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Abstract BulkyN,N’‐bidentate ligands can furnish catalysts with enhanced catalytic activity compared to commercially available ligands. Straightforward methods to effectively synthesize a broad range of these ligands, however, are uncommon. In this work, a simple and efficient method is developed for the synthesis of bulkyN,N’‐bidentate ligands, including 2,2’‐bipyridines and enantioenriched pyridine‐oxazolines. The Pd/NIXANTPHOS catalyst system enabled synthesis of a series of bulky 2,2’‐bipyridine‐based ligands and (S)‐pyridine oxazoline‐based enantioenriched ligands with good to excellent yields. The ligands have been benchmarked in the aminofluorination of styrene. magnified image
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A Simple Procedure for the Synthesis of β ‐Hydroxyallenamides via Homoallenylation of Aldehydes
Abstract A simple one‐pot synthesis ofβ‐hydroxyallenamides is reported. This procedure entails chemo‐ and regioselective hydroboration of 3‐en‐1‐ynyl‐sulfonylamides with Cy2BH followed by homoallenylation of aldehydes to yield β‐hydroxyallenamides (up to 94% yield and >20:1 dr). Controlled synthesis of up to three continuous stereochemical elements was realized. Density functional theory (DFT) calculations suggest a concerted Zimmerman‐Traxler chair‐like transition state. Initial results suggest that enantio‐ and diastereoselective synthesis of β‐hydroxyallenamides with optically active hydroboration reagents is viable. magnified image
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- Award ID(s):
- 1464778
- PAR ID:
- 10053429
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Synthesis & Catalysis
- Volume:
- 360
- Issue:
- 7
- ISSN:
- 1615-4150
- Format(s):
- Medium: X Size: p. 1426-1432
- Size(s):
- p. 1426-1432
- Sponsoring Org:
- National Science Foundation
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