What is 2,4-dinitrophenylhydrazine?

What is 2,4-dinitrophenylhydrazine?

2,4-Dinitrophenylhydrazine (DNPH) is a organic chemical compound widely used as a reagent in organic chemistry to detect and identify carbonyl molecules, particularly aldehydes and ketones. It has the molecular formula C6H3NHNHCONHNH2. It appears as yellow to orange crystalline solid sparingly soluble in water but soluble in organic solvents such as ethanol, acetone, and ether....

Structure of 2,4-Dinitrophenylhydrazine

2,4-Dinitrophenylhydrazine (2,4-DNPH) structure consists of a phenyl ring with two nitro groups attached at the ortho and meta positions with a hydrazine group attached to one of the carbon atoms in the phenyl group....

Properties of 2,4-Dinitrophenylhydrazine

The properties of 2,4-Dinitrophenylhydrazine are mentioned below:...

Synthesis of the 2,4-Dinitrophenylhydrazine

2,4-Dinitrophenylhydrazine is prepared by using chlorobenzene, due to Chlorobenzene is ortho and para directing groups....

Brady’s Reagent

The aqueous solution of the DNP is known as Brady’s reagent. Brady’s reagent used primarily for the detection of aldehydes and ketones (Carbonyl compounds). It reacts with carbonyl compounds (aldehydes & ketone) to produce a coloured precipitate which confirms the carbonyl compounds....

What is 2,4-DNP Test?

The 2,4-dinitrophenylhydrazine (2,4-DNP) test is commonly used in organic chemistry labs to detect the presence of carbonyl groups (aldehydes and ketones) i.e., (C=O) functional group in organic compounds. Basically, the aqueous solution of the 2,4-Dinitrophenylhydrazine is used for the Identification of the carbonyl compounds....

Identification of a Carbonyl Compound

Brady’s reagent will be used for Identification of a Carbonyl Compounds. The carbonyl compound is simply mixed with an acid solution of Brady’s reagent in methanol....

Reaction with Ethanal

2,4-Dinitrophenylhydrazine (2,4-DNP) interacts with aldehydes and ketones to produce compounds called 2,4-dinitrophenylhydrazones....

Laboratory Test for DNP

To conduct the 2,4-dinitrophenylhydrazine test, take a test tube and add 5ml of the reagent. Next, add 10 drops of the unknown compound to the test tube and mix vigorously by tapping the test tube with a stick or finger. If the crystals do not form immediately, gently heat the test tube in a water bath at 65oC for 5 minutes. Now, cool the test tube in an ice bath until crystals form. Then, collect the crystals by vacuum filtration using a Hirsch funnel. Allow the crystals to dry on the Hirsch funnel by drawing air through them. Take note of the melting point on the Report sheet. Generally, the crystals obtained are pure enough to produce an accurate melting point. However, if the melting point range is too wide, recrystallization can be performed from a minimum volume of ethanol....

Conclusion

It’s interesting to learn that 2,4-Dinitrophenylhydrazine (2,4-DNP) has a significant role in organic chemistry, especially in identifying carbonyl compounds like aldehydes and ketones. However, it’s important to handle it with care as it is a potentially hazardous material, being both flammable and explosive. Proper storage and handling precautions should be taken to ensure safety....

Frequently Asked Questions on 2,4-Dinitrophenylhydrazine

What is 2,4-Dinitrophenylhydrazine?...