Cyclic alkynes from ring-closure reactions

1 Cyclic Alkynes from Ring-Closure Reactions 

As this chapter is concerned with the properties of the carbon-carbon triple bond, we will mainly discuss ring-closure reactions which make use of the special reactivity of acetylenic systems — either at the sp-hybridized carbon atoms or at the propargylic centers. It is obvious, however, that virtually all ring-closure reactions can be employed to close a ring with a triple bond. Earlier reviews have dealt with these possibilities in quite some detail [1-3]. 

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