The low dielectric constant and high self-dissociation constant of water in a temperature range between 150 and 250 °C make it a very appealing solvent for synthesis. Surprisingly, while organic chemistry in water at low temperature or around its critical point has been investigated in detail, very little seems to be known about the behaviour of organic molecules under hydrothermal conditions. The present work thus aims at shading some light on this field. As a start, we decided to investigate the reactions in which alcohols can undergo in water in the above-mentioned temperature range. Knowing that very strong salt effects on organic reactions have already been observed in super critical water, the impact of salt on the outcome of our tests was also investigated in detail.