Synthesis of Dithiafulvene-Dendralene Oligomers by Cascade Reactions

Synthesis of Dithiafulvene-Dendralene Oligomers by Cascade Reactions 

The focus of this chapter has so far not been so much on synthesis, but one very nice cascade reaction to dendralenes incorporating DTF donor groups and dicyanomethylene acceptor groups deserves mention. While TCNE can undergo a thermal [2+2] cycloaddition with electron-rich alkynes followed by electrocyclic ring opening [21, 39], TTF can undergo a similar reaction with electron-poor alkynes [40]. These observations were employed to construct a 

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