Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2021 Jan 25;60(4):1897-1902.
doi: 10.1002/anie.202011602. Epub 2020 Nov 23.

A Dinickel Catalyzed Cyclopropanation without the Formation of a Metal Carbene Intermediate

Arnab K Maity  1 , Annah E Kalb  1 , Matthias Zeller  1 , Christopher Uyeda  1
Affiliations

A Dinickel Catalyzed Cyclopropanation without the Formation of a Metal Carbene Intermediate

Arnab K Maity et al. Angew Chem Int Ed Engl. .

Abstract

(NDI)Ni2 catalysts (NDI=naphthyridine-diimine) promote cyclopropanation reactions of 1,3-dienes using (Me3 Si)CHN2 . Mechanistic studies reveal that a metal carbene intermediate is not part of the catalytic cycle. The (NDI)Ni2 (CHSiMe3 ) complex was independently synthesized and found to be unreactive toward dienes. Based on DFT models, we propose an alternative mechanism that begins with a Ni2 -mediated coupling of (Me3 Si)CHN2 and the diene. N2 extrusion followed by radical C-C bond formation generates the cyclopropane product. This model reproduces the experimentally observed regioselectivity and diastereoselectivity of the reaction.

Keywords: carbenes; cyclopropane; homogeneous catalysis; metal-metal interactions; nickel.

PubMed Disclaimer

Conflict of interest statement

Conflict of interest

The authors declare no conflict of interest.

Figures

Figure 1.
Figure 1.
Metal carbenes are key intermediates in several catalytic cyclopropanation reactions using diazoalkanes. Dinickel complexes catalyze regioselective cyclopropanations of 1,3-dienes without generating a Ni2(μ-CR2) intermediate.
Figure 2.
Figure 2.
Ni2-catalyzed cyclopropanation of myrcene (2) using (Me3Si)CHN2 (3). Reaction conditions: 2 (0.05 mmol), 3 (0.06 mmol), catalyst (5 mol%), 22°C, 12 h, C6D6. Yields and trans/cis ratios were determined by 1H NMR integration.
Figure 3.
Figure 3.
Substrate scope studies. Reaction conditions: 1,3-diene (0.2 mmol), (Me3Si)CHN2 (0.22 mmol), 1 (5 mol%), 22°C, 6 h, C6H6. For 15, (PhMe2Si)CHN2 was used instead of (Me3Si)CHN2. Isolated yields and dr values were determined after purification by column chromatography.
Figure 4.
Figure 4.
A) Conversion of (i-PrNDI)Ni2(N2CHSiMe3) complex (18) into (i-PrNDI)Ni2(CHSiMe3) (19). B) Solid-state structure of 18. Selected bond lengths [Å] and angles [°]: Ni1-Ni2, 2.627(1); Ni1-N1 1.74(2); Ni2-N2 1.80(1); Ni2-N1 1.90(3); N1-N2 1.29(2); C1-N2, 1.30(1); C1-N2-N1 133(1). C) Solid-state structure of 19. Selected bond lengths [Å]: Ni1-Ni2 2.354(4); Ni1-C1 1.897(4); Ni2-C1 1.901(5). D) Solid-state structure of 20. Selected bond lengths [Å]: Ni1-Ni2 2.5778(5); Ni1-C1 1.970(2); Ni1-C2 2.062(2); Ni2-C3 1.982(2); Ni2-C4 1.992(2); C1-C2 1.384(4); C2-C3 1.456(3); C3-C4 1.368(4). For CCDC numbers, see the Supporting Information.
Figure 5.
Figure 5.
Stoichiometric cyclopropanation reactions with A) 18, B) 20, and C) 19. Yields and dr values were determined by 1H NMR integration.
Figure 6.
Figure 6.
Calculated reaction pathway for the (i-PrNDI)Ni2 catalyzed cyclopropanation to form 8 (BP86/6–311 g(d,p) level of DFT). Relative free energies are shown in kcalmol−1. Unless otherwise indicated, all structures correspond to S = 0 spin states. S7, S8, and S8′ were modelled as open-shell singlets with a C-centered α-TMS radical and the other unpaired electron delocalized in the NDI π-system. Transition states leading to the alternative regioisomer and diastereomer are shown.
See this image and copyright information in PMC

References

    1. Doyle MP, Chem. Rev. 1986, 86, 919–939;
    2. Lebel H, Marcoux J-F, Molinaro C, Charette AB, Chem. Rev. 2003, 103, 977–1050; - PubMed
    3. Davies HML, Manning JR, Nature 2008, 451, 417–424; - PMC - PubMed
    4. de Frémont P, Marion N, Nolan SP, Coord. Chem. Rev. 2009, 253, 862–892.
    1. Li Y, Huang J-S, Zhou Z-Y, Che C-M, You X-Z, J. Am. Chem. Soc. 2002, 124, 13185–13193; - PubMed
    2. Waterman R, Hillhouse GL, J. Am. Chem. Soc. 2003, 125, 13350–13351; - PubMed
    3. Dai X, Warren TH, J. Am. Chem. Soc. 2004, 126, 10085–10094; - PubMed
    4. Kornecki KP, Briones JF, Boyarskikh V, Fullilove F, Autschbach J, Schrote KE, Lancaster KM, Davies HML, Berry JF, Science 2013, 342, 351–354; - PubMed
    5. Marquard SL, Bezpalko MW, Foxman BM, Thomas CM, J. Am. Chem. Soc. 2013, 135, 6018–6021; - PubMed
    6. Werlé C, Goddard R, Philipps P, Farès C, Früstner A, J. Am. Chem. Soc. 2016, 138, 3797–3805. - PubMed
    1. Rittle J, Green MT, Science 2010, 330, 933–937. - PubMed
    1. Nam W, Ryu YO, Song WJ, J. Biol. Inorg. Chem. 2004, 9, 654–660; - PubMed
    2. Che C-M, Lo VK-Y, Zhou C-Y, Huang J-S, Chem. Soc. Rev. 2011, 40, 1950–1975; - PubMed
    3. Costas M, Coord. Chem. Rev. 2011, 255, 2912–2932.
    1. Collman JP, Chien AS, Eberspacher TA, Brauman JI, J. Am. Chem. Soc. 2000, 122, 11098–11100.

LinkOut - more resources