Iridium-catalyzed hydroacylation reactions of C1-substituted oxabenzonorbornadienes with salicylaldehyde: an experimental and computational study

Abstract

An experimental and theoretical investigation on the iridium-catalyzed hydroacylation of C1-substituted oxabenzonorbornadienes with salicylaldehyde is reported. Utilizing commercially available [Ir(COD)Cl]2 in the presence of 5 M KOH in dioxane at 65 °C, provided a variety of hydroacylated bicyclic adducts in up to a 95% yield with complete stereo- and regioselectivity. The mechanism and origins of selectivity in the iridium-catalyzed hydroacylation reaction has been examined at the M06/Def2TZVP level of theory. The catalytic cycle consists of three key steps including oxidative addition into the aldehyde C–H bond, insertion of the olefin into the iridium hydride, and C–C bond-forming reductive elimination. Computational results indicate the origin of regioselectivity is involved in the reductive elimination step.

Rh(i)-catalyzed site-selective hydroacylation of alkenyl-bearing allylic alcohols with non-chelating aldehydes controlled by in situ generated carbonyl group

“…According to the different types of coupling partners, there are two main categories: tethered unsaturated hydrocarbons and tethered aldehydes. The former involve the use of amide, 3 hydroxyl, 4 and sulfide groups, 5 and the latter encompass OH, 6 SR, 7 NR 2 , 8 PR 2 substituents, 9 and masked picolyl imines. 10 In 2021, Willis and co-workers reported an appealing example of using azine aldehyde N -oxides in intermolecular hydroacylation, and the single ‘O’ atom of the remaining N -oxide moiety could be readily removed under mild conditions.…”