Organic Chemistry Mechanisms: A Simple Way to Approach Them
By Naeem Bukhari
Mechanisms Are Not a List — They’re a Small Set of Patterns
By the end of A Level Organic Chemistry, a student has usually met a dozen or more named mechanisms. Treated as a list to memorise individually, this feels overwhelming. Treated as a small number of recurring patterns — nucleophilic attack, electrophilic attack, curly-arrow electron movement showing where a bond forms or breaks — most new mechanisms turn out to be a variation on one already learned, not something entirely new.
Always Ask: Where Are the Electrons Actually Going?
A curly arrow represents a pair of electrons moving from one place to another — not a vague indicator of "something happening here." A student who can consistently identify the electron-rich part of a molecule (a lone pair, a pi bond, a negative charge) and the electron-poor part it’s attracted to can work out the general shape of a mechanism even for a molecule they haven't specifically seen before, which is exactly what unfamiliar exam questions test.
Draw It Every Time — Don’t Just Read It
Reading a mechanism and understanding it in the moment is not the same skill as reproducing it correctly under exam conditions. Drawing every mechanism out by hand, including the curly arrows, every single time it's revised — not just the first time — is what actually builds the ability to do it correctly and quickly in an exam.
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