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Updated: Mar 20, 2026

Continuous Flow Chemistry: Reaction of Diphenyldiazomethane with p-Nitrobenzoic Acid
Published on: November 15, 2017
The pKa of Brønsted acids controls their reactivity with diazo compounds
Na Fei1, Basilius Sauter, Dennis Gillingham
1Department of Chemistry, University of Basel, St. Johanns-Ring 19, CH-4056, Basel, Switzerland. dennis.gillingham@unibas.ch.
Abstract:
We study the O-alkylation of phosphate groups by alkyl diazo compounds in a range of small molecules and biopolymers. We show that the relatively high pKa of phosphate in comparison to the other naturally occurring Brønsted acids can be exploited to control alkylation selectivity. We provide a simple protocol for chemical modification of some of the most important instances of phosphates in natural compounds including in small molecule metabolites, nucleic acids, and peptides.
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