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
. 2022 Feb 4;24(4):1005-1010.
doi: 10.1021/acs.orglett.1c03124. Epub 2022 Jan 26.

Contra-thermodynamic Olefin Isomerization by Chain-Walking Hydroboration and Dehydroboration

Steven Hanna  1 , Brandon Bloomer  1 , Nicodemo R Ciccia  1 , Trevor W Butcher  2 , Richard J Conk  1 , John F Hartwig  1
Affiliations

Contra-thermodynamic Olefin Isomerization by Chain-Walking Hydroboration and Dehydroboration

Steven Hanna et al. Org Lett. .

Abstract

We report a dehydroboration process that can be coupled with chain-walking hydroboration to create a one-pot, contra-thermodynamic, short- or long-range isomerization of internal olefins to terminal olefins. This dehydroboration occurs by a sequence comprising activation with a nucleophile, iodination, and base-promoted elimination. The isomerization proceeds at room temperature without the need for a fluoride base, and the substrate scope of this isomerization is expanded over those of previous isomerizations we have reported with silanes.

PubMed Disclaimer

Conflict of interest statement

Notes

The authors declare no competing financial interest.

Figures

Scheme 1.
Scheme 1.
Development of a Long-Range, Contra-thermodynamic Olefin Isomerization through Hydroboration and Dehydroboration
Scheme 2.
Scheme 2.. Contra-thermodynamic Olefin Isomerizations in the Presence of Catalyst C1
Step 1: Internal olefin (0.640 mmol), HBpin (1.05 equiv), C1 (2 mol %), rt, 24 h, MTBE (640 μL). Step 2: KOMe (3 equiv), I2 (3 equiv), KOtBu (1.5 equiv), portionwise, 3 iterations; KOtBu (5 equiv). aYield of terminal olefin determined 1H NMR spectroscopy with trichloroethylene as internal standard. bTerminal/internal ratio. cIsolated yield of terminal olefin. dWith 0.320 mmol of olefin, scaled accordingly. e5 mol % C1. f3 mol % C1. gStep 1 conducted over 72 h. hHydroboration, iodination, and elimination steps conducted at 65 °C.
Scheme 3.
Scheme 3.. Contra-thermodynamic Olefin Isomerizations in the Presence of Catalyst C2
Step 1: Internal olefin (0.640 mmol), HBpin (1.05 equiv), C2 (3–7 mol %), rt, 24 h. Step 2: KOMe (3–4 equiv), I2 (3–4 equiv), KOtBu (1.5–2 equiv), portionwise, 3–4 iterations; KOtBu (5–6 equiv). aYield of terminal olefin determined by 1H NMR spectroscopy with trichloroethylene as internal standard. bTerminal/internal ratio. cIsolated yield of terminal olefin. dStep 1 conducted at 50 °C for 72 h. eStep 1 conducted at 50 °C for 168 h. fHydroboration reaction mixture filtered over silica prior to dehydroboration. gWith 0.320 mmol of internal olefin, reagents scaled accordingly.
See this image and copyright information in PMC

References

    1. Biswas S; Huang Z; Choliy Y; Wang DY; Brookhart M; Krogh-Jespersen K; Goldman AS Olefin Isomerization by Iridium Pincer Catalysts. Experimental Evidence for an η3-Allyl Pathway and an Unconventional Mechanism Predicted by DFT Calculations. J. Am. Chem. Soc. 2012, 134, 13276. - PubMed
    2. Larionov E; Li H; Mazet C Well-Defined Transition Metal Hydrides in Catalytic Isomerization. Chem. Commun. 2014, 50, 9816. - PubMed
    3. Crossley SWM; Barabé F; Shenvi RA Simple, Chemoselective, Catalytic Olefin Isomerization. J. Am. Chem. Soc. 2014, 136, 16788. - PMC - PubMed
    4. Molloy JJ; Morack T; Gilmour R Positional and Geometrical Isomerisation of Alkenes: The Pinnacle of Atom Economy. Angew. Chem., Int. Ed. 2019, 58, 13654. - PubMed
    5. Scaringi S; Mazet C Kinetically Controlled Stereoselective Access to Branched 1,3-Dienes by Ru-Catalyzed Remote Conjugative Isomerization. ACS Catal. 2021, 11, 7970.
    6. Fiorito D; Scaringi S; Mazet C Transition metal-catalyzed alkene isomerization as an enabling technology in tandem, sequential and domino processes. Chem. Soc. Rev. 2021, 50, 1391. - PubMed
    1. Harwood LM; Julia M A Convenient Synthesis of (+)-β-Pinene from (+)-α-Pinene. Synthesis 1980, 1980, 456.
    2. Min Y-F; Zhang B-W; Cao Y A New Synthesis of (−)-β-Pinene from (−)-α-Pinene. Synthesis 1982, 1982, 875.
    3. Andrianome M; Häberle K; Delmond B Allyl-and benzylstannanes, new reagents in terpenic synthesis. Tetrahedron 1989, 45, 1079.
    4. Eng SL; Ricard R; Wan CSK; Weedon AC Photochemical Deconjugation of α,β-Unsaturated Ketones. J. Chem. Soc., Chem. Commun. 1983, 236, 236.
    5. Guignard RF; Petit L; Zard SZ A Method for the Net Contra-thermodynamic Isomerization of Cyclic Trisubstituted Alkenes. Org. Lett. 2013, 15, 4178. - PubMed
    1. Brown H Isomerization of internal olefins to terminal olefins. US3173967A, 1965.
    2. Brown HC; Bhatt MV; Munekata T; Zweifel G Organoboranes. VII. The Displacement Reaction with Organoboranes Derived from the Hydroboration of Cyclic and Bicyclic Olefins. Conversion of Endocyclic to Exocyclic Double Bonds. J. Am. Chem. Soc. 1967, 89, 567.
    3. Brown HC; Bhatt MV Organoboranes. IV. The Displacement Reaction with Organoboranes Derived from the Hydroboration of Branched-Chain Olefins. A Contrathermodynamic Isomerization of Olefins. J. Am. Chem. Soc. 1966, 88, 1440.
    4. Robert H; Allen RWL; Andrew D Overstreet Continuous Process for Preparing Aluminm 1-Alkyls and Linear 1-Olefins from Internal Olefins. US005274153A 1993.
    5. de Klerk A; Hadebe SW; Govender JR; Jaganyi D; Mzinyati AB; Robinson RS; Xaba N Linear α-Olefins from Linear Internal Olefins by a Boron-Based Continuous Double-Bond Isomerization Process. Ind. Eng. Chem. Res. 2007, 46, 400.
    1. Hanna S; Wills T; Butcher TW; Hartwig JF Palladium-Catalyzed Oxidative Dehydrosilylation for Contra-Thermodynamic Olefin Isomerization. ACS Catal. 2020, 10, 8736.
    2. Hanna S; Butcher TW; Hartwig JF Contra-thermodynamic Olefin Isomerization by Chain-Walking Hydrofunctionalization and Formal Retro-hydrofunctionalization. Org. Lett. 2019, 21, 7129. - PubMed
    1. Yarosh OG; Zhilitskaya LV; Yarosh NK; Albanov AI; Voronkov MG Hydrosilylation of Cyclohexene, 1-Methylcyclohexene, and Isopropylidenecyclohexane. Russ. J. Gen. Chem. 2004, 74, 1895.
    2. Lata CJ; Crudden CM Dramatic Effect of Lewis Acids on the Rhodium-Catalyzed Hydroboration of Olefins. J. Am. Chem. Soc. 2010, 132, 131. - PubMed
    3. Obligacion JV; Chirik PJ Bis(imino)-pyridine Cobalt-Catalyzed Alkene Isomerization–Hydroboration: A Strategy for Remote Hydrofunctionalization with Terminal Selectivity. J. Am. Chem. Soc. 2013, 135, 19107. - PubMed
    4. Palmer WN; Diao T; Pappas I; Chirik PJ High-Activity Cobalt Catalysts for Alkene Hydroboration with Electronically Responsive Terpyridine and α-Diimine Ligands. ACS Catal. 2015, 5, 622.
    5. Ogawa T; Ruddy AJ; Sydora OL; Stradiotto M; Turculet L Cobalt- and Iron-Catalyzed Isomerization–Hydroboration of Branched Alkenes: Terminal Hydroboration with Pinacolborane and 1,3,2-Diazaborolanes. Organometallics 2017, 36, 417.
    6. Arthur P; England DC; Pratt BC; Whitman GM Addition of Hydrogen Cyanide to Unsaturated Compounds. J. Am. Chem. Soc. 1954, 76, 5364.
    7. Vilches-Herrera MV-H; Domke L; Börner A Armin Isomerization–Hydroformylation Tandem Reactions. ACS Catal. 2014, 4, 1706.
    8. Seayad A; Ahmed M; Klein H; Jackstell R; Gross T; Beller M Internal olefins to linear amines. Science 2002, 297, 1676. - PubMed

Publication types