📋 Workflow
Full workflow, products add-to-cart directly1
Substrate prep and drying
30 minDissolve hydroxyl/amine substrate in dry THF, dry over 3Å molecular sieves, purge with N₂ three times.
💡 Tip Strict anhydrous and O₂-free handling boosts yield
⚠️ Caution Moisture deactivates the protecting reagent
🧪 Materials for this step (click to shop by spec/brand)
2
Introduce the protecting group
2–3 hAdd the protecting reagent (e.g. Boc-anhydride) dropwise at 0℃, stir until starting material disappears by TLC.
💡 Tip Add reagent in portions to control exotherm
⚠️ Caution Boc formation releases CO₂; add slowly
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3
Monitor and workup
1–2 hTrack to completion by TLC, quench with water, extract with EtOAc, dry over Na₂SO₄, concentrate.
💡 Tip Use a fresh stain to visualize protected product
⚠️ Caution Do not over-concentrate too long
🧪 Materials for this step (click to shop by spec/brand)
4
Deprotection and purification
2–3 hDeprotect Boc with TFA at low temperature, concentrate, and purify by column chromatography.
💡 Tip Add a scavenger like TIPS to trap by-products
⚠️ Caution TFA is corrosive; work in a fume hood
🧪 Materials for this step (click to shop by spec/brand)
⚠️ 5 Common Beginner Mistakes
- ① Water in system hydrolyzes the reagent
- ② Rapid addition overheats and destroys product
- ③ Not monitoring side products reduces purity
- ④ Deprotection too harsh removes other groups
- ⑤ Stale drying agent leaves moisture
❓ FAQ
+How to choose a protecting group?
Choose one that is orthogonal, stable under your conditions, and easily removed.
+Alternatives to TFA for Boc removal?
HCl in dioxane or mild acid catalysis works too.
+Why add a scavenger?
It traps tert-butyl cations that would otherwise attack the substrate.