123166-18-7Relevant articles and documents
Umpolung Strategy for Arene C?H Etherification Leading to Functionalized Chromanes Enabled by I(III) N-Ligated Hypervalent Iodine Reagents
Mikhael, Myriam,Guo, Wentao,Tantillo, Dean J.,Wengryniuk, Sarah E.
supporting information, p. 4867 - 4875 (2021/09/14)
The direct formation of aryl C?O bonds via the intramolecular dehydrogenative coupling of a C?H bond and a pendant alcohol represents a powerful synthetic transformation. Herein, we report a method for intramolecular arene C?H etherification via an umpoled alcohol cyclization mediated by an I(III) N-HVI reagent. This approach provides access to functionalized chromane scaffolds from primary, secondary and tertiary alcohols via a cascade cyclization-iodonium salt formation, the latter providing a versatile functional handle for downstream derivatization. Computational studies support initial formation of an umpoled O-intermediate via I(III) ligand exchange, followed by competitive direct and spirocyclization/1,2-shift pathways. (Figure presented.).
Organolanthanide-Catalyzed Cyclization/Boration of 1,5- and 1,6-Dienes
Molander, Gary A.,Pfeiffer, Dirk
, p. 361 - 363 (2007/10/03)
(Matrix Presented) 1,5- and 1,6-Dienes undergo a cyclization/boration reaction in the presence of a catalytic amount of Cp*2Sm·THF. The resulting organoboranes can be oxidized to the corresponding primary cyclic alcohols using standard conditions.
Auxiliary-directed peroxidation of 1,4-dienes
Dussault, Patrick H.,Anderson, Todd A.,Hayden, Michael R.,Koeller, Kevin J.,Jason Niu
, p. 12381 - 12398 (2007/10/03)
The addition of singlet oxygen (1O2) to the proximal alkene of auxiliary-tethered 1,4-dienes and the addition of triplet oxygen 3O2) to the proximal position of the corresponding pentadienyl radicals both produce conjugated diene hydroperoxides in moderate to high diastereomeric excess. Negligible stereoselection is observed for additions of 1O2 to the distal alkene of Z,Z-heptadienes due to the lack of control of alkene conformation. Despite evidence for the intermediacy of highly constrained pentadienyl radicals, poor diastereoselection is also observed for distal addition of 3O2. The extent of olefin isomerization observed during radical oxygenations can be correlated with steric constraints on the intermediate pentadienyl and peroxyl radicals and may be relevant to literature reports of olefin isomerization during enzymatic oxygenations of unnatural fatty acids.
