Preparation and application background and overview of 4,4′-dinitro-2,2′-bipyridyl-N,N-dioxide
4,4′-dinitro-2,2′-bipyridyl-N,N-dioxide is an important organic intermediate, such as it can be used to prepare 4,4′-dibromo-2, 2′-bipyridyl, 4,4′-dibromo-2,2′-bipyridyl is an important intermediate in the synthesis of 2,2′-bipyridyl compounds and is widely used in the research of fuel-sensitized solar cells.
Preparation and application of 4,4′-dinitro-2,2′-bipyridyl-N,N-dioxide
4,4′-dinitro-2,2′-bipyridyl-N,N-dioxide is prepared as follows:
1) Add 50ml water to 100ml four-necked flask 11 triglyceride carbonate, then add 7.5g (48mmol) 2,2′-bipyridine, add 1.6g (0.0048mmol) sodium tungstate and 2.2g (0.0048mmol) ) trioctyl methyl ammonium hydrogen sulfate, raise the temperature to 60°C, slowly add 18.75ml (182.4mmol) 30% hydrogen peroxide dropwise, react for 5 hours, monitor by HPLC without raw materials, filter, wash three times with water, and dry to obtain 2,2′- Bipyridyl nitrogen oxide 7.2g, yield 80%, purity 99.4% (HPLC). 1H-NMR of 2,2′-bipyridyl nitrogen oxide (DMSO-d6): 8.31-8.33 (d, J=6.3Hz, 2H) 7.39-7.62 (m, 6H).
2) Add 35ml (657mmol) concentrated sulfuric acid and 40ml 30% fuming sulfuric acid into a 250ml four-necked flask, add 25g (133mmol) 2,2′-bipyridyl nitrogen oxide in batches, raise the temperature to 110°C, and add 80ml dropwise (1942mmol) fuming nitric acid, react for 5 hours after the dropwise addition, and monitor by HPLC. Pour the reaction solution into ice water, filter, recrystallize and dry to obtain 18.5g of yellow solid, with a yield of 50.2% and a purity of 99.2%. 1H‑NMR of 4,4′-dinitro-2,2′-bipyridyl-N,N-dioxide (DMSO‑d6): 8.69 (d, 2H, J= 3.3Hz) 8.60 (d, 2H, J=7.2Hz) 8.36 (dd, 2H, J=7.2Hz, J=3.3Hz).
Preparation and application of 4,4′-dinitro-2,2′-bipyridyl-N,N-dioxide
4,4′-dinitro-2,2′-bipyridine-N,N-dioxide can be used to prepare 4,4′-dibromo-2,2′-bipyridine: 50ml four-necked flask , add 80ml acetic acid, then add 10g (35.9mmol) 4,4′-dinitro-2,2′-bipyridyl nitrogen oxide, heat to reflux, add dropwise 19.89g (107.7mmol)/60ml acetyl bromide acetic acid Solution, HPLC monitors that there is no raw material, add 17g (89.8mmol) tin chloride to it, after all reduction, pour the reaction solution into ice water, adjust the pH to 10, filter, extract the mother liquor with ethyl acetate, spin dry, and recrystallize , dried to obtain 6.7g of 4,4′-dibromo-2,2′-bipyridine, with a yield of 59.4% and a purity of 99.2%. 1H-NMR of 4,4′-dichlorophenylboronic acid bromide-2,2′-bipyridyl (DMSO-d6): 8.59 (d, 2H, J=1.8Hz) 8.50 (d, 2H, J=5.1Hz) 7.79 (dd, 2H, J=5.1Hz, J=1.8Hz).
