2-bromo-spiro[fluorene-7,9'-benzofluorene] synthesis

Yield:1099593-10-8 78%

Reaction Conditions:

Stage #1: 1-(2-bromophenyl)naphthalenewith n-butyllithium in tetrahydrofuran at -78; for 1 h;
Stage #2: 2-bromofluoren-9-one in tetrahydrofuran at 18 - 28; for 12 h;
Stage #3: with hydrogenchloride;acetic acid at 120; for 5 h;

Steps:

2

The experimental device was sufficiently dried. In a 2L three-necked flask, 31.1 g (110 mmol) of 1- (2-bromobenzene) naphthalene was added. 600 ml of dried tetrahydrofuran was added. After dissolution, the temperature was lowered to -78 ° C, and 48 ml of 2.5 M (120 mmol, 1.2eq.) Of n-BuLi. After the dropwise addition was completed, the mixture was stirred at this temperature for 1 hour, and 25.9 g (100 mmol, 1.0 eq.) Of 2-bromofluorenone was added dropwise at the same temperature. After the dropwise addition was completed, the mixture was stirred at room temperature for 12 hours.After the reaction is over, add 4M hydrochloric acid solution,Extract with dichloromethane, wash the organic phase with saturated brine until neutral, dry, spin off the solvent, fully dry, and then feed into a 2L dry three-necked flask. Add 600ml acetic acid and 150ml HCl, warm to 120 ° C, and reflux for 5 hours. To end the reaction. After cooling to room temperature, 500 ml of water was added to precipitate a solid, which was washed 4 times with water, dried, dried, and recrystallized from toluene and ethanol to obtain 34.7 g of intermediate (17) in a yield of 78%.

References:

CN106893581,2019,B Location in patent:Paragraph 0136; 0139; 0140; 0141; 0142