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, ...
[Bowman, W. Russell; Fletcher, Anthony J.; Pedersen, Jan M.; Lovell, Peter J.; Elsegood, Mark R.J.; Hernandez Lopez, Elena; McKee, Vickie; Potts, Graeme B.S. Tetrahedron, 2007 , vol. 63, # 1 p. 191 - 203]