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A new selenophosphoramide-catalyzed diamination of terminal- and trans -1,2-disubstituted olefins is presented. Key to the success of this transformation was the introduction of a fluoride scavenger, trimethylsilyl trifluoromethanesulfonate (TMSOTf), to prevent a competitive syn -elimination pathway, as was the use of a phosphoramide ligand on selenium to promote the desired substitution reaction. A screen of catalysts revealed that more electron-rich phosphine ligands resulted in higher yields of the desired product, with selenophosphoramides giving the optimal results. A broad range of substrates and functional groups were tolerated and yields were generally good to excellent. For ( E )-1,2-disubstituted olefins, diastereoselectivities were always high, giving exclusively anti products. The conditions were also applied to substrates bearing internal nucleophiles such as esters and carbonates, giving rise to 1,2-aminoesters and cyclic carbonates, respectively.
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This content will become publicly available on April 24, 2026
Synthesis of 2-Arylpyrroles via an Optimized Palladium Coupling
Abstract Using response surface methods, we have re-optimized a palladium-catalyzed method for coupling ClZn(pyrrolide) with aryl bromides to selectively generate 2-arylpyrroles. We optimized based on four variables: temperature, ClZn(pyrrolide)/ArBr ratio, catalyst loading, and time. To find a protocol applicable to most substrates of interest, we optimized three different substrates: a bulky arene (mesityl bromide), an electron-rich arene [4-(NMe2)C6H4Br], and an electron-deficient arene [3,5-(CF3)2C6H3Br]. The re-optimized procedures give as good or better yields than the previously published protocols, always in a fraction of the time. In addition, the reactions are generally cleaner with the new conditions, especially with electron-rich substrates, making the products easier to isolate. We applied the conditions to a variety of different substrates in each category, which provided good to excellent isolated yields.
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- Award ID(s):
- 2247064
- PAR ID:
- 10621622
- Publisher / Repository:
- Synthesis
- Date Published:
- Journal Name:
- Synthesis
- Volume:
- 57
- Issue:
- 10
- ISSN:
- 0039-7881
- Page Range / eLocation ID:
- 1733 to 1741
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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