Synthesis of 4-Membered Carbasugars by Way of Stereoselective SmI2-Mediated Aldehyde–Alkene Cyclization
摘要:
A stereodivergent synthesis of the first examples of 4-membered carbasugars has been achieved from vitamin C by way of an efficient intramolecular SmI2-mediated aldehyde-alkene coupling. In this key step, cylobutanes with four contiguous asymmetric centers are generated with a high level of stereocontrol.
High level of regiocontrol has been achieved in the C–H amination of substrates with a high density of reactive C–H bonds, allowing the access to a new class of conformationally constrained iminosugars.