Uploaded April 2026 | Updated September 2026, 2 weeks ago
Can you go from 3D to 2D without losing atoms or flipping your R/S conformation at a chiral center? Converting a perspective formula (wedge-and-dash structure) back into a skeletal structure (line structure) is a high-frequency exam question that trips up students who try to "guess" the zig-zag.
In this video, I'll show you how to "flatten" the molecule properly. We'll use molecular models to visualize the bond rotation between conformations, ensuring you never flip a substituent or lose a carbon in the process.
I've graded thousands of organic chemistry exams, and I'm sharing the exact "audit method" I teach my students to verify their structures before they hand in their papers.
What we cover:
• The "Eye" Placement: Where to look to make the conversion easy
• The 3D to 2D Collapse: Mapping wedges and dashes onto a flat plane
• Pro-Tip: How to handle "hidden" hydrogens when they aren't drawn
• Walkthrough: A step-by-step conversion of 2,3-dibromobutane into 2 conformations
Related Units:
Studying chirality and stereochem next? You'll want this: youtube.com/playlist?list=PLvUW25kBaMMupOdw1Wgy8YauiQ40J_5nx
Need help with reaction mechanisms? That's here: 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 The Perspective Formula (Wedge-and-Dash Structure)
0:49 Visualizing 2,3-Dibromobutane in 3D
1:03 Decoding Wedges and Dashes
1:20 Step 1: Drawing the Carbon Backbone
1:40 Exam Trap 1: The Extra Carbon Trap
2:11 Step 2: Placing Substituents (Br)
2:43 Exam Trap 2: The R/S Flip
3:03 Carbon 2 R/S Audit
4:06 Carbon 3 R/S Audit
5:02 Visualizing the Most & Least Conformations of 2,3-Dibromobutane in 3D
6:04 For Full Credit, Clean Up the Drawings!
6:10 Exam Trap 3: The Wedge and Dash Flip Trap
6:54 R/S Audit After a Bond Rotation
7:29 The Secret to Newman Projections
Citations:
Paula Yurkanis Bruice, "Organic Chemistry" 8th ed
openstax.org/details/books/organic-chemistry
openstax.org/details/books/chemistry-2e
Music: youtu.be/lL6AsbG07xY
Can you go from 3D to 2D without losing atoms or flipping your R/S conformation at a chiral center? Converting a perspective formula (wedge-and-dash structure) back into a skeletal structure (line structure) is a high-frequency exam question that trips up students who try to "guess" the zig-zag.
In this video, I'll show you how to "flatten" the molecule properly. We'll use molecular models to visualize the bond rotation between conformations, ensuring you never flip a substituent or lose a carbon in the process.
I've graded thousands of organic chemistry exams, and I'm sharing the exact "audit method" I teach my students to verify their structures before they hand in their papers.
What we cover:
• The "Eye" Placement: Where to look to make the conversion easy
• The 3D to 2D Collapse: Mapping wedges and dashes onto a flat plane
• Pro-Tip: How to handle "hidden" hydrogens when they aren't drawn
• Walkthrough: A step-by-step conversion of 2,3-dibromobutane into 2 conformations
Related Units:
Studying chirality and stereochem next? You'll want this: youtube.com/playlist?list=PLvUW25kBaMMupOdw1Wgy8YauiQ40J_5nx
Need help with reaction mechanisms? That's here: 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 The Perspective Formula (Wedge-and-Dash Structure)
0:49 Visualizing 2,3-Dibromobutane in 3D
1:03 Decoding Wedges and Dashes
1:20 Step 1: Drawing the Carbon Backbone
1:40 Exam Trap 1: The Extra Carbon Trap
2:11 Step 2: Placing Substituents (Br)
2:43 Exam Trap 2: The R/S Flip
3:03 Carbon 2 R/S Audit
4:06 Carbon 3 R/S Audit
5:02 Visualizing the Most & Least Conformations of 2,3-Dibromobutane in 3D
6:04 For Full Credit, Clean Up the Drawings!
6:10 Exam Trap 3: The Wedge and Dash Flip Trap
6:54 R/S Audit After a Bond Rotation
7:29 The Secret to Newman Projections
Citations:
Paula Yurkanis Bruice, "Organic Chemistry" 8th ed
openstax.org/details/books/organic-chemistry
openstax.org/details/books/chemistry-2e
Music: youtu.be/lL6AsbG07xY
