Modular synthesis of a new family of tripodal ligands, all-cis-1,2,3-tris(diphenylphosphinomethyl)cyclopropane and relatives

Bisbenzyl-protected all-cis-1,2,3-tris(hydroxymethyl)cyclopropane has been obtained in three steps from commercially available cis-2-butene-1,4-diol (75% overall yield) and used to prepare a number of all-cis-1,2,3-trisubstituted cyclopropane derivatives. Among them, the new tripodal ligand all-cis-tris(diphenylphosphinomethyl)cyclopropane (TriCyp-PPP) has been demonstrated to furnish-with pi-allylpalladium chloride dimer-a highly active catalyst for the allylation of diethyl methylmalonate enolate with allyl acetate.