Chemistry Notes
Chemistry Notes is the working index for mechanism notes and reaction-choice guides.
Use this page when the task is to decide a mechanism, compare reaction conditions or choose a reagent.
Core routes
Section titled “Core routes”Substitution and Elimination MapFast decision route for SN1, SN2, E1 and E2 mechanism questions.Reaction TroubleshootingEvidence-led checks for low conversion, side products and unexpected TLC results.SN1 ReactionCarbocation mechanism, first-order rate law, racemisation and rearrangement traps.SN2 ReactionBackside attack, second-order rate law, inversion and steric limits.E1 and E2 EliminationBase strength, alkene selectivity, anti-periplanar geometry and rearrangement checks.Carbonyl ReductionsChoose NaBH4, LiAlH4, DIBAL-H or catalytic hydrogenation by substrate class.
How to use this section
Section titled “How to use this section”- Start with the decision map if the mechanism is unclear.
- Open the mechanism note for rate law, stereochemistry and substrate effects.
- Use the reagent pages when the question is about scope or selectivity.
- Use the troubleshooting page when observation and prediction do not match.
- Check related pages at the bottom of each note before finalising an answer.
Current gaps
Section titled “Current gaps”The next useful additions are alkene additions, aromatic substitution, carbonyl additions and spectroscopy interpretation.