CAS No 2682-20-4 , 2-methyl-1,2-thiazol-3-one

Title: Methylisothiazolinone
CAS Registry Number: 2682-20-4
CAS Name: 2-Methyl-3(2H)-isothiazolone
Synonyms: MI; MIT
Trademarks: Neolone 950 (Rohm & Haas)
Molecular Formula: C4H5NOS
Molecular Weight: 115.15
Percent Composition: C 41.72%, H 4.38%, N 12.16%, O 13.89%, S 27.85%
Literature References: Marketed in combination with methylchloroisothiazolinone as a broad spectrum biocide. Prepn: W. D. Crow, N. J. Leonard, Tetrahedron Lett. 5, 1477 (1964); eidem, J. Org. Chem. 30, 2660 (1965); S. N. Lewis et al., J. Heterocycl. Chem. 8, 571 (1971). HPLC determn in cosmetic products: R. Matissek, Chromatographia 28, 34 (1989). In vitro neurotoxicity study: S. Du et al., J. Neurosci. 22, 7408 (2002). Safety assessment: J. Am. Coll. Toxicol. 11, 75-128 (1992). Review of epidemiology of allergic reactions: A. C. de Groot, J. W. Weyland, J. Am. Acad. Dermatol. 18, 350-358 (1988) J. Fewings, T. Menné, Contact Dermatitis 41, 1-13 (1999).
Properties: Colorless prisms, mp 50-51°. bp0.03 93°. uv max (diethyl ether): 281 nm (e 6550). uv max (95% ethanol): 275 nm (e 7250).
Melting point: mp 50-51°
Boiling point: bp0.03 93°
Absorption maximum: uv max (diethyl ether): 281 nm (e 6550); uv max (95% ethanol): 275 nm (e 7250)
 
Derivative Type: Methylchloroisothiazolinone
CAS Registry Number: 26172-55-4
CAS Name: 5-Chloro-2-methyl-3(2H)-isothiazolone
Synonyms: MCI
Molecular Formula: C4H4ClNOS
Molecular Weight: 149.60
Percent Composition: C 32.11%, H 2.70%, Cl 23.70%, N 9.36%, O 10.69%, S 21.43%
Properties: Crystals from ligroin (60-90°), mp 54-55°. uv max (methanol): 277 nm (log e 3.82).
Melting point: mp 54-55°
Absorption maximum: uv max (methanol): 277 nm (log e 3.82)
 
Derivative Type: Mixture with methylchloroisothiazolinone
CAS Registry Number: 55965-84-9
Trademarks: Kathon CG (Rohm & Haas)
Properties: Commercial product is supplied as a clear, light amber liquid, fp -18° to -21.5°. d20 1.19. Viscosity (23°): 5.0 ±0.2 cP. Readily misc in water, lower alcohols, glycols, other hydrophilic organic solvents. Insol in petrolatum. LD50 (mg/kg) orally in rabbits: 30; i.p. in male, female rats: 4.6, 4.3. LC50 (6 day) in trout, sunfish (mg/l): 0.14, 0.54. LC50 (8 day dietary) in Bobwhite quail, Peking duck (mg/kg/day): >60, >100 (J. Am. Coll. Toxicol.).
Density: d20 1.19
Toxicity data: LD50 (mg/kg) orally in rabbits: 30; i.p. in male, female rats: 4.6, 4.3; LC50 (6 day) in trout, sunfish (mg/l): 0.14, 0.54; LC50 (8 day dietary) in Bobwhite quail, Peking duck (mg/kg/day): >60, >100 (J. Am. Coll. Toxicol.)
 
Use: Antimicrobial preservative in cosmetics, hygeine products, paints, emulsions, cutting oils, paper coatings, and water storage and cooling units.