Science Experiment
Science Experiment
Experiment2: Preparation of Dibenzalacetone
Using the cabon-cabon bond making ability in carbonyl chemistry, Dibenzalacetone is synthesized from 2 equivalent of benzaldehyde and 1 equivalent of acetone in a base catalyzed reaction.
Physical Data1: *detailed risk and safety phrases are attached.
substance
Hazards, risks and safety practices
MW (g/mol)
Amt. Used
mp (K)
bp (K)
density(g/cm^3)
acetone
R11, R36, R67, S9, S25, S26
58.08
0.24 g
0.004
178.2
329.4
benzaldehyde
R22, S24
106.13
0.82 g
0.008
451.1
1.0415
ehtyl acetate
R11, R36, R66, R67, S16, S26, S33
88.11
2 ml per gram
189.55
350.25
0.897
R35,S22, S26, S38, S45, S62, s24/25
39.997
0.4 g
Ethanol
R11, S2, S7, S16
46.07
158.8
351.6
0.789
Dibenzalacetone
234 g/mol
unknown
unknown
Theoretical Yield:
Limiting reagent: acetone (0.004 mol)
Presuming 100 % of limiting agent makes dibenzalacetone
Dibenzalacetone (100% yield) = 0.004 mol * 234 g/mol = 0.936 gram
The theoretical yield of dibenzalacetone is 0.936 gram
Procedures:
In a 50 ml conical flask sodium hydroxide (0.4g, 0.01 mol), distilled water (2 ml) and ethanol (2ml, 95%) were mixed into a clear solution. The solution was then cooled to room temperature. Benzaldehyde (0.8ml; 9.82g, 0.008mol) was then added to the solution followed by addition of acetone (0.3ml; 0.24g, 0.004mol) and formed into a thick yellow solution. The flask was then swirled gently and constantly for 5 minutes. This turned into a fluffy precipitate as the flask was swirled. After 5 minutes