SECTION 1 - ALIPHATIC
Aldehydes and ketones
|Type of reaction |Mechanism |
|1. oxidation (aldehydes only): aldehyde ( carboxylic acid |n/a |
| | |
|reagents: potassium dichromate (K2Cr2O7) in sulphuric acid (H2SO4) | |
|conditions: warm under reflux | |
|equation: R-CHO + [O] ( R-COOH | |
|observation: orange to green | |
| | |
|to distinguish between aldehydes and ketones: | |
|either: | |
|add Fehling’s solution and heat | |
|observation: blue solution to brick red precipitate | |
|equation: R-CHO + 4OH- + 2Cu2+ ( R-COOH + Cu2O + 2H2O | |
|or: | |
|add Tollen’s reagent and