Final answer:
Hydroboration-oxidation and the acid-catalyzed addition of water are two distinct mechanisms that accomplish the same transformation of alkenes into alcohols. They both involve the addition of an -OH group to the alkene, and in each case, water acts as a nucleophile or takes part in proton transfer steps.
Step-by-step explanation:
Hydroboration-oxidation and the acid-catalyzed addition of water are both mechanisms by which alkenes can be converted to alcohols. In the hydroboration-oxidation reaction, borane (BH3) adds to the alkene, followed by oxidation with hydrogen peroxide to give the alcohol. On the other hand, in the acid-catalyzed hydration of alkenes, the presence of a strong acid like sulfuric acid catalyzes the addition of water across the double bond. This process involves the protonation of the alkene to form a carbocation, which is then attacked by a water molecule, followed by deprotonation to yield the alcohol. Despite differences in mechanisms, both reactions achieve the same outcome: the addition of an -OH (hydroxyl) group to the carbon of the alkene, effectively transforming it into an alcohol.
An important similarity between the two is the final product: despite different reagents and conditions, both reactions form alcohols from alkenes. In both mechanisms, H2O serves as a nucleophile that adds to the alkene. Furthermore, they both involve a three-step process: electrophilic addition, nucleophilic attack, and proton transfer to form the alcohol. In acid-catalyzed hydration, water acts both as a nucleophile (attacking the carbocation intermediate) and as a proton donor or proton acceptor, exemplifying its amphiprotic nature as described in Brønsted-Lowry acid-base theory.