Methyltetrahydrofuran 2-MeTHF

Cyclopentyl methyl ether (CPME) is another alternative to typical ethereal solvents such as diethyl ether, THF, DME and dioxane. At present it is not bio-sourced but it is mentioned here as it has many advantageous properties as a direct replacement for ethers. Most importantly, the rate of peroxide formation is very slow and therefore, CPME is green in terms of risk avoidance and other criteria. Its use in a range of classical and modern synthetic procedures has been reported.  

2-MeTHF has also been used as an alternative to dichloromethane in biphasic reactions including alkylations, amidations and nucleophilic substitutions. For example, 2-nitrophenyl phenyl ether was prepared in 95% yield using 2-MeTHF as the organic solvent through reaction of phenol and o-fluoronitrobenzene using tetrabutylammonium bromide as a phase transfer catalyst. 

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By far more is known about the UV spectra of silylene-Lewis base complexes in matrices as well as in solution. To observe silylene-Lewis base complexes in matrices, an appropriate silylene precursor, in most cases a cyclic or acyclic oligosilane, is photolyzed at low temperature in an inert hydrocarbon or noble gas matrix, which is doped with small amounts (2-5%) of the respective Lewis base. In a few cases, 2-methyltetrahydrofuran (2-MeTHF), which serves as matrix material as well as a Lewis base, is used. When a rigid matrix such as a 3-methylpentane (3-MP) or 2-MeTHF matrix is used, the formation of the silylene complexes normally requires the matrix to be annealed in order to allow the molecules to diffuse through the softening matrix. In contrast, when the silylene is generated in an a priori soft matrix,... 

Certain cyclic ethers which will not homopolymerize will copolymerize with THF (25, 52). These cyclic ethers are stable five and six-membered ring compounds such as 2-methyltetrahydrofuran (2-MeTHF), and 1,4-dioxane (DOX). It is probable that 4-phenyl-l,3-dioxane (PhDOX), tetrahydropyran (THP), and 4-methyl-l,3-dioxolane (MDOL) which do not homopolymerize but which have been reported to copolymerize with BCMO (107, 108) would also copolymerize with THF. In the copolymerizations a correlation was again found between the basicity of the attacking ether and its reactivity with the cyclic oxonium ion. The... 

In contrast to the photoirradiation of a purified PhCN solution of Acr+-Mes at 298 K, when the photoirradiation of the same solution was performed at low temperatures (213-243 K) with a 1000-W high-pressure mercury lamp through the UV light-cutting filter (>390 nm) and the sample was cooled to 77 K, the color of the frozen sample at 77 K was clearly changed from green to brownish, as shown in the inset in Fig. 13.20. When a glassy 2-methyltetrahydrofuran (2-MeTHF) is employed for the photoirradiation of Acr+-Mes at low temperature,... 

NMR speetroseopie studies of Li- N labeled lithium hexamethyldisilazide in solvents ineluding THF, 2-methyltetrahydrofuran (2-MeTHF), 2,2-dimethyltetrahydrofuran (2,2-Me2THF), diethyl ether (Et20), t-butyl methyl ether (Bu OMe), n-butyl methyl ether (Bu OMe), tetra-hydropyran (THP), methyl i-propyl ether (Pr OMe), and trimethylene oxide (oxetane) have been used to eharaeterize the nature of the solvated speeies. Mono-, di-, and mixed-solvated dimers ean be identified in the limit of slow solvent exehange, but ligand exehange is too fast to observe... 

In solutions or in frozen matrices the effect of the environment is not negligible any more. The NIR spectra of Cgg were measured in various frozen noble gas matrices [34] and or T)sd distortions were found. The result was the same in the apolar methylcyclohexane matrix, while the distortion was H2h in the polar 2-methyltetrahydrofuran (2-MeTHF) matrix [35]. One might expect the same polarity dependence in solutions, but electrochemically generated Cgg ions showed a... 

Methyltetrahydrofuran (2-MeTHF) is an inexpensive solvent that is immiscible with water by substituting 2-MeTHF forTHF, work-ups may be eased. 

In a related study it was shown that mesityl-substituted trisilanes photolyzed in 2-methyltetrahydrofuran (2-MeTHF) as solvent formed silylenes which were stabilized by coordination with the ether-oxygen (equation 98). Insertion of the silylene into the ether C-O bond occurred in part as the glass was warmed155. 

Methyltetrahydrofuran (2-MeTHF, Aldrich) was distilled under nitrogen and subjected to column chromatography on neutral alumina immediately before use. The polymer whose spectrum is displayed in Figure 1 was prepared from a PVC sample (Nordforsk S-54) that has been described previously (12). 

Pace V, Hoyos P, Castoldi L, Dominguez de Maria P, Alcantara AR (2012) 2-Methyltetrahydrofuran (2-MeTHF) a biomass-derived solvent with broad application in organic chemistry. ChemSusChem 5 1369-1379... 

Another example of a successful renewable solvent that is not a fermentation product is 2-methyltetrahydrofuran (2-MeTHF). It is commercially synthesised by the acid mediated dehydration of hemicellulose into furfural, which is followed by a hydrogenation. Although similar to tetrahydrofuran (THF), the most obvious candidate for substitution by 2-MeTHF, it is a distinct molecule made by a process that has no equivalent downstream of the oil refinery where THF originates. Peroxide formation issues are unresolved, but 2-MeTHF does have advantages over THF. 2-Methyltetrahydrofuran is less water soluble than THF, and the achievable concentration of organometallic substrates is greater in 2-MeTHF than it is in THF. ... 

Pentacarbonyliron catalyzes the [4 -F 1]-cycloaddition of CO to allenyl ketones and allenyl aldehydes in high yields and with good stereoselectivity. This reaction was examined in 2-methyltetrahydrofuran (2-MeTHF) matrices where the substituted complex Fe(CO)4(2-MeTHF) was found to be produced upon photolysis of Fe(CO)s at 190-230 K. When Fe(CO)s was photolyzed at 230 K in 2-MeTHF in the presence of 5-methyl-3,4-hexadien-2-one and CO, the corresponding a-alkylidene butenolide was obtained (Scheme 4). The reaction proceeded via a dissociative process from Fe(CO)4(2-MeTHF). ... 

Methyl tert-butylhydroquinone, 20 105 Methyl-tertiary-butyl ether. See Methyl-tert-butyl ether (MTBE) Methyltestosterone, registered for use in aquaculture in Australia, 3 222t Nb-Methyl tetrahydrofolic acid, 25 802 2-Methyltetrahydrofuran (METHF),... 

Substituents on the porphyrin ring were omitted. Tetrahydrofuran (THF) was used as a model continuum dielectric for methyltetrahydrofuran (MeTHF). 

Regioselective acylation of cordycepin with vinyl acetate catalyzed by Novozym 435 in 2-methyltetrahydrofuran (MeTHF) [21]. 

Abbreviations DMSO, dimethylsulfoxide DMF, dimethyl formamide NMP, N-methylpyrrolidone MIBK, methyl isobutyl ketone DME, 1,2-dimethoxyethane iPrOAc also known as IPAc THF, tetrahydrofuran 2-MeTHF, 2-methyltetrahydrofuran MTBE, methyl t-butyl ether NA, not available. 

Abbreviations Agg. = aggregates AcrCN = acrylonitrile DMF = V,V-dimethylformamide DMSO = dimeth-ylsulfoxide EC = ethylene carbonate HC02Et = ethyl formate Me2CO = acetone MeCN = acetonitrile MeCOsMe = methyl acetate MeTHF = 2-methyltetrahydrofuran PC = propylene carbonate THF = tetrahy-drofuran THP = tetrahydropyran. 

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