Fluorinated phosphoric acid as a versatile effective catalyst for synthesis of series of benzimidazoles, benzoxazoles and benzothiazoles at room temperature

Mathapati, Sushil R.; Patil, Komal; Mathakari, Sujit S.; Suryawanshi, A. W.

doi:10.1080/10426507.2020.1871345

Cited by 19 publications

(8 citation statements)

References 47 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The description of experimental procedures, analytical and the spectra data of the ( 1 H NMR, 13 C NMR, 19 F NMR, elemental analysis) of synthesized compounds can be found in the Supplementary Information Section.…”

Section: Discussionmentioning

confidence: 99%

Switchable Synthesis of Benzothiazoles, Benzothiazines and Benzothiazepines through the Reaction of Hetareno[e]pyrrole‐2,3‐Diones with o‐Aminothiophenol

Belozerova,

Sukhanova,

Dmitriev

et al. 2024

ChemistrySelect

View full text Add to dashboard Cite

We report the substrate and conditions switchable synthetic methods for the preparation of benzothiazoles, benzothiazines and benzothiazepines based on the reactions of o‐aminothiophenol with hetareno[e]pyrrole‐2,3‐diones, 1H‐pyrrole‐2,3‐diones fused at the [e]‐side to heterocycles. The series of novel five‐, six‐ and seven‐membered N,S‐heterocycles were prepared in fair to excellent yields. The reported reactions proceeded under mild, catalyst‐free conditions, and the products were isolated by simple workup procedures.

show abstract

Section: Discussionmentioning

confidence: 99%

Switchable Synthesis of Benzothiazoles, Benzothiazines and Benzothiazepines through the Reaction of Hetareno[e]pyrrole‐2,3‐Diones with o‐Aminothiophenol

Belozerova,

Sukhanova,

Dmitriev

et al. 2024

ChemistrySelect

View full text Add to dashboard Cite

show abstract

“…Mathapati et al 65 used fluorophosphoric acid as a highly effective acid catalyst for the synthesis of benzoxazole derivatives ( 3 ) by the reaction of 2-aminophenol ( 1 ) and aromatic/aliphatic aldehyde ( 2 ) in ethanol under stirring at room temperature for 2.4 h. The advantages of this protocol are the use of inexpensive and stable catalysts with shorter reaction time and ambient conditions (Scheme 7; method 2).…”

Section: Synthesis Of Benzoxazole Derivativesmentioning

confidence: 99%

Advances in the synthetic strategies of benzoxazoles using 2-aminophenol as a precursor: an up-to-date review

Soni¹,

Sahiba²,

Teli³

et al. 2023

RSC Adv.

View full text Add to dashboard Cite

show abstract

“…2‐Ethylbenzo[d]thiazole (3w) [ 40 ] 1‐propanol (60.10 mg, 1 mmol) and 2‐aminothiophenol (125.19 mg, 1 mmol), yellow liquid (yield: 53% and 88 mg) 1 H NMR (400 MHz, CDCl 3 ) δ 7.78 (dd, J = 8.0, 4.6 Hz, 1H), 7.53 (t, J = 7.8 Hz, 1H), 7.17 (t, J = 7.7 Hz, 1H), 7.05 (q, J = 7.4 Hz, 1H), 3.12–2.56 (m, 2H), 1.20 (q, J = 8.0 Hz, 3H). 13 C{ 1 H} NMR (100 MHz, CDCl 3 ) δ 173.23, 153.20, 134.99, 125.76, 124.51, 122.40, 121.38, 27.60, 13.64.…”

Section: General Experimental Detailsmentioning

confidence: 99%

Synthesis and structural characterization of palladium pincer complexes: Sustainable synthesis of benzothiazoles

Anandaraj

Saranya

Ramesh

2023

Applied Organom Chemis

View full text Add to dashboard Cite

An efficient Pd(II)N^N^S pincer type catalysts‐promoted sustainable construction of pharmaceutically important benzothiazole derivatives from primary alcohols and 2‐aminothiophenol via acceptorless dehydrogenative coupling (ADC) method has been described. The newly synthesized ligand L2 and the Pd(II) complexes in addition to L1 and L3 were characterized by analytical and Fourier transform infrared spectroscopy (FT‐IR), UV–visible (UV–vis), and nuclear magnetic resonance (NMR) spectral techniques. Further, the ORTEP views of the complexes 2 and 3 were established by a single crystal XRD study, which evidenced the coordination of the thiosemicarbazone ligands and disclose the square‐planar geometry around the Pd(II) ion. The present homogeneous catalytic system involves synthesizing a range of benzothiazoles via C−S and C−N bond formation with excellent yields up to 93%. The described methodology employs a sustainable, highly abundant, and inexpensive alcohol as starting material using 1 mol% catalyst loading, and water and hydrogen gas are the only by‐products. Furthermore, a plausible mechanism involving in situ aldehyde formation via dehydrogenation of primary alcohols has been proposed. A large‐scale synthesis of 2‐(4‐methoxyphenyl)benzo[d]thiazole illustrates the synthetic utility of the present catalytic protocol.

show abstract

Fluorinated phosphoric acid as a versatile effective catalyst for synthesis of series of benzimidazoles, benzoxazoles and benzothiazoles at room temperature

Cited by 19 publications

References 47 publications

Switchable Synthesis of Benzothiazoles, Benzothiazines and Benzothiazepines through the Reaction of Hetareno[e]pyrrole‐2,3‐Diones with o‐Aminothiophenol

Switchable Synthesis of Benzothiazoles, Benzothiazines and Benzothiazepines through the Reaction of Hetareno[e]pyrrole‐2,3‐Diones with o‐Aminothiophenol

Advances in the synthetic strategies of benzoxazoles using 2-aminophenol as a precursor: an up-to-date review

Synthesis and structural characterization of palladium pincer complexes: Sustainable synthesis of benzothiazoles

Contact Info

Product

Resources

About