A journey from the
Vapourtec lab
Vapourtec managing director and founder Duncan Guthrie charts the rise and rise of flow chemistry
Figure 1 – Basic flow chemistry
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Vapourtec ’ s growth since its foundation in 2003 has mirrored that of flow chemistry . Initially , scientists translated ‘ simple ’ A + B → > C reactions to flow and photoredox-catalysed library synthesis . 1 , 2 New solutions were needed , however , to transfer batch processes to flow . By the end of the 2000s , it was clear that continuous flow would soon encompass all aspects of modern chemistry . No two applications were the same and no two systems should be the same . Otherwise , flow chemistry systems would have become too prescriptive in terms of which chemistries are possible . For that reason , our focus was on developing the most flexible and versatile flow chemistry systems , enabling telescoped reactions , photochemistry or even peptide synthesis , by just changing reactors .
Key components
When looking at a basic flow chemistry diagram , three key components define the type of reagents that can be used and the type of chemical reactions that can be carried out : 1 . Pumps to deliver reagents at a precise flow rate 2 . Reactors where reactions occur 3 . A back pressure regulator ( BPR ) to control the pressure within the reactor Reagents come in all physical states ( solid , liquid or gas ) and each must be handled differently . Gases are usually metered with mass flow controllers or peristaltic pumps ; solids are constrained in packedbed reactors ; liquids are pumped . Not all liquids are the same and not all pumps can handle them . Some reactions might require the use of fuming nitric acid ; others might need a basic reagent , such as n-butyl lithium . As time went on , users increasingly wanted to run their chemistry in extreme conditions . Soon , the need to pump corrosive chemicals , operate at extreme temperatures or use gases at ( even ) higher pressures led us to develop new systems to make these extreme chemistries possible . Vapourtec focused on the development of new pumping capabilities . Thanks to these , more reactions were successfully translated to flow , some of them proving to be easier and delivering better yields in several key areas :
• Gas / liquid reactions : Working with gas under pressure is relatively simple in flow compared to batch . To deliver gas , we integrated mass flow controllers and developed tube-in-tube reactors , allowing
54 SPECIALITY CHEMICALS MAGAZINE ESTABLISHED 1981