Abstract
The first chiral isoxazoline ligands bearing spiro skeleton are developed. The spiro bis(isoxazoline) ligands (SPRIXs) are readily synthesized from diethyl malonate via double intramolecular nitrile oxide cycloaddition as a key step. The complex of (M, S, S)-R-SPRIX and Pd(OCOCF3)2 promoted the catalytic asymmetric Wacker-type cyclization of alkenyl alcohols to give optically active cyclic ethers for the first time. Furthermore, starting from dialkenyl alcohol, the enantioselective tandem cyclization via oxy-palladation was achieved with up to 95% ee. Asymmetric ligands other than SPRIKs promote neither the Wacker-type reaction nor the tandem reaction.
Original language | English |
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Pages (from-to) | 59-69 |
Number of pages | 11 |
Journal | Yuki Gosei Kagaku Kyokaishi/Journal of Synthetic Organic Chemistry |
Volume | 62 |
Issue number | 1 |
DOIs | |
Publication status | Published - 2004 Jan |
Externally published | Yes |
Keywords
- Isoxazoline
- Nitrile oxide cycloaddition
- Palladium
- Spiro
- Tandem reaction
- Wacker-reaction
ASJC Scopus subject areas
- Organic Chemistry