English

• Over the past decades, radical-mediated difunctionalization of alkenes has emerged as a robust platform for constructing complex molecules from simple materials [1-11]. In this field, alkene functional-oximation represents a highly valued synthetic transformation, due to the importance of oxime scaffold in synthetic chemistry and pharmaceutical chemistry [12-20]. Remarkably, the early common strategy for this reaction was the radical coupling of alkenes with nitric oxide (NO) gas, which underwent the radical addition to C═C bond and the coupling with NO to provide the corresponding nitrosoalkane, followed by tautomerization to lead the final oxime product (Scheme 1a) [21-26]. However, the high toxicity, instability, and low solubility in common solvents of NO gas severely limit its application in organic synthesis [27,28]. A series of organic [NO] reagents, including N-nitrosamines/amides [29-33], nitroso alkanes [34-37], and nitrite esters [38-41], have been used as NO sources instead of NO gas for the synthesis of oximes via in situ generation of the persistent nitric oxide radical (Scheme 1a). In this context, the inexpensive and easily accessible tert-butyl nitrite (TBN) as a bifunctional reagent [42,43] triggered radical alkene difunctionalization has been exploited as a straightforward and efficient strategy for the rapid assembly of a wide range of structurally diverse oxime-containing compounds [44-54]. The reactive tert-butoxyl radical and NO radical, which showed the dual roles as the hydrogen atom transfer (HAT) reagent and the source of oximes, respectively, were generated by homolytic O—NO bond cleavage of TBN under high-energy ultraviolet light (UV) irradiation or elevated temperatures (Scheme 1b) [47-54]. Recently, Studer and co-workers reported a mild visible-light-driven radical silyloximation of electron-deficient alkenes with TBN and silanes, in which a light-promoted generated tert-butoxyl radical abstracts a hydrogen atom from silane to form silyl radical (Scheme 1c) [55]. Very recently, the Li group disclosed a visible-light-mediated radical sulfamoyloximation of alkenes using TBN as a bifunctional reagent [56]. Therefore, the development of novel visible-light-induced radical functional-oximation of alkenes with TBN as a bifunctional reagent, to efficiently access functionalized oxime compounds, remains highly desirable.

  Scheme 1

  

  Scheme 1.  Radical functional-oximation of alkenes.

  DownLoad: Full-Size Img PowerPoint

  On the other hand, organophosphorus compounds have found widespread applications in various fields, including catalysis, organic synthesis, medicinal chemistry, and materials science [57-63]. Consequently, the synthesis of organophosphorus molecules has attracted significant attention and notable progress has been made [64-70]. In this context, P-centered radical-triggered difunctionalization of alkenes via transition metal-catalysis, photocatalysis and electrochemistry, emerges as an ideal strategy [71-91]. Given the significance of oxime compounds and phosphorus functionalities, we hypothesized that radical phosphinoyloximation of alkenes with secondaryl phosphine oxides and TBN would be an efficient route to α-phosphinoyl oximes [92-95]. It should be mentioned that Zou and co-workers elegantly realized this transformation with a noble silver catalyst [96]. Herein, we report a visible-light-induced radical phosphinoyloximation of alkenes with secondaryl phosphine oxides and TBN under photocatalyst- and metal-free conditions (Scheme 1d). This reaction shows broad substrate scope and good functional group compatibility, yielding various α-phosphinoyl oximes in moderate to good yields with high stereoselectivities.

  We commenced the investigations using styrene (1a) and diphenylphosphine oxide (2a), in the presence of tert-butyl nitrite (TBN), as model substrates (Table 1). Encouragingly, after extensive screening of the reaction conditions, we succeeded in the desired phosphinoyloximation reaction using 2,4,6-collidine (1.0 equiv.) as base in DCM under irradiation of 40 W purple LEDs (Figs. S1 and S2 in Supporting information) at room temperature, affording the desired phosphinoyl oxime product 3 in 87% isolated yield with exclusive stereoselectivity (entry 1). The precise structure of 3 was unambiguously confirmed by X-ray crystallographic analysis (CCDC: 2354465), and the Z-stereoselectivity of oxime may be due to the intermolecular hydrogen-bonds between oxime and phosphinoyl functionalities. Notably, base was essential for this reaction as no desired product was detected in the absence of 2,4,6-collidine (entry 2). We proposed that the base may have a facilitative effect for the tautomerization of nitrosoalkane to oxime product. Various organic and inorganic bases were screened, but no improvement of the results was observed (entries 3–7). Then, the use of other solvents instead of DCM, such as DMSO, THF and toluene, resulted in diminished yields (entries 8–10). Control experiments confirmed that no desired product was obtained in the absence of visible light, and only 22% yield was afforded even upon increasing the temperature to 80 ℃ (entries 11 and 12). Other light sources, such as blue LEDs and white LEDs, gave lower reaction efficiencies relative to purple LEDs (entries 13 and 14).

  Table 1

  

  Table 1.  Optimization of the reaction conditions.^a

  DownLoad: CSV

  With the optimized conditions in hand, the alkene scope of this visible-light-induced phosphinoyloximation reaction was investigated (Scheme 2). A wide variety of styrene derivatives bearing both an electron-donating and electron-withdrawing group or two substituents at the different positions of benzene ring smoothly participated in this reaction to give the desired products 3–26 in moderate to good yields with high stereoselectivities. 1- and 2-vinylnaphthalene were also suitable for this reaction to produce the corresponding products 27 and 28 in 31% and 63% yields, respectively. Note that the introduction of a substituent at the ortho position of phenyl moiety had an obvious harmful influence on the reaction efficiencies (23, 24, 27), probably as a result of high steric hindrance. The alkenes bearing heterocycles such as pyridine, thiophene, benzofuran, and benzothiophene were found to be compatible with the present reaction conditions to provide the products 29–33 in 40%–93% yields. In addition to terminal alkenes, acyclic and cyclic internal alkenes were amenable to this protocol, albeit with low reaction efficiencies (34, 35), which might be due to the relatively slower addition rate of the phosphinoyl radical to double bond. A twofold phosphinoyloximation reaction of p-divinylbenzene was achieved to afford the product 36 in 55% yield. Notably, N-vinyl-2-pyrrolidone, -phthalimide and -carbazole proved to be suitable substrates in this reaction to generate the aminooxime products 37–39 in moderate yields. Moreover, a variety of electron-deficient alkenes, including acrylates, acrylamide, vinyl ketone, acrylonitrile, and vinyl sulfone, underwent this transformation smoothly to afford the corresponding products 40–45 in good yields, while a low stereoselectivity of 1.3:1 was observed for the reaction of acrylonitrile. Interestingly, the visible-light-induced phosphinoyloximation reaction of the allyl acrylate substrate, which contains two different types of carbon−carbon double bonds, preferentially occurred at the activated electron-deficient alkene rather than the unactivated one to give the product 41. When the unactivated aliphatic alkenes, such as 1-heptane and 4-phenyl-1-butane, were utilized in this reaction, no desired products were observed at the current stage. To demonstrate the potential applicability of this protocol, we examined more complex substrates for the phosphinoyloximation reaction. A variety of natural-products and drug derived alkenes reacted well, giving the desired products 46–54 in good yields.

  Scheme 2

  

  Scheme 2.  Substrate scope of alkenes. The reactions were performed on a 0.2 mmol scale. Isolated yields. ^a The reaction was carried out with 1,4-divinylbenzene 1ah (0.2 mmol), 2a (0.72 mmol, 3.6 equiv.), ^tBuONO (1.2 mmol, 6.0 equiv.), 2,4,6-collidine (0.4 mmol, 2.0 equiv.) and DCM (2 mL).

  DownLoad: Full-Size Img PowerPoint

  As shown in Scheme 3, we next explored the scope of secondary phosphine oxides. A variety of monosubstituted and disubstituted diarylphosphine oxides took part in the reaction to afford the corresponding phosphinoyl oxime products 55−67 in good yields. Furthermore, the phosphine oxides substituted with naphthyl groups or heterocycles such as thiophene and benzothiophene were found to be compatible with this phosphinoyloximation approach. The asymmetric phosphine oxides such as substituted phenyl- or alkylphenylphosphine oxides were also suitable substrates to deliver the corresponding products 72–76 in 76%–84% yields. Note that the reaction of 6H-dibenz[c,e][1,2]oxaphosphorin 6-oxide (DOPO) proceeded smoothly to provide the desired product 77 in moderate yield, while dicyclohexylphosphine oxide, ethyl phenylphosphinate, and diethyl phosphite failed to participate in the present phosphinoyloximation reaction.

  Scheme 3

  

  Scheme 3.  Substrate scope of secondary phosphine oxides. The reactions were performed on a 0.2 mmol scale. Isolated yields.

  DownLoad: Full-Size Img PowerPoint

  To further demonstrate the practical applicability of this protocol, we conducted a gram-scale reaction and explored the further transformations of α-phosphinoyl oxime product (Scheme 4). The model reaction of 1a and 2a was carried out on a 5.0 mmol scale under the optimal conditions, and 1.16 g desired product 3 was obtained in 69% yield. Then, the O-acetylations of oxime functionality of 3 with acetyl and benzoyl chlorides gave the oxime esters 78 and 79 in 80% and 73% yields, respectively. The phosphine oxide group in 3 could not only undergo the oxygen-sulfur exchange process to generate phosphine sulfide 80 in 56% yield in the presence of Lawesson reagent, but also be readily reduced by Si—H reagent to afford trivalent phosphine compound 81 in 63% yield. Furthermore, the rhodium-catalyzed aromatic C—H bond functionalization of 3 with oxime as directing group afforded the isoquinoline derivative 82 in 54% yield [32], followed by the reduction and protection with borane to obtain phosphine compound 83 as a new bidentate P, N-ligand precursor in good yield.

  Scheme 4

  

  Scheme 4.  Utility of the reaction methodology.

  DownLoad: Full-Size Img PowerPoint

  To gain some insights into this reaction, mechanistic studies were conducted. First, UV–vis absorbance spectra revealed that TBN had a noticeable absorption under our visible LEDs (Scheme 5a). Second, when the radical scavenger 2,2,6,6-tetramethylpiperidine-1-oxy (TEMPO) or 2,6-di-tert-butyl-4-methylphenol (BHT) was added to the model reaction, the formation of product 3 was suppressed completely, and the adducts 84 and 85 of phosphinoyl radical by TEMPO and BHT were isolated in 35% and 26% yields, respectively, which indicated the phosphinoyl radical was involved in this reaction (Scheme 5b). Finally, a radical clock experiment using vinyl cyclopropane 86 provided the ring-opening product 87 in 24% yield, suggesting a benzyl radical might be generated after P-centered radical addition to the alkene (Scheme 5c).

  Scheme 5

  

  Scheme 5.  Mechanistic investigations.

  DownLoad: Full-Size Img PowerPoint

  Based on the above experiment results and previous studies [44-56,71-91], a possible reaction mechanism was proposed in Scheme 6. First, visible-light-induced homolytic cleavage of the O—NO bond of TBN produces a reactive tert-butoxyl radical (^tBuO•) and the persistent NO radical. The subsequent HAT from diphenylphosphine oxide 2a to ^tBuO• [97], generates the phosphinoyl radical Ⅰ with the release of byproduct ^tBuOH, which was detected by GC in an amount comparable to the product 3 (Figs. S6–S8 in Supporting information). Then, the addition of radical Ⅰ to styrene 1a affords the benzyl radical intermediate Ⅱ, which is trapped by NO radical through a radical/radical cross-coupling process governed by the persistent radical effect [98]. Finally, the rapid tautomerization of nitrosoalkane Ⅲ delivers the final phosphinoyl oxime product 3.

  Scheme 6

  

  Scheme 6.  Proposed reaction mechanism.

  DownLoad: Full-Size Img PowerPoint

  In conclusion, we have developed an efficient visible-light-induced radical phosphinoyloximation of alkenes with secondary phosphine oxides and TBN. Under photocatalyst- and metal-free conditions, various α-phosphinoyl oximes were afforded in moderate to good yields and high stereoselectivities with broad substrate scope and good functional group compatibility. This method can be readily scalable and the phosphinoyl oxime products could serve as valuable building blocks for further transformations. Critical to this success is TBN's dual roles as HAT reagent and the source of oximes. We anticipate that this strategy for photochemical generation of phosphinoyl radicals with TBN provides a new perspective to rapidly construct organophosphorus compounds.

  Declaration of competing interest

  The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

  CRediT authorship contribution statement

  Huaixiang Yang: Methodology, Formal analysis, Data curation. Miao-Miao Li: Writing – original draft, Project administration. Aijun Zhang: Methodology, Formal analysis, Data curation. Jiefei Guo: Methodology, Formal analysis, Data curation. Yongqi Yu: Writing – review & editing, Project administration. Wei Ding: Writing – review & editing, Project administration, Conceptualization.

  Acknowledgments

  We gratefully acknowledge the financial support from the National Natural Science Foundation of China (Nos. 22201265, 22201264) and the China Postdoctoral Science Foundation (Nos. 2022M710133, 2022TQ0287).

  Supplementary materials

  Supplementary material associated with this article can be found, in the online version, at doi:10.1016/j.cclet.2024.110425.

  
  
• 1. [1]

     M.Y. Cao, X. Ren, Z. Lu, Tetrahedron Lett. 56 (2015) 3732–3742. doi: 10.1016/j.tetlet.2015.04.091

  2. [2]

     X.W. Lan, N.X. Wang, Y. Xing, Eur. J. Org. Chem. 2017 (2017) 5821–5851. doi: 10.1002/ejoc.201700678

  3. [3]

     T. Koike, M. Akita, Chem 4 (2018) 409–437. doi: 10.1016/j.chempr.2017.11.004

  4. [4]

     J. Lin, R.J. Song, M. Hu, J.H. Li, Chem. Rec. 19 (2018) 440–451. doi: 10.1002/tcr.201800053

  5. [5]

     X. Bao, J. Li, W. Jiang, C. Huo, Synthesis 51 (2019) 4507–4530. doi: 10.1055/s-0039-1690987

  6. [6]

     H. Yao, W. Hu, W. Zhang, Molecules 26 (2020) 105. doi: 10.3390/molecules26010105

  7. [7]

     S.O. Badir, G.A. Molander, Chem 6 (2020) 1327–1339. doi: 10.1016/j.chempr.2020.05.013

  8. [8]

     H. Jiang, A. Studer, Chem. Soc. Rev. 49 (2020) 1790–1811. doi: 10.1039/c9cs00692c

  9. [9]

     Z.L. Li, G.C. Fang, Q.S. Gu, X.Y. Liu, Chem. Soc. Rev. 49 (2020) 32–48. doi: 10.1039/c9cs00681h

  10. [10]

      S. Zhu, X. Zhao, H. Li, L. Chu, Chem. Soc. Rev. 50 (2021) 10836–10856. doi: 10.1039/d1cs00399b

  11. [11]

      P. Gao, Y.J. Niu, F. Yang, L.N. Guo, X.H. Duan, Chem. Commun. 58 (2022) 730–746. doi: 10.1039/d1cc05730h

  12. [12]

      K. Katakawa, M. Kitajima, N. Aimi, et al., J. Org. Chem. 70 (2004) 658–663.

  13. [13]

      J.T. Bagdanoff, M.S. Donoviel, A. Nouraldeen, et al., J. Med. Chem. 53 (2010) 8650–8662. doi: 10.1021/jm101183p

  14. [14]

      C. Kornhaaß, J. Li, L. Ackermann, J. Org. Chem. 77 (2012) 9190–9198. doi: 10.1021/jo301768b

  15. [15]

      Y. Wei, N. Yoshikai, J. Am. Chem. Soc. 135 (2013) 3756–3759. doi: 10.1021/ja312346s

  16. [16]

      Y. Xu, W. Hu, X. Tang, et al., Chem. Commun. 51 (2015) 6843–6846. doi: 10.1039/C5CC01661D

  17. [17]

      N. Liu, L. Song, M. Liu, et al., Chem. Sci. 7 (2016) 482–488. doi: 10.1039/C5SC03021H

  18. [18]

      D.Q. Dong, J.C. Song, S.H. Yang et al., Chin. Chem. Lett. 33 (2022) 1199–1206. doi: 10.1016/j.cclet.2021.08.067

  19. [19]

      S. Yang, Y. Wang, W. Xu, et al., Org. Lett. 25 (2023) 8834–8838. doi: 10.1021/acs.orglett.3c03526

  20. [20]

      T. Zou, Y.S. He, R. Liu, et al., Chin. Chem. Lett. 34 (2023) 107822–107826. doi: 10.1016/j.cclet.2022.107822

  21. [21]

      K. Kato, T. Mukaiyama, Chem. Lett. 19 (1990) 1395–1398. doi: 10.1246/cl.1990.1395

  22. [22]

      M. Kijima, H. Yamashita, T. Sato, J. Organomet. Chem. 426 (1992) 399–404. doi: 10.1016/0022-328X(92)83072-P

  23. [23]

      T. Okamoto, K. Kobayashi, S. Oka, S. Tanimoto, J. Org. Chem. 52 (2002) 5089–5092.

  24. [24]

      C. de Salas, O. Blank, M.R. Heinrich, Chem. Eur. J. 17 (2011) 9306–9310. doi: 10.1002/chem.201101565

  25. [25]

      C. de Salas, M.R. Heinrich, Green Chem. 16 (2014) 2982–2987. doi: 10.1039/C3GC42432D

  26. [26]

      J. Hartung, Chem. Rev. 109 (2009) 4500–4517. doi: 10.1021/cr900085j

  27. [27]

      P. Scharlin, R. Battino, E. Silla, I. Tuñón, J.L. Pascual-Ahuir, Pure Appl. Chem. 70 (1998) 1895–1904. doi: 10.1351/pac199870101895

  28. [28]

      B. Weinberger, Toxicol. Sci. 59 (2001) 5–16. doi: 10.1093/toxsci/59.1.5

  29. [29]

      P.F. Yuan, T. Huang, J. He, et al., Org. Chem. Front. 8 (2021) 5785–5792. doi: 10.1039/d1qo01101d

  30. [30]

      Z. Wang, N. Wierich, J. Zhang, C.G. Daniliuc, A. Studer, J. Am. Chem. Soc. 145 (2023) 8770–8775. doi: 10.1021/jacs.3c01129

  31. [31]

      H. Lan, X. Huo, Y. Jia, D. Wang, Org. Lett. 26 (2024) 1011–1016. doi: 10.1021/acs.orglett.3c04085

  32. [32]

      P.F. Yuan, X.T. Huang, L.H. Long, et al., Angew. Chem. Int. Ed. 63 (2024) e202317968. doi: 10.1002/anie.202317968

  33. [33]

      J.W. Sang, H. Chen, Y. Zhang, J. Wang, W.D. Zhang, Green Chem. 26 (2024) 7849–7856. doi: 10.1039/d4gc01976h

  34. [34]

      H. Chakrapani, M.D. Bartberger, E.J. Toone, J. Org. Chem. 74 (2009) 1450–1453. doi: 10.1021/jo802517t

  35. [35]

      D. Zheng, S. Plöger, C.G. Daniliuc, A. Studer, Angew. Chem. Int. Ed. 60 (2021) 8547–8551. doi: 10.1002/anie.202016955

  36. [36]

      R. Gao, F. Wang, X. Geng, C.Y. Li, L. Wang, Org. Lett. 24 (2022) 7118–7122. doi: 10.1021/acs.orglett.2c02703

  37. [37]

      S. Plöger, C. Mück-Lichtenfeld, C.G. Daniliuc, A. Studer, Chem. Sci. 13 (2022) 9749–9754. doi: 10.1039/d2sc03860a

  38. [38]

      D.H.R. Barton, J.M. Beaton, J. Am. Chem. Soc. 82 (1960) 2641. doi: 10.1021/ja01495a062

  39. [39]

      D.H.R. Barton, J.M. Beaton, L.E. Geller, M.M. Pechet, J. Am. Chem. Soc. 82 (1960) 2640–2641. doi: 10.1021/ja01495a061

  40. [40]

      D.H.R. Barton, J.M. Beaton, L.E. Geller, M.M. Pechet, J. Am. Chem. Soc. 83 (1961) 4076–4083. doi: 10.1021/ja01480a030

  41. [41]

      G. Majetich, K. Wheless, Tetrahedron 51 (1995) 7095–7129. doi: 10.1016/0040-4020(95)00406-X

  42. [42]

      E. Piers, Pure Appl. Chem. 60 (1988) 107–114. doi: 10.1351/pac198860010107

  43. [43]

      H.M. Huang, P. Bellotti, J. Ma, T. Dalton, F. Glorius, Nat. Rev. Chem. 5 (2021) 301–321. doi: 10.1038/s41570-021-00266-5

  44. [44]

      A. Dahiya, A.K. Sahoo, T. Alam, B.K. Patel, Chem. Asian J. 14 (2019) 4454–4492. doi: 10.1002/asia.201901072

  45. [45]

      N.G. Khaligh, Mini-Rev. Org. Chem. 17 (2020) 3–25. doi: 10.2174/1570193x15666181029141019

  46. [46]

      Z.L. Chen, Q.Q. Li, A. Studer, J. Xuan, Sci. China Chem. 68 (2025) 118–133. doi: 10.1007/s11426-024-2096-6

  47. [47]

      J. Yang, Y.Y. Liu, R.J. Song, Z.H. Peng, J.H. Li, Adv. Synth. Catal. 358 (2016) 2286–2292. doi: 10.1002/adsc.201600109

  48. [48]

      B. Wang, L. Tang, L. Liu, et al., Green Chem. 19 (2017) 5794–5799. doi: 10.1039/C7GC03051G

  49. [49]

      J. Wysocki, J.H. Teles, R. Dehn, et al., ChemPhotoChem 2 (2018) 22–26. doi: 10.1002/cptc.201700151

  50. [50]

      L. Chen, Z. Wang, H. Liu, X. Li, B. Wang, Chem. Commun. 58 (2022) 9152–9155. doi: 10.1039/d2cc02823a

  51. [51]

      Y. Liu, J. Cao, M. Zhang, et al., J. Org. Chem. 88 (2023) 15311–15317. doi: 10.1021/acs.joc.3c01815

  52. [52]

      Y. Tang, Y. Yang, Q. Zhou, et al., Org. Biomol. Chem. 21 (2023) 5254–5264. doi: 10.1039/d3ob00630a

  53. [53]

      Y. Zhao, X. Li, S.L. Homölle, B. Wang, L. Ackermann, Chem. Sci. 15 (2024) 1117–1122. doi: 10.1039/d3sc05946d

  54. [54]

      X. m. Chen, J. Huang, J. Pan, et al., Org. Lett. 26 (2024) 3883–3888. doi: 10.1021/acs.orglett.4c01038

  55. [55]

      S. Plöger, A. Studer, Org. Lett. 24 (2022) 8568–8572. doi: 10.1021/acs.orglett.2c03644

  56. [56]

      W. Li, Z. Huang, D. Zhong, H. Li, Org. Lett. 26 (2024) 2062–2067. doi: 10.1021/acs.orglett.4c00314

  57. [57]

      P.C.J. Kamer, P.W.N.M. van Leeuwen, J.N.H. Reek, Acc. Chem. Res. 34 (2001) 895–904. doi: 10.1021/ar000060+

  58. [58]

      P.W.N.M. van Leeuwen, P.C.J. Kamer, C. Claver, O. Pàmies, M. Diéguez, Chem. Rev. 111 (2011) 2077–2118. doi: 10.1021/cr1002497

  59. [59]

      C. Queffélec, M. Petit, P. Janvier, D.A. Knight, B. Bujoli, Chem. Rev. 112 (2012) 3777–3807. doi: 10.1021/cr2004212

  60. [60]

      G.P. Horsman, D.L. Zechel, Chem. Rev. 117 (2017) 5704–5783. doi: 10.1021/acs.chemrev.6b00536

  61. [61]

      H. Ni, W.L. Chan, Y. Lu, Chem. Rev. 118 (2018) 9344–9411. doi: 10.1021/acs.chemrev.8b00261

  62. [62]

      H. Guo, Y.C. Fan, Z. Sun, Y. Wu, O. Kwon, Chem. Rev. 118 (2018) 10049–10293. doi: 10.1021/acs.chemrev.8b00081

  63. [63]

      P. Finkbeiner, J.P. Hehn, C. Gnamm, J. Med. Chem. 63 (2020) 7081–7107. doi: 10.1021/acs.jmedchem.0c00407

  64. [64]

      K. Moonen, I. Laureyn, C.V. Stevens, Chem. Rev. 104 (2004) 6177–6216. doi: 10.1021/cr030451c

  65. [65]

      C.S. Demmer, N. Krogsgaard-Larsen, L. Bunch, Chem. Rev. 111 (2011) 7981–8006. doi: 10.1021/cr2002646

  66. [66]

      J.L. Montchamp, Acc. Chem. Res. 47 (2014) 77–87. doi: 10.1021/ar400071v

  67. [67]

      H. Sun, Y. Li, W. Liu, Y. Zheng, Z. He, Chin. Chem. Lett. 29 (2018) 1625–1628. doi: 10.1016/j.cclet.2018.01.026

  68. [68]

      L. Chen, X.Y. Liu, Y.X. Zou, Adv. Synth. Catal. 362 (2020) 1724–1818. doi: 10.1002/adsc.201901540

  69. [69]

      J.D. Gbubele, T.K. Olszewski, Org. Biomol. Chem. 19 (2021) 2823–2846. doi: 10.1039/d1ob00124h

  70. [70]

      B. Wang, L. Sun, Q. Cao, et al., Chin. Chem. Lett. 35 (2024) 109617. doi: 10.1016/j.cclet.2024.109617

  71. [71]

      D. Leca, L. Fensterbank, E. Lacôte, M. Malacria, Chem. Soc. Rev. 34 (2005) 858–865. doi: 10.1039/b500511f

  72. [72]

      Y. Gao, G. Tang, Y. Zhao, Phosphorus, Sulfur, Silicon Relat. Elem. 192 (2017) 589–596. doi: 10.1080/10426507.2017.1295965

  73. [73]

      B.G. Cai, J. Xuan, W.J. Xiao, Sci. Bull. 64 (2019) 337–350. doi: 10.1016/j.scib.2019.02.002

  74. [74]

      C. Li, J. Wang, S.D. Yang, Chem. Commun. 57 (2021) 7997–8002. doi: 10.1039/d1cc02604f

  75. [75]

      J. Liu, H.Z. Xiao, Q. Fu, D.G. Yu, Chem. Synth. 1 (2021) 9. doi: 10.20517/cs.2021.14

  76. [76]

      Y. Niu, S. -D. Yang, Chem. Synth. 1 (2021) 12.

  77. [77]

      C. Zhang, Z. Li, L. Zhu, et al., J. Am. Chem. Soc. 135 (2013) 14082–14085. doi: 10.1021/ja408031s

  78. [78]

      W.J. Yoo, S. Kobayashi, Green Chem. 15 (2013) 1844–1848. doi: 10.1039/c3gc40482j

  79. [79]

      G. Zhang, L. Fu, P. Chen, J. Zou, G. Liu, Org. Lett. 21 (2019) 5015–5020. doi: 10.1021/acs.orglett.9b01607

  80. [80]

      Y.H. Li, C.H. Wang, S.Q. Gao, F.M. Qi, S.D. Yang, Chem. Commun. 55 (2019) 11888–11891. doi: 10.1039/c9cc06075h

  81. [81]

      Q. Fu, Z.Y. Bo, J.H. Ye, et al., Nat. Commun. 10 (2019) 3592. doi: 10.1038/s41467-019-11528-8

  82. [82]

      W.Q. Liu, T. Lei, S. Zhou, et al., J. Am. Chem. Soc. 141 (2019) 13941–13947. doi: 10.1021/jacs.9b06920

  83. [83]

      N. Fu, L. Song, J. Liu, et al., J. Am. Chem. Soc. 141 (2019) 14480–14485. doi: 10.1021/jacs.9b03296

  84. [84]

      W. Yang, B. Li, M. Zhang, et al., Chin. Chem. Lett. 31 (2020) 1313–1316. doi: 10.1016/j.cclet.2019.10.022

  85. [85]

      P.Z. Wang, W.J. Xiao, J.R. Chen, Nat. Rev. Chem. 7 (2022) 35–50. doi: 10.1038/s41570-022-00441-2

  86. [86]

      Q. Cao, M.M. Li, X. Mao, Q.Q. Zhou, W. Ding, Org. Lett. 26 (2024) 4678–4683. doi: 10.1021/acs.orglett.4c01422

  87. [87]

      H. Zhang, X. Sun, C. Ma, et al., ACS Catal. 14 (2024) 3115–3127. doi: 10.1021/acscatal.3c05154

  88. [88]

      G.Q. Li, Z.Q. Li, M. Jiang, et al., Angew. Chem. Int. Ed. 63 (2024) e202405560. doi: 10.1002/anie.202405560

  89. [89]

      L. Liu, Y. Wu, C. Xiang, J.T. Yu, C. Pan, Chem. Commun. 60 (2024) 4687–4690. doi: 10.1039/d4cc00608a

  90. [90]

      X.M. Chen, L. Song, J. Pan, et al., Chin. Chem. Lett. 35 (2024) 110112. doi: 10.1016/j.cclet.2024.110112

  91. [91]

      D. Liang, P. Gao, Z. Zhang, W. Xiao, J. Chen, Green Synth. Catal. 5 (2024), doi: 10.1016/j.gresc.2024.01.002.

  92. [92]

      A.V. Il'yasov, Biophysics 58 (2013) 167–171. doi: 10.1134/S0006350913020103

  93. [93]

      J. Francos, J. Borge, S. Conejero, V. Cadierno, Eur. J. Inorg. Chem. 2018 (2018) 3176–3186. doi: 10.1002/ejic.201800398

  94. [94]

      Y.A. Naumovich, S.L. Ioffe, A.Y. Sukhorukov, J. Org. Chem. 84 (2019) 7244–7254. doi: 10.1021/acs.joc.9b00924

  95. [95]

      H. Lan, Y. Su, Y. Chen, X. He, D. Wang, Org. Chem. Front. 11 (2024) 4207–4213. doi: 10.1039/d4qo00636d

  96. [96]

      J. Zou, Z. Ying, P. Zhang, Z. Tao, J. Li, Patent, CN111039978B, 2017.

  97. [97]

      J. Shen, B. Xiao, Y. Hou, et al., Adv. Synth. Catal. 361 (2019) 5198–5209. doi: 10.1002/adsc.201900873

  98. [98]

      D. Leifert, A. Studer, Angew. Chem. Int. Ed. 59 (2020) 74–108. doi: 10.1002/anie.201903726

• 

  Scheme 1  Radical functional-oximation of alkenes.

  下载: 全尺寸图片 幻灯片
  

  Scheme 2  Substrate scope of alkenes. The reactions were performed on a 0.2 mmol scale. Isolated yields. ^a The reaction was carried out with 1,4-divinylbenzene 1ah (0.2 mmol), 2a (0.72 mmol, 3.6 equiv.), ^tBuONO (1.2 mmol, 6.0 equiv.), 2,4,6-collidine (0.4 mmol, 2.0 equiv.) and DCM (2 mL).

  下载: 全尺寸图片 幻灯片
  

  Scheme 3  Substrate scope of secondary phosphine oxides. The reactions were performed on a 0.2 mmol scale. Isolated yields.

  下载: 全尺寸图片 幻灯片
  

  Scheme 4  Utility of the reaction methodology.

  下载: 全尺寸图片 幻灯片
  

  Scheme 5  Mechanistic investigations.

  下载: 全尺寸图片 幻灯片
  

  Scheme 6  Proposed reaction mechanism.

  下载: 全尺寸图片 幻灯片

  Table 1.  Optimization of the reaction conditions.^a

  下载: 导出CSV
•