IB ChemistryStructure 33.23.2.12
HL

Structural Analysis

Combining data from different techniques to solve the molecular puzzle.

The Triangulation Strategy

Step 1: Mass Spec

Check the Molecular Ion peak for molar mass. Look at fragmentation to chop off pieces (e.g., loss of 15 = methyl).

Step 2: Infrared

Identify functional groups. Is there a C=O? An O-H? This tells you the "family" (e.g., ketone vs alcohol).

Step 3: NMR

Build the skeleton. Count signals (environments) and use splitting to see who is connected to whom.