Accelerated reactions of amines with carbon dioxide driven by superacid at the microdroplet interface

Abstract

Microdroplets display distinctive interfacial chemistry, manifested as accelerated reactions relative to those observed for the same reagents in bulk.

Late‐Stage Functionalization and Characterization of Drugs by High‐Throughput Desorption Electrospray Ionization Mass Spectrometry

“…There was hardly any product formation at 0 h, without any time delay. Reactions in microdroplet are known to be accelerated, [28][29][30][31][32][33][34][35][36][37] however no such phenomenon was observed on the scale used here. HT-based DESI-MS analysis was also conducted to check the effect of different catalysts (Pd(acac) 2 , Pd(OAc) 2 , NiCl 2 , and CuCl 2 ) selecting the reaction between ethyl acrylate and Ezetimibe.…”

Automated High-Throughput System Combining Small-Scale Synthesis with Bioassays and Reaction Screening

“…67 This acceleration phenomenon has been linked to the unique conditions at the droplet–air interface (reaction rates increase strongly with decreasing droplet size), and not simply to the increased concentration of reagents in evaporating droplets. 65,67,86–88 Furthermore, it has been demonstrated that simply collecting the droplets sprayed from a reaction mixture allows the collection of milligram amounts of reaction product. 89 This capability confers a clear advantage for reaction screening: considerable product yields (obtained through a microdroplet-accelerated reaction) can be obtained with little to no incubation time prior to analysis.…”

Glass surface as strong base, ‘green’ heterogeneous catalyst and degradation reagent

“…We mixed the reactants at 50 µM, a condition shown to accelerate reactions to a great extent at both the air/solution 26,42,43 and solid/solution interfaces. 6,26,47,48 Figure 1 Comparison of reaction progress with glass microspheres (0.02 eq. silanolate groups, estimated) and without glass microspheres analysed by DESI-MS (average of 16 replicate analyses).…”