Dimethoxy Toluene

For Hammett correlations for rate constants of substituted benzenes reacting with hydroxyl radicals under experimental conditions of pH 9, the elementary hydroxyl radical rate constants (l/m sec 108) containing toluene, dimethoxy-benzene, benzene, and nitrobenzene correlate with aresonance as follows ... 

Zinc enolates can be prepared in solvents of greatly different polarity, including THF, DME, Et20, 1,4-dioxane, benzene, toluene, dimethoxy-methane, DMF, B(OMe)3, DMSO, and mixtures thereof, just to mention the most frequently used ones.1-3 Reformatsky reactions in the absence of a solvent have also been described.7 The reagent is dimeric in the crystal state and in solution except for the most polar media.5,8... 

The position of the free hydroxyl group in these two alkaloids is either C or C , since Spath has shown that the OiV-diacetyl derivative of -5-hydroxy-3 4-dimethoxyphenylethylamine, when heated in toluene solution with phosphoric oxide, yields a product which must be either 6-acetoxy-7 8-dimethoxy-, or 8-acetoxy-6 7-dimethoxy-l-methyl-3 4-dihydrowoquinoline. On reduction with tin and hydrochloric acid t is converted into anhalonidine, which must therefore be 6-hydroxy-7 8-dimethoxy- (or 8-hydroxy-6 7-dimethoxy-)-l-methyl-l 2 3 4-tetrahydrofsoquinoline. Similarly the methiodide of the acetoxy-com-pound on reduction yields, by loss of acetic acid and addition of two hydrogen atoms, pellotine, proving the latter to be A -methylanhalonidine. The position of the free hydroxyl group was finally shown by Spath to... 

A solution of 1.3 equiv of alkyllithium in hexane is added to a mixture of 1 cquiv of the enimine and 1.4equiv of (1 R,2R)-l,2-dimethoxy-1,2-diphenylethane8 in toluene at — 78°C. The solution is stirred at either — 78 CC or — 45 °C (see table above) for 1 -13 h and then treated with an acetate buffer (pH 4.5) for 12 h. The usual workup gives the aldehyde, which is then reduced with NaBH4 in methanol to give the alcohol. 

When carba-a-DL-galactopyranose (6) reacts with a, a-dimethoxy-toluene, there are obtained two stereoisomers, 69 and 70, whose structures... 

For example, 3-isopropyl-7a-methyl-5-oxo-perhydropyrrolo[2,l-A]oxazole 244 formed by condensation of (A)-vali-nol 243 and 2-(2,3-dimethoxy-5-methylphenyl)-4-oxopentanoic acid 242 in toluene was the key intermediate in the total synthesis of (-)-mastigophorene B 245 (Scheme 35) <1999JA2762>. 

To a two-neck 50 mL round-bottom flask was added 6,7-dimethoxy-l-methyl-l,2,3,4-tetrahydroisoquinoline (3.093 g, 14.92 mmol), C. rugosa lipase (1.5 g, 1410 units/mg), pentamethylcyclopentadienyliridium(III) iodide (34.3 mg, 0.030 mmol) and toluene saturated with water (25 mL), resulting in an orange solution containing some insoluble amine. 

The system Ru2(OAc) Cl/O2/toluene/50°C oxidisedR CH NHR to imines R CH=NR converted 1,2,3,4-tetrahydroisoquinoline to the 3,4-dihydroisoquinoline with isoquinoline, and 6,7-dimethoxy-l,2,3,4-tetrahydroisoquinoline to 6,7-dimethoxy-3,4-dihydro-iso-qninoline (cf. mech. Ch. 1) [18], Such oxidations were also catalysed by TPAP/NMO/PMS/CH3CN, e.g. the conversion of indoline to indole (in which indoline nndergoes a donble-bond shift and aromatisation), and the oxidation of 1,2,3,4-tetrahydroqninoline to 3,4-dihydroquinoline (Fig. 5.1, Table 5.1) [19]. 

Over recent years, the electrochlorination of a wide range of substrates has been reported. The direct halogenation of benzene has been studied at Pt and Rh electrodes and the in situ spectro-electrochemical monitoring of the process with confocal microprobe Raman methods allowed optimization of the reaction conditions [80]. Toluene has been chlorinated at DSAs and the kinetics of this process have been explored in detail [81]. The electrochlorination of 1,4-dimethoxy-2-tert-butylbenzene has been reported in CCI4 and in acetonitrile environments [82]. A difference in mechanism has been proposed to explain the observation of l,4-dimethoxy-2-tert-butyl-5-chlorobenzene and l,4-dimethoxy-2-tert-butyl-6-chlorobenzene, respectively, as the main products. Succinimide is electrochlo-rinated to give A -chlorosuccinimide at platinum electrodes, but the process has been reported to be relatively inefficient due to side reactions (when compared... 

Dimethoxy toluene and derivs 5 D1305 dinitrodimethoxytoluer.es 5 D1305 mononitrodimethoxytoluenes 5 D1305 trinitrodimethoxytoluenes 5 D1305... 

A second, less well-known example is the anodic conversion of toluenes in methanol as solvent to benzaldehyde-dimethoxy acetals (180, 7S7) ... 

By conducting further experiments in different solvents, such as acetone, isopropanol, ethanol, and toluene, it was found that application of APS from an aqueous solution gave the best results. Extensive experimentation with the polymeric dimethoxy- and trimethoxysilanes, PS076.5 and PS076 respectively, gave similar results. Representative data for PS076.5 are shown in Table 2. Application from 0.5 wt% solutions in water produced the maximum IFSS and retention after exposure to 1 h boiling in water. 

The synthesis of 2C-T-17 R required starting with the S isomer of secondary butanol. The S 2-butanol in petroleum ether gave the lithium salt with butyllithium which was treated with tosyl chloride (freshly crystallized from naphtha, hexane washed, used in toluene solution) and the solvent was removed. The addition of 2,5-dimethoxythiophenol, anhydrous potassium carbonate, and DMF produced S 2,5-dimethoxyphenyl s-butyl sulfide. The conversion to R 2,5-dimethoxy-4-(s-butyl-thio)benzaldehyde (which melted at 78-79 °C compared to 86-87 °C for the racemic counterpart) and its conversion in turn to the nitro-styrene, S -2,5-dimethoxy-4-(s)-butylthio-B-nitrostyrene which melted at 70-71 °C compared to 68-69 °C for the racemic counterpart, followed the specific recipes above. The preparation of the intermediates to 2C-T-17 S follows the above precisely, but starting with R 2-butanol instead. And it is at these nitrostyrene stages that this project stands at the moment. 

A suspension of 4 g of trans-2-(2,5-dimethoxy-4-methylphenyl)-cyclopropanecarboxylic acid in an equal volume of H20, was treated with sufficient acetone to effect complete solution. This was cooled to 0 °C and there was added, first, 2.0 g triethylamine in 35 mL acetone, followed by the slow addition of 2.5 g ethyl chloroformate in 10 mL acetone. This was stirred for 0.5 h, and then there was added a solution of 1.7 g NaN i in 6 mL If20, dropwise. After 1 h stirring at 0 °C, the mixture was quenched by pouring into H20 at 0 °C. The separated oil was extracted with EtzO, and extracts dried with anhydrous MgS04. Removal of the solvent under vacuum gave a residue of the azide, which was dissolved in 10 mL anhydrous toluene. This solution was heated on the steam bath until the nitrogen evolution was complete, and the removal of the solvent under vacuum gave a residue of crude isocyanate as an amber oil. This intermediate isocyanate was... 

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