F
R. Talukdar
Letter
Synlett
2014, 10, 622. (d) Alinezhad, H.; Tavakkoli, S. M.; Salehian, F.
Synth. Commun. 2010, 40, 3226. (e) Wong, S.-T.; Hwang, C.-C.;
Mou, C.-Y. Appl. Catal. B. 2006, 63, 1. (f) Oberhauser, T. J. Org.
Chem. 1997, 62, 4504. (g) Koini, E. N.; Avlonitis, N.;
Calogeropoulou, T. Synlett 2011, 1537. (h) Esumi, T.; Makado,
G.; Zhai, H.; Shimizu, Y.; Mitsumoto, Y.; Fukuyama, Y. Bioorg.
Med. Chem. Lett. 2004, 14, 2621. (i) Greenfield, A. A.; Butera, J.
A.; Caufield, C. E. Tetrahedron Lett. 2003, 44, 2729.
found: 298.9526.
3-Chloropropyl 3-bromo-4-hydroxybenzoate (4f): Yield: 446
mg (76%); Rf 0.35 (EtOAc/petroleum ether, 1:4); white crystal-
line solid; mp 92–94 °C; 1H NMR (400 MHz, CDCl3): = 2.22
(quin, J = 8.0 Hz, 2 H), 3.68 (t, J = 8.0 Hz, 2 H), 4.45 (t, J = 8.0 Hz, 2
H), 6.15 (br s, 1 H), 7.05 (d, J = 8.0 Hz, 1 H), 7.91 (dd, J = 8.0, 4.0
Hz, 1 H), 8.17 (d, J = 4.0 Hz, 1 H); 13C NMR (100 MHz, CDCl3): =
31.8, 41.4, 62.1, 110.3, 116.0, 124.0, 131.2, 134.1, 156.5, 165.1;
HRMS (ESI): m/z [M + Na]+ calcd for C10H10BrClNaO3: 314.9400;
found: 314.9398.
Prop-2-yn-1-yl 3-bromo-4-hydroxybenzoate (4h): Yield: 311
mg (61%); Rf 0.43 (EtOAc/petroleum ether, 1:4); white crystal-
line solid; mp 144–146 °C; 1H NMR (400 MHz, CDCl3): = 2.52
(s, 1 H), 4.90 (d, J = 2.0 Hz, 2 H), 6.01 (br s, 1 H), 7.06 (d, J = 8.0
Hz, 1 H), 7.95 (dd, J = 8.0, 2.0 Hz, 1 H), 8.22 (d, J = 4.0 Hz, 1 H);
13C NMR (100 MHz, CDCl3): = 52.7, 75.3, 77.7, 110.3, 116.0,
123.4, 131.5, 134.3, 156.7, 164.4; HRMS (ESI): m/z [M + H]+
calcd for C10H8BrO3: 254.9657; found: 254.9661.
Cyclohexyl 3-bromo-4-hydroxybenzoate (4j): Yield: 395 mg
(66%); Rf 0.39 (EtOAc/petroleum ether, 1:4); white crystalline
solid; mp 119–121 °C; 1H NMR (400 MHz, CDCl3): = 1.31–1.48
(m, 3 H), 1.53–1.60 (m, 3 H), 1.77–1.79 (m, 2 H), 1.92–1.94 (m, 2
H), 4.99 (quin, J = 4.0 Hz, 1 H), 6.04 (bs, 1H), 7.04 (d, J = 8.0 Hz, 1
H), 7.93 (d, J = 12.0 Hz, 1 H), 8.18 (s, 1 H); 13C NMR (100 MHz,
CDCl3): = 23.9, 25.6, 31.8, 73.5, 110.1, 115.8, 125.0, 131.1,
134.0, 156.2, 164.7; HRMS (ESI): m/z [M + Na]+ calcd for
(5) For the photocatalytic syntheses of aldehyde to ester, see:
(a) Pandey, G.; Koley, S.; Talukdar, R.; Sahani, P. K. Org. Lett.
2018, 20, 5861; and references cited therein. (b) Pinnick, H. W.;
Lajis, N. H. J. Org. Chem. 1978, 43, 371. (c) Guo, Z.; Xin, H.; Ma, J.;
Bai, M.; Wang, Y.; Li, J. Catalysts 2017, 7, 276. (d) Verma, S.; Baig,
R. B. N.; Nadagouda, M. N.; Varma, R. S. Catal. Today 2018, 309,
248. (e) Zhang, Y.; Xiao, Q.; Bao, Y.; Zhang, Y.; Bottle, S.; Sarina,
S.; Zhaorigetu, B.; Zhu, H. J. Phys. Chem. C 2014, 118, 19062.
(f) Verma, S.; Baig, R. B. N.; Han, C.; Nadagouda, M. N.; Varma, R.
S. Green Chem. 2016, 18, 251. (g) Manríquez, M. E.; Morales-
Mendoza, G.; Alamilla, J.; Trejo, U.; Gómez, R.; Ortiz-Islas, E.
Reac. Kinet. Mech. Cat. 2017, 122, 1281. (h) Chen, Y.; Ji, X.; Paul,
B.; Vadivel, S. Mater. Lett. 2019, 237, 113. (i) Song, L.; Zhang, S.;
Wu, X.; Tian, H.; Wei, Q. Ind. Eng. Chem. Res. 2012, 51, 9510.
(j) März, M.; Chudoba, J.; Kohouta, M.; Cibulka, R. Org. Biomol.
Chem. 2017, 15, 1970.
(6) (a) Liu, M.; Wang, G.; Xiao, L.; Xu, X.; Liu, X. Xu P., Lin X. 2014, 12,
3838. (b) Zhao, J.; Fan, X.; Wang, S.; Li, S.; Shang, S.; Yang, Y.; Xu,
N.; Lü, Y.; Shi, J. J. Nat. Prod. 2004, 67, 1032. (c) Wang, L.-J.; Guo,
C.-L.; Li, X.-Q.; Wang, S.-Y.; Jiang, B.; Zhao, Y.; Luo, J.; Xu, K.; Liu,
H.; Guo, S.-J.; Wu, N.; Shi, D.-Y. Mar. Drugs 2017, 15, 343.
(7) Synthetic Route to 3-Bromo-4-hydroxy Butyl Benzoate (4a);
Typical Procedure
C
13H15BrNaO3: 321.0102; found: 321.0101.
Undecyl 3-bromo-4-hydroxybenzoate (4l): Yield: 379 mg
(51%); Rf 0.58 (EtOAc/petroleum ether, 1:4); white crystalline
solid; mp 59–61 °C; 1H NMR (400 MHz, CDCl3): = 0.87 (t, J =
8.0 Hz, 3 H), 1.26–1.41 (m, 15 H), 1.70–1.78 (m, 3 H), 4.28 (t, J =
8.0 Hz, 2 H), 6.22 (br s, 1 H), 7.04 (d, J = 8.0 Hz, 1 H), 7.91 (dd, J =
8.0, 2.0 Hz, 1 H), 8.18 (d, J = 4.0 Hz, 1 H); 13C NMR (100 MHz,
CDCl3): = 14.3, 22.8, 26.1, 28.8, 29.4, 29.5, 29.6, 29.7 (2), 32.0,
65.5, 110.2, 115.9, 124.5, 131.1, 134.1, 156.4, 165.4; HRMS
(ESI): m/z [M + Na]+ calcd for C18H27BrNaO3: 393.1041; found:
393.1044.
A 10 mL double-necked round-bottomed flask equipped with a
magnetic stirring bar was charged with 4-hydroxybenzalde-
hyde
(1)
(244
mg,
2.0
mmol),
photocatalyst
IrIII[df(CF3)ppy]2(dtbbpy)PF6 (45 mg, 0.04 mmol), CCl3Br [2, 793
mg, 4.0 mmol (to synthesize 4a'–l', 4.0 mmol of Selectfluor 12
was used instead, with 2.0 mmol of 1 or non-hydroxy benzalde-
hydes 13a–c and the inert atmosphere was maintained)], n-
BuOTBDMS (3a) (1.13 g, 6.0 mmol) and acetonitrile (5.0 mL) at
room temperature. The mixture was irradiated under 445 nm
blue LED array for 7 h in air. The reaction was monitored by TLC.
After completion of the reaction the solvent was evaporated
under reduced pressure. The residue was distributed in water
(10 mL) and extracted with ethyl acetate (20×3 mL). The com-
bined organic layers were dried with anhydrous MgSO4 and
concentrated under reduced pressure. The crude product was
purified by column chromatography by using 100–200 mesh
silica gel with use of 5–10% ethyl acetate in hexanes as the
eluent to afford pure 3-bromo-4-hydroxy butyl benzoate (4a) as
a white crystalline solid in 85% yield (464 mg). A similar meth-
odology was executed with the other substrates.
(8) (a) Caldwell, N.; Jamieson, C.; Simpson, I.; Watson, A. J. B. Chem.
Commun. 2015, 51, 9495. (b) Queyroy, S.; Vanthuyne, N.;
Gastaldi, S.; Bertrand, M. P.; Gil, G. Adv. Synth. Catal. 2012, 354,
1759. (c) McAllister, L. A.; Bechle, B. M.; Dounay, A. B.; Evrard,
E.; Gan, X.; Ghosh, S.; Kim, J.-Y.; Parikh, V. D.; Tuttle, J. B.;
Verhoest, P. R. J. Org. Chem. 2011, 76, 3484. (d) Nechab, M.; Blidi,
L. E.; Vanthuyne, N.; Gastaldi, S.; Bertrand, M. P.; Gil, G. Org.
Biomol. Chem. 2008, 6, 3917.
(9) Zhang, P.; Le, C.; MacMillan, D. W. C. J. Am. Chem. Soc. 2016, 138,
8084.
(10) (a) Kharasch, M. S.; Jensen, E. V.; Urry, W. H. Science 1945, 102,
128. (b) Kharasch, M. S.; Jensen, E. V.; Urry, W. H. J. Am. Chem.
Soc. 1947, 69, 1100. (c) Kharasch, M. S.; Kuderna, B. M.; Urry, W.
J. Org. Chem. 1948, 13, 895.
Spectral Data of New Compounds
(11) (a) Lantaño, B.; Postigo, A. Org. Biomol. Chem. 2017, 15, 9954.
(b) Bloom, S.; McCann, M.; Lectka, T. Org. Lett. 2014, 16, 6338.
(c) Ventre, S.; Petronijevi, F. R.; MacMillan, D. W. C. J. Am. Chem.
Soc. 2015, 137, 5654. (d) Nyffeler, P. T.; Durón, S. G.; Burkart, M.
D.; Vincent, S. P.; Wong, C.-H. Angew. Chem. Int. Ed. 2005, 44,
192. (e) Kee, C. W.; Chin, K. F.; Wong, M. W.; Tan, C.-H. Chem.
Commun. 2014, 50, 8211. (f) Wu, X.; Meng, C.; Yuan, X.; Jia, X.;
Qian, X.; Ye, J. Chem. Commun. 2015, 51, 11864.
2,2,2-Trifluoroethyl 3-bromo-4-hydroxybenzoate (4d): Yield:
465 mg (78%); Rf 0.39 (EtOAc/petroleum ether, 1:4); white crys-
talline solid; mp 53–55 °C; 1H NMR (400 MHz, CDCl3): = 4.68
(q, JH–F = 8.0 Hz, 2 H), 6.14 (br s, 1 H), 7.08 (d, J = 8.0 Hz, 1 H),
7.96 (dd, J = 8.0, 4.0 Hz, 1 H), 8.21 (d, J = 2.0 Hz, 1 H); 13C NMR
(100 MHz, CDCl3): = 61.0 (q, JC–F = 36.3 Hz), 110.5, 116.2,
122.3, 123.2 (q, JC–F = 275.7 Hz), 131.7, 134.5, 157.2, 163.6;
HRMS (ESI): m/z [M + H]+ calcd for C9H7BrF3O3: 298.9531;
© 2019. Thieme. All rights reserved. — Synlett 2019, 30, A–F