52334-07-3

Upstream product

• 23827-33-0 3-benzoylamino-1H-pyridin-2-one 
• 91813-32-0 N-(2-chloro-3-pyridinyl)phenylamide 
• 52200-48-3 3-bromo-2-chloropyridine 
• 55-21-0 benzamide 
• 39856-58-1 3-amino-2-bromopyridine 
• 135364-97-5 tert-butyl benzoyl(tert-butoxycarbonyl)carbamate 
• 7422-66-4 trimethylsilylphosphate 
• 127426-58-8 3-Cyclohexyl-4-hydroxymethyl-5-methyl-isoxazol 

Downstream Products

• 144782-77-4 2-Phenyl-oxazolo[5,4-b]pyridine-7-carbaldehyde 
• 144782-76-3 2-Phenyl-7-trimethylsilanyl-oxazolo[5,4-b]pyridine 
• 144782-75-2 1-(2-Phenyl-oxazolo[5,4-b]pyridin-7-yl)-cyclohexanol 
• 144782-72-9 Phenyl-(2-phenyl-oxazolo[5,4-b]pyridin-7-yl)-methanol 
• 144782-73-0 1-(2-Phenyl-oxazolo[5,4-b]pyridin-7-yl)-butan-1-ol 
• 144782-74-1 2-(2-Phenyl-oxazolo[5,4-b]pyridin-7-yl)-propan-2-ol 
• 136411-14-8 7-butyryl-2-phenyloxazolo<5,4-b>pyridine 
• 144782-79-6 7-benzoyl-2-phenyloxazolo<5,4-b>pyridine 

Relevant academic research and scientific papers

Cesium Fluoride and Copper-Catalyzed One-Pot Synthesis of Benzoxazoles via a Site-Selective Amide C?N Bond Cleavage

We report herein a two-step one-pot strategy for the synthesis of benzoxazoles from amides by using cesium fluoride/copper as catalysts. This approach involves the in situ generation of acyl fluorides from the corresponding amides, and the acyl fluorides undergo transamidation and cyclization to give benzoxazoles in good yields. In this work, the amide C?N bonds are activated by CsF to form the acyl fluoride intermediates, which further react with o-bromoanilines to efficiently yield benzoxazoles. Notably, this methodology demonstrates a broad substrate scope, as primary/secondary benzamides are well tolerated, and this process might facilitate the development of one-pot transformations of amides. (Figure presented.).

New palladium-catalyzed domino reaction with intramolecular ring closure of an N-(2-chloro-3-heteroaryl)arylamide: First synthesis of oxazolo[4,5-b] pyrazines

The synthesis of novel planar heterocycles is at the heart of basic research as such scaffolds constitute key building blocks in important diverse areas of research: drug discovery, material sciences, and pesticides. The well-known benzoxazole is often contained in drug candidates but tweaking its lipophilicity and target interaction points are often desired. In this respect, the oxazolo[4,5-b]pyrazine is an attractive heterocyclic scaffold as it possesses increased water solubility as well as two additional hydrogen bonding acceptors. We here report a new Pd(II)-catalyzed domino reaction comprising the first Pd(II)-assisted intramolecular cyclization of an N-(2-chloro-3-heteroaryl) arylamide and validate its value by application to the first synthesis of 2-substituted oxazolo[4,5-b]pyrazines. We demonstrate that a bidentate phosphorus ligand as well as the presence of an aromatic nitrogen atom is required for the domino reaction to proceed. The robustness of the methodology is confirmed by the synthesis of 23 2-substituted oxazolo[4,5-b]pyrazine analogues in good-to-high yields and containing both electron-withdrawing as well as electron-donating substituents on the reacting arylamide.

A general and efficient synthesis of 2-substituted oxazolopyridines

Starting from commercially available halonitropyridines and haloaminopyridines, 2-substituted-oxazolo[5,4-b]pyridines, and 2-aryl-oxazolo[4,5-b]pyridines were synthesized in good yields by using a Cu(I)-mediated cyclization of halopyridylamides as a key step. Georg Thieme Verlag Stuttgart.

A domino copper-catalyzed C-N and C-O cross-coupling for the conversion of primary amides into benzoxazoles

Benzoxazoles can be efficiently prepared in a single step and in good yield from primary amides and o-dihalobenzenes using Cu catalysis. Starting from substituted o-bromochlorobenzenes this unusual domino reaction allows the regioselective formation of benzoxazoles.

Process for the synthesis of oxazolopyridine compounds

Process for the synthesis of compounds of formula (I): STR1 their pyridinium salts and N-oxides, in which formula: the nitrogen of the pyridine ring is situated in the α-, β-, γ- or δ-position with respect to the ring junction; R1 represents a halogen, a substituted or unsubstituted alkyl, a substituted or unsubstituted alkoxy or a nitro, substituted or unsubstituted amino, phenyl or cyano group; 0≤m≤2; R2 represents a lower alkyl or cycloalkyl group, a 5- or 6-membered heterocycle containing 1 or 2 hetero atoms, substituted or otherwise, or an aryl group STR2 such that: R3 represents a halogen, a substituted or unsubstituted alkyl, a substituted or unsubstituted alkoxy or a nitro, phenyl, substituted or unsubstituted sulfonyl, cyano, thioalkyl, substituted or unsubstituted amino, substituted or unsubstituted sulfinyl, mercapto, hydroxyl or ester group, 0≤n≤5 employing trimethylsilyl polyphosphate (PPSE) as a cyclization agent and enabling the compounds of formula (I) to be obtained in virtually quantitative yields. The compounds of formula I have anti-inflammatory, analgesic, and antipyretic activity.

A New Convenient Synthesis of 2-Aryl- and 2-Heteroaryloxazolopyridines

Several 2-aryl- and 2-heteroaryloxazolopyridines were synthesized in high yields from 3-(arylcarbonylamino)-2-chloropyridines by heating in the presence of trimethylsilylpolyphosphate ester.

2-ARYL-OXAZOLO- AND THIAZOLOPYRIDINES. SYNTHESIS VIA CYCLIZATION OF N-(2-CHLORO-3-PYRIDINYL)ARYLAMIDES AND THIOAMIDES

Chloropyridinylenamides can by easily converted into oxazolo- and thiazolo pyridines by treatment with polyphosphoric acid and Lawesson reagent respectively.

Anti-inflammatory oxazole[4,5-b]pyridines

The various isomers of oxazolo- and thiazolopyridines having utility as antiinflammatory, antipyretic and analgesic agents are prepared by condensation of an appropriate amino-hydroxypyridine or amino-mercaptopyridine with a carboxylic acid, halide or anhydride.