[nancy960]

My main reactant is dibromofluorenone and I used bis(pinacolato)diboron, Pd(dppf)2Cl2, potassium acetate and dioxane as my solvent.
But even I've tried a few conditions, the conversion was remain very low.
Should I add base in aqueous solution or just in solid?
The solution after reaction shows up dark brown and muddy, the TLC test shows there is still reactant remain.

Thanks for your *delete me*

[phth]

If reactants remain then the conditions are not conducive to product, or the catalyst [Pd(0)] is being quenched by oxygen, for example.

[nancy960]

I tried to react under Argon atmosphere but the yield was really low.From the NMR spectrum it seem to be failed and not work.

[kriggy]

What about trying lithium-halogen exchange and then quech with the bpin?

[phth]

I tried to react under Argon atmosphere but the yield was really low.From the NMR spectrum it seem to be failed and not work.

how did you preclude oxygen and water?
https://www.chemistryviews.org/details/education/4308331/Tips_and_Tricks_for_the_Lab_Air-Sensitive_Techniques_2.html
https://www.chemistryviews.org/details/education/4360441/Tips_and_Tricks_for_the_Lab_Air-Sensitive_Techniques_3.html

It should work unless 1) reagents bad 2) experimental error

[blackcat]

What about trying lithium-halogen exchange and then quech with the bpin?

There is carbonyl group in the reactant

[blackcat]

I tried to react under Argon atmosphere but the yield was really low.From the NMR spectrum it seem to be failed and not work.

It is not only about the atmosphere in which the reaction was conducted is important. You need to degas your solvent before the reaction. This can be by sparging or freeze-pump-thaw. The former works better for large volume, the latter for smaller volume.