Thermolysis and [3+2]‐Cycloaddition Reactions of 2,3‐Diferrocenyl‐ and 2,3,‐Diruthenocenylcyclopropenones

Abstract

2,3‐Diferrocenyl‐ and 2,3‐diruthenocenylcyclopropenone undergo thermolysis at ∼180°C with opening of the small ring via ketenocarbenes. Intramolecular transformation of the latter occurs with elimination of CO to yield dimetallocenylacetylenes. Alternatively, they enter into 1,3‐dipolar cycloaddition reactions with C≡C or C˭C multiple bonds to give cyclopentadienone or cyclopentenone derivatives, respectively.

Keywords:

• [3+2]‐cycloaddition
• diferrocenylcyclopropenone
• diruthenocenylcyclopropenone
• ring opening
• thermolysis
• X‐ray structural analysis

Acknowledgments

This work was supported by the DGAPA–UNAM (Mexico, grant IN 207102‐3). Thanks are due to M. L. Velasco, J. Perez, H. Rios, E. R. Patiño and R. I. Del Villar Morales for their technical assistance.