Subject 1,2-ethanedithiol

The aminals remained intact when subjected to various other transformation conditions, including the BF3-l,2-ethanedithiol conditions. The parent imidazole aminals react with organo-lithium reagents similarly to the unprotected aldehyde hy first proton abstract of 2-H proton of imidazole and subsequent retro-[l,4]-Brook rearrangement. The 2-substituted imidazoles (e.g., 2-methylimidazole), on the contrary, generate aminals which are stable to organohthium reagents. ... 

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