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ChemicalBook CAS DataBase List Di-tert-butyl dicarbonate
24424-99-5

Di-tert-butyl dicarbonate synthesis

10synthesis methods
The preparation of Di-tert-butyl dicarbonate is as follows:To a monoester sodium salt solution were added 2g of N, N-dimethylformamide, 1g of pyridine, 1g of triethylamine,Cooling to -5~0°C, 60g diphosgene was slowly added dropwise within 1.5h dropwise addition was complete, warmed to room temperature (25°C), incubated for 2h, the reaction was allowed to stand after filtration, washing organic solution. Dried with anhydrous magnesium sulfate, the solvent was distilled off at atmospheric pressure to give crude product 65~70g. After cooling and crystallization, 57-60g of di-tert-butyl dicarbonate were obtained in a yield of 60-63%.
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Yield:24424-99-5 91 %

Reaction Conditions:

with triethylamine in tetrachloromethane at 25;

Steps:

S3

S51: in the beaker with electromagnetic stirring bar, add 20.0 grams (0.076 moles) of di-tert-butyl tricarbonate dissolved in carbon tetrachloride solution and triethylamine as catalyst, release carbon dioxide immediately and rapidly;S52: stirring at 25° C. for 45 minutes to release carbon dioxide completely, and then adding 35 ml of aqueous solution containing an appropriate amount of citric acid enough to make the water layer weakly acidic;S53: The organic layer was separated, dried with anhydrous magnesium sulfate, concentrated with a rotary evaporator at 25° C., and the residue was distilled under reduced pressure to obtain a colorless liquid of di-tert-butylphenol dicarbonate.

References:

CN115322096,2022,A Location in patent:Paragraph 0063-0067

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