What is so special about benzaldehyde?

[ssb]

Someone asked me this today and I didnt know what to tell them other than the carbonyl group is stabelized really well with the benzene ring. Anything else really special about it?

 

[ShawnD]

It's special because it smells like almonds.

 

[ssb]

It's special because it smells like almonds.

Uh oh i always run out of the lab when I smell that! I am afraid of C tripple bond N groups

 

[ssb]

Why does this silly thing do a double post when ever I come back to check for replies? dang nabit

 

[Shadowz]

It is the simplest representative of the aromatic aldehydes and one of the most industrially used members of this family of compounds. It is used chiefly in the synthesis of other organic compounds

 

[ShawnD]

Uh oh i always run out of the lab when I smell that! I am afraid of C tripple bond N groups

Huh? I don't think benzaldehyde even has a nitrogen

 

[chemisttree]

But cyanide (HCN) does smell like almonds as well...

 

[ShawnD]

I always wonder how people know things like that. It's like asking "how does it feel to have your face run over by a lawn mower?" The only guy who knows is the guy who can't tell you... because he's dead

 

[chemisttree]

One fairly common use for benzaldehyde is to make benzoic acid. The sodium salt is sodium benzoate, a food preservative in almost every low pH prepared food (including soda).

In a school teaching lab it can be used as an example of an aldehyde that makes wonderful 2,4-DNP crystals and beautiful silver mirrors (Tollen's test) but does not give an iodoform reaction. The carbonyl is present (by IR test) but it is different in position from ketones and carboxylic acids. It can be oxidized to benzoic acid in one lab session and recrystallized in another demonstrating a common chemical transformation and a useful purification methodology. It is fairly non-toxic, always a plus, so is appropriate for use in a lab full of first time organic chemists. It has a UV chromophore enabling its use to demonstrate thin layer chromatography with UV visualization (vs iodine or acid char - DANGEROUS!). And it smells nice and won't empty out the building in the event of a spill.

That's all pretty special in my opinion...