Another Anomaly, Vilsmeier-Haack-Arnold Formylation of S-Selinene

Another Anomaly, Vilsmeier-Haack-Arnold Formylation of S-Selinene 

5-Selinene is another sesquiterpene found in woods. Its behaviour in the Vilsmeier-Haack-Arnold reaction is, like that of the acylation of cedrene using titanic chloride as a catalyst, another interesting and surprising piece of sesquiterpenoid carbocation chemistry. 

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