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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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Preparation, Structure, and Reactivity of Pseudocyclic β‐Trifluorosulfonyloxy Vinylbenziodoxolone Derivatives
Abstract Pseudocyclic β‐trifluorosulfonyloxy vinylbenziodoxolones were prepared starting from hydroxybenziodoxolones and alkynes in the presence of trifluoromethanesulfonic acid. The reaction of these compounds with azide anion leads to β‐azido vinylbenziodoxolones as products of vinylic nucleophilic substitution in which addition‐elimination reactions occur and the double bond configuration is retained. The structures of β‐trifluorosulfonyloxy vinylbenziodoxolone and β‐azido vinylbenziodoxolone were established by single crystal X‐ray diffraction. magnified image
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- Award ID(s):
- 1759798
- PAR ID:
- 10232009
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Synthesis & Catalysis
- Volume:
- 363
- Issue:
- 13
- ISSN:
- 1615-4150
- Format(s):
- Medium: X Size: p. 3365-3371
- Size(s):
- p. 3365-3371
- Sponsoring Org:
- National Science Foundation
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