Bromine → 2,7-Bis-(but-2-enoyl)-thioxanthen-9-one

Beteiligte Stoffe

Reaktionsschritte

To 1-[7-(but-2-enoyl)-9H-thioxanthen-2-yl]-but-2-en-1-one, which is synthesized by thioxanthene and crotonoyl chloride in the presence of aluminium chloride as described in WO2005-080337A1, dissolved in dichloromethane are added bromine (2.0 equiv.) and aqueous tetra-n-butylammonium bromide (0.5 equiv.). Stirring the reaction mixture at room temperature and succeeding extractive work-up and purification give 2,7-bis-(but-2-enoyl)-thioxanthen-9-one, which is transformed into the compound of example 9 as described in example 4.

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