5-(Methylthio)tetrazoles as Versatile Synthons in the Stereoselective Synthesis of Polycyclic Pyrazolines via Photoinduced Intramolecular Nitrile Imine-Alkene 1,3-Dipolar Cycloaddition.
Chem Sci
; 5(6): 2407-2415, 2014 Jun 01.
Article
en En
| MEDLINE
| ID: mdl-25114776
ABSTRACT
A key thioether substituent in readily accessible 2-alkyl-5-(methylthio)tetrazoles enables facile photoinduced denitrogenation and intramolecular nitrile imine 1,3-dipolar cycloaddition to afford a wide range of polycyclic pyrazoline products with excellent diastereoselectivity. The methylthio group red-shifts the UV absorbance of the tetrazole, obviating the requirement in all previous substrate systems for at least one aryl substituent, and can subsequently be converted into a variety of other functionalities. This synthetic platform has been applied to the concise total syntheses of the alkaloid natural products (±)-newbouldine and withasomnine.
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Colección:
01-internacional
Base de datos:
MEDLINE
Idioma:
En
Revista:
Chem Sci
Año:
2014
Tipo del documento:
Article
País de afiliación:
Estados Unidos