ChemicalBook CAS DataBase List 4-Dibenzothiopheneboronic acid

4-Dibenzothiopheneboronic acid synthesis

12synthesis methods

Product Name:4-Dibenzothiopheneboronic acid
CAS Number:108847-20-7
Molecular formula:C12H9BO2S
Molecular Weight:228.07

132-65-0 Synthesis

132-65-0
377 suppliers
$6.00/5g

6990-27-8 Synthesis

6990-27-8
8 suppliers
$281.00/10ml

7732-18-5
470 suppliers
$13.50/100ML

108847-20-7
343 suppliers
$11.19/1G

Yield:108847-20-7 91%

Reaction Conditions:

Stage #1: dibenzothiophenewith N,N,N,N,-tetramethylethylenediamine;n-hexyllithium in hexane; for 2 h;Inert atmosphere;Reflux;
Stage #2: bromobis(dimethylamino)borane in hexane at 0;Inert atmosphere;
Stage #3: waterwith hydrogenchloride at 0 - 10; pH=2 - 3;

Steps:

5 Example 5

Under nitrogen protection, Dibenzothiophene (18.4 g, 0.1 mol) and n-hexane 85 mL were added to the reaction flask. Then TMEDA (12.8g, 0.11mol) was added, Become a clear solution with stirring, Then 2.3 M n-HexylLi hexane solution (48 mL, 0.11 mol) was added dropwise. Then the temperature was raised to reflux for 2 hours. Then cool down to 0 °C, Start adding BrB(NMe2)2 (18.7g, 99% purity, 0.105mol), After the addition is completed, Stirring reaction, TLC detection of raw materials disappeared, Filter out the solids produced, Cool down to 0 °C again, Quenched by adding 10% aqueous hydrochloric acid dropwise. Adjust pH=2-3, control temperature does not exceed 10 °C during quenching, Extracted with 180 mL of ethyl acetate twice. After the organic layer was evaporated to dryness, methanol (25 mL) was added and stirred until the crude product was completely dissolved. Then, about 4 times of methanol water (105 mL) was slowly added dropwise until all the solids were precipitated. After filtration and drying, 20.7 g of a white solid dibenzothiophene-4-boronic acid was obtained in a yield of 91%. HPLC: 99.1%, 1H NMR structure consistent, consistent with the literature.

References:

CN109456350,2019,A Location in patent:Paragraph 0019

97511-05-2 Synthesis