Subscribe to RSS
DOI: 10.1055/s-0037-1610279
Organic Photoredox Catalysis for Pschorr Reaction: A Metal-Free and Mild Approach to 6H-Benzo[c]chromenes
Financial support from the National Natural Science Foundation of China (NO 21302130 and 21676166) and the Science Technology Department of Zhejiang Province (NO 2014C31141) are acknowledged with thanks.Publication History
Received: 30 July 2018
Accepted after revision: 22 August 2018
Publication Date:
12 September 2018 (online)
![](https://www.thieme-connect.de/media/synlett/201817/lookinside/thumbnails/st-2018-r0486-l_10-1055_s-0037-1610279-1.jpg)
Abstract
An expedient organic photoredox Pschorr reaction has been developed that opens up a synthetic route to 6H-benzo[c]chromenes. The process can be performed under mild conditions by using eosin Y as a photoredox catalyst and acetonitrile as the solvent. The diazonium salts can be either preformed or generated in situ from the corresponding amines with t-BuONO. The process is amenable to gram-sale synthesis of 6H-benzo[c]chromenes, which can be further transformed into both 6H-benzo[c]chromen-6-ones through oxidation or to 6H-benzo[c]chromen-6-amine through sp3 C–H bond amination. The protocol provides an attractive route for the synthesis of a library of 6H-benzo[c]chromes.
Key words
organic photoredox catalysis - Pschorr reaction - diazonium salts - benzochromenes - C–H bond functionalizationSupporting Information
- Supporting information for this article is available online at https://doi.org/10.1055/s-0037-1610279.
- Supporting Information
-
References and Notes
- 1a Wang C.-S. Dixneuf PH. Soulé J.-F. Chem. Rev. 2018; 118: 7532
- 1b Zhang M. Zhu C. Ye L.-W. Synthesis 2017; 49: 1150
- 1c Xie J. Jin H. Hashmi AS. K. Chem. Soc. Rev. 2017; 46: 5193
- 1d Romero NA. Nicewicz DA. Chem. Rev. 2016; 116: 10075
- 1e Shaw MH. Twilton J. MacMillan DW. C. J. Org. Chem. 2016; 81: 6898
- 1f Chen J.-R. Hu X.-Q. Lu L.-Q. Xiao W.-J. Acc. Chem. Res. 2016; 49: 1911
- 1g Ghosh I. Marzo L. Das A. Shaikh R. König B. Acc. Chem. Res. 2016; 49: 1566
- 1h Tellis JC. Kelly CB. Primer DN. Jouffroy M. Patel NR. Molander GA. Acc. Chem. Res. 2016; 49: 1429
- 1i Courant T. Masson G. J. Org. Chem. 2016; 81: 6945
- 1j Koike T. Akita M. Inorg. Chem. Front. 2014; 1: 562
- 1k Prier CK. Rankic DA. MacMillan DW. C. Chem. Rev. 2013; 113: 5322
- 1l Narayanam JM. R. Stephenson CR. J. Chem. Soc. Rev. 2011; 40: 102
- 2a Sha W. Deng L. Ni S. Mei H. Han J. Pan Y. ACS Catal. 2018; 8: 7489
- 2b Key RJ. Vannucci AK. Organometallics 2018; 37: 1468
- 2c Liang L. Xie M.-S. Wang H.-X. Niu H.-Y. Qu G.-R. J. Org. Chem. 2017; 82: 5966
- 2d Um J. Yun H. Shin S. Org. Lett. 2016; 18: 484
- 2e Chen Y. Feng G. Org. Biomol. Chem. 2015; 13: 4260
- 3a Bai Q.-F. Jin C. He J.-Y. Feng G. Org. Lett. 2018; 20: 2172
- 3b Ouyang X.-H. Cheng J. Li J.-H. Chem. Commun. 2018; 54: 8745
- 3c ElMarrouni A. Ritts CB. Balsells J. Chem. Sci. 2018; 9: 6639
- 3d An X.-D. Yu S. Synthesis 2018; 50: 3387
- 3e Xu G.-Q. Xu J.-T. Feng Z.-T. Liang H. Wang Z.-Y. Qin YQ. Xu P.-F. Angew. Chem. Int. Ed. 2018; 57: 5110
- 3f Shi L. Liu H. Huo L. Dang Y. Wang Y. Yang B. Qiu S. Tan H. Org. Chem. Front. 2018; 5: 1312
- 3g Chatterjee T. Lee DS. Cho EJ. J. Org. Chem. 2017; 82: 4369
- 3h Jin J. MacMillan DW. C. Nature 2015; 525: 87
- 4a Majek M. van Wanglin AJ. Acc. Chem. Res. 2016; 49: 2316
- 4b Yang L. Huang Z. Li G. Zhang W. Cao R. Wang C. Xiao J. Xue D. Angew. Chem. Int. Ed. 2018; 57: 1968
- 4c Natarajan P. Muskan M. Brar NK. Kaur JJ. Org. Chem. Front. 2018; 5: 1527
- 4d Wu Q.-Y. Ao G.-Z. Liu F. Org. Chem. Front. 2018; 5: 2061
- 4e Gualandi A. Rodeghiero G. Della Rocca E. Bertoni F. Marchini M. Perciaccante R. Jansen P. Cerom P. Cozzi PG. Chem. Commun. 2018; DOI: 10.1039/C8CC04048F.
- 4f McManus JB. Onuska NP. R. Nicewicz DA. J. Am. Chem. Soc. 2018; DOI: 10.1021/jacs.8b04890.
- 4g Xie P. Fan J. Liu Y. Wo X. Fu W. Loh T.-P. Org. Lett. 2018; 20: 3341
- 4h Yin Y. Dai Y. Jia H. Li J. Bu L. Qiao B. Zhao X. Jiang Z. J. Am. Chem. Soc. 2018; 140: 6083
- 4i Zhao G. Kaur S. Wang T. Org. Lett. 2017; 19: 3291
- 4j McManus JB. Nicewicz DA. J. Am. Chem. Soc. 2017; 139: 2880
- 4k Jiang J. Zhang W.-M. Dai J.-J. Xu J. Xu H.-J. J. Org. Chem. 2017; 82: 3622
- 4l Margrey KA. McManus JB. Bonazzi S. Zecri F. Nicewicz DA. J. Am. Chem. Soc. 2017; 139: 11288
- 4m Griffin JD. Zeller MA. Nicewicz DA. J. Am. Chem. Soc. 2015; 137: 11340
- 4n Xiao T. Dong X. Tang Y. Zhou L. Adv. Synth. Catal. 2012; 354: 3195
- 5a Pschorr R. Chem. Ber. 1896; 29: 496
- 5b Duclos RI. Jr. Tung JS. Rapoport H. J. Org. Chem. 1984; 49: 5243
- 5c Wassmundt FW. Kiesman WF. J. Org. Chem. 1995; 60: 196
- 5d Zhou J. Huang L.-Z. Li Y.-Q. Du Z.-T. Tetrahedron Lett. 2012; 53: 7036
- 5e Moorthy JN. Samanta S. J. Org. Chem. 2007; 72: 9786
- 6a Chakrabarty I. Akram MO. Biswas S. Patil NT. Chem. Commun. 2018; 54: 7223
- 6b Yao C.-J. Sun Q. Rastogi N. König B. ACS Catal. 2015; 5: 2935
- 6c Shu X.-Z. Zhang M. He Y. Frei H. Toste FD. J. Am. Chem. Soc. 2014; 136: 5844
- 6d Verberne-Sutton SD. Quarels RD. Zhai X. Garno JC. Ragains JR. J. Am. Chem. Soc. 2014; 136: 14438
- 6e Hari DP. Hering T. König B. Org. Lett. 2012; 14: 5334
- 6f Hering T. Hari DP. König B. J. Org. Chem. 2012; 77: 10347
- 6g Hari DP. Schroll P. König B. J. Am. Chem. Soc. 2012; 134: 2958
- 7a Cano-Yelo H. Deronzier A. J. Chem. Soc., Perkin Trans. 2 1984; 1093
- 7b Cano-Yelo H. Deronzier A. J. Photochem. 1987; 37: 315
- 8 For a recent report on photoredox approach to 6H-benzo[c]chromenes, see: Deng Q. Tan L. Xu Y. Liu P. Sun P. J. Org. Chem. 2018; 83: 6151
- 9 Sun C.-L. Gu Y.-F. Huang W.-P. Shi Z.-J. Chem. Commun. 2011; 47: 9813
- 10 Chen D. Pan F. Gao J. Yang J. Synlett 2013; 24: 2085
- 11 Natarajan R. Kumar N. Sharma M. Org. Chem. Front. 2016; 3: 1265
- 12 6H-Benzo[c]chromenes 2a–o: Typical Procedure A 10 mL reaction vial was charged with a magnetic stirrer bar, the appropriate diazonium salt (0.20 mmol), eosin Y (1.3 mg, 1 mol%), and anhyd MeCN (2 mL). The vial was sealed and the mixture was then bubbled with N2 for 10 min. After irradiating with 36 W green LEDs for 16 h, the mixture was purified directly by column chromatography (silica gel).
- 13 2,7-Dimethyl-6H-benzo[c]chromene (2i) White crystalline solid; yield: 26.9 mg (64%; 0.2 mmol scale); mp 72–73 °C. IR (film): 2923, 1501, 1459, 1250, 1028, 816, 736 cm–1. 1H NMR (400 MHz, CDCl3): δ = 7.58 (d, J = 8.0 Hz, 1 H), 7.55 (d, J = 1.6 Hz, 1 H), 7.29 (dd, J = 8.0, 7.6 Hz, 1 H), 7.14 (d, J = 7.6 Hz, 1 H), 7.06 (dd, J = 8.4, 1.6 Hz, 1 H), 6.91 (d, J = 8.0 Hz, 1 H), 5.16 (s, 2 H), 2.39 (s, 3 H), 2.33 (s, 3 H). 13C NMR (100 MHz, CDCl3): δ = 152.3, 133.1, 131.3, 130.2, 130.0, 129.9, 129.4, 127.8, 123.9, 122.8, 119.8, 116.8, 65.6, 20.9, 18.5. GC/MS: m/z (%) = 209 (100) [M – H]+, 210 (72) [M]+. HRMS (CI): m/z [M]+ Calcd for C15H14O: 210.1045; found: 210.1048.
For selected reviews on photoredox catalysis, see:
For selected examples on Ru-catalyzed photoredox catalysis, see:
For selected examples on Ir-catalyzed photoredox catalysis, see:
For selected examples on organic photoredox catalysis, see:
Selected examples for Pschorr reaction, see:
For selected examples of diazonium salts involving photoredox catalysis, see:
Photoredox Pschorr reactions, see: