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. 2018 Nov 16;20(22):7345-7350.
doi: 10.1021/acs.orglett.8b03345. Epub 2018 Nov 8.

Photocatalytic Oxyamination of Alkenes: Copper(II) Salts as Terminal Oxidants in Photoredox Catalysis

Nicholas L Reed  1 , Madeline I Herman  1 , Vladimir P Miltchev  1 , Tehshik P Yoon  1
Affiliations

Photocatalytic Oxyamination of Alkenes: Copper(II) Salts as Terminal Oxidants in Photoredox Catalysis

Nicholas L Reed et al. Org Lett. .

Abstract

A photocatalytic method for the oxyamination of alkenes using simple nucleophilic nitrogen atom sources in place of prefunctionalized electrophilic nitrogen atom donors is reported. Copper(II) is an inexpensive, practical, and uniquely effective terminal oxidant for this process. In contrast to oxygen, peroxides, and similar oxidants commonly utilized in non-photochemical oxidative methods, the use of copper(II) as a terminal oxidant in photoredox reactions avoids the formation of reactive heteroatom-centered radical intermediates that can be incompatible with electron-rich functional groups. As a demonstration of the generality of this concept, it has been shown that diamination and deoxygenation reactions can also be accomplished using similar photooxidative conditions.

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Figures

Figure 1.
Figure 1.
Oxyamination reactions with and without preoxidized nitrogen atom donors.
Scheme 1.
Scheme 1.
Diverting photogenerated radical intermediates toward net oxidative functionalization reactions.
Scheme 2.
Scheme 2.
Scope studies for photocatalytic oxyamination reactionsa a Unless otherwise noted, all reactions were conducted using 2.5 mol % 7, 1.2 equiv Cu(TFA)2 in degassed CH2Cl2 and irradiated with a 15 W blue LED flood lamp for 15–48 h. Isolated yields are reported. b Reaction time 48 h. c Reaction time 72 h. d Reaction time 7 days.
Scheme 3.
Scheme 3.
Experiments supporting the proposed mechanism.
Scheme 4.
Scheme 4.
Working mechanistic hypothesis and extension to alkene difunctionalization a Reactions conducted using MesAcrMe+BF4− as the photocatalyst and Cu(OAc)2 as the terminal oxidant. b Reactions conducted using 4 equiv of alcohol, TPPT as photocatalyst, and Cu(TFA)2 as terminal oxidant.
See this image and copyright information in PMC

References

    1. For recent reviews of alkene oxyamination, see: O’Brien P “Sharpless Asymmetric Aminohydroxylation: Scope, Limitations, and Use in Synthesis,” Angew. Chem. Int. Ed 1999, 38, 326–329. - PubMed
    2. Nilov D; Reiser O “The Sharpless Asymmetric Aminohydroxylation – Scope and Limitation,” Adv. Synth. Catal 2002, 344, 1169–1173.
    3. Bodkin JA; McLeod MD “The Sharpless asymmetric aminohydroxylation,” J. Chem. Soc., Perkin Trans 1 2002, 2733–2746.
    4. Donohoe TJ; Callens CKA; Flores A; Lacy AR; Rathi AH “Recent Developments in Methodology for the Direct Oxyamination of Olefins,” Chem. Eur. J 2011, 17, 58–76. - PubMed
    1. For selected examples of alkene oxyaminations without preoxidized nitrogen atom donors, see: Alexanian EJ; Lee C; Sorensen EJ “Palladium-Catalyzed Ring-Forming Aminoacetoxylation of Alkenes,” J. Am. Chem. Soc 2005, 127, 7690–7691. - PubMed
    2. Liu G; Stahl SS “Highly Regioselective Pd-Catalyzed Intermolecular Aminoacetoxylation of Alkenes and Evidence for cis-Aminopalladation and SN2 C–O Bond Formation,” J. Am. Chem. Soc. 2006, 128, 7179–7181. - PubMed
    3. Fuller PH; Kim J-W; Chemler SR “Copper Catalyzed Enantioselective Intramolecular Aminooxygenation of Alkenes,” J. Am. Chem. Soc. 2008, 130, 17638–17639. - PMC - PubMed
    4. Lovick HM; Michael FE “Metal-Free Highly Regioselective Aminotrifluoroacetoxylation of Alkenes,” J. Am. Chem. Soc. 2010, 132, 1249–1251. - PubMed
    5. Wardrop DJ; Bowen EG; Forslund RE; Sussman AD; Weerasekera SL “Intramolecular Oxamidation of Unsaturated O-Alkyl Hydroxamates: A Remarkably Versatile Entry to Hydroxy Lactams,” J. Am. Chem. Soc. 2010, 132, 1188–1189. - PMC - PubMed
    6. de Haro T; Nevado C “Flexible Gold-Catalyzed Regioselective Oxidative Difunctionalization of Unactivated Alkenes,” Angew. Chem. Int. Ed. 2011, 50, 906–910. - PubMed
    7. Farid U; Wirth T “Highly Stereoselective Metal-Free Oxyaminations Using Chiral Hypervalent Iodine Reagents,” Angew. Chem. Int. Ed. 2012, 51, 3462–3465. - PubMed
    8. Shen H-C; Wu Y-F; Zhang Y; Fan L-F; Han Z-Y; Gong L-Z “Palladium-Catalyzed Asymmetric Aminohydroxylation of 1,3-Dienes,” Angew. Chem. Int. Ed. 2018, 57, 2372–2376. - PubMed
    9. Wu F; Stewart S; Ariyarathna JP; Li W “Aerobic Copper-Catalyzed Alkene Oxyamination for Amino Lactone Synthesis,” ACS Catal. 2018, 8, 1921–1925.
    1. For reviews, see: Narayanam JMR; Stephenson CRJ “Visible light photoredox catalysis: applications in organic synthesis,” Chem. Soc. Rev 2011, 40, 102–113. - PubMed
    2. Prier CK; Rankic DA; MacMillan DWC “Visible Light Photoredox Catalysis with Transition Metal Complexes: Applications in Organic Synthesis,” Chem. Rev 2013, 113, 5322–5363. - PMC - PubMed
    3. Romero NA; Nicewicz DA “Organic Photoredox Catalysis,“ Chem. Rev 2016, 116, 10075–10166. - PubMed
    4. Twilton J; Le C; Zhang P; Shaw MH; Evans RW; MacMillan DWC “The merger of transition metal and photocatalysis” Nature Rev. Chem 2017, 1, 0052.
    5. Zou YQ; Hörmann FM; Bach T “Iminium and enamine catalysis in enantioselective photochemical reactions,” Chem. Soc. Rev 2018, 47, 278–290. - PMC - PubMed
    6. Silvi M; Melchiorre P “Enhancing the potential of enantioselective organocatalysis with light,” Nature 2018, 554, 41–49. - PubMed
    1. Rueda-Becerril M; Mahé O; Drouin M; Majewski MB; West JF ; Wolf MO; Sammis GM; Paquin JF “Direct C-F bond formation using photoredox catalysis,” J. Am. Chem. Soc 2014, 136, 2637–2641. - PubMed
    2. Ventre S; Petronijevic FR; MacMillan DWC “Decarboxylative Fluorination of Aliphatic Carboxylic Acids via Photoredox Catalysis,” J. Am. Chem. Soc. 2015, 137, 5654–5657. - PMC - PubMed
    3. Griffin JD; Cavanaugh CL; Nicewicz DA “Reversing the Regioselectivity of Halofunctionalization Reactions through Cooperative Photoredox and Copper Catalysis,” Angew. Chem. Int. Ed 2017, 56, 2097–2100. - PMC - PubMed
    4. Davies J; Sheikh NS; Leonori D “Photoredox Imino Functionalizations of Olefins,” Angew. Chem. Int. Ed. 2017, 56, 13361–13365. - PMC - PubMed
    1. Allen LJ; Cabrera PJ; Lee M; Sanford MS “N-Acyloxyphthalimides as Nitrogen Radical Precursors in the Visible Light Photocatalyzed Room Temperature C–H Amination of Arenes and Heteroarenes,” J. Am. Chem. Soc. 2014, 136, 5607–5610. - PMC - PubMed
    2. Greulich TW; Daniliuc CG; Studer A “N-Aminopyridinium Salts as Precursors for N-Centered Radicals – Direct Amidation of Arenes and Heteroarenes,” Org. Lett. 2015, 17, 254–257. - PubMed
    3. Brachet E; Ghosh T; Ghosh I; Konig B “Visible light C–H amidation of heteroarenes with benzoyl azides,” Chem. Sci. 2015, 6, 987–992. - PMC - PubMed
    4. Rabet PTG; Fumagalli G; Boyd S; Greaney MF “Benzylic C–H Azidation Using the Zhdankin Reagent and a Copper Photoredox Catalyst,” Org. Lett. 2016, 18, 1646–1649. - PubMed

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