874-14-6

Basic information

• Product Name: 1,3-Dimethyluracil
• Synonyms: TIMTEC-BB SBB004164;3h)-pyrimidinedione,1,3-dimethyl-4(1h;N,N'-Dimethyluracil;N1,N3-Dimethyluracil;Uracil, 1,3-dimethyl-;1,3-dimethyl-2,4-pyrimidinedione;1,3-dimethylpyrimidine-2,4-dione;1,3-Dimethyl-2,4(1H,3H)-pyrimidinedione, 2,4-Dihydroxy-1,3-dimethylpyrimidine
• CAS NO: 874-14-6
• Molecular Formula: C₆H₈N₂O₂
• Molecular Weight: 140.14
• EINECS: 212-856-4
• Product Categories: Pyridines, Pyrimidines, Purines and Pteredines;NULL
• Mol File: 874-14-6.mol

Chemical Properties

• Melting Point: 119-122 °C(lit.)
• Boiling Point: 256.63°C (rough estimate)
• Flash Point: 84.3 °C
• Appearance: white to light yellow needles
• Density: 1.2850 (rough estimate)
• Vapor Pressure: 0.214mmHg at 25°C
• Refractive Index: 1.5010 (estimate)
• Storage Temp.: Sealed in dry,Room Temperature
• PKA: -2.04±0.20(Predicted)
• Water Solubility: almost transparency
• BRN: 124074
• CAS DataBase Reference: 1,3-Dimethyluracil(CAS DataBase Reference)
• NIST Chemistry Reference: 1,3-Dimethyluracil(874-14-6)
• EPA Substance Registry System: 1,3-Dimethyluracil(874-14-6)

Safety Data

• Hazard Codes: Xi
• Statements: 36-36/37/38
• Safety Statements: 22-24/25-39-26-36/37
• WGK Germany: 3
• TSCA: Yes
• Hazardous Substances Data: 874-14-6(Hazardous Substances Data)

Usage

Uses

Used in Chemical Research:
1,3-Dimethyluracil is used as a suitable reagent for investigating the steady-state absorption and fluorescence spectra of uracil derivatives. This application aids in understanding the properties and behavior of these compounds, which can be crucial for further research and development in the field of chemistry.
Used in Pharmaceutical Industry:
1,3-Dimethyluracil is used in the preparation of 2,6-dihydroxynicotinamide, a compound that may have potential applications in the pharmaceutical industry. Its role in the synthesis of such bioactive molecules highlights its importance as a building block in drug development processes.

Purification Methods

Crystallise it from EtOH/ether. [Beilstein 24 III/IV 1196.]

InChI:InChI=1/C6H8N2O2/c1-7-4-3-5(9)8(2)6(7)10/h3-4H,1-2H3

Upstream product

• 186581-53-3 diazomethane 
• 66-22-8 uracil 
• 3551-55-1 2,4-dimethoxypyrimidine 
• 6972-27-6 1,3-Dimethyl-6-chlorouracil 
• 7152-66-1 1-methyl-4-methoxy-2-oxo-1,2-dihydropyrimidine 
• 77-78-1 dimethyl sulfate 
• 120-72-9 indole 
• 4869-46-9 1,3-dimethyl-2,4-dioxo-1,2,3,4-tetrahydro-pyrimidine-5-carbaldehyde 
• 141-90-2 2-thiouracil 
• 17237-74-0 (4aR*,4bS*,8aS*,8bR*)-1,3,6,8-tetramethylhexahydrocyclobuta[1,2-d:4,3-d']dipyrimidine-2,4,5,7(3H,6H)-tetraone 
• 49785-67-3 1,3-dimethyl-4-thiouracil 
• 109-80-8 1.3-propanedithiol 
• 7033-39-8 5-bromo-1,3-dimethyluracil 
• 91-16-7 1,2-dimethoxybenzene 

Downstream Products

• 49785-67-3 1,3-dimethyl-4-thiouracil 
• 64359-56-4 1,3-dimethyl-2,4-dithiouracil 
• 20406-86-4 1,3-dimethyl-5-hydroxyuracil 
• 7033-39-8 5-bromo-1,3-dimethyluracil 
• 926-61-4 3-oxopropanoic acid 
• 100651-92-1 1,3-dimethyl-5-<(E)-2-phenylethenyl>uracil 
• 787-84-8 N'-benzoylbenzohydrazide 
• 75029-44-6 1,3-dimethyl-5-benzoylpyrimidine-2,4(1H,3H)-dione 
• 75029-38-8 5-(2-Chlorbenzoyl)-1,3-dimethyluracil-(2-chlorbenzoyl)hydrazon 
• 65-85-0 benzoic acid 
• 135073-84-6 3-(2,6-Dichloro-phenyl)-5,7-dimethyl-7,7a-dihydro-3aH-isoxazolo[5,4-d]pyrimidine-4,6-dione 
• 135073-83-5 1,3-Dimethyl-5-(2,6-dichlorobenzoyl)uracil oxime 
• 135073-85-7 1,3-Dimethyl-5-(4-chlorobenzoyl)uracil oxime 
• 135067-69-5 1,3-dimethyl-5-(phenylselanyl)pyrimidine-2,4(1H,3H)-dione 

Relevant articles and documents

Photocatalytic Oxidative [2+2] Cycloelimination Reactions with Flavinium Salts: Mechanistic Study and Influence of the Catalyst Structure

Flavinium salts are frequently used in organocatalysis but their application in photoredox catalysis has not been systematically investigated to date. We synthesized a series of 5-ethyl-1,3-dimethylalloxazinium salts with different substituents in the positions 7 and 8 and investigated their application in light-dependent oxidative cycloelimination of cyclobutanes. Detailed mechanistic investigations with a coumarin dimer as a model substrate reveal that the reaction preferentially occurs via the triplet-born radical pair after electron transfer from the substrate to the triplet state of an alloxazinium salt. The very photostable 7,8-dimethoxy derivative is a superior catalyst with a sufficiently high oxidation power (E=2.26 V) allowing the conversion of various cyclobutanes (with Eox up to 2.05 V) in high yields. Even compounds such as all-trans dimethyl 3,4-bis(4-methoxyphenyl)cyclobutane-1,2-dicarboxylate can be converted, whose opening requires a high activation energy due to a missing pre-activation caused by bulky adjacent substituents in cis-position.

Decarboxylation of orotic acid analogues: Comparison of solution and gas-phase reactivity

The decarboxylation of orotic acid and analogues have been investigated as a model for enzymatic decarboxylation catalyzed by orotidine-5′-monophosphate decarboxylase (ODCase). The rate of decarboxylation of 1-methyl-4-pyridone-2-carboxylic acid in solution has been reported to be three orders of magnitude greater than those of 1,3-dimethylorotic acid and 1-methyl-2-pyridone-6-carboxylic acid in solution. Here, the gas-phase decarboxylation of the three corresponding carboxylates were investigated. The carboxylate of 1,3-dimethylorotic acid decarboxylates at a faster rate and thus the relative rates of decarboxylation are different from those observed in solution. The relative rates of decarboxylation correlate well with the stability of the corresponding carbanions and the calculated activation energies for gas-phase decarboxylation. Therefore, the reactions in the gas phase seem to go through the direct decarboxylation mechanism whereas the reactions in solution likely go through zwitterionic intermediates as previously proposed.

Iodine/persulfate-promoted site-selective direct thiolation of quinolones and uracils

A simple and general method for direct thiolation of 4-quinolones with disulfides or thiols under I2/K2S2O8 system has been developed. Under the optimal conditions, the C–S bond coupling can take place effectively with good to decent yields and excellent regioselectivity of the S-linked products. The established metal-free site-selective approach was also applicable to transform a range of uracil substrates to the thio-substituted products under mild conditions. Further transformation to the sulfone derivatives can be conveniently performed in one-pot. These easy-to-handle protocols represent a useful and interesting synthetic alternative with good substrate scope and functional group compatibility.

Copper-Catalyzed Regioselective Direct C–H Thiolation and Thiocyanation of Uracils

A novel copper-catalyzed direct C–H thiolation and thiocyanation of uracils using disulfides and thiocyanate salts respectively as coupling partners are described. These reactions enable the C–H bond cleavage and C–S bond formation to proceed efficiently under relatively mild conditions, providing useful methods for a preparation of a series of thio-substituted at the C5 position of uracil derivatives. These protocols exhibit several merits including simple experimental procedures, readily accessible substrates and reagents, broad scopes, high yields, and excellent regioselectivity. Preliminary mechanistic studies revealed that a radical pathway is likely to be involved.

Photocatalytic Systems with Flavinium Salts: From Photolyase Models to Synthetic Tool for Cyclobutane Ring Opening

Two new photocatalytic systems based on flavinium species formed in situ by protonation of riboflavin-tetraacetate (1) with triflic acid or prepared in advance via alloxazine quaternization are presented as effective tools for oxidative cyclobutane ring [2 + 2] cycloreversion using visible light. The system with 1,3-dimethyl-8-trifluoromethylalloxazinium perchlorate (2c) was found to be superior allowing an acid-free mild procedure, which results in the opening of cyclobutanes with high oxidation potential (up to 2.14 V) and/or with sensitive groups (e.g., furan) without side reactions.

Synthesis of 5-hetaryluracil derivatives via 1,3-dipolar cycloaddition reaction

1,3-Dipolar cycloaddition is a convenient method for construction of various heterocyclic systems. We applied this method for the synthesis 5-hetaryluracil derivatives where substituted uracils played the role of 1,3-dipoles or dipolarophiles. Treatment of the nitrile oxide derived from 5-formyluracil and substituted alkenes gave the appropriate 5-(4,5-dihydroisoxazol-3-yl)pyrimidine-2,4(1H,3H)-diones, which by oxidation with N-bromosuccinimide were transformed into appropriate 5-(isoxazol-3-yl)uracils. When 5-cyanouracil was used as a dipolarophile in the reaction with nitrile oxides, generated from aromatic aldoximes, several 5-(1,2,4-oxadiazol-5-yl)uracils were obtained. An alternative reaction of 5-formyluracil with an excess of nitriles in the presence of cerium ammonium nitrate as an oxidant gave 1,2,4-oxadiazol-3-yl derivatives in moderate yields. (Chemical Equation Presented).

C-H trifluoromethylations of 1,3-dimethyluracil and reactivity of the products in C-H arylations

Diverse electrophilic, nucleophilic and radical C-H trifluoromethylations of 1,3-dimethyluracil were systematically studied in order to prepare either 5- or 6-(trifluoromethyl)uracil derivatives. Electrophilic reagents led only to dimeric bis-uracil products, whereas the radical trifluoromethylation by CF 3SO2Na in presence of t-BuOOH gave 1,3-dimethyl-5- (trifluoromethyl)uracil (2) in good yield. The 6-(trifluoromethyl)uracil derivative 3 was only prepared in low yield and in a mixture with 2 by Ir-catalyzed borylation followed by treatment with the Togni's reagent. Attempted Pd-catalyzed C-H arylations of 2 in the presence of Cs 2CO3 gave mixtures of de-trifluoromethylated products, whereas the reaction with 4-iodotoluene in the presence of CsF gave the desired 6-aryl-5-trifluoromethyluracil derivative 8 in moderate yield and the reaction was not general for other aryl halides.

Exploration of photochemical reactions of N-trimethylsilylmethyl- substituted uracil, pyridone, and pyrrolidone derivatives

Photochemical reactions of N-trimethylsilylmethyl-substituted uracil, pyridone and pyrrolidone derivatives were carried out to determine if silicone containing substituents have an impact on excited state reaction profiles. The results show that ultraviolet irradiation of N-trimethylsilylmethyl substituted uracils in the presence of substituted alkenes leads to efficient formation of both dimeric and cross [2+2]-cycloaddition products. Qualitatively similar observations were made in a study of the photochemistry of N- trimethylsilylmethyl-2-pyridone. The combined results demonstrate that [2+2]-photocycloaddition is a more efficient excited state reaction pathway for the uracil and pyridone substrates as compared to other processes, such as ylide-forming trimethylsilyl group C-to-O migration. Finally, photoreactions of N-trimethylsilylmethyl-2-pyrrolidone in solutions containing dipolarophiles, such as methyl acrylate, lead to the formation of the desilylation product, N-methyl-2-pyrrolidone by way of a simple, non-ylide generating, protodesilylation process. In addition, observations were made which show that orbital symmetry allowed photocycloreversion reactions of dimeric uracil derivatives, involving cyclobutane ring splitting, to take place. These processes, which lead to the formation of monomeric uracils, appear to be stimulated by the presence of electron donor groups on the cyclobutane ring, a likely result of a new SET promoted cyclobutane ring cleavage pathway. In the cases of N-trimethylsilylmethyl-substituted cyclobutane derivatives that possess phthalimide groups, highly efficient excited state cleavage of the cyclobutane moiety occurs to produce uracil derivatives and corresponding vinyl phthalimide. The Royal Society of Chemistry and Owner Societies 2011.

PROCESS FOR STRAIGHTENING KERATIN FIBRES WITH A HEATING MEANS AND DENATURING AGENTS

The invention relates to a process for straightening keratin fibres, comprising: (i) a step in which a straightening composition containing at least two denaturing agents is applied to the keratin fibres, (ii) a step in which the temperature of the keratin fibres is raised, using a heating means, to a temperature of between 110 and 250° C.

The arylimines of 2,4-dioxo-1,2,3,4-tetrahydropyrimidine-5-carbaldehyde: Synthesis and their application in 1,3-dipolar cycloaddition reaction

(Chemical Equation Presented) A number of aldimines have been obtained in very good yield in reaction of 5-formyl-1,3-dimethyluracil with various substituted anilines in boiling methanol. Selected aldimines were treated with nitrile oxides generated from 4-chlorobenzaldoxime or 4-methylbenzaldoxime forming the appropriate 1,3-cycloadducts in moderate yields.