Functionalized spiro- and fused-ring heterocycles via oxidative demetalation of cyclohexadienyl ruthenium complexes.

@article{Pigge2004FunctionalizedSA,
  title={Functionalized spiro- and fused-ring heterocycles via oxidative demetalation of cyclohexadienyl ruthenium complexes.},
  author={F. Pigge and J. J. Coniglio and N. Rath},
  journal={The Journal of organic chemistry},
  year={2004},
  volume={69 4},
  pages={
          1161-8
        }
}
Electron-rich alkoxy- and chloro-substituted azaspirocyclic cyclohexadienyl Ru(II) complexes have been converted to either azaspiro[4.5]decane derivatives or functionalized tetrahydroisoquinolines by treatment with suitable oxidizing agents. Copper(II) chloride was found to provide demetalated products in high yield relative to the other oxidants examined (FeCl(3), DDQ, CAN, [Cp(2)Fe][PF(6)], phenyliodine diacetate, IBX). In certain instances, the efficiency of oxidative demetalation was… Expand
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