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Abstract An unprecedented AgI‐catalyzed efficient method for the coupling of imino ethers and enol diazoacetates through a [3+2]‐cycloaddition/C−O bond cleavage/[1,5]‐proton transfer cascade process is reported. The general class of imino ethers that includes oxazolines, benzoxazoles and benzimidates are applicable substrates for these reactions that provide direct access to fully substituted pyrroles with uniformly high chemo‐ and regioselectivity. High variability in substitution at the pyrrole 2‐, 5‐ and N‐positions characterizes this methodology that also presents an entry point for further pyrrole diversification via facile modification of resulting N‐functional pyrroles.
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Base‐Promoted Synthesis of N−H Free Pyrroles via net [3+2]‐Cycloaddition
Abstract A base‐promoted net‐[3+2] cycloaddition of nitriles and 1‐arylpropynes for the synthesis of pyrroles is described. The developed method provides convenient access to various 2,5‐disubstituted or 2,4,5‐trisubstituted pyrroles in 40% to 96% yields (32 examples). Among methods for the synthesis of pyrroles, the protocol presented here stands out for its convenience and atom‐economy.
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- Award ID(s):
- 2154593
- PAR ID:
- 10493021
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Synthesis & Catalysis
- Volume:
- 366
- Issue:
- 4
- ISSN:
- 1615-4150
- Format(s):
- Medium: X Size: p. 942-947
- Size(s):
- p. 942-947
- Sponsoring Org:
- National Science Foundation
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