二甲基乙内酰脲

Description

5,5-Dimethylhydantoin · CAS 77-71-4 · C5H8N2O2. UNII 34032MQ9RO. Melting Point: 178 °C; Vapor Pressure: 0.0000028 [mmHg]; LogP: log Kow = -0.48.

Identification

CAS Registry Number	77-71-4
PubChem CID	6491
Molecular formula	C5H8N2O2
IUPAC name	5,5-dimethylimidazolidine-2,4-dione
UNII (FDA)	34032MQ9RO

Computed Descriptors

Molecular Weight	128.13
XLogP3	-0.3
Hydrogen Bond Donor Count	2
Hydrogen Bond Acceptor Count	2
Rotatable Bond Count	0
Exact Mass	128.058577502
Monoisotopic Mass	128.058577502
Topological Polar Surface Area	58.2
Heavy Atom Count	9
Formal Charge	0

Physical & Chemical Properties

Melting Point	178 °C
Vapor Pressure	0.0000028 [mmHg]
LogP	log Kow = -0.48
LogP	-0.48
Dissociation Constants	pKa = 9.19
Formulations/Preparations	Reagent grade: 97%

Physical description & handling notes

• Large Crystals; Liquid
• White solid; [Hawley] White odorless crystalline powder; [Alfa Aesar MSDS]
• White, crystalline solid
• Prisms from dilute alcohol
• Sublimes
• Very soluble in ethanol, ether, acetone, benzene, chloroform; soluble in DMSO

Regulatory Status

Regulatory & Food Contact	FDA Cumulative Estimated Daily Intake (CEDI): FCS FDA Inventory of Effective Food Contact Substance (FCS) Noti: FCS 2,4-IMIDAZOLIDINEDIONE, 5,5-DIMETHYL 5,5-Dimethylhydantoin (DMH) (CAS Reg. No. 77-71-4) The FCS will be used as a stabilizer for hypohalite slimicides used in the manufacture of food-contact paper a The FCS will be used at a level not to exceed 0.5 g DMH per kg of dry fiber.
GHS notification summary	91% (252 / 277)

GHS Hazard Classification

GHS notification summary	91% (252 / 277)

Documented Uses

• Synthesis, preparation of water-soluble polymers
• Cosmetics -> Viscosity controlling; Hair conditioning
• Information on 6 consumer products that contain 5,5-Dimethyl-2,4-imidazolidinedione in the following categories is provided:
• From acetone, urea, and ammonium carbonate; from acetone, potassium cyanate and hydrocyanic acid
• 2023: 1,000,000 - <8,500,000 lb
• 2022: 1,000,000 - <8,500,000 lb

Synonyms

5,5-DIMETHYLHYDANTOIN; 77-71-4; Dimethylhydantoin; 2,4-Imidazolidinedione, 5,5-dimethyl-; Dantoin DMH; 5,5-Dimethyl-2,4-imidazolidinedione; Dantoin 736; 5,5-Dimethyl hydantoin; Hydantoin, 5,5-dimethyl-; DTXSID5021754; 34032MQ9RO; NSC-8652; DTXCID601754; RefChem:527790; 201-051-3; 5,5-dimethylimidazolidine-2,4-dione

Frequently Asked Questions

What are the CAS number and molecular formula of 5,5-Dimethylhydantoin?

CAS 77-71-4; molecular formula C5H8N2O2; molecular weight — g/mol.

What other names is 5,5-Dimethylhydantoin known by?

5,5-DIMETHYLHYDANTOIN, 77-71-4, Dimethylhydantoin, 2,4-Imidazolidinedione, 5,5-dimethyl-, Dantoin DMH, 5,5-Dimethyl-2,4-imidazolidinedione.

What is the regulatory status of 5,5-Dimethylhydantoin?

Documented regulatory listings: FDA Cumulative Estimated Daily Intake (CEDI): FCS; FDA Inventory of Effective Food Contact Substance (FCS) Noti: FCS; 2,4-IMIDAZOLIDINEDIONE, 5,5-DIMETHYL.

Is 5,5-Dimethylhydantoin classified as hazardous?

91% of GHS notifications report no hazard classification (252 of 277).

What are the key physical properties of 5,5-Dimethylhydantoin?

Melting Point: 178 °C; Vapor Pressure: 0.0000028 [mmHg]; LogP: log Kow = -0.48; LogP: -0.48.

Facts on this page are taken from PubChem (US National Library of Medicine) and Wikidata. Grade-specific data — assay, moisture, particle size, packaging, shelf life — is issued per batch on the COA and is not published here.