The enantioselective palladium‐catalyzed decarboxylative allylic alkylation of fully substituted α‐hydroxy acyclic enol carbonates providing tetrasubstituted benzoin derivatives is reported. Investigation into the transformation revealed that preparation of the starting material as a single enolate isomer is crucial for optimal enantioselectivity. The obtained alkylation products contain multiple reactive sites that can be utilized toward the synthesis of stereochemically rich derivatives.
Alkylation of Indoles with α,β‐Unsaturated Ketones using Alumina in Hexanes
We evaluated the influence of solvent on the alumina‐promoted C3‐alkylation of indoles with α,β‐unsaturated ketones. We found that lipophilic solvents were generally superior to hydrophilic ones with hexanes offering the 3‐alkyl indole products in high yields. Thus, we demonstrate an inexpensive and procedurally simple new process that pairs acidic alumina with hexanes to achieve this important Michael alkylation. The substrate scope includes twenty‐four examples with reaction yields ranging from 61 to 96%.
- NSF-PAR ID:
- 10123977
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Synthesis & Catalysis
- Volume:
- 361
- Issue:
- 24
- ISSN:
- 1615-4150
- Page Range / eLocation ID:
- p. 5548-5551
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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