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PIERRE MENASSA and CAMILLE SANDORN. Can. J. Chem. 63, 3367 (1985).The interaction of the inverted micelles of AOT (sodium di(2-ethylhexyl)sulfosuccinate) with different alcohols due to hydrogen bonding has been studied by means of infrared spectroscopy. Spectra of solutions of the alcohols with increasing concentrations of AOT showed a decrease in the intensity of the free OH stretching band. At the same time a new OH band due to a H-bonded alcohol-inverted micelle complex appears and its intensity increases as the intensity of the free band decreases. Calculated values of the equilibrium constants for the formation of the complexes n-alcohol-AOT, showed a decrease in alcohol-AOT association with the increase of the length of the aliphatic chains in the n-alcohols. Surprisingly, cholesterol behaved like a short chain while other cyclic alcohols like long chain alcohols.PIERRE MENASSA et CAMILLE SANDORFY. Can. J. Chem. 63, 3367 (1985).L'interaction dans le tttrachlorure de carbone des micelles inverses du bis(Cthy1-2-hCxyl) sulfosuccinate de sodium (AOT) avec differents alcools a Ct C CtudiCe par spectroscopie infrarouge. L'Ctude spectroscopique de differentes solutions d'alcool et d'AOT montrent une diminution de I'intensitC de la bande OH libre alors que paralltllement I'intensitC d'une bande associCe alcool-AOT augmente. Les calculs des constantes d'association n-alcool-AOT indiquent une diminution du degre d'association avec la longueur de la chaine hydrocarbure. Le cholestCrol se comporte comme un alcool j. chaine courte tandis que d'autres alcools cycliques se comportent comme des alcools j. chaine longue.

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. 64, 633 (1986). A relation has been found between the anesthetic potency of n-alcohols (rz = 1,3,6,7,9, 11, 14, and 16) and their association constants with polar groups in inverted micelles. From this point of view, cholesterol and 7-dehydrocholesterol behave like short-chain n-alcohols while cholestanol behaves like a long-chain n-alcohol. PIERRE M~NASSA, T H~R~S E LUSSIER et CAMILLE SANDORFY. Can. J. Chem. 64, 633 (1986). On a pu dkmontrer qu'il existe une relation entre le pouvoir anesthksique des n-alcools et leur constante d'association avec des groupements polaires dans des micelles Inverses, qui a Ct C determinCe pour rz = 1 , 3, 6,7,9, 11, 14 et 16. De ce point de vue, le cholestCrol et le dehydro-7 cholestCrol se comportent comme des 11-alcools a chaine courte alors que le cholestanol s'apparente aux 11-alcools 2 chaine longue.Alcohols are known to have anesthetic potency (1). Pringle et al. (2) have shown that this potency increases with the length of the hydrocarbon chain in n-alcohols. There is, however, a "cutoff" at CI3. While the latter still possesses a weak anesthetic potency, C14 has no anesthetic potency at all (3).In an attempt to find a correlation between this behavior and the physico-chemical properties of alcohols, Wilson et al. (4) compared the hydrogen bond (H-bond) forming tendencies in the series of alcohols from C, to CI8 by infrared spectroscopic means. They found that in neutral solvents, the free/H-bonded ratio for self-association is independent of the chain length. The same applies to ester carbonylln-alcohol association. Subsequently, MCnassa and Sandorfy (5) undertook similar studies in a membrane mimetic environment. Their system consisted of sodium di(2-ethylhexyl) sulfosuccinate (AOT) with traces of water in carbon tetrachloride to which an alcohol was added. The detergent AOT containing traces of water forms inverted micelles in carbon tetrachloride (6). The infrared spectra were recorded on a Nicolet model 5DXB Fourier-transform ir spectrometer with a resolution of 2cm-I. The method for computing association constants hos been given previously (5, 7). The association constants of n-alcohols with AOT exhibit a pronounced dependence on chain length. The alcohol/AOT association constant decreases with increasing chain length as shown in Fig. 1. The spectra give evidence that association occurs between the alcohols and the SO3-group of AOT. The carbonyl bands were not observably affected with the dilute solutions that were used in those studies. However, with higher water content and alcohol concentrations, alcohol/carbonyl (AOT) association could also be detected.More importantly, the H-bond association constants stopped decreasing at C l o (5) and remained constant at about 5 L mol-l.Thus there appears to be a parallelism between the effect of the chain length on the H-bond equilibria of alcohols in these systems and their anesthetic potency. While AOT can only be a remote model for actual cell membranes, an analogy exists: the alcohol (anesthetic) must cross a hydropho...