Acyclic 1,4-Stereocontrol via the Allylic Diazene Rearrangement: Development, Applications, and the Essential Role of Kinetic E Stereoselectivity in Tosylhydrazone Formation.
J Org Chem
; 82(16): 8359-8370, 2017 08 18.
Article
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| MEDLINE
| ID: mdl-28776373
ABSTRACT
We report full details of a method for 1,3-reductive transposition of α-alkoxy-α,ß-unsaturated hydrazones to provide E-alkenes with high 1,4-stereocontrol between the two respective allylic stereocenters. The process couples a chelation-controlled reduction of the hydrazone with an in situ allylic strain controlled retro-ene reaction of an allyl diazene, i.e., an allylic diazene rearrangement. Such stereotriads are frequently observed motifs in natural products. We observed a fortuitous kinetic preference for the E-hydrazone geometry during the hydrazonation reaction, as only the E-isomers could undergo chelation-controlled reduction.
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Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Compuestos de Tosilo
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Compuestos Alílicos
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Hidrazonas
/
Imidas
Idioma:
En
Revista:
J Org Chem
Año:
2017
Tipo del documento:
Article
País de afiliación:
Estados Unidos