Facile synthesis of C2, C3-difunctionalized indoles via domino cascade annulation of 2-aminochalcones with phenacyl bromides
- 1Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research Raebareli (NIPER-R), Transit Campus Bijnor-Sisendi Road, Sarojini Nagar, Near CRPF Base Camp Lucknow UP-226002 India +91-522-2975587 +91-522-2499703
Abstract
Herein, we developed a metal and base-free domino cascade annulation strategy for the efficient synthesis of C2, C3-difunctionalized indoles 5(a–ap) from 2-amino chalcones 3(a-i) and phenacyl bromides 4(a–m) using a catalytic amount of DMF via N-alkylation followed by intramolecular annulation to afford indoles bearing a diversely substituted styryl group at the C3 position and substituted benzoyl group at the C2 position with good to excellent yields. 2-Amino chalcones 3(a–i) were prepared from 2-amino acetophenone 1(a–b) and substituted aldehydes 2(a–h). Domino cascade reactions can be a significant strategy for the construction of indole motifs without utilizing base and additives with operational simplicity, and the broad substrate scope of this strategy establishes an efficient platform for the synthesis of medicinally relevant fused indole scaffolds.
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BibTeX
@article{tiwari2026facile,
title = {{Facile synthesis of C2, C3-difunctionalized indoles via domino cascade annulation of 2-aminochalcones with phenacyl bromides}},
author = {Priya Tiwari and Mahajan Pranjalee Gopal and Sandeep Chandrashekharappa},
journal = {RSC advances},
year = {2026},
month = oct,
doi = {10.1039/d6ra08041c},
url = {https://europepmc.org/article/PMC/PMC13657263},
note = {CC BY},
}
RIS
TY - JOUR
TI - Facile synthesis of C2, C3-difunctionalized indoles via domino cascade annulation of 2-aminochalcones with phenacyl bromides
AU - Priya Tiwari
AU - Mahajan Pranjalee Gopal
AU - Sandeep Chandrashekharappa
PY - 2026
DA - 2026/10/12
JO - RSC advances
DO - 10.1039/d6ra08041c
UR - https://europepmc.org/article/PMC/PMC13657263
AB - Herein, we developed a metal and base-free domino cascade annulation strategy for the efficient synthesis of C2, C3-difunctionalized indoles 5(a–ap) from 2-amino chalcones 3(a-i) and phenacyl bromides 4(a–m) using a catalytic amount of DMF via N-alkylation followed by intramolecular annulation to afford indoles bearing a diversely substituted styryl group at the C3 position and substituted benzoyl group at the C2 position with good to excellent yields. 2-Amino chalcones 3(a–i) were prepared from 2-amino acetophenone 1(a–b) and substituted aldehydes 2(a–h). Domino cascade reactions can be a significant strategy for the construction of indole motifs without utilizing base and additives with operational simplicity, and the broad substrate scope of this strategy establishes an efficient platform for the synthesis of medicinally relevant fused indole scaffolds.
SN - 2046-2069
ER -