The asymmetric ene reaction of N-glyoxyloyl-(2R)-bornane-10,2-sultam with 1-pentene and 1-hexene
✍ Scribed by Artur Jeżewski; Katarzyna Chajewska; Zbigniew Wielogórski; Janusz Jurczak
- Publisher
- Elsevier Science
- Year
- 1997
- Tongue
- English
- Weight
- 508 KB
- Volume
- 8
- Category
- Article
- ISSN
- 0957-4166
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✦ Synopsis
The asymmetric ene reaction of N-glyoxyloyl-(2R)-bomane-10,2-sultam 2 and its hemiacetal 3 with 1-pentene 4 and 1-hexene 5 in the presence of Lewis acids is reported. All the ene reactions studied led to diastereoisomeric mixtures of olefins 6 and 7 or 8 and 9, with predominance of products of the (S) absolute configuration on the newly formed stereogenic center. The absolute configuration (via X-ray analysis of 6 and chemical correlation) and the extent of asymmetric induction were established. Stereochemical models are proposed. (~) 1997 Elsevier Science Ltd
📜 SIMILAR VOLUMES
## ~ -~~~ Starting from sultam 1, the chiral dienophile (2R)-N-glyoxyloylbornane-lO,2-sultam (4) was readily prepared. Non-catalyzed atmospheric-and high-pressure as well as [Eu(fod),]-promoted [4 + 21 cycloadditions of l-methoxybuta-l,3-diene (5) to chiral dienophile 4, leading with high asymmetr
The influence of Lewis acid on the diastereoselectivity of [4+2] cycloaddition of buta-1,3-diene to N-glyoxyloyl-(2R)bornane-10,2-sultam was investigated and high levels of asymmetric induction were achieved. (S)-3-[2-{(Methylsulfonyl)oxy}ethoxy]-4-(triphenylmethoxy)-1-butanol methanesulfonate were