Influence of bromide ions on the synthesis of anomeric thiocyanates

The synthesis of anomeric thiocyanates with the α- and β-configuration is described. Reactions performed under standard conditions afforded the 1,2-trans derivatives as the main products, whereas in the presence of the quaternary ammonium salts, the 1,2-cis-thiocyanates were formed preferentially. The strong influence of the bromide ions on the distribution of the products is discussed.