Synthesis of Alkenylcarbene Complexes


The starting complexes 1 and 2 are easily accesible in two (for X=O) or three (for X=NR) steps, respectively, from iron carbonyls and vinyl oxiranes or butendiols [2],[3]. The ferralactones [4] formed in the first step can be alkylated with Meerwein salts either directly or after aminolysis with primary amines to give the corresponding carbene complexes with X=O or X=NR.X-ray structure of 1:

(to see the X-ray structure you need MDL Chemscape Chime plug-in)

[2] W. Förtsch, F. Hampel and R. Schobert Chem. Ber.1994, 127, 711.
[3] W. Förtsch, F. Hampel and R. Schobert Chem. Ber.1997, 130, 163.
[4] [4a] R. Aumann J. Am. Chem. Soc. 1974, 96, 2631. - [4b] R. Aumann, H. Ring, C. Krüger and R. GoddardChem. Ber. 1979, 112, 3644. - [4c] R. F. Heck and C. R. Boss J. Am. Chem. Soc., 1964, 86, 2580. - [4d] S. T. Hodgson, D. M. Hollinshead and S. V. Ley J. C. S. Chem. Commun. 1984, 494. - [4e] S. V. Ley Phil. Trans. R. Soc. Lond. A 1988, 326, 633. - [4f] S. V. Ley, L. R. Cox and G. Meek Chem. Rev. 1996, 96, 423.