Barton esters for initiator-free radical cyclisation with heteroaromatic substitution.
نویسندگان
چکیده
S-(1-Oxido-2-pyridinyl)-1,1,3,3-tetramethylthiouronium hexafluorophosphate (HOTT) facilitates the first examples of efficient radical cyclisation with (hetero)aromatic substitution via Barton ester intermediates. Cyclopropyl and alkyl radicals allow access to five, six and seven-membered alicyclic-ring fused heterocycles with and without an additional fused cyclopropane, including the skeleton of the anti-cancer agent, cyclopropamitosene, expanded, and diazole analogues. Radical initiators are not required for cyclisation from carboxylic acid precursors.
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ورودعنوان ژورنال:
- Organic & biomolecular chemistry
دوره 11 10 شماره
صفحات -
تاریخ انتشار 2013