When chemical transformations have taken place historically, they have often required many steps, especially for complex molecules such as those in the field of pharmaceuticals. Each time there is a multi-step synthesis, there is the need for separation, isolation, and purification that results in loss of material, increased energy usage, and time lost.
Where possible, design for a “one-pot” synthesis, those transformations that can be carried out in a single reaction vessel that does not require isolation or other wasteful steps can result in significant efficiencies and waste reduction. These more efficient processes must also ensure not to create other problems such as utilizing increased toxic substances or generating lower quality products. When done correctly, decreased steps and decreased reaction vessels can provide significant benefits.