Preparation of rylene-5-boronic acid_industrial additives

Preparation background and overview of rylene-5-boronic acid

Nalylene-5-boronic acid can be used as a pharmaceutical synthesis intermediate and can be used in laboratory organic synthesis processes and chemical and pharmaceutical synthesis processes.

Preparation of rylene-5-boronic acid

The preparation of rylene-5-boronic acid is as follows: Dissolve 11.7g of commercial 5-bromoacenaphthene in a mixed solvent of 50ml anhydrous toluene and 50ml anhydrous ether, and cool the resulting solution to -40°C. To the resulting solution, 35 ml of a 1.6 M hexane solution of n-butyllithium was added dropwise, and the temperature was subsequently raised to -10°C. After 2 hours, the resulting solution was cooled to -70°C, and then another solution prepared by dissolving 35 ml of triisopropoxyborane in 50 ml of diethyl ether was added dropwise to the solution. The resulting solution was stirred at -70°C for 3 hours and then left to stand overnight. After one night, the resulting solution was acidified with 10% by weight of dilute hydrochloric acid, and the organic layer was extracted with toluene. The organic layer was washed with dilute hydrochloric acid and saturated sodium chloride solution, dried over anhydrous sodium sulfate, and the organic solvent was distilled with an evaporator. The residue was crystallized using toluene/hexane to obtain 4.5 g (yield 45%) of rylene-5-boronic acid.

Preparation and application of rylene-5-boronic acid

The application of rylene-5-boronic acid is as follows: under argon protection, 0.83g (4mmol) 2-bromoquinoline, 0.95g (4.8mmol) rylene-5-boronic acid and 0.28g (0.24mmol) ) Tetrakis triphenylphosphine palladium was dissolved in 25 mL of THF, then polycarbonate was dropped into the reaction system and 10 mL of an aqueous solution containing 1.10 g (8 mmol) potassium carbonate was added, heated, and the reaction was stirred for 10 hours under reflux. After the reaction is complete, cool to room temperature naturally, and extract three times with 15 mL of water and 15 mL of ethyl acetate. The organic phase was dried over anhydrous magnesium sulfate, filtered, and the solvent in the filtrate was rotary evaporated to obtain an oily crude product. The oily crude product was subjected to silica gel column chromatography using a mixture of methylene chloride and petroleum ether with a volume ratio of 1:3 as the eluent. Separate and purify, evaporate the solvent, and dry to obtain 0.67g of pure solid material 2-(acenaphthylene-5-yl)quinoline, with a yield of 59.5% sodium pyrithione.