Cleavage of the Zero Bridge in Bicycles by Fragmentation Reactions

Cleavage of the Zero Bridge in Bicycles by Fragmentation Reactions 

The transformation of VIII/3 to VIII/4 is called a fragmentation1 [3] [4]. As in the aldol reaction the reverse version of the fragmentation also is known (VIII/4 — VIII/3). An example of this reaction type is the so-called Prins reaction the acid catalyzed (base catalysis is also possible) addition of an olefin to formaldehyde in order to get a 1,3-diol. Further examples are known in the field of transannular reactions in medium-sized rings [5], 

1) This reaction type is called a Grob as well as a Wharton fragmentation [1] [2]. 

---

VIII. 1. Cleavage of the Zero Bridge in Bicycles by Fragmentation Reactions... 

---