| Popis: |
Two strained bridgehead cage alcohols with a very short intramolecular OH...π distance, tetracyclo[5.3.0.0. 2,5 .0. 4,8 dec-9-en-3-ol and its 3-methyl derivative, have been synthesized. The IR spectra have been studied and discussed in relation to the starting ketone tetracyclo[5.3.0. 2,5 .0.0. 4,8 ] dec-9-en- 3-one. Considerable attractive OH-proton...π-electron interaction on the one hand and repulsive steric and oxygen-lone-pair... π forces on the other hand lead to a position of the hydroxyl bond, practically parallel to the double bond. Non-bonding proton..proton interaction in the 3-methyl compound causes increased C-H stretching frequencies of the alkyl groups involved. The IR-data of the ketone confirms the presence of non-bonding π-orbital interaction and shows the C=O vibration is subject to Fermi resonance. |
