Diphenylketene

Diphenylketene

Names
IUPAC name 2,2-Di(phenyl)ethenone
Other names Diphenylethenone
Identifiers
CAS Number	525-06-4 Y
3D model (JSmol)	Interactive image Interactive image
ChemSpider	109691 Y
PubChem CID	123069
InChI InChI=1S/C14H10O/c15-11-14(12-7-3-1-4-8-12)13-9-5-2-6-10-13/h1-10H Y Key: ZWJPCOALBPMBIC-UHFFFAOYSA-N Y InChI=1/C14H10O/c15-11-14(12-7-3-1-4-8-12)13-9-5-2-6-10-13/h1-10H Key: ZWJPCOALBPMBIC-UHFFFAOYAQ
SMILES C1=CC=C(C=C1)C(=C=O)C2=CC=CC=C2 O=C=C(c1ccccc1)c2ccccc2
Properties
Chemical formula	C14H10O
Molar mass	194.23 g·mol−1
Appearance	Red-orange oil
Melting point	8 to 9 °C (46 to 48 °F; 281 to 282 K)
Boiling point	118 to 120 at 1mmHg
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Y  (what is YN ?)
Infobox references

Diphenylketene is a chemical substance of the ketene family. Diphenylketene, like most disubstituted ketenes, is a red-orange oil at room temperature and pressure. Due to the successive double bonds in the ketene structure R¹R²C=C=O, diphenyl ketene is a heterocumule. The most important reaction of diphenyl ketene is the [2+2] cycloaddition at C-C, C-N, C-O, and C-S multiple bonds.

Diphenyl ketene was first isolated by Hermann Staudinger in 1905 and identified as the first example of the exceptionally reactive class of ketenes with the general formula R¹R²C=C=O (R¹=R²=phenyl group).

The first synthesis by H. Staudinger was based on 2-chlorodiphenylacetyl chloride (prepared from hydroxy(diphenyl)acetic acid and thionyl chloride) from which two chlorine atoms are cleaved with zinc in a dehalogenation reaction:

An early synthesis uses benzilmonohydrazone (from Diphenylethanedione and hydrazine hydrate), which is oxidized with mercury(II)oxide and calcium sulfate to form mono-diazoketone, and is then converted into the diphenylketene at 100 °C under nitrogen elimination in 58% yield:

A further early diphenylketene synthesis originates from Eduard Wedekind, who had already obtained diphenyl ketene in 1901 by the dehydrohalogenation of diphenylacetyl chloride with triethylamine, without isolation and characterization though. This variant was also described in 1911 by H. Staudinger.