Green chemistry: yield, atom economy and waste are not interchangeable
Compare a synthesis using more than one metric, and state which materials and process boundaries your assessment includes.
One favourable number is not a verdict
A high yield does not alone establish the greenest process. Solvents, excess reagents, separation, energy and hazards also matter. State whether your comparison includes only the reaction or also preparation and purification. Different boundaries can produce numbers that should not be directly compared.
Separate atom economy from yield
Atom economy evaluates how reactant atoms can enter the desired product from the reaction stoichiometry. It differs from experimental yield. A reaction can have attractive atom economy but poor practical conversion, or the reverse.
Neither a high atom economy nor low waste alone proves low toxicity or low acute hazard. Each metric addresses part of the decision.
Make a useful comparison
Material-use metrics need a clear definition of what is counted, including whether water, solvents and processing aids are included. Pair the numbers with the method and assumptions.
Compare routes by accessibility, step count, material demand, energy and hazards. Explain which tradeoff suits the situation instead of turning one metric into a universal winner.
