Asymmetric Diels-Alder reactions of 1,3-disiloxycyclohexadiene with chiral acrylamides
✍ Scribed by Hélène Lamy-Schelkens; Léon Ghosez
- Publisher
- Elsevier Science
- Year
- 1989
- Tongue
- French
- Weight
- 250 KB
- Volume
- 30
- Category
- Article
- ISSN
- 0040-4039
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✦ Synopsis
Diets-Alder reactions of 1,3-disiloxycyclohexadiene 2 with acrylamide a, derived from a chiral pyrrolidine possessing C2 symmetry, occur with high endo : exo and diastereofacial selectivities.
The endo : exo ratio is controlled by the choice of the catalyst.
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R2AlC~-ordinate ~-meth~~loy~ul~ lc undergoes efficient, t&o-selective and highly diastereofact controlled [4+2]-additions to cyclopentadiene, isoprene, fE)-piperylene and the 2-silyloxydieaes 10 and 12. The resulting crystalline cyclogdducts are smoothly reduced with LiAlH4 providing the recovered a
Excellent diastereofacial discriminations have been observed for the addition of 1,4\_naphthoquinone to alkoxycyclohexa-1,3-dienes subject to appropriate selection of a chiral alkoxy group.
## Abstract For Abstract see ChemInform Abstract in Full Text.
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