has proven to be effective in the formation of syn product 3ae in excellent diastereoselectivity (01:99) and 72% yield (Figure ). It is important to emphasize, that all three constitutional products of anti-3, syn-3 and 8 were separated by column chromatography (Figure ). Their structure and the relative syn-and anti-configuration were determined by 2D-NMR NOESY studies (of 3z-af see Supporting Information for more details pages S254-S259).