Chlorodideuteriomethyl-lithium: a useful reagent for gem-dideuterated organic compounds

The reaction of ketones (6), at -780C, with in situ generated chlorodideuteriomethyl-lithium followed by lithiation leads to the dianionic intermediate (7) which yields dideuterio-alkenes (8) by warming or reacts with electrophiles such as dimethyl disulphide affording the compound (9); the same reaction sequence starting from benzoyl chloride leads to the cyclopropanol (12); when the intermediate in this last process (11) was warmed in absence or presence of lithium iodide the expected products (13) or (14) are respectively isolated. (author)