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Trimethyloxonium tetrafluoroborate can be used as a methylating agent for the methylation of hydroxyl/carboxyl functional groups. It is capable of methylating polyfunctional carboxylic acids. It is also used as a catalyst for the polymerization of cyclic sulfides and ethers.
T 1628 (OTTO) Trimethyloxonium tetrafluoroborate, 95% Cas 420-37-1 - used in a complex, multistep synthesis directed towards spirastrellolide, a marine natural product.