In order to resolve tetrahedron-type chiral clusters, three chiral clusters
containing a functionally substituted cyclopentadienyl ligand were prepare
d, and the reactions of functional substituents were investigated. The este
r group was hard to hydrolyze while hydrazide can easily condense with the
ketonic carbonyl on the cyclopenta- dienyl ring to form a cluster hydrazone
. Two optically active auxiliaries have been attached to the chiral framewo
rk; however, the diastereoisomers cannot be separated by silica gel chromat
ography. Their presence was established by C-13 NMR spectra.