Jump to main content
Jump to site search

Issue 40, 2019
Previous Article Next Article

Mechanism and origins of ligand-controlled Pd(ii)-catalyzed regiodivergent carbonylation of alkynes

Author affiliations

Abstract

Transition-metal-catalyzed carbonylation provides a useful approach to synthesize carbonyl-containing compounds and their derivatives. Controlling the regio-, chemo-, and stereoselectivity remains a significant challenge and is the key to the success of transformation. In the present study, we explored the mechanism and origins of the ligand-controlled regiodivergent carbonylation of alkynes with competitive nucleophilic amino and hydroxy groups by density functional theory (DFT) calculations. The proposed mechanism involves O(N)-cyclization, CO insertion, N–H(O–H) cleavage, C–N(C–O) reductive elimination and regeneration of the catalyst. The chemoselectivity is determined by cyclization. Instead of the originally proposed switch of competitive coordination sites, a new type of concerted deprotonation/cyclization model was proposed to rationalize the ligand-tuned chemoselectivity. The electron-deficient nitrogen-containing ligand promotes the flow of electrons during cyclization, and so it favors the O-cyclization/N-carbonylation pathway. However, sterically bulky and electron-rich phosphine controls the selectivity by a combination of electronic and steric effects. The improved mechanistic understanding will enable further design of selective transition-metal-catalyzed carbonylation.

Graphical abstract: Mechanism and origins of ligand-controlled Pd(ii)-catalyzed regiodivergent carbonylation of alkynes

Back to tab navigation

Supplementary files

Publication details

The article was received on 13 Aug 2019, accepted on 03 Sep 2019 and first published on 04 Sep 2019


Article type: Paper
DOI: 10.1039/C9DT03294K
Dalton Trans., 2019,48, 15059-15067

  •   Request permissions

    Mechanism and origins of ligand-controlled Pd(II)-catalyzed regiodivergent carbonylation of alkynes

    J. Liu, X. Zhang, Y. Tian, X. Wang, X. Zhu and D. Chen, Dalton Trans., 2019, 48, 15059
    DOI: 10.1039/C9DT03294K

Search articles by author

Spotlight

Advertisements