Uploaded May 2026 | Updated September 2026, 2 weeks ago
Converting to a Fischer Projection on hard mode isn't about more rules: It's about more nuance. Today, we tackle the conversion of D-glucose from a skeletal structure to a Fischer projection.
When molecules reach this size, physical models begin to fall apart due to steric hindrance. (The caterpillar literally bites its own tail.) I'll show you what to do when your model kit is lagging behind and how to rely on the 5-Step System to navigate multiple chiral centers without losing a single atom.
What You'll Learn:
• The Oxidation Rule: Determining "Top" vs. "Bottom" in complex sugars.
• The Steric Fail: Why large molecules can't always achieve the "Hugging Caterpillar" confirmation.
• The Wedge/Dash Flip: Mastering the rotation of carbons at the "bottom" of the zigzag.
• The Perspective Shift: How to handle "flipped" skeletal structures on your exam.
🧬Are you currently knee-deep in chirality? That's here: youtube.com/playlist?list=PLvUW25kBaMMupOdw1Wgy8YauiQ40J_5nx
🥾Need a reaction mechanisms bootcamp? I've got you covered: youtube.com/playlist?list=PLvUW25kBaMMtvqt_IBtezyBX_kk447pxZ
🥽As an Amazon Affiliate, I earn from qualifying purchases at no extra cost to you.
🥼My recommendations: amazon.com/shop/chemnut?ccs_id=11f20bce-5f74-427b-85fb-bdf66849405a
🔬Start any shopping journey here: amzn.to/3IXuAcS
🧪Support free education & more through Patreon! patreon.com/c/ChemistryinaNutshell
0:00 Chemistry is a Foreign Language
0:08 Step 1: Pick Perspective & The Oxidation Rule
0:33 Step 2: Arch the Backbone
0:36 Molecular Model from Zig-Zag to Hugging Caterpillar
1:42 THE STERIC FAIL: Why models fall apart
2:14 Finding Carbon 1 (The Aldehyde Top)
2:19 When Models Fail...
3:04 Why Rules beat Models for large molecules
3:13 Back to Step 2
3:52 TRAP: Identifying Flipped vs Retained Stereocenters
4:23 Visualizing Wedge/Dash Flips
5:06 Steps 3 & 4: Draw the Fischer Template & Add Groups
5:17 TRAP: Dealing with Flipped Skeletal Structures
5:56 The Final Conversion: D-Glucose Summary
Citations:
Paula Yurkanis Bruice, "Organic Chemistry" 8th ed
openstax.org/details/books/organic-chemistry
openstax.org/details/books/chemistry-2e
Music: youtu.be/lL6AsbG07xY
Converting to a Fischer Projection on hard mode isn't about more rules: It's about more nuance. Today, we tackle the conversion of D-glucose from a skeletal structure to a Fischer projection.
When molecules reach this size, physical models begin to fall apart due to steric hindrance. (The caterpillar literally bites its own tail.) I'll show you what to do when your model kit is lagging behind and how to rely on the 5-Step System to navigate multiple chiral centers without losing a single atom.
What You'll Learn:
• The Oxidation Rule: Determining "Top" vs. "Bottom" in complex sugars.
• The Steric Fail: Why large molecules can't always achieve the "Hugging Caterpillar" confirmation.
• The Wedge/Dash Flip: Mastering the rotation of carbons at the "bottom" of the zigzag.
• The Perspective Shift: How to handle "flipped" skeletal structures on your exam.
🧬Are you currently knee-deep in chirality? That's here: youtube.com/playlist?list=PLvUW25kBaMMupOdw1Wgy8YauiQ40J_5nx
🥾Need a reaction mechanisms bootcamp? I've got you covered: youtube.com/playlist?list=PLvUW25kBaMMtvqt_IBtezyBX_kk447pxZ
🥽As an Amazon Affiliate, I earn from qualifying purchases at no extra cost to you.
🥼My recommendations: amazon.com/shop/chemnut?ccs_id=11f20bce-5f74-427b-85fb-bdf66849405a
🔬Start any shopping journey here: amzn.to/3IXuAcS
🧪Support free education & more through Patreon! patreon.com/c/ChemistryinaNutshell
0:00 Chemistry is a Foreign Language
0:08 Step 1: Pick Perspective & The Oxidation Rule
0:33 Step 2: Arch the Backbone
0:36 Molecular Model from Zig-Zag to Hugging Caterpillar
1:42 THE STERIC FAIL: Why models fall apart
2:14 Finding Carbon 1 (The Aldehyde Top)
2:19 When Models Fail...
3:04 Why Rules beat Models for large molecules
3:13 Back to Step 2
3:52 TRAP: Identifying Flipped vs Retained Stereocenters
4:23 Visualizing Wedge/Dash Flips
5:06 Steps 3 & 4: Draw the Fischer Template & Add Groups
5:17 TRAP: Dealing with Flipped Skeletal Structures
5:56 The Final Conversion: D-Glucose Summary
Citations:
Paula Yurkanis Bruice, "Organic Chemistry" 8th ed
openstax.org/details/books/organic-chemistry
openstax.org/details/books/chemistry-2e
Music: youtu.be/lL6AsbG07xY
