Diiodides ethers, cyclic

The two substituents on the /3-lactam can be longer and either saturated or unsaturated alkyl groups. The bromo alcohol 259 undergoes cyclization in the presence of base (triethylamine was found to give the best result) to yield the cyclic ether 260 <2005PAC2061>. The unsaturated diiodide 261 yields 262 upon reaction with sodium sulfide <1995TL7913>. 

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