- Synthesis of bicyclic imidazoles via [2 + 3] cycloaddition between nitriles and regioselectively generated α-imino gold carbene intermediates.
Synthesis of bicyclic imidazoles via [2 + 3] cycloaddition between nitriles and regioselectively generated α-imino gold carbene intermediates.
Organic letters (2012-08-25)
Yuanjing Xiao, Liming Zhang
PMID22917160
ABSTRACT
The cyclic α-imino gold carbene intermediate B is most likely generated in situ via regioselective nitrene transfer from an azido group to a tethered terminal alkyne in the presence of a gold catalyst and at ambient temperature. This highly electrophilic intermediate can react with a weakly nucleophilic nitrile, which is used as the reaction solvent, to deliver a bicyclic imidazole rapidly in an overall bimolecular [2 + 2 + 1] cycloaddition and in mostly serviceable yield. The competing intramolecular Huisgen reaction, although likely also catalyzed by gold, is minimized by using AuCl(3) as the catalyst.
MATERIALS
Product Number
Brand
Product Description
SKU
Pack Size
Availability
Price
Quantity
SKU
Pack Size
Availability
Price
Quantity
SKU
Pack Size
Availability
Price
Quantity