A New Tetratertiary Phosphine Ligand and Its Use in Pd-Catalyzed Allylic Substitution
Résumé
A new tetraphosphine, the cis-cis-cis-1,2,3,4-tetrakis(diphenylphosphinomethyl)cyclopentane (Tedicyp)
1 has been synthesized, characterized, and used in Pd-catalyzed allylic substitutions. The
Tedicyp was easily prepared in seven steps from the commercially available himic anhydride. The
structure of the complex Tedicyp-borane was determined by X-ray analysis. The tetraphosphine
in combination with [Pd(è3-C3H5)Cl]2 affords a very efficient catalyst for allylic substitution of several
allylic acetates. Under mild conditions, very high turnover numbers and turnover frequencies have
been obtained.