Practical Synthesis of 2,3,4,5‐Tetramethoxytoluene

Uncommon Regioselectivity in Thiacalix[4]arene Formylation

“…Vilsmeer−Haack reaction of compound 2 (Scheme ) was carried out under several reaction conditions. After the formation of active formylation agent (DMF + POCl 3 ), the reaction was carried out either at ambient (20 °C) or at elevated (70 °C) temperatures.…”

Synthesis of Coenzyme Q10

“…[6] The free OH of 6 was protected by ethyl and isopropyl groups to produce 2b (87 %) and 2c (65 %), respectively (Scheme 2). [6] The free OH of 6 was protected by ethyl and isopropyl groups to produce 2b (87 %) and 2c (65 %), respectively (Scheme 2).…”

“…Data for 5c: 1 3,7,11,15,19,23,27,31,35,39-Decamethyl-1-(3-isopropoxy-2-methyl-4,5,6-trimethoxyphenyl)tetraconta-2,6,10,14,18,22,26,30,34 Coenzyme Q 10 (1) from 5cЈ: Following the same CAN oxidation procedure as was used starting from 5bЈ, the reaction of 5cЈ (0.18 g, 0.19 mmol), a solution of ammonium cerium(IV) nitrate (0.31 g, 0.57 mmol) in H 2 O (1 mL), and 64 % HNO 3 (0.02 mL, 0.38 mmol) in MeCN (3 mL) and THF (3 mL) at 0°C for 30 min produced 1 (0.13 g, 0.15 mmol, 79 %) as an orange solid after purification by SiO 2 column chromatography. The crude product was purified by SiO 2 column chromatography to give 4aЈ (2.51 g, 6 The mixture was heated at 40°C for 8 h, then allowed to cool to room temperature, diluted with CH 2 Cl 2 , washed with 10 % NH 4 Cl, dried with anhydrous Na 2 SO 4 , filtered, and concentrated under reduced pressure.…”

A Green and Efficient Synthesis of 1-Chloromethyl -2,3,4,5-Tetramethoxy-6-Methylbenzene

“…31.4-33.9 °C (lit. 14 2-Bromo-3,4,5-trimethoxytoluene (3): A stirred mixture of 2 (18.2 g, 0.1 mol) and NaBr (11 g, 0.11 mol) in acetic acid (100 mL) was treated dropwise with 30% H 2 O 2 (50 mL, 0.45 mol) for 2 h at 40 °C. Water (150 mL) and petroleum ether (100 mL) were then added, and stirring was continued for 5 min.…”

“…However, none of them is attractive enough for the large-scale synthesis of 4 due to the drawbacks such as the use of some expensive, toxic mat erials(MeI,Me 2 SO 4 ,CuI,CuCN), and complicated multistep procedures. [9][10][11][12][13][14][15] Therefore, a convenient and practical method for the synthesis of 4 is still in demand. We have developed a simple and efficient route for the synthesis of 2,3,4,5tetramethoxytoluene 4.…”