Naphtholactam

Naphtholactam
Names
	Preferred IUPAC name Benzo[cd]indol-2(1H)-one
	Other names 1,8-naphtholactam
Identifiers
CAS Number	130-00-7;
3D model (JSmol)	Interactive image;
ChEMBL	ChEMBL217045;
ChemSpider	60558;
ECHA InfoCard	100.004.523
EC Number	204-973-4;
PubChem CID	67222;
CompTox Dashboard (EPA)	DTXSID5059610 ;
	InChI InChI=1S/C11H7NO/c13-11-8-5-1-3-7-4-2-6-9(12-11)10(7)8/h1-6H,(H,12,13) Key: GPYLCFQEKPUWLD-UHFFFAOYSA-N;
	SMILES C1=CC2=C3C(=C1)C(=O)NC3=CC=C2;
Properties
Chemical formula	C11H7NO
Molar mass	169.183 g·mol−1
Appearance	white solid
Melting point	181 °C (358 °F; 454 K)
Hazards
	GHS labelling:
Pictograms
Signal word	Warning
Hazard statements	H302
Precautionary statements	P264, P270, P301+P312, P330, P501
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Naphtholactam is an organic compound derived from naphthalene. It is a tricyclic species consisting of a naphthalene core fused with a lactam (NH-CO-) at the 1,8-positions. The N-alkyl derivatives are commercially important.

Dye precursor

It is a precursor to the dye anthanthrone via ring-opening to the amino carboxylic acid, which can be converted to the diazonium salt. Naphthostyril derivatives are also of interest in medicinal chemistry.^[1] Naphthostyrils can be produced by metal-catalyzed cyclization of 1-naphthylamides.^[2]

Chemical structure of typical naphtholactam dye.

N-Ethylnaphtholactam and related derivatives are precursors to many dyes. The lactam condenses with anilines in the presence of phosphorus oxychloride.^[3]

References

^ López-Rodríguez, María L.; Porras, Esther; Morcillo, M. José; Benhamú, Bellinda; Soto, Luis J.; Lavandera, José L.; Ramos, José A.; Olivella, Mireia; Campillo, Mercedes; Pardo, Leonardo (2003). "Optimization of the Pharmacophore Model for 5-HT7R Antagonism. Design and Synthesis of New Naphtholactam and Naphthosultam Derivatives". Journal of Medicinal Chemistry. 46 (26): 5638–5650. doi:10.1021/jm030841r. hdl:10637/5547. PMID 14667218.
^ Ying, Jun; Fu, Lu-Yang; Zhong, Guoqiang; Wu, Xiao-Feng (2019). "Cobalt-Catalyzed Direct Carbonylative Synthesis of Free (NH)-Benzo[cd]indol-2(1H)-ones from Naphthylamides". Organic Letters. 21 (14): 5694–5698. doi:10.1021/acs.orglett.9b02037. PMID 31246481.
^ Berneth, Horst (2008). "Methine Dyes and Pigments". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a16_487.pub2. ISBN 978-3527306732.

[1] López-Rodríguez, María L.; Porras, Esther; Morcillo, M. José; Benhamú, Bellinda; Soto, Luis J.; Lavandera, José L.; Ramos, José A.; Olivella, Mireia; Campillo, Mercedes; Pardo, Leonardo (2003). "Optimization of the Pharmacophore Model for 5-HT7R Antagonism. Design and Synthesis of New Naphtholactam and Naphthosultam Derivatives". Journal of Medicinal Chemistry. 46 (26): 5638–5650. doi:10.1021/jm030841r. hdl:10637/5547. PMID 14667218.

[2] Ying, Jun; Fu, Lu-Yang; Zhong, Guoqiang; Wu, Xiao-Feng (2019). "Cobalt-Catalyzed Direct Carbonylative Synthesis of Free (NH)-Benzo[cd]indol-2(1H)-ones from Naphthylamides". Organic Letters. 21 (14): 5694–5698. doi:10.1021/acs.orglett.9b02037. PMID 31246481.

[3] Berneth, Horst (2008). "Methine Dyes and Pigments". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a16_487.pub2. ISBN 978-3527306732.

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