Synlett 2018; 29(05): 609-612
DOI: 10.1055/s-0036-1591739
letter
© Georg Thieme Verlag Stuttgart · New York

A Combined Tamaru Allylation/Olefin Cross-Metathesis Approach for the Total Syntheses of (±)-Paniculidine B, (±)-Paniculidine C, and 2-Methylcarbazole

Yi-Lun Tseng
a   Department of Applied Chemistry, National Chiao Tung University, 1001 University Road, Hsinchu 30010, Taiwan
,
Min-Chieh Liang
a   Department of Applied Chemistry, National Chiao Tung University, 1001 University Road, Hsinchu 30010, Taiwan
,
I-Chia Chen
b   Department of Cosmetic Applications and Management, Cardinal Tien Junior College of Healthcare and Management, New Taipei City 23143, Taiwan   eMail: yenkuwu@nctu.edu.tw
,
Yen-Ku Wu  *
a   Department of Applied Chemistry, National Chiao Tung University, 1001 University Road, Hsinchu 30010, Taiwan
› Institutsangaben
We thank the Ministry of Science and Technology, Taiwan for financial support of this work (Grant Nos. 104-2113-M-009-022-MY2 and 106-2113-M-009-011-MY2).
Weitere Informationen

Publikationsverlauf

Received: 07. Oktober 2017

Accepted after revision: 18. November 2017

Publikationsdatum:
20. Dezember 2017 (online)


Abstract

A concise approach to the total syntheses of racemic paniculidines B and C is described. The route features a combined Tamaru allylation/olefin cross-metathesis sequence for the regiocontrolled synthesis of prenylindole intermediates. In addition, we report a transformation of the prenylated indole into 2-methylcarbazole catalyzed by sulfonic acid-functionalized silica gel.

Supporting Information

 
  • References and Notes

    • 1a Sayar K. Paydar M. Pingguan-Murphy B. Med. Aromat. Plants 2014; 3: 173
    • 1b Ng MK. Abdulhadi-Noaman Y. Cheah YK. Yeap SK. Alitheen NB. Int. Food Res. J. 2012; 19: 1306
  • 2 Kinoshita T. Tatara S. Sankawa U. Chem. Pharm. Bull. 1985; 33: 1770
  • 3 Ito C. Furukawa H. Ishii H. Ishikawa T. Haginiwa J. J. Chem. Soc., Perkin Trans. 1 1990; 7: 2047
  • 4 Kong Y.-C. Cheng K.-F. Cambie RC. Waterman PG. J. Chem. Soc., Chem. Commun. 1985; 47
  • 5 Kinoshita T. Tatara S. Ho F.-C. Sankawa U. Phytochemistry 1989; 28: 147
    • 6a Chakraborty DP. In The Alkaloids: Chemistry and Pharmacology . Vol. 44. Cordell GA. Academic Press; San Diego: 1993: 257
    • 6b Kumar V. Wickramaratne DB. M. Jacobsson U. Tetra­hedron Lett. 1990; 31: 5217

    • For a comprehensive review on carbazole alkaloids, see:
    • 6c Schmidt AW. Reddy KR. Knölker H.-J. Chem. Rev. 2012; 112: 3193
  • 7 Jeffery T. J. Chem. Soc., Chem. Commun. 1984; 1287
  • 8 Somei M. Ohnishi H. Chem. Pharm. Bull. 1985; 33: 5147
  • 9 At the time, the isolation of paniculidine C had not been disclosed; See Ref. 2.
  • 10 Selvakumar N. Rajulu GG. J. Org. Chem. 2004; 69: 4429
  • 11 Cheskis BA. Alekseev IG. Moiseenkov AM. Zh. Org. Khim. 1990; 26: 425
  • 13 For a leading review, see: Lindel T. Marsch N. Adla SK. Top. Curr. Chem. 2012; 309: 67

    • For leading examples, see:
    • 14a Casanati G. Francioni M. Guareschi A. Pochini A. Tetrahedron Lett. 1969; 10: 2485
    • 14b Bocchi V. Casanati G. Marchelli R. Tetrahedron 1978; 34: 929
    • 14c Wenkert E. Angell EC. Ferreira VF. Michelotti EL. Piettre SR. Sheu J.-H. Swindell CS. J. Org. Chem. 1986; 51: 2343
    • 14d Zhu X. Ganesan A. J. Org. Chem. 2002; 67: 2705
    • 14e Müller JM. Stark CB. W. Angew. Chem. Int. Ed. 2016; 55: 4798
    • 14f Trost BM. Chan WH. Malhotra S. Chem. Eur. J. 2017; 23: 4405
    • 14g Tanaka S. Shiomi S. Ishikawa H. J. Nat. Prod. 2017; 80: 2371 ; and references cited therein

      For conceptually relevant examples, see:
    • 15a Austin JF. Kim S.-G. Sinz CJ. Xiao W.-J. MacMillan DW. C. Proc. Natl. Acad. Sci. U. S. A. 2004; 101: 5482
    • 15b Spessard SJ. Stoltz BM. Org. Lett. 2002; 4: 1943
    • 15c De S. Rigby JH. Tetrahedron Lett. 2013; 54: 4760
  • 16 Kimura M. Futamata M. Mukai R. Tamaru Y. J. Am. Chem. Soc. 2005; 127: 4592
    • 17a Kawasaki T. Tabata M. Nakagawa K. Kobayashi K. Kodama A. Kobayashi T. Hasegawa M. Tanii K. Somei M. Heterocycles 2015; 90: 1038
    • 17b Kawasaki T. Kodama A. Nishida T. Shimizu K. Somei M. Heterocycles 1991; 32: 221
  • 18 Chatterjee AK. Choi T.-L. Sanders DP. Grubbs RH. J. Am. Chem. Soc. 2003; 125: 11360
  • 19 When the hydrogenation reaction was carried out in either MeOH or a mixture of EtOAc and hexanes, the formation of paniculidine C (2) in various amounts could not be circumvented.
  • 20 Paniculidine B (1) A mixture of compound 5 (46 mg, 0.2 mmol) and 20 mass% Pd/C (9 mg) was stirred in THF (4 mL) under H2 (balloon) at r.t. for 6 h. The mixture was filtered through a short pad of Celite, which was washed with THF (2 × 5 mL). To the stirred filtrate was added NaBH4 (8 mg, 0.2 mmol) at r.t. After 3 h, the reaction was quenched with sat. aq NH4Cl (10 mL), and the mixture was extracted with Et2O (3 × 10 mL). The combined organic layers were washed with brine (10 mL), dried (MgSO4), filtered, and concentrated under reduced pressure. The residue was purified by flash chromatography [silica gel, MeOH–CH2Cl2 (1:80)] to give a colorless oil; yield: 42 mg (90%). Note: NaBH4 was added in this step to reduce a minor amount of aldehyde in the crude mixture, presumably generated via alkene isomerization of 5 under the hydrogenation conditions. IR (CHCl3): 3688, 1603, 1460 cm–1. 1H NMR (400 MHz, CDCl3): δ = 7.58 (ddd, J = 7.9, 1.0, 1.0 Hz, 1 H), 7.41 (ddd, J = 8.2, 0.9, 0.9 Hz, 1 H), 7.24 (ddd, J = 8.1, 7.1, 1.1 Hz, 1 H), 7.11 (ddd, J = 8.0, 7.1, 1.0 Hz, 1 H), 7.06 (d, J = 1.0 Hz, 1 H), 4.05 (s, 3 H), 3.57 (dd, J = 10.4, 5.8 Hz, 1 H), 3.50 (dd, J = 10.0, 6.3 Hz, 1 H), 2.82 (dddd, J = 14.7, 10.0, 5.6, 1.0 Hz, 1 H), 2.72 (dddd, J = 14.7, 9.8, 6.3, 0.9 Hz, 1 H), 1.91–1.83 (m, 1 H), 1.79–1.70 (m, 1 H), 1.53 (dddd, J = 13.4, 9.8, 8.0, 5.6 Hz, 1 H), 1.40 (br s, 1 H), 1.03 (d, J = 6.7 Hz, 3 H). 13C NMR (100 MHz, CDCl3): δ = 132.79, 123.96, 122.31, 120.43, 119.37, 119.13, 112.96, 108.32, 68.21, 65.44, 35.50, 33.41, 22.43, 16.53. HRMS (EI): m/z [M+] calcd for C14H19NO2: 233.1416; found: 233.1410.
    • 21a Cheng K.-F. Kong Y.-C. Chan T.-Y. J. Chem. Soc., Chem. Commun. 1985; 48
    • 21b Wenkert E. Moeller PD. R. Piettre SR. McPhail AT. J. Org. Chem. 1988; 53: 3170
    • 21c Sheu J.-H. Chen Y.-K. Hong Y.-LV. Tetrahedron Lett. 1991; 32: 1045
    • 21d Sheu J.-H. Chen C.-A. Chen B.-H. Chem. Commun. 1999; 203
    • 21e Abe T. Komatsu H. Ikeda T. Hatae N. Toyota E. Ishikura M. Heterocycles 2012; 86: 505
  • 22 Sheu J.-H. Chen Y.-K. Hong Y.-LV. J. Org. Chem. 1993; 58: 5784
  • 23 For the purpose of comparison, we adopted Sheu’s conditions that effected the transformation of 3-(1-hydroxy-3-methylbut-3-enyl)indole into yuehchukene (Table 1, entry 1); see Ref. 22.
  • 24 For the isolation of 4 from natural sources, see: Kruber O. Marx A. Chem. Ber. 1938; 71: 2478
  • 25 Lu and co-workers have reported the palladium-catalyzed synthesis of 2-methylcarbazole (4) from 3-(3-methyl-3-butenyl)indole in 40% yield; see: Kong A. Han X. Lu X. Org. Lett. 2006; 8: 1339
  • 26 Wilsdorf M. Leichnitz D. Reissig H.-U. Org. Lett. 2013; 15: 2494

    • β-Hydroxysulfonic acid-functionalized silica gel (HO-SAS; Chromatorex-DPR, 0.5 mmol/g of SO3H) has been commercially developed by Fuji Silysia Chemical Ltd. For applications of HO-SAS as a catalyst in organic synthesis, see:
    • 27a Furuta A. Fukuyama T. Ryu I. Bull. Chem. Soc. Jpn. 2017; 90: 607
    • 27b Furuta A. Hirobe Y. Fukuyama T. Ryu I. Manabe Y. Fukase K. Eur. J. Org. Chem. 2017; 1365
    • 27c Fujii H. Yamada T. Hayashida K. Kuwada M. Hamasaki A. Nobuhara K. Ozeki S. Nagase H. Heterocycles 2012; 85: 2685
  • 28 For a Brønsted acid-catalyzed synthesis of functionalized carbazoles from 2-substituted indoles, see: Li Q. Peng X.-S. Wong HN. C. Org. Chem. Front. 2014; 1: 1197
  • 29 Zhao J. Li P. Xia C. Li F. Chem. Eur. J. 2015; 21: 16383
  • 30 Chakraborty DP. J. Indian Chem. Soc. 1989; 66: 843