DFT Study on the Mechanism of Palladium(0)-Catalyzed Reaction of Aryl Iodides, Norbornene, and Di-tert-butyldiaziridinone

Abstract

The reaction mechanism of palladium(0)catalyzed reaction of aryl iodides, norbornene, and di-tertbutyldiaziridinone has been studied theoretically. Two reaction mechanisms were calculated. The reaction mechanism involving Cs 2 CO 3 combination first followed by alkene insertion is calculated to be preferred to the one in which alkene insertion occurs first followed by Cs 2 CO 3 combination. The calculations suggest that the reaction proceeds via C−I bond oxidative addition, CsI•CsCO 3 cluster anion formation, alkene insertion, C−H bond activation, N−N bond oxidative addition, and two successive C(sp 2 )−N bond-forming, and C(sp 3 )−N bond-forming reductive elimination steps. The N− N bond oxidative addition involves the rate-determining transition state with a free energy barrier of 29.4 kcal/mol. The role of base Cs 2 CO 3 played during CsI•CsCO 3 cluster anion formation and N−N bond oxidative addition process has been discussed according to the formation of relatively strong Pd−O bond. The role of base K 2 CO 3 has been calculated and compared with Cs 2 CO 3 .

Reactivity and Selectivity Controlling Factors in the Pd/Dialkylbiarylphosphine-Catalyzed C–C Cleavage/Cross-Coupling of an N-Fused Bicyclo α-Hydroxy-β-Lactam

“…Intriguingly, the calculated intrinsic reaction coordinate (IRC) from TS-1oa leads to adduct 3 , where the Br atom resides on one of the cesium atoms. Thus, this oxidative addition process is an example of a “ base-mediated oxidative addition ,” as previously described by Musaev and co-workers as well as Liu and co-workers . Notably, H 1 , which was located within hydrogen bond distance of O 3 in prereaction complex 2 , transfers to the carbonate in TS-1oa .…”

Palladium-catalyzed C–H glycosylation and retro Diels–Alder tandem reaction via structurally modified norbornadienes (smNBDs)

“…Then, oxidative addition takes place through the transition state of C-ts to form intermediate D with a barrier of 14.8 kcal mol −1 from A to C-ts . Cs 2 CO 3 attacks the Pd center generating complex E , as suggested in Liu's work, 75 releasing around 56.8 kcal mol −1 . The C C of N8 coordinates with Pd forming four isomers F1 , F2 , F3 and F4 , as shown in Fig.…”

Mechanistic Insights into Formation of All-Carbon Quaternary Centers via Scandium-Catalyzed C–H Alkylation of Imidazoles with 1,1-Disubstituted Alkenes

“…All calculations were performed with Gaussian 09 . The functional M06-L, suitable for applications in transition metal chemistry, has been successfully used in numerous studies on transition metal-catalyzed organic reactions. − It was combined with the dispersion correction D3 in this work to enhance computational accuracy. Structures were optimized and characterized by frequency calculations to be energy minima (zero imaginary frequencies) or transition states (only one imaginary frequency) at the M06-L-D3/6-31G­(d,p) level with the solvent (toluene) effects included using the SMD solvation model.…”