Can we use Boron tribromide dimethyl sulfide complex to demethylate the methoxy groups on ring A of colchicine?

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Rafik Karaman

Dear Abdullah,

Yes indeed. Please see attached file.

Rafik

Shiv Kumar Yadav

it will demethylate but selectivity is not clear

Abdullah Ghawanmeh

this is my request I need two demethylated groups of four.

this transformation is only possible with enzymatic hydrolysis

Paramasivam Parthiban

In fact, BBr3 is a good one for demethylation of OCH3. You an find a number of reports from the internet.

Actually it is not possible to get BBr3 from suppliers.

Yes, always it should with a solvent. But instead of BBr3 dms you can prefer BBr3 dcm. Dimethyl sulfate itself a very good methylating agent.