Mannoside hexamers

To further expand the family of mannoside clusters obtainable from the alkyne derivatives, we also prepared cyclotrimerized hexamers using dicobalt octacarbonyl according to a known strategy (34). Thus dimer 37 and 30 were treated with Co2(CO)8 in refluxing dioxane to provide 48 and 50 in 61% and 42% yield, respectively (Scheme 9). 

---