The rhodium(II)-catalyzed denitrogenative coupling of N-alkylsulfonyl 1,2,3-triazoles with 1,3,5-trioxane led to nine-membered-ringed trioxazonines in moderate-to-good yields. 1,3,5-Trioxane, acting as an oxygen nucleophile, reacted with the ?-aza-vinylcarbene intermediate, giving rise to ylide formation, which was probably the key step in the reaction. Triazoles that contained aryl substituents with various electronic and steric features on the C4 carbon atom were well-tolerated. The synthesis of trioxazonine derivatives was achieved through a one-pot, two-step procedure from 1-mesylazide and a terminal alkyne by combining Cu<sup>I</sup>-catalyzed 1,3-dipolar cycloaddition and rhodium-catalyzed transformations.
Rhodium(II)-Catalyzed Annulation of Azavinyl Carbenes Through Ring-Expansion of 1,3,5-Trioxane: Rapid Access to Nine-Membered 1,3,5,7-Trioxazonines
Ferraccioli R;
2015
Abstract
The rhodium(II)-catalyzed denitrogenative coupling of N-alkylsulfonyl 1,2,3-triazoles with 1,3,5-trioxane led to nine-membered-ringed trioxazonines in moderate-to-good yields. 1,3,5-Trioxane, acting as an oxygen nucleophile, reacted with the ?-aza-vinylcarbene intermediate, giving rise to ylide formation, which was probably the key step in the reaction. Triazoles that contained aryl substituents with various electronic and steric features on the C4 carbon atom were well-tolerated. The synthesis of trioxazonine derivatives was achieved through a one-pot, two-step procedure from 1-mesylazide and a terminal alkyne by combining CuI-catalyzed 1,3-dipolar cycloaddition and rhodium-catalyzed transformations.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
