Synlett
DOI: 10.1055/s-0041-1738436
cluster
Natural Product Synthesis

Synthetic Studies Toward Daphnezomines A and B

Chenguang Dou
,
Ming Yang
Financial Support was provided by Lanzhou University, National Natural Science Foundation of China (21901094 and 22071089).


Abstract

Synthetic studies toward daphnezomines A and B, members of Daphniphyllum alkaloid group with a rare azaadamantane core structure, are reported. The tricyclic carbon skeleton with two contiguous quaternary carbon centers was synthesized in nine steps from (R)-piperitone. An intramolecular Tsuji–Trost reaction was used as a key reaction for the assembly of the skeleton.

Supporting Information



Publikationsverlauf

Eingereicht: 26. Februar 2023

Angenommen nach Revision: 21. März 2023

Artikel online veröffentlicht:
04. Mai 2023

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  • References and Notes

  • 4 Weiss ME, Carreira EM. Angew. Chem. Int. Ed. 2011; 50: 11501
  • 7 Yamada R, Adachi Y, Yokoshima S, Fukuyama T. Angew. Chem. Int. Ed. 2016; 55: 6067
  • 8 Chattopadhyay AK, Ly VL, Jakkepally S, Berger G, Hanessian S. Angew. Chem. Int. Ed. 2016; 55: 2577
  • 9 Shi H, Michaelides IN, Darses B, Jakubec P, Nguyen QN. N, Paton RS, Dixon DJ. J. Am. Chem. Soc. 2017; 139: 17755
  • 10 Chen X, Zhang H.-J, Yang X, Lv H, Shao X, Tao C, Wang H, Cheng B, Li Y, Guo J, Zhang J, Zhai H. Angew. Chem. Int. Ed. 2018; 57: 947
  • 13 Zhong J, Chen K, Qiu Y, He H, Gao S. Org. Lett. 2019; 21: 3741
  • 15 Xu G, Wu J, Li L, Lu Y, Li C. J. Am. Chem. Soc. 2020; 142: 15240
  • 16 Cao M.-Y, Ma B.-J, Gu Q.-X, Fu B, Lu H.-H. J. Am. Chem. Soc. 2022; 144: 5750
  • 17 Li L.-X, Min L, Yao T.-B, Ji S.-X, Qiao C, Tian P.-L, Sun J, Li C.-C. J. Am. Chem. Soc. 2022; 144: 18823
  • 18 Morita H, Yoshida N, Kobayashi J. J. Org. Chem. 1999; 64: 7208
  • 19 Zhang Y, Di Y.-T, Mu S.-Z, Li C.-S, Zhang Q, Tan C.-J, Zhang Z, Fang X, Hao X.-J. J. Nat. Prod. 2001; 72: 1325
  • 20 Trost BM, Van Vranken DL. Chem. Rev. 1996; 96: 395
  • 21 Kamatani A, Overman LE. Org. Lett. 2001; 3: 1229
  • 22 Moreno-Dorado FJ, Guerra FM, Manzano FL, Aladro FJ, Jorge ZD, Massanet GM. Tetrahedron Lett. 2003; 44: 6691
  • 23 Grieco PA, Wang C.-LJ, Majetich G. J. Org. Chem. 1976; 41: 726
  • 24 Bian M, Wang Z, Xiong X, Sun Y, Matera C, Nicolaou KC, Li A. J. Am. Chem. Soc. 2012; 134: 8078
  • 25 Aldehyde 14 K2CO3 (6.3 mg, 0.0458 mmol, 1.5 equiv) and Pd(PPh3)4 (3.5 mg, 0.00305 mmol, 0.1 equiv) were sequentially added to a solution of enol 13 (11.0 mg, 0.0305 mmol, 1.0 equiv) in DMSO (0.3 mL) at 23 °C. The resultant mixture was heated to 60 °C and stirred at 60 °C for 3 h, then cooled to 23 °C. The reaction was quenched with sat. aq NaHCO3 (1 mL), and the mixture was extracted with EtOAc (3 × 3 mL). The combined organic phases were washed with brine (1 mL), dried (MgSO4), filtered, and concentrated. The residue was purified by flash column chromatography [silica gel, EtOAc–PE (1:100 → 1:60)] to give a white solid; yield: 6.2 mg (68%); Rf = 0.75 (silica gel, EtOAc–PE, 1:20); [α]D 11.5 +8.5 (c = 0.5, CHCl3). IR (film): 2930, 2872, 1723, 1692, 1385, 1197, 1128, 1091 cm–1. 1H NMR (400 MHz, CDCl3): δ = 9.98 (d, J = 1.3 Hz, 1 H), 5.57 (dd, J = 5.0, 2.4 Hz, 1 H), 4.81 (d, J = 2.2 Hz, 1 H), 4.66 (d, J = 1.9 Hz, 1 H), 3.34 (d, J = 15.5 Hz, 1 H), 3.13 (s, 1 H), 2.93 (d, J = 15.9 Hz, 1 H), 2.69 (td, J = 13.8, 4.5 Hz, 1 H), 2.49–2.39 (m, 1 H), 2.30–2.19 (m, 1 H), 2.11–2.02 (m, 1 H), 2.01–1.85 (m, 2 H), 1.82–1.70 (m, 1 H), 1.70–1.63 (m, 1 H), 1.50–1.41 (m, 1 H), 1.41–1.32 (m, 1 H), 1.32–1.24 (m, 2 H), 1.12 (s, 3 H), 0.97 (d, J = 6.8 Hz, 3 H), 0.92 (d, J = 6.8 Hz, 3 H). 13C NMR (101 MHz, CDCl3): δ = 212.24, 203.79, 149.74, 133.92, 121.95, 108.52, 68.19, 51.11, 46.88, 40.59, 39.93, 33.60, 26.07, 25.04, 24.69, 24.30, 22.33, 21.33, 21.16, 18.51. HRMS (ESI): m/z [M + H]+ calcd for C20H29O2: 301.2162; found: 301.2159.
  • 26 CCDC 2243631 contains the supplementary crystallographic data for compound 14. The data can be obtained free of charge from The Cambridge Crystallographic Data Centre via www.ccdc.cam.ac.uk/structures