Abstract: Organic reactions in the laboratory have been carried out for more than a century, but still, it is a challenge to predict the reactivity of the reagents and optimize the reaction conditions like concentration, temperature, reaction time etc. While optimizing a reaction condition to improve yields, the large quantity of starting material and time are the key leading factors. 1 Isolation of reactive/unstable intermediates and handling of toxic chemicals are also challenging in organic synthesis. The synthesis of a compound through multistep organic reactions takes more time, reagents and also poses difficulties in selectivity as well as yields. In some cases, the by-product could also be formed in larger quantities as compared to the desired product.
To overcome these difficulties a new promising technology has been developed-a continuous flow process, which involves carrying out the reaction in a continuous manner in a continuous flow reactor where the reagents are pumped simultaneously through the reactor and the product is continuously collected.2 Here micro-channel or tubes are used instead of flasks to enable the flow of the reagents to the reactor. Single and multistep organic reactions can be carried out using this technique.3 The flow rates, reaction time, reagent mixing, heat and mass transfer are the basic parameters to be optimized for successful reactions. The reaction can be monitored using UV/Vis, IR and NMR spectroscopies and mass Spectrometry attached to the continuous flow reactor system. 4, 5 In this presentation, I will describe the continuous flow reactor as a new technique for conducting multistep organic reactions with a few select examples. 6
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