Bis-ortho-metalation/silylation of unprotected o-phthalic acids. Straightforward access to new silylated N-hydroxyphthalimide (NHPI) analogs

The one pot, in situ ortho-metalation/silylation of unprotected o-phthalic acids using lithium tetramethylpiperidide (LiTMP) and chlorotrimethylsilane is described. This method gives a straightforward access to silylated phthalic anhydrides. These can be easily converted into the corresponding silylated N-hydroxyphthalimide (NHPI) analogs, which are promising new aerobic oxidation catalysts. (C) 2011 Elsevier Ltd. All rights reserved.