Michler's ketone

Michler's ketone

Names
Preferred IUPAC name Bis[4-(dimethylamino)phenyl]methanone
Other names 4,4'-Bis(N,N-dimethylamino)benzophenone 4,4'-Bis(dimethylamino)benzophenone Bis(p-(N,N-dimethylamino)phenyl)ketone Michler ketone Michler's Ketone
Identifiers
CAS Number	90-94-8 Y
3D model (JSmol)	Interactive image
ChemSpider	6764 N
ECHA InfoCard	100.001.843
EC Number	202-027-5
KEGG	C19266 Y
PubChem CID	7031
UNII	3Z2SN6B347 Y
CompTox Dashboard (EPA)	DTXSID2020894
InChI InChI=1S/C17H20N2O/c1-18(2)15-9-5-13(6-10-15)17(20)14-7-11-16(12-8-14)19(3)4/h5-12H,1-4H3 N Key: VVBLNCFGVYUYGU-UHFFFAOYSA-N N InChI=1/C17H20N2O/c1-18(2)15-9-5-13(6-10-15)17(20)14-7-11-16(12-8-14)19(3)4/h5-12H,1-4H3 Key: VVBLNCFGVYUYGU-UHFFFAOYAE
SMILES CN(C)C1=CC=C(C=C1)C(=O)C2=CC=C(C=C2)N(C)C
Properties
Chemical formula	C17H20N2O
Molar mass	268.360 g·mol−1
Appearance	Colorless solid
Melting point	173 °C (343 °F; 446 K)
Hazards
GHS labelling:[1]
Pictograms
Signal word	Warning
Hazard statements	H318, H341, H350
Precautionary statements	P201, P280, P305+P351+P338+P310, P308+P313
Safety data sheet (SDS)	External MSDS
Related compounds
Related compounds	Benzophenone
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

Michler's ketone is an organic compound with the formula of [(CH₃)₂NC₆H₄]₂CO. This electron-rich derivative of benzophenone is an intermediate in the production of dyes and pigments, for example Methyl violet. It is also used as a photosensitizer^{[broken anchor]}.^[2] It is named after the German chemist Wilhelm Michler.

The ketone is prepared today as it was originally by Michler using the Friedel-Crafts acylation of dimethylaniline (C₆H₅NMe₂) using phosgene (COCl₂) or equivalent reagents such as triphosgene^[3]

COCl₂ + 2 C₆H₅NMe₂ → (Me₂NC₆H₄)₂CO + 2 HCl → salt

The related tetraethyl compound (Et₂NC₆H₄)₂CO, also a precursor to dyes, is prepared similarly.

Michler's ketone is an intermediate in the synthesis of dyes and pigments for paper, textiles, and leather. Condensation with various aniline derivatives gives several of the dyes called methyl violet, such as crystal violet.

Condensation of Michler's ketone with N-phenyl-1-naphthylamine gives the dye Victoria Blue B (CAS#2580-56-5, CI Basic Blue 26), which is used for coloring paper and producing pastes and inks for ballpoint pens.

Michler's ketone is commonly used as an additive in dyes and pigments as a sensitizer for photoreactions because of its absorption properties. Michler's ketone is an effective sensitizer provided energy transfer is exothermic and the concentration of the acceptor is sufficiently high to quench the photoreaction of Michler's ketone with itself. Specifically Michler's ketone absorbs intensely at 366 nm and effectively sensitizes photochemical reactions such as the dimerization of butadiene to give 1,2-divinylcyclobutane.^[4]

p-Dimethylaminobenzophenone is related to Michler's ketone, but with only one amine.^[5] Auramine O, a dye, is a salt of the iminium cation [(CH₃)₂NC₆H₄]₂CNH₂⁺. Michler's thione, [(CH₃)₂NC₆H₄]₂CS, is prepared by treatment of Michler's ketone with hydrogen sulfide in the presence of acid or sulfideing auramine O.^[6] Hydride reduction of Michler's ketone gives 4,4'-bis(dimethylamino)benzhydrol.