4-Bromo-1,2-dimethoxy-benzene

To a stirred solution of 19.8 g of 2-(n)-propylthio-l,3-dimethoxybenzene in 200 mL CH,C12 there was added 15.4 g elemental bromine dissolved in 100 mL CH2C1,. The reaction was not exothermic, and it was allowed to stir for 1 h. The reaction mixture was washed with H,0 containing sodium hydrosulfite (which rendered it nearly colorless) and finally washed with saturated brine. The solvent was removed under vacuum leaving 3 3.5 g of apale yellow liquid. This was distilled at 112-120 °C at 0.3 mm/Hg to yield 4-bromo-2-(n)-propylthio-l,3-dimethoxy-benzene as a pale yellow oil. Anal. (CnH 5Br02S) C,H. 

It was demonstrated that a redox shuttle compound, 4-bromo-l,2-dimethoxy-benzene (0.1 M) dissolved in 1 M LiPF /PC + DMC, protected the overcharge at 0.02C rate in Li/LiCoO 2025 coin cells (25 mAh), as shown in Fig. 4.18. When the additive was absent, the cell voltage V continued to increase and the heat H measured by a C80 calorimeter was generated at about 4.6 V by electrolyte decomposition. On the other hand, when the additive was present, the cell voltage stopped at 4.3 V and the input energy W= 4.3 V x 0.15 mA = 0.65 mW was completely converted to the heat consumed by the redox shuttle reaction. 

The reaction of 1-alkoxynaphtalenes with copper (II) bromide in benzene produced a mixture of 4-bromo-1-alkoxynaphtalenes and 4,4 -dialkoxy-l,l -binaphtyls. For instance, the reaction of 1-methoxynaphtalene 4 with copper(II) bromide in refluxing benzene for 2 h. gave a mixture of 4-bromo-1-methoxy-naphtalene 5 (47 %) and 4,4 -dimethoxy-l,l -binaphtyl 6 (45 %). In contrast, in similar reaction using alumina-supported copper(II) bromide at 30°C, only dimerization occurred and no brominated compounds were obtained. 

Ethanone, 1- [3-(l,l-dimethylethyl)-4-methoxy-5-nitrophenyl Benzaldehyde, 2 (l,l-dimethylethyl)-4-methoxy-5-nitro Benzene, 1,4-BIS- (1, l-dimethylethyl)-2 methoxy-5-nitro Benzene, 1-(1, l-dimethylethyl)-2, 5-dimethoxy-4-nitro Benzene, 1-(1, l-dimethylethyl)-2-methoxy-4 methyl-5-nitro Benzaldehyde, 5- (1, l-dimethylethyl)-2-methyl-3-nitro Benzaldehyde, 2- (1, l-dimethylethyl)-4,5,6-trimethyl-3-nitro Benzene, 5-(l, l-dimethylethyl)-2-methoxy-l, 3-dinitro Benzene, 1-(1, l-dimethylethyl)-4-methoxy-2-methyl 3-5-dinitro Benzene, 2-bromo-5- (1, l-dimethylethyl)-4-methoxy-l,... 

Benzene, l-azido-3,3-dimethoxy-l-pro-penyl-[56900-67-5], 57, 84 Benzene, (l-azido-2-iodo-3,3-dimethoxy-propyl)- [56900-66-4], 57, 84 Benzene,bromo-, [108-86-1], 55,51 58, 135, 136, 138... 

The crude tertiary alcohol (5 g) was dissolved in 50 mL benzene and added to 107 g 90% sulfuric acid. The reaction mixture was stirred for 1 h at 0-2°C and then poured onto ice. After processing and evaporatively distilling at 150-155°C (0.15 mmHg), 1 g 2,5-dimethoxy-8-bromo-4a-methyl-10a-carbethoxy-l,2,3,4,4a,9,10,10a-octahydrophenanthrene was obtained. 

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