Dithioketals alkali metals

Use of excess alkali metal in liquid ammonia or an amine (generally EtNH2 or ethylenediamine, EDA) is also a widespread procedure used to desulfurize sulEdes, dithioketals and sulfones. - - From the numerous works published, a number of interesting features emerge. Thus desulfurization of sulfides in liquid NH3-THF tolerates esters and ketones, while Li-EtNH2 cleaves the C—S bonds of unsaturated substrates without side reactions (Scheme 1). Sodium in liquid ammonia was found to be a better... 

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