Clostridium acetobutylicum, ATCC 824, is a commercially valuable bacterium sometimes called the "Weizmann Organism", after Jewish-Russian-born Chaim Weizmann, then senior lecturer at the University of Manchester, England, used them in 1916 as a bio-chemical tool to produce at the same time, jointly, acetone, ethanol, and butanol from starch.
For pyrylium salts with alkyl substituents such as 2,4,6-trimethylpyrylium salts, the best method uses the Balaban-Nenitzescu-Praill synthesis from tertiary butanol and acetic anhydride in the presence of tetrafluoroboric, perchloric, or trifluoromethanesulfonic acids.