Diastereoselective synthesis of sparteine analogues via lithiation–electrophilic quench of N-Boc bispidines

Lithiation of a N-Boc bispidine and subsequent trapping with a range of electrophiles has been investigated as a new route to sparteine analogues. The reactions proceed with complete diastereoselectivity to generate products with the same relative stereochemistry as in the ABC rings of sparteine.