141305-45-5

Basic information

• Product Name: Thiazole, 4,5-dimethyl-, 3-oxide
• Synonyms: Thiazole, 4,5-dimethyl-, 3-oxide
• CAS NO: 141305-45-5
• Molecular Formula: C₅H₇NOS
• Molecular Weight: 129.18
• Mol File: 141305-45-5.mol

Chemical Properties

• Appearance: /
• CAS DataBase Reference: Thiazole, 4,5-dimethyl-, 3-oxide(CAS DataBase Reference)
• NIST Chemistry Reference: Thiazole, 4,5-dimethyl-, 3-oxide(141305-45-5)
• EPA Substance Registry System: Thiazole, 4,5-dimethyl-, 3-oxide(141305-45-5)

Safety Data

• Hazardous Substances Data: 141305-45-5(Hazardous Substances Data)

Upstream product

• 3581-91-7 4,5-Dimethylthiazole 

Downstream Products

• 1127562-56-4 C₁₃H₁₅NOS 

Relevant articles and documents

Dehydration Polymerization for Poly(hetero)arene Conjugated Polymers

The lack of scalable and sustainable methods to prepare conjugated polymers belies their importance in many enabling technologies. Accessing high-performance poly(hetero)arene conjugated polymers by dehydration has remained an unsolved problem in syntheti

Hydroheteroarylation of Unactivated Alkenes Using N-Methoxyheteroarenium Salts

We report the first reductive coupling of unactivated alkenes with N-methoxy pyridazinium, imidazolium, quinolinium, and isoquinolinium salts under hydrogen atom transfer (HAT) conditions, and an expanded scope for the coupling of alkenes with N-methoxy pyridinium salts. N-Methoxy pyridazinium, imidazolium, quinolinium, and isoquinolinium salts are accessible in 1-2 steps from the commercial arenes or arene N-oxides (25-99%). N-Methoxy imidazolium salts are accessible in three steps from commercial amines (50-85%). In total 36 discrete methoxyheteroarenium salts bearing electron-donating, electron-withdrawing, alkyl, aryl, halogen, and haloalkyl substituents were prepared (several in multigram quantities) and coupled with 38 different alkenes. The transformations proceed under neutral conditions at ambient temperature, provide monoalkylation products exclusively, and form a single alkene addition regioisomer. Preparatively useful and complementary site selectivities in the addition of secondary and tertiary radicals to pyidinium salts are documented: harder secondary radicals favor C-2 addition (2->10:1), while softer tertiary radicals favor bond formation to C-4 (4.7->29:1). A diene possessing a 1,2-disubstituted and 2,2-disubstituted alkene undergoes hydropyridylation at the latter exclusively (61%) suggesting useful site selectivities can be obtained in polyene substrates. The methoxypyridinium salts can also be employed in dehydrogenative arylation, borono-Minisci, and tandem arylation processes. Mechanistic studies support the involvement of a radical process.

Palladium-catalyzed highly regioselective oxidative homocoupling of 1,2,3-triazole N-oxides

A convenient and highly regioselective palladium-catalyzed direct C–H homocoupling of 1,2,3-triazole N-oxides was developed in the presence of silver carbonate and 1,10-phenanthroline. This protocol provides a straightforward and operationally simple rout

Copper-catalyzed direct amination of 1,2,3-triazole N-oxides by C-H activation and C-N coupling

An efficient approach for the synthesis of 4-amino-2-aryl- 1,2,3-triazole derivatives has been developed through the copper-catalyzed direct C-H amination of 2-aryl-1,2,3-triazole N-oxides under mild reaction conditions. Various amines, including primary and secondary aliphatic and aromatic amines, can be employed as effective coupling partners. The general performance of our method was also demonstrated by the oxidative amination of thiazole and imidazole N-oxides.

A general synthesis of bis(o-azaheteroaryl)methane derivatives from N-oxides of azines and azoles

A general method of preparation of derivatives of bis(o-azaheteroaryl)methanes from aromatic N-oxides is reported, the key step of which is a 1,3-dipolar cycloaddition between N-oxides of azines or azoles and in situ generated terminal difluoroalkenes containing an o-azaheteroaryl substituent at the double bond. Selected products were applied for the preparation of two novel unsymmetrical analogues of BODIPY fluorescent dyes, containing both an imidazole and a quinoline or isoquinoline unit.

C2, C5, and C4 azole N-oxide direct arylation including room-temperature reactions

The N-oxide group imparts a dramatic increase in reactivity at all positions of the azole ring of thiazoles and imidazoles and changes the weak bias for C5 > C2 arylation to a reliable C2 > C5 > C4 reactivity profile. Use of this cross-coupling strategy enables high yielding and room-temperature C2 arylations, mild reactions at C5, and the first examples of C4 arylation-providing a unique opportunity for exhaustive functionalization of the azole core with complete control of regioselectivity. A correlation of reactivity with the relative contributions of each carbon atom to the HOMO is observed and discussed. Copyright

Easy access to the family of thiazole N-oxides using HOF·CH 3CN

An efficient procedure for transferring an oxygen atom to thiazole-containing compounds, resulting in the corresponding N-oxides, was developed by using HOF·CH3CN; mild reaction conditions, high yields and easy purification are the main features of this novel route, while X-ray structural analysis reveals a hydrogen bond between the N-oxide functionality and a water molecule. The Royal Society of Chemistry 2006.

Discovery of functionally selective 7,8,9,10-tetrahydro-7,10-ethano-1,2,4- triazolo[3,4-a]phthalazines as GABAA receptor agonists at the α3 subunit

We have previously identified the 7,8,9,10-tetrahydro-7,10-ethano-1,2,4- triazolo[3,4-a]phthalazine (1) as a potent partial agonist for the 0.3 receptor subtype with 5-fold selectivity in binding affinity over α1. This paper describes a detailed investigation of the substituents on this core structure at both the 3- and 6-positions. Despite evaluating a wide range of groups, the maximum selectivity that could be achieved in terms of affinity for the α3 subtype over the α1 subtype was 12-fold (for 57). Although most analogues showed no selectivity in terms of efficacy, some did show partial agonism at α1 and antagonism at α3 (e.g., 25 and 75). However, two analogues tested (93 and 96), both with triazole substituents in the 6-position, showed significantly higher efficacy for the α3 subtype over the α1 subtype. This was the first indication that selectivity in efficacy in the required direction could be achieved in this series.

New Methods for the Introduction of Substituents into Thiazoles

New methods for the regioselective introduction of substituents into thiazoles have been developed using thiazole, 2-phenylthiazole and 4,5-dimethylthiazole as representative thiazoles.Improved halogenation methods, displacement of hydroxy groups in combination with dehalogenation at C-5 yield all eight possible 2-phenyl-4-halo-, 5-halo and 4,5-dihalo-thiazoles in which halogen is chlorine and bromine.Peracid oxidation of the thiazoles gives the corresponding thiazole 3-oxides.These are not activated towards halogenation but are deprotonated with sodium hydride.The anion formed react with electrophiles such as paraformaldehyde, 2,2-dimethylpropanal, 2,2-dimethylpropanoyl chloride, hexachloroethane, tetrabromomethane, and dimethyl disulfide leading to the introduction of carbon substituents, halogen, and methylthio groups.In these reactions, the reactivity of the thiazole ring positions decreases in the order 2 than 5 than 4.Monoselectivity is low when halogen and methylthio groups are introduced since these substituents enhance the acidity of adjacent ring protons. 2-Phenyl-4,5-dihalothiazole 3-oxides lose the 5-halogen when treated with sulfite ion.Trimethyloxonium tetrafluoroborate O-methylates thiazole 3-oxides.Thiazole N-oxides also react with acetyl chloride and phosphorus oxychloride to afford chlorothiazoles in a non-selective manner.Phosphorus trichloride deoxygenates thiazole 3-oxides.