2-Nitro-3,5,6-trimethyl

Dmitro-4-oxy-l -propyl-benzol 6 1 249. Nitro-trimethyl-chinitn aus Pseudo ... 

That some modification to the position so far described might be necessary was indicated by some experiments of Nesmeyanov and his co-workers. Amongst other compounds they nitrated phenyl trimethyl ammonium and triphenyloxonium tetrafluoroborates with mixed acid the former gave 96 % of m- and 4 % of -nitro compound (88 % total yield), whilst the latter gave 80% of the tri-(p-nitrophenyl)oxonium salt. Ridd and his co-workers have made a quantitative study of the phenyl trimethyl ammonium ion. Their results, and those of other recent workers on the nitration of several cations, are collected in table 9.3. 

Chroman, 4-(p-hydroxyphenyl)-2,2,4-trimethyl-X-ray studies, 3, 622 Chroman, 2-methoxy-synthesis, 3, 806 Chroman, 5-methoxy-synthesis, 3, 778 Chroman, 7-methoxy-synthesis, 3, 778 Chroman, 8-methoxy-acylation, 3, 732 Chroman, 2-methoxy-2-methyl-synthesis, 3, 780 Chroman, 2-methyl-synthesis, 3, 785 Chroman, 5-methyl-reactivity, 3, 732 Chroman, 6-nitro-synthesis, 3, 784 Chroman, 4-phenyl-synthesis, 3, 783 Chroman, thio-metabolism, 1, 241 Chroman, 5,6-thio-2-substituted... 

Imidazole, 1,2,5-trimethyl-4-nitro-mass spectra, 5, 359 Imidazole, 1 -trimethylsilyl-reactions, S, 454... 

Quinolizinium salts, 2,4,6-trimethyl-condensation reactions, 2, 539 Quinolizinones reactions, 2, 544 synthesis, 2, 567 Quinolizinones, nitro-synthesis, 2, 568 Quinolizin-4-ones nitration, 2, 529 synthesis, 2, 565 2,2 -Quinolyl... 

Gas chromatographic analysis of the crude mixture (SE-30 on Chromosorb W, 1 m., 150°) showed the presence of some low-boiling materials (including unreacted methyl nitroacetate) and a significant amount of the doubly alkylated by-product, trimethyl 2-nitro-l,2,3-propanetricarboxylate. 

Benzaldehyde, o nitro, 46,81 Benzaldehyde, 2,4,6-trimethyl-, 47,1 Benzaldehydes, halogen- and methyl-substituted, preparation from diazomum salts and formal doxime, 46, IS... 

Kabanov et al.131) found that a copolymer of 4-vinylpyridine and acroleinoxime, 82 (PPox), is a powerful catalyst for the hydrolyses of PNPA, NABA, and 3-nitro-4-trimethyl-acetoxybenzoic acid 83 (NTBA). The activity of the copolymer was 103 times higher than that of the low-molecular-weight oxime, iso-butyraldoxime. They proposed the cooperative activation of the oxime- and pyridine-groups in the vicinity of pyridinium cation groups of the copolymer. 

Di azido-6-n itro-mesity lene (2,4-Di azido-6-nitro-1,3,5-trimethyl benzene). C9H9 02 N7, mw... 

With Pd(dba)2 in acetone/dichloromethane (1 1) and ethene (6-8 atm), styrene is formed from benzenediazonium tetrafluoroborate in 51% yield with seven substituted benzenediazonium salts the yields were 62-75%, but very small yields were obtained with the 2,4,6-trimethyl and the 2- and 4-nitro derivatives (Kikukawa et al., 1979). The two nitrodiazonium salts are good substrates in the Meerwein reaction... 

A solution of 25.8 g. (0.20 mole) of 4-amino-2,2,4-trimethyl-pentane (ierf-octylamine) (Note 1) in 500 ml. of C.P. acetone is placed in a 1-1. three-necked flask equipped with a Tru-Bore stirrer and a thermometer and is diluted with a solution of 30 g. of magnesium sulfate (Note 2) in 125 ml. of water. Potassium permanganate (190 g., 1.20 moles) is added to the well-stirred reaction mixture in small portions over a period of about 30 minutes (Note 3). During the addition the temperature of the mixture is maintained at 25-30° (Note 4), and the mixture is stirred for an additional 48 hours at this same temperature (Note 5). The reaction mixture is stirred under water-aspirator vacuum at an internal temperature of about 30° until most of the acetone is removed (Note 6). The resulting viscous mixture is steam-distilled approximately 500 ml. of water and a pale-blue organic layer are collected. The distillate is extracted with pentane, the extract is dried over anhydrous sodium sulfate, and the pentane is removed by distillation at atmospheric pressure. The residue is distilled through a column (Note 7) at reduced pressure to give 22-26 g. (69-82%) of colorless 4-nitro-2,2,4-trimethylpentane, b.p. 53-5473 mm., < 1.4314, m.p. 23.5-23.7°. 

Nitro-2-methyl- 439 5-Nitro-4-nitrato-2-methyl- 439 5-Nitro-2-nitrato-2,4,4-trimethyl- 439 5-Nitro-2-oxo- 310... 

Dimethyl-benzyl- 648, 678 Dimethyl-tert.-butyl- 649, 661 Dimethyl-cyanmethyl- 648, 678 Dimethyl-(4-nitro-benzyl)- 678 Trimethyl- 648... 

Dimethyl-6-methylamino-5-quinoxalinamine (175) (prepared freshly as an ethanolic solution by catalytic hydrogenation of the corresponding nitro compound) and cyanogen bromide gave 3,4,8-trimethyl-3//-imidazo-[4,5-/]quinoxalin-2-amine (176) (20°C, 3.5 h 75%) the analogous... 

Dimethoxy-6-methyl-7-nitro-5-quinoxalinecarbonyl chloride (88, R = Cl) gave 2,3-dimethoxy-6A(A(-trimethyl-7-nitro-5-quinoxalinecarboxamide (88, R= NMe2) (MejNH, THE, 20°C, 19 h >95%), V-(tert-butoxycarbonyl-methyl)-2,3-dimethoxy-6-methyl-7-nitro-5-quinoxalinecarboxamide (88, R = NHCHj CO2BU ) (Bu 02CCH2NH2-HC1, EtaN, THE substrate/THEj drop-wise, N2, 5 min then 20°C, 24 h 77%), and a variety of analogs similarly. ... 

One-pot tandem sequences involving 1,4-addition and ISOC as the key steps have been developed for the construction of N and 0 heterocycles as well as of carbocycles [44]. In this sequence, the nitronate arising from 1,4-addition to an a, -unsaturated nitro alkene is trapped kinetically using trimethyl silyl chloride (TMSCl). The resulting silyl nitronate underwent a facile intramolecular 1,3-dipolar cycloaddition with the unsaturated tether (e.g.. Schemes 20-22). 

Unlike such unstable intermediates, the first, rare example of reversible dissociation of a carbon-carbon a bond into a stable carbocation and carbanion was reported for a nitro-dicyano compound (20) prepared from trimethyl- and triphenyl-cyclopropenylium tetrafluoroborate ([4" ]BF4 and [5 JBFJ) with the potassium salt of p-substituted-phenylmalononitrile anions (Arnett et al., 1983 Troughton et al., 1984 Arnett and Molter, 1985). Other ionically dissociative malononitrile derivatives have been prepared from such carbocations as the tropylium [S ] (Arnett and Troughton, 1983) and the tris(p-methoxyphenyl)methylium [93 j (Arnett and Troughton, 1983) ions. 

For species 11 we will use the intrinsic barrier for hydroxide addition to trimethyl phosphate, G = 19 (calculated using rate and equilibrium data from reference 100) and assume the same value for the attack of hydroxide at sulfur on dimethyl sulfate. This (nonobservable) rate will be estimated using a Brpnsted type plot from the rate constants for diaryl sulfates (diphenyl sulfate,and bis p-nitrophenyl sulfate), estimated from the rate for phenyl dinitrophenyl sulfate,assuming equal contributions for the two nitro groups. This gives ftg = 0.95, and thus for dimethyl sulfate log k = 11.3... 

Experimental Preparation of 6-nitrospiropyran 2 (R = Bu). Triethyl-amine (2.65 g, 26 mmol) was added to a suspension of 2,3,3-trimethyl-7V-butylindolinium iodide (9.0 g, 26 mmol) and 5-nitro-salicylaldehyde (4.38 g, 26 mmol) in EtOH (100 ml) under stirring. The mixture was refluxed for 2 h, and filtered off. Recrystallization from hexane gave 6-nitrospiropyran 2 (R = Bu). Also, spiropyran 2 was isolated from the filtrate, which was evaporated under reduced pressure and then was chromatographed on silica gel with dichloromethane-methanol (60 1 v/v). Total yield of 2 (8.3 g) is 88%. 

Experimental Preparation of 5, 6-dinitrospirobenzothiopyran 44b. A mixture of 5-nitro-l,3,3-trimethyl-2-methyleneindoline (0.38 g, 1.75 mmol) and 5-nitro-thiosalicylaldehyde (0.22 g, 1.2 mmol) in EtOH (50 ml) was refluxed for 2h, and then evaporated under reduced pressure. The residue was chromatographed on silica gel with benzene-acetone (15 1, v/v) and recrystallized from dichloromethane-hexane to give 44b (R1 = N02, R2 = 6-N02)(0.30 g, yield 65%). 

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