Automated synthesis
Applications of automated synthesis are found on research and industrial scales in a wide variety of fields including polymers, personal care, and radiosynthesis.
However, human revision is usually still required to ensure the automated route is practical and there are no implicit steps or conditions missing from the proposed procedure.
[3] Automation of synthesis has three main benefits: increased efficiency, quality (yields and purity), and safety, all resulting from decreased human involvement.
Automated synthesis workflows are needed both in academic research and a wide array of industrial R&D settings (pharmaceuticals, agrochemicals, fine & specialty chemicals, renewables & energy research, catalysts, polymers, ceramics & abrasives, porous materials, nanomaterials, biomaterials, lubricants, paints & coatings, home care, personal care, nutrition, forensics).
With automated synthesis, General electric manufactured an approach for melt-polymerizations of BPA and diphenyl carbonate (DPC), using sodium hydroxide (NaOH) as the catalyst.
[15] Once the results were analyzed, it was shown that, by using an automated method of polymerization, the effect of varying the catalyst amount became more distinct and improved the reproducibility for the reaction.
These methods have been used within reversible addition-fragmentation transfer (RAFT), atom-transfer radical (ATRP), and nitroxide-mediated polymerizations, demonstrating the ability of robots to improve efficiency and reduce the hardship of performing reactions.
For example, Hoogenboom et al. determined the optimal temperature for the polymerization of 2-ethyl-2-oxazoline in dimethylacetamide (DMAc), allowing for individual heating of the parallel reactors, which shortened the time needed for preparation and analysis.
[12] This process found that the largest polyethylene polymers were created by the complexes with the highest steric hindrance for the ortho-positions of the aryl rings, while electronic factors did not influence yield or molecular weight.
[12] From this, it was revealed that classical laboratory approaches could be transferred to automatic synthesis, optimizing the processes to increase efficiency and aid with reproducibility.
[12] Over the years, multiple synthesizers have been developed to assist with automated synthesis, including the Chemspeed Accelerator (SLT106, SLT II, ASW2000, SwingSLT, Autoplant A100, and SLT100), the Symyx system, and Freeslate ScPPR.
[13] This research has led to the development of oxygen-tolerant CLRP, including with the use of enzyme degassing of RAFT (Enz-RAFT), atom-transfer radical (ATRP) that possesses tolerance to air, and photoinduced electron/energy transfer–RAFT (PET–RAFT) polymerization.
[13] Through the use of liquid-handling robots, Tamasi et al. demonstrated the use of automated synthesis with executing multi-step procedures, enabling the reactions to investigate more elaborate schemes, such as with scale and complexity.
[22] Conditions of reactions (atmosphere, temperature, pressure) are controlled with the help of peripherals like: gas cylinders, vacuum pump, reflux system and cryostat.
