desymmetrization of cyclic anhydrides is carried out using dihydroxy compounds. A mild route to synthesize fused saturated/unsaturated macrocyclic tetralactones with different ring sizes (20-34) having a wide variety of spacers is described. The structure is confirmed by the representative single-crystal X-ray analysis. The multiple reduction of unsaturated macrocyclic tetralactones is also illustrated. This method
The ringclosingmetathesisreaction in the presence of Grubbs catalyst was demonstrated using several ionic liquids to synthesize a range of macrocyclic tetralactones having ring size of 19 to 31 membered with different spacers. The ionic liquid [mmim][PF6] was found to be an excellent solvent and the recovery of the catalyst was demonstrated. X-ray analysis of a representative macrocyclic tetralactone