Osmium tetroxide can similarly be used to oxidize alkenes to vicinal diols. Dihydroxylation of alkene produces diol, and dihydroxylation of alkyne produces vicinal dicarbonyl. Most notably periodic acid will cleave vicinal diols into two aldehyde or ketone fragments. It is a diol that has hydroxyl groups (-OH) on vicinal carbon atoms. The Sharpless oxyamination converts an alkene to a vicinal amino alcohol. The Upjohn protocol yields high conversions to the vicinal diol and tolerates many substrates. The reaction product is a vicinal diol. On commercial scales, the main route to vicinal diols is the hydrolysis of epoxides. Dihydroxylation is the process by which an alkene is converted into a vicinal diol. The reaction is related to the Sharpless dihydroxylation, which converts alkenes to vicinal diols. In vicinal dihalides, it forms alkenes, whereas in geminal dihalides, it forms alkynes. Enolates can also be used as nucleophiles for vicinal difunctionalization reactions. In vicinal difunctionalization the proton is replaced by another electrophile. Further, it is the vicinal hyperconjugative effects that keep the molecule in the staggered conformation. TEC operates the Charleroi Pre-metro, which includes sections of Vicinal track.