As part of our ongoing series of application notes on pumping slurries of reagents we have turned our attention to sodium hydride, one of the most versatile heterogeneous strong bases.
This application note describes a Vapourtec E-series easy-MedChem:
– Utilising sodium hydride slurries in a laboratory scale continuous flow reaction
– Pumping the sodium hydride as a slurry and controlling gas formation by operation at a pressure of 7 bar
– Truly continuous operation demonstrated during a 2-hour synthesis of an alkyl carbazole heterocyclic intermediate
– Fast reaction time of 4 minutes
– 82 % isolated yield, 10.6 gh-1 with greater than 98% purity
As shown previously, the Vapourtec V-3 pumps are capable of handling high density slurries both as pumps and pressure regulators. We believe that access to such a useful strong base in continuous flow can enable the synthetic chemist to perform a wider range of syntheses continuously, gaining both the advantages over the reaction environment, but also in the safety of only having a small volume of such a reactive species under reaction conditions, and perhaps crucially to quench, at any one time.