Oxidative 2-methyl-

Pyridin-, Chinolin- und N,N-Dimethyl-anilin-N-oxid werden elektrolytisch an Queck-silber in Methanol/Tetramethylammoniumchlorid zu Pyridin (81% d.Th.), Chinolin (78% d.Th.) bzw. N,N-Dimethyl-anilin (78% d.Th.) (galvanostat. bei 5 A/65°C) redu-ziert1. Analog verhalten sich 2- und 4-Methyl-pyridin-N-oxide (2-Methyl-pyridin 96% 4-Meihyl-pyridin 80% d.Th.)1. 

Methyl-3-propyl-2( 17/)-quinoxalinone 4-oxide 2-Methyl-3-propylthioquinoxaline 2-Methyl-3-(prop-2-ynyl)quinoxaline 2-Methyl-5-quinoxalinamine... 

Photolytic. Methyl vinyl ketone and methacrolein were reported as major photooxidation products for the reaction of 2-methyl-l,3-butadiene with OH radicals. Formaldehyde, nitrogen dioxide, nitric oxide, and HO2 were reported as minor products (Lloyd et al, 1983). Synthetic air containing gaseous nitrous acid and exposed to artificial sunlight (X = 300-450 nm) photo-oxidized 2-methyl-1,3-butadiene into formaldehyde, methyl nitrate, peroxyacetal nitrate, and a compound tentatively identified as methyl vinyl ketone (Cox et al, 1980). 

Methyl-4-pentanone, see 4-Methyl-2-pentanone 2-Methylpentene, see 2-Methyl-l-pentene 4-Methyl-4-pentene, see 2-Methyl-l-pentene 2-Methyl-2-pentenone-4, see Mesityl oxide 2-Methyl-2-penten-4-one, see Mesityl oxide... 

Linalool oxide, 2-methyl-2-vinyl-5-(Q -hydroxyisopropyl)tetrahydrofuran... 

A dehydrated linalool oxide, 2-methyl-2-vinyl-5-isopropenyltetrahydrofuran [13679-86-2], occurs naturally it has a minty eucalyptol odor and is used in perfumery. 

The oxidation of indoles and pyrroles by Fe(III) ions is less predictable than other chemical oxidations. 2-Methyl- and 3-methyl-indoles, respectively, yield (187) and (188), and whilst pyrroles may form pyrrole black , the rate of oxidation of pyrrole and of 1-methylpyrrole appears to be relatively slow. C-Alkyl and electron-donating substituents enhance the formation of oligimers, e.g. (189) -> (190) and (191) -> (192), and although electron-withdrawing substituents reduce the susceptibility of the pyrrole ring to oxidation, acyl- and alkoxycarbonyl-pyrroles of the type (193) are readily oxidized to the thermochromic dimer (194), which is in equilibrium with the dimer (195) via the monomeric pyrrolyl radical (72BCJ3584). 

Methyl-3-phenyl-2-pyrazinamine 1-oxide 2- Methyl-3 -phenylpyrazine... 

Methyl-5-phenylpyrazine 1,4-dioxide 2-Methyl-6-phenylpyrazine 1,4-dioxide 2-Methyl-3-phenylpyrazine 1-oxide 2-Methyl-3-phenylpyrazine 4-oxide 2-Methyl-5-phenylpyrazine 1-oxide 2-Methyl-5-phenylpyrazine 4-oxide... 

B-Methallyldiisopinocampheylborane (4), This reagent (4), prepared by reaction of ( + )-B-methoxydiisopinocampheylborane with methallyllithium, reacts with aldehydes to give, after oxidation, 2-methyl-1-alkene-4-ob (5) with >90% ee. 

Oxid), 1412 (NH - N-oxid) 3H-Pyrrol-l-oxid 2-Methyl-4,5-dihydro- E14b, 146 (aus N02-Keton) Pyrrolidin... 

Oxathian-3-oxid 2-Methyl-4-propyl- E14/1, 829 (S-oxid-Bild.)... 

Or, we oxidize (-)-2-methyl-l-butanol with potassium permanganate, obtain the acid 2-methylbutanoic acid, and find that this rotates light to the right. Again, no bond to the chiral center is broken, and we assign configuration V to ( + )-2-methylbutanoic acid. 

After the addition of MOXL the solution in DMF was refluxed for 36 hrs, and the resulting polymer was isolated and purified by precipitation from chloroform to diethyl ether. According to H-NMR spectroscopy the product contained 66—83 mol % of units derived from MOXL. The claim that block copolymer was formed was based on solubility data. Recently, similar results have been reported for the styrene oxide/2-methyl-2-oxyzoline system 106). 

Biimidazole (3). 2,2 -Bi(2-imidazoline) (1) can be oxidized to 2,2 -biimidazole (3) by conversion to the bistrimethylsilyl derivative (2), which is soluble in organic solvents, and oxidation of (2) in CCI4 with the activated manganese dioxide of Goldman (2, 257). The procedure can also be used to oxidize 2-methyl-2-imidazoline to 2-methylimidazole (67% overall yield). ... 

Unsaturated aldehydes and ketones can be selectively hydrogenated to the corresponding saturated carbonyl however, it is difficult to reduce the ethylenic group without also attacking the carbonyl group, although such a reduction may be achieved for certain compounds such as mesityl oxide (2-methyl-pentene-2-one-4) using a platinum catalyst at room temperature. 

SeleniumflV) oxide, a milder oxidizing agent compared to potassium permanganate, oxidized 2-methyl-IPs 86, 612, 613 to 2-formyl-IPs 614-616 in high yields. 

Paternostre, L., Damman, P, Dosiere, M. Polymorphism and crystal morphology of poly (ethylene oxide)-2-methyl resorcinol supramolecular complexes. Macromolecules, 32,153-161 (1999). 

III-E-21. Benzene Oxide (Oxepin) and Toluene-1,2-Oxide (2-Methyl Oxepin)... 

For toluene-l,2-oxide/2-methyl oxepin, photolysis and OH reaction are again competing daytime losses (Klotz et al., 20(X)). The OH reaction is calculated to occur on a timescale of about 0.5 h, while the photolysis lifetime is about 40 min. with overhead Sun. Products of the OH-initiated oxidation are the E, E- and , Z- isomers of 6-oxohepta-2,4-dienal, analogous to the 2,4-hexadiendial products of the benzene oxide/oxepin case. The main photolysis product identified was o-cresol, albeit only in about 10% yield. The reaction with NO3 is also very rapid, and should this species be present at nighttime, its removal via reaction with NO3 would be expected to occur in less than 1 min. in heavily polluted conditions. 

Figure IX-L-3. Estimated photolysis frequencies for the photodecomposition (disappearance) of benzene oxide/oxepin (R = H heavy curve) and toluene oxide/2-methyl oxepin (R = CH3 light curve) at 0.5 km altitude as a function of solar zenith angle using the measured value of yXCsHfiOf/jXNO ) = (4.41 0.44) x 10 and j(CH3C6H50)/jr(N02) = (3.99 0.48) x together with 7(N02) values as calculated for clear tropospheric skies at an altitude of 0.5 km and with an overhead ozone column of 350 DU.

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