Lithiation-Trapping of saturated Oxygen and Sulfur Heterocycles

Substituted oxygen and sulfur heterocycles form the core of a number of drug molecules and natural products. In this thesis, the α-functionalisation of saturated oxygen and sulfur heterocycles, via direct lithiation and via Sn-Li exchange reactions from organostannanes, using organolithium reagents is described

α-Functionalisation of Cyclic Sulfides Enabled by Lithiation Trapping

A general and straightforward procedure for the lithiation / trapping of cyclic sulfides such as tetrahydrothiophene, tetrahydrothiopyran and a thiomorpholine is described. Trapping with a wide range of electrophiles is demonstrated, leading to more than 50 diverse α-substituted saturated sulfur heterocycles. The methodology provides access to a range of α-substituted cyclic sulfides that are not easily synthesised by the currently available methods