The three regioisomers of beta-cyclodextrin 6-difunctionalized with NH(2) groups (6(A),6(X)-diamino-6(A),6(X)-dideoxy-beta-cyclodextrin, A,X-CDNH(2), X = B, C, or D) were synthesized. Their binary and ternary copper(II) complexes with amino acids were characterized by ESR and electronic spectroscopy. Furthermore, the binary copper(II) complexes were used as eluent in ligand exchange chromatography (LEC), to resolve racemates of unmodified amino acids. HPLC separation of enantiomers of aromatic amino acids was obtained only when the complex [Cu(A,B-CDNH(2))](2+) was used as eluent. The two complexes with the other two regioisomers did not show chiral recognition ability. Circular dichroism (c.d.) spectroscopy studies of the ternary complexes with D- and L-amino acids carried out in the presence and in the absence of 1-adamantanol, suggested a recognition mechanism that involves the cyclodextrin cavity, only in the case of ternary A,B-CDNH(2) complexes.

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Ferrocenes bearing chiral pendants are investigated through VCD and ECD. The VCD spectra are best interpreted by GVPT2-anharmonic DFT calculations. Diagnostic bands related to the absolute configuration of the title compounds are found in both kinds of spectra.

The direct HPLC enantiomeric separation of several ferrocenylalcohols on the commercially available Chiralcel OD and Chiralcel OJ columns has been evaluated in normal-phase mode. Almost all the compounds were resolved on one or both chiral stationary phases (CSPs) with separation factor (alpha) ranging from 1.06 to 2.88 while the resolution (R(s)) varied from 0.63 to 12.70 In the separation of the alpha-ferrocenylalcohols 1a-e and the phenyl analogues 2a-e, which were all resolved except 1c, a similar trend in the retention behavior for the two series of alcohols was evidenced and the selectivity was roughly complementary on the two investigated CSP. For three ferrocenylacohols, chosen as model compounds, the influence of the mobile phase composition and temperature on the enantioseparation were investigated and additional information on the chiral recognition mechanism were deduced from the chromatographic behavior of their acetylderivatives.

The C2-symmetrical “salen” ligand (+)-9 bearing two [5]ferrocenophane substituents has been prepared in five steps starting from readily available diacetylferrocene, p-hydroxybenzaldehyde and (R,R)-N,N’-diphenylethylenediamine. Reaction of (+)-9 with Mn(OAc)3, Co(OAc)2 ZnEt2 or UO2(OAc)2 gave the corresponding metal-complexes which were characterised by spectroscopic methods.