Related Experiment Video
Updated: Apr 24, 2026

Author Spotlight: Functionalizing Metal-Organic Frameworks: Advancements, Challenges, and the Power of Post-Synthetic Ligand Exchange
Published on: June 23, 2023
An update of the rules for pyranoside sulfonate displacement
Karl J Hale1, Leslie Hough, Soraya Manaviazar
1The School of Chemistry & Chemical Engineering and the Centre for Cancer Research and Cell Biology (CCRCB), the Queen's University Belfast , Stranmillis Road, Belfast BT9 5AG, Northern Ireland, United Kingdom.
Abstract:
The original 1967 Richardson-Hough rules for predicting SN2 displacement viability in carbohydrate sulfonate derivatives with external nucleophiles have now been updated. Not only do the original rules still hold, but the newly updated rules rationalize why O-triflates (trifluoromethanesulfonate esters) frequently allow many seemingly "disallowed" pyranosidic nucleophilic substitutions to proceed. The new guidelines, which are based on three decades of experimental evidence, allow the feasibility of many pyranosidic O-triflate SN2 displacements to be gauged beforehand.
Related Concept Videos
Nucleophilic Aromatic Substitution of Aryldiazonium Salts: Aromatic SN1
In the Sandmeyer reaction, for example, the diazonio group is replaced by a chloro, bromo,...
Preparation and Reactions of Sulfides
Factors Affecting Protein-Drug Binding: Drug Interactions
Displacement interactions can have varying outcomes, ranging from toxicity to virtually...
Diazonium Group Substitution with Halogens and Cyanide: Sandmeyer and Schiemann Reactions
Nucleophilic Aromatic Substitution: Addition–Elimination (SNAr)
The reaction begins with an attack of the nucleophile on the carbon that holds the leaving group. This results in the delocalization of the π electrons over the ring carbons. The resonance interaction between...
Nonlinear Pharmacokinetics: Dependence of Elimination Half-Life and Dose Clearance
A study on guinea pigs examined the...

