetonitrile and water. The experiment was then performed in eluents containing different organic modifiers and it was found that the behaviour of analytes containing different functional groups differed and the effect depended on the log P of the analyte. 

Chromatographic Behaviour of log P = 3 Compounds in Aqueous Tetrahydrofuran. For analytes whose log P = 3, in 40% aqueous THF the predicted log A values of the model alkanols (ROH), polycyclic hydrocarbons (PAH), alkyl-benzenes (RB), and alkyl benzoates (ROB) are 0.64, 0.77, 0.90, and 0.79, respectively. The polarity of 40% aqueous THF is 7.72. The same polarity can be obtained in 56% aqueous acetonitrile. As noted earlier, in aqueous aceto-... 

Example 1 Separation of an alkylbenzene and an alkyl benzoate. The logP values of butyl benzoate and isopropylbenzene are 3.74 and 3.52, respectively, from Table 4.1. The separation of these compounds in 50% aqueous acetonitrile therefore requires a high plate number column as the log k values will be nearly identical. The most suitable eluent is 40% aqueous THF. See compounds 9 and 19 in Figure 4.3B. 

Tajima, S. Azami, T. Shizuka, H. Tsu-chiya, T. An Investigation of the Mechanism of Single and Double Hydrogen Atom Transfer Reactions in Alkyl Benzoates by the Ortho Effect. Org. Mass Spectrom. 1979,14,499-502. 

Reduction of aryl esters.1 Alkyl benzoates are reduced to 1,4-dihydro compounds by sodium in THF NH3 if 1 2 equivalents of water is present before addition of the metal (equation I). The presence of water can be useful for reduction of other aromatic systems (equation II). 

This suggests that the hydrolysis of the ethyl ester involves the Aac1 mechanism, but that protonated isopropyl benzoate cleaves by alkyl-oxygen cleavage. A change in mechanism at this point would explain the order of reactivity towards hydrolysis of the various alkyl benzoates, observed by Kuhn18. 

Aqua, glycerin, cyclomethicone, dicaprylyl carbonate, ascorbic acid, butyrospermum parkii, alcohol cetearyl, octocrylene, glyceryl stearate, C12-15 alkyl-benzoate, cera microcristallina, tocopheryl acetate, vitis vinifera, PEG-40 stearate, sodium carbomer, paraffinum liquid-urn, tetrasodium iminodisucciunate, BHT, phenoxyethanol, methyl paraben, propyl paraben, diazolidinyl urea and parfum. 

Aqua, ammonium lactate, aluminium starch octenylsuccinate, C12-15 alkyl benzoate, isopropyl palmitate, polymethyl... 

Alkyl Benzoates. Reduction of benzaldehyde with four-fold excess of LiAlH4 may be dangerous.4... 

Alkyl benzoates were separated on a column packed with 5 pm Gromsil ODS-2 and 10% of 3 pm Gromsil Si using a isocratic elution with mixture of 2 mM borate D2O-CD3CN (20 80 v/v). No baseline separation was achieved in LC due to the high... 

Alkyl benzoates 40% Ethylacrylate, 50% methacrylic acid, 10% lauryl methacrylate (custom made polymer), 0-3.75 wt.% polymer concentration Acetonitrile-water (40 60) pH 11.3... 

The solubility of rare earth hydrides in organic solvents is increased by appropriate additives, too. For this purpose the hydrides are reacted with electron-donor ligands such as alkyl benzoates, alkyl propionates, alkyl tolu-ates, dialkylethers, cyclic ethers, alkylated amines, N,N -dimclhylacelamide, AT-methyl-2-pyrrolidone, trialkyl and triaryl phosphines, trialkyl phosphates and triaryl phosphates, trialkyl phosphates, hexamethylphosphoric triamide, dimethyl sulfoxide, etc. Prior to use as a polymerization catalyst the prereacted mixture of the rare earth hydride plus the additive is prereacted with Al-alkyl-based Lewis acids in the temperature range of 60-100 °C for 10 min to 24 h [351,352]. 

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