C. Perez, Y. L. Janin, D. R. Adams, C. Monneret<img border="0" src="https://www.rsc.org/images/entities/char_200a.gif" alt=" " xmlns="http://www.rsc.org/schema/rscart38" /> and D. S. Grierson, J. Chem. Soc., Perkin Trans. 1, 1997, 901 DOI: 10.1039/A605995C