“…Initially, we assumed that the ATRA reaction on either 13 or 15 would furnish a radical adduct bearing an iodine atom (see Scheme 1), which would have to be reduced, for example, with Bu 3 SnH. However, when we reacted carbamate 15 using the previously employed conditions (Et 3 B, O 2 , CH 2 Cl 2 , r.t.), 15 we observed a complex mixture of products where the only isolated product was not the expected ATRA adduct 16, but debenzylated carbamate 17 in 20% yield, along with a series of decomposition products (Table 1). Even though at this point we are not sure of the exact mechanism for this reductive ATRA reaction, a plausible mechanism might involve an intramolecular radical 1,5-hydrogen transfer, followed by oxidation of the resulting benzylic radical into an iminium salt and hydrolysis of the latter to produce the corresponding de- 19 17.…”