Hydrocarbons terpenoic

Figure 12. Structures of terpenoic hydrocarbons a-pinene, /3-pinene, cis-pinane, trans-pinane and 2 carene resolved on a-cyclodextrin hydrate (Koscielski et al., 1986).

The ability of a- and 3-CD complexation to modify the gas-partition chromatography system for separation of terpenoic hydrocarbons is exemplified in Fig. 1 for a-pinene. 

As suggested by the chromatograms in Fig. 1, both a- and 3-CD form inclusion complexes with a pinene. Approximative estimation of the stability of CD complexes indicates that 3-CD complex is much more stable than that of a-CD (the stability constant of the former complex is by one order greater than that of the latter). However, only a-CD complexation permits substantial chiral recognition of terpenoic hydrocarbons. This stereoselectivity originating from specific interactions between a-CD and guest molecules in inclusion complexes is markedly influenced by temperature and nature of the matrix medium. 

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