Titanocene pentaselenide

The reaction of selenadiazole 121a with titanocene pentaselenide in xylene at 140 °C (15 min) affords titanocene complex 194 in 34% yield (Scheme 22) <1999SM1703>. The titanocene complex 194 was treated with CSC12 to afford the l,3-diselenole-2-thione 195. 

An interesting new entry into metallocene-containing dithiolato and diselenolato complexes (see also Section 16.5.2.4.3) are the reactions of titanocene pentasulfide (57) or pentaselenide (58) with activated alkynes.83 Titanocene dithiolates (59) and diselenolates (60) with X = CF3 and C02Me were obtained. The authors also performed a number of exchange reactions with the Se compound (60 X = CQ2Me). 

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