文摘
Under the cooperative catalysis of NHC/Lewis acid, the mild, straightforward [4 + 2] annulation of 伪-bromo-伪,尾-unsaturated aldehydes bearing 纬-H with isatin derivatives gave spirocyclic oxindole鈥揹ihydropyranones stereoselectively. This approach is particularly attractive due to the concise construction, avoidance of external oxidants, and the potential utilization value of final products in molecular biology and pharmacy.