Multicomponent domino reactions of hydrazinecarbodithioates: concise access to 3-substituted 5-thiol-1,3,4-thiadiazolines.
نویسندگان
چکیده
Two classes of addition/cycloaddition cascade reactions of hydrazinecarbodithioate (1) have been developed under mild reaction conditions. Reaction of hydrazinecarbodithioate (1) with formaldehyde solution (2) and propiolic acid (3) gives 3-propargyl-5-thiol-2,3-dihydro-1,3,4-thiadiazoles (5) via a decarboxylative coupling/cycloaddition domino sequence. When propiolic acid (3) is switched to phenyl boronic acid (4), a petasis/cycloaddition domino reaction is instead observed, in which 3-benzyl-5-thiol-2,3-dihydro-1,3,4-thiadiazoles (6) are obtained. Both these reactions show a wide range of functional-group compatibility for propiolic acids and aryl boronic acids, and give the corresponding products in moderate to good yields.
منابع مشابه
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ورودعنوان ژورنال:
- Organic & biomolecular chemistry
دوره 13 30 شماره
صفحات -
تاریخ انتشار 2015