Tert-butyl formate

Attention has been given to possible adverse effects of incorporating tert-butyl methyl ether into antomobile fuels. tert-Butyl formate is an established product of photolysis, and it has been shown that photolysis in the presence of NO can produce the relatively stable tert-butoxyformyl peroxynitrate. This has a stability comparable to that of peroxy-acetyl nitrate, and may therefore increase the potential for disseminating NO (Kirchner et al. 1997). 

Chemical/Physical. tert-Butyl formate undergoes hydrolysis yielding ferf-butyl alcohol in stoichiometric amounts. At 22 °C, the estimated hydrolysis half-lives at pH 7 and pH 11 are 5 d and 8 min, respectively (Church et al, 1999). 

Chemical/Physical. Ultrasonic irradiation (205-1078 kHz) of methyl tert-butyl ether (100 mM) in water in the presence of ozone maintained at 23 °C yielded tert-butyl formate and tert-butyl alcohol (Kang et al., 1999). The highest reaction rates occurred at 358 and 618 kHz. The combination of ozone and ultrasonic irradiation was more effective in degrading methyl tert-butyl ether than ultrasound and ozone alone. The investigators concluded that the combination of ozone and ultrasound irradiation was most effective at a frequency of 358 kHz. The rate of degradation of methyl tert-hniyX ether was not affected in the presence of natural organic matter. 

Condensation of cyclobutanones with ferf-butoxybis(dimethylammo)methane gave the a-enamino ketones,56 while bicyclo[3.2.0]hept-2-en-6-onc condensed with tert-butyl formate using sodium hydride in dimethoxyethane.186 Experimental details were not given. 

P 13.5 Assessing the Hydrolysis Half-Life of tert-Butyl Formate... 

Methyl formate Ethyl formate. n-Propyl formate iso-Propyl formate. n-Butyl formate iso-Butyl formate sec.-Butyl formate. tert.-Butyl formate. n-Amyl-formate iso-Amyl formate n-Hexyl formate cycfoPentyl formate. cycioHexyl formate Allyl formate. ... 

It is well known that esters are planar and that the Z form is much more stable (=3 kcal/mol) than the E form (4). The form is of course observed in small ring lactones but as soon as the size of the lactone ring allows the Z form to exist, the E form is no longer observed (5). Even in the case of tert-butyl formate, where there must be a strong steric repulsion... 

Tert-butyl formate ester (CH3)3COCHO Products 0.41 ">... 

Onstein P, Stefan MI, Bolton JR (1999) Competition Kinetics Method for the Determination of Rate Constants for the Reaction of Hydroxyl Radicals with Organic Pollutants Using the UV/H2O2 Advanced Oxidation Technology The Rate Constants for the tert-Butyl Formate Ester and 2,4-Di-nitrophenol,/. Adv. Oxid. Technol. 4, No. 2 231-236. 

C5H10O2 tert-butyl formate 762-75-4 -17.15 1.0826 2 5781 C5H12CI3N bis(2-chloroethyl)methylamine 55-86-7 25.00 1.1788 2... 

C5H10O2 tert-butyl formate 762-75-4 206.73 7.343 2 5845 C5H120 ethyl propyl ether 628-32-0 145.65 8.390 1... 

C5H10O2 tert-butyl formate 762-75-4 16.422 117.152 1,2 5842 C5H120 methyl isobutyl ether 625-44-5 15.081 121.586 1,2... 

In the formate esters, the free energy difference decreases from esters to thioesters and amides for the methyl and tert-butyl groups, and E-methyl formate is only observed in very small amounts (<0.3%) at low temperature (190 K), as shown by 13C NMR spectroscopy [3], The energy is significantly lower for the bulky tert-butyl moiety relative to the methyl group and this seems to be a function of steric hindrance since ethyl formate and iso-propyl formate have intermediary values [4,5]. In the tert-butyl formate, a strong electronic repulsion accounts for the relatively high proportion of E isomer (10%). 

POB Propane oxidizing bacterium PPR Porous pot reactor SBF Submerged biofilter SBR Sequencing batch reactor TAA tert-amyl alcohol TAME tert-amyl methyl ether TBA tert-butyl alcohol TBF tert-butyl formate TBM tert-butoxy-methanol... 

As reduction products in laboratory tests, tert-butyl-ether (TBA) and tert butyl formate (TBF) could be proven, whereby TBF is converted rapidly to TBA. CO2 remains at the end of the TBA decay [7]. The fact that TBA can also be a primary component of gasolines (within the %-range) makes it often difficult to interpret the degradation path under field conditions. 

The primary function of methyl tert-butyl ether (MTBE) as an additive in gasoline is to enhance the octane level of unleaded gasoline. By virtue of the oxygen atom it contains, it increases the oxygen-to-fuel ratio in gasoline. It has also been shown that adding MTBE results in lower emissions of carbon monoxide and hydrocarbon as well as polycychc aromatic hydrocarbons (PAHs). MTBE oxidation, initiated by hydroxyl radicals, can yield a number of products such as tert-butyl formate, formaldehyde, methyl acetate, and acetone, depending on the pathway. 

The products of the reaction of OH with ETBE in the presence of NO c have been investigated by Wallington and Japar (1991) and Smith et al. (1992), The major product observed in both studies was tert-butyl formate, with yields of 76 6% and 64 3% reported, respectively. Smith et al. (1992) also observed formaldehyde (molar yield 53 4%), tert-butyl acetate (13 1%), ethyl acetate (4.3 0.3%), acetaldehyde (16 1%), and acetone (1.9 0.2%). 

On the basis of the data of Thiault and Mellouki (2006) for the OH reaction, and data presented earlier for other vinyl ethers, the tropospheric lifetimes of isobutyl and tert-butyl vinyl ethers will likely be quite short (< 1 h under most conditions), and will be controlled by reaction with NO3, OH, and O3. Major end products of the OH-, O3-, and NO3-initiated oxidation will be CH2O and either isobutyl or tert-butyl formate. 

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