Enolizable Alkylidene Heterocyclic and Carbocyclic Carbonyl Systems­: Valuable Vinylogous Donor Substrates in Synthesis

To the memory of Prof. Giovanni Casiraghi, our mentor, with deep gratitude (1939–2016)

Abstract

Controlled vinylogous carbon–carbon bond-forming reactions are useful options for providing the selective remote functionalization of conjugated carbonyl substrates. Remotely enolizable alkylidene heterocyclic and carbocyclic carbonyl compounds are pro-nucleophilic substrates that may be engaged in highly valuable chemical transformations. This review emphasizes the merits of these recently discovered vinylogous donors in the chemo-, regio- and stereoselective synthesis of many functionality-rich products.

1 Introduction

2 Alkylidene Oxindoles

3 Alkylidene Pyrazolinones

4 Alkylidene Furanones

5 Alkylidene Azlactones

6 Cycloalkylidene Carbonyl Compounds

7 Alkylidene Indenones

8 Cycloalkylidene Malononitriles

9 Conclusion

Key words

alkylidene carbocycles - alkylidene heterocycles - remote functionalization - vinylogous donors - vinylogy

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