User:Stone/Benzaldehyde
From Wikipedia, the free encyclopedia
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| Other names | 2,2’-Bis(2,3-dihydro-3-oxoindolyliden) Indigotin |
| Identifiers | |
| CAS number | [482-89-3 or 12626-73-2] |
| RTECS number | DU2988400 |
| SMILES | O=c3c(=c2[nH]c1ccccc1c2=O)[nH]c4ccccc34 |
| Properties | |
| Molecular formula | C16H10N2O2 |
| Molar mass | 262.27 g/mol |
| Appearance | dark blue crystalline powder |
| Density | 1.199 g/cm3 |
| Melting point |
390-392°C |
| Solubility in water | unsoluable at 20 °C |
| Hazards | |
| EU classification | 207-586-9 |
| R-phrases | R36/37/38 |
| S-phrases | S26-S36 |
| Related compounds | |
| Related compounds | Indoxyl Tyrian purple Indican |
| Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references |
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’’’Benzaldehyde’’’ C7H6O, is a colourless liquid and the simplest aromatic aldehyde. The characteristic and pleasant almond-like odor of benzaldehyde makes it an important food ingredient, artifical flavour and as ingredient for perfumes. It is the primary component of bitter almond oil extract, and can be extracted from a number of other natural sources, such as apricot, cherry, and laurel leaves, peach seeds and, in a glycoside combined form (amygdalin), in certain nuts and kernels. Currently benzaldehyde is primarily made from toluene by a number of different processes.
On oxidation, for example if in contact with air, benzaldehyde is converted into benzoic acid. On reduction, benzyl alcohol can be formed, transition metal catalysed hydrogenation or metal hydrides are used for this purpose.
In basic conditions, potassium or sodium hydroxide for example, a reduction and oxidation process (disproportionation) occurs, which results in the production of potassium benzoate and benzyl alcohol. This Cannizzaro's reaction is a common reaction for aromatic aldehydes. The speed of this reaction depends on the substituents present on the aromatic ring. Because of air oxidation and the Cannizzaro reaction, benzaldehyde always contains small amounts of benzoic acid and benzyl alcohol, which can be separated by fractional distillation.
[edit] Biology
almonds apricot, apple and cherry kernels, contain significant amounts of (amygdalin). This glycoside breaks down under enzyme catalysis into benzaldehyde, hydrocyanic acid and two molecules of glucosis.
