Hydroxyl reaction +EtOH

Oxidation of the hydroxyl group in 186 with pyridinium chlorochromate (PCC) in CH2CI2 affords the aldehyde 197. The reduction of 197 back to 186 is possible in EtOH in the presence of TiCl4, whereas upon treatment of 197 with diisobutyl-aluminium hydride a competitive reaction with the fullerene core was observed. 

Protection of the same hydroxyl with a photolabile group as in 329 (Scheme 4.98) ensured its removal upon irradiation under neutral conditions. In this experiment the formation of the phenolic derivative 331 was ascertained by NMR data. Epoxide ring opening in the latter followed by the usual set of reactions proceeded readily upon exposure of 331 in THE solution to nucleophiles like EtOH, EtSH, or n-PrNH2 and yielded the respective final adducts 332a-c. ... 

Even with methanol, some syn addition occurs when the reaction is carried out in dioxane ". Thus anti addition appears to be favoured in strongly protic solvents (MeOH, EtOH), but syn addition becomes significant as the solvent becomes less hydroxylic (higher alcohols), or aprotic (dioxane). We shall see this same trend appear when the addition of thiols is considered. 

Polyurethane (PU) PV membranes were reported by Schauer et al. (1999). PU membranes were prepared by the reaction of toluene-2,4-diisocyanate with hydroxyl-terminated oligomers. Oligomers were either liquid polybutadiene (PB) (MW 3000) or propylene oxide-based PEs (MW 420 and 4800). The prepared membranes were used in PV of binary mixtures of water-EtOH, water-dioxane, and EtOH-toluene, respectively. Membranes obtained from the polymer quatemized poly[3-(N, N -dimethyl)aminopropylamide-co-acrylonitriles] showed selective separation of water from aqueous EtOH solution by PV (Yoshikawa et al. 1991). The separation factor toward water reached over 15,000. Membrane performance showed a good correlation to membrane polarity. DSC melting endotherms of the water-swoUen membranes were studied to clarify the state of water in the membrane. The resnlts suggested that there were two states of water in the membrane bound and free. The higher the fraction of bound water in the membrane, clearly, the more preferentially was water permeated. 

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