Basic Transformations of the Vinyl Side Chain

Conversion of the natural product quinine into its alkyne analogue 26 was reported at the beginning of the twentieth century [16], but to our surprise, no further work on this potentially interesting and useful class of compounds had come forward since then. Similarly, transformations such as oxidative cleavage or degradation to the ketone functionality at carbon C3 had remained unexplored until the 1990s. 

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