Syntheses and characterization of Cp 2Ce[η 3-N(QPPh 2) 2] (Q = S, Se) and Cp 2Ce[η 3-N(SP iPr 2)(SePPh 2)

Abstract

The compounds Cp 2Ce[η 3-N(QPPh 2) 2] (Q = S ( 1), Se ( 2)) and Cp 2Ce[η 3-N(SP i Pr 2)(SePPh 2)] ( 3) have been synthesized from the protonolysis reactions between Cp 3Ce and HN(QPPh 2) 2 or HN(SP i Pr 2)(SePPh 2) in THF. The structures of these compounds have been determined by X-ray crystallographic methods. The three compounds have similar structures in which the ligands are coordinated to Cp 2Ce moiety in an η 3 fashion through the two chalcogen atoms and an N atom. Whereas the 77Se NMR resonances are normal the 31P NMR resonances are shifted to much lower frequencies than in similar rare-earth compounds.