Assembly strategy for thieno[3,2-b]thiophenes via a disulfide intermediate derived from 3-nitrothiophene-2,5-dicarboxylate

• Roman A. Irgashev

Beilstein J. Org. Chem. 2025, 21, 2489–2497, doi:10.3762/bjoc.21.191

• cyclization to furnish the TT framework [2][23][24]. Despite the wide structural diversity of TT derivatives, 3-hydroxy-substituted analogues remain rare, with only a few synthetic strategies described for their preparation, as illustrated in Scheme 1. One such route involves sulfur insertion into a thiophen

An efficient metal-free and catalyst-free C–S/C–O bond-formation strategy: synthesis of pyrazole-conjugated thioamides and amides

• Shubham Sharma,
• Dharmender Singh,
• Sunit Kumar,
• Vaishali,
• Rahul Jamra,
• Naveen Banyal,
• Deepika,
• Chandi C. Malakar and
• Virender Singh

Beilstein J. Org. Chem. 2023, 19, 231–244, doi:10.3762/bjoc.19.22

• ; pyrazole carbaldehydes; sulfur insertion; thioamides; Introduction During the past years, the significance of pyrazole chemistry has been notably escalated which is attributed to the discovery of their amazing biological properties. Among the heterocyclic molecules, pyrazoles are considered as privileged

• 10A in high yields (67–71%) within 1 hour of reaction time as depicted in Scheme 3. Thereafter, the substrates 4-iodopyrazole-3-carbaldehydes were further investigated for this metal- and catalyst-free sulfur insertion reaction as shown in Scheme 4. It was found that 4-iodopyrazole C-3 carbaldehydes

Et₃N/DMSO-supported one-pot synthesis of highly fluorescent β-carboline-linked benzothiophenones via sulfur insertion and estimation of the photophysical properties

• Dharmender Singh,
• Vipin Kumar and
• Virender Singh

Beilstein J. Org. Chem. 2020, 16, 1740–1753, doi:10.3762/bjoc.16.146

• excellent light-emitting properties with quantum yields (ΦF) up to 47%. Keywords: benzothiophene; β-carboline; metal-free; photophysical properties; sulfur insertion; Introduction The pyrido[3,4-b]indole moiety, commonly referred as β-carboline, is the core unit of about one quarter of all natural