A One-Pot Reaction of α-Imino Rhodium Carbenoids and Halohydrins: Access to 2,6-Substituted Dihydro-2<i>H</i>-1,4-oxazines
Kieran D. Jones, Michael J. Nutt, Elena Comninos, Alexandre N. Sobolev, Stephen A. Moggach, Tomoya Miura, Masahiro Murakami, Scott G. Stewart
Abstract
Herein, we report a Rh(II)-catalyzed reaction between 1-tosyl-1,2,3-triazoles and halohydrins to provide 2,6-substituted 3,4-dihydro-2H-1,4-oxazines under basic conditions. The reaction is proposed to undergo a rhodium carbenoid 1,3-insertion into O–H followed by an annulation. The scope includes phenyl or alkenyl C4-substituted triazoles and a range of halohydrins using catalytic Rh2Oct4 and K2CO3. A synthesis of the antimicrobial natural product (±)-chelonin C is also reported using this novel methodology.
Topics & Concepts
ChemistryRhodiumOxazinesMedicinal chemistryCombinatorial chemistryOrganic chemistryCatalysisCyclopropane Reaction MechanismsCatalytic C–H Functionalization MethodsCatalytic Alkyne Reactions