Tetrahedron Letters
Erratum
Erratum to ‘‘Ionic liquids as phase transfer catalysts: Enhancing the
biphasic extractive epoxidation reaction for the selective synthesis
of b-O-glycosides” [Tetrahedron Lett. 58 (2017) 3739–3742]
⇑
Cintia C. Santiago, Leticia Lafuente, Rodolfo Bravo, Gisela Díaz, Agustín Ponzinibbio
Laboratorio de Estudio de Compuestos Orgánicos (LADECOR), Departamento de Química, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 y 115,
1900 La Plata, Argentina
The publisher regrets that references 15, 16, 18 and 19 con-
tained errors. The correct references are as follows:
NMR (300 MHz, CCl3D): d 7.38–7.15 (m, 15H, 3 C6H5), 4.94–
4.81 y 4.64–4.52 (m, 6H, CH2Ph), 4.19 y 4.16 (d, 1H,
J = 7.26 Hz, H-1), 3.74 (m, 2H, H-6), 3.60–3.58 (m, 3H, H-3,
H-4, H-5), 3.55 (s, 3H, OCH3), 3.53 (broad s, 1H, H-2), 2.46
(broad s, 1H, OH). 13C NMR (75 MHz, CCl3D): d 138.65,
138.16, 138.11, 128.56–128.27, 127.99–127.61 (3 C6H5),
103.74 (C1), 84.54 (C3), 77.68 (C4), 75.22 (C10), 75.17 (C9),
75.03 (C8), 74.66 (C2), 73.56 (C5), 68.90 (C6); 57.17 (C22).
15. 1-Dodecyl-3-methylimidazolium tetrafluoroborate. Anhydrous
sodium tetrafluoroborate (15.30 g, 0.14 mol), 1-methylimi-
dazole
(11.5 ml,
0.14 mol)
and
1-bromododecane
(33.55 ml, 0.14 mol) were placed in a round bottom flask
equipped with a reflux condenser. The mixture was stirred
at 80 °C for 4 h, under inert atmosphere. The resultant sus-
pension was diluted with 25.0 ml of acetonitrile and then fil-
tered. After the solvent was removed under reduce pressure,
the ionic liquid was dried at 80 °C in vacuo (0,02 torr) for 6 h
to obtained a light yellow semi-solid product (yield = 97%).
1H NMR (500 MHz, CDCl3): d 8.97 (s, 1H, H-2), 7.42 (s, 1H,
H-4), 7.34 (s, 1H, H-3), 4.14 (t, J = 7.78 Hz, 2 H, H-5), 3.91
(s, 3H, H-1), 1.81 (broad t, 2H, H-6), 1.25–1.18 (m, 18H,
H7-15), 0.81 (t, J = 7.28 Hz, 3H, H-16). 13C NMR (125 MHz,
CDCl3): d 136.20 (C2), 123.79 (C3), 122.13 (C4), 49.96 (C5),
36.22 (C1), 31.83 (C6), 30.07, 29.55, 29.53, 29.47, 29.34,
29.26, 28.93, 26.16, 22.60 (C7–C15), 14.04 (C16).
18. Ionic liquid (10% mmol) and 3,4,6-tri-O-benzyl-D-glucal
(200 mg, 0.48 mmol) were placed in a round-bottomed flask
and dissolved in 2.0 ml of dichloromethane, then were
added acetone (0.8 ml) and saturated NaHCO3 aqueous solu-
tion (1.5 ml). To this vigorously stirred biphasic mixture was
added dropwise a solution of oxone (600 mg, 0.9760 mmol
in 2.5 ml of water) at 0 °C for 15 min, maintaining this tem-
perature 20 min more. The reaction was controlled by TLC,
until no further progress was observed. The mixture was
extracted with dichloromethane (5 Â 2.0 ml) and the com-
bined organic phases were dried over sodium sulphate (Na2-
SO4). This solution was concentrated under reduced pressure
and the residue was purified by column chromatography. 1H
NMR (500 MHz, CCl3D): d 7.43–7.27 (m, 15H, 3 C6H5), 5.43
(d, 1H, J = 3.16 Hz, H-1), 4.92–4.73 (m, 1H, H-2), 4.66–4.43
(m, 6H, CH2Ph), 4.30 (d, 1H, J = 7.55 Hz, H-C5), 4.01 (d, 1H,
H-4), 3.59–3.47 (m, 2H, H-C6), 1.86 and 1.38 (m, 2H, OH
C2 and C3). 13C NMR (125 MHz, CCl3D): d 138.15–136.01,
128.50–127.94 (C6H5), 93.38 (C1), 82.73 (C4), 78.39 (C3),
75.22 (C2), 74.87–73.58 (CH2Ph), 73.23 (C5), 69.21 (C6).
Minor b anomer: d 4.82 and 97.39 (H-1 and C1).
16. Ionic liquid (10% mmol) and 3,4,6-tri-O-benzyl-D-glucal
(200 mg, 0.48 mmol) were placed in a round-bottomed flask
and dissolved in 2.0 ml of dichloromethane, then were added
acetone (0.8 ml) and saturated NaHCO3 aqueous solution
(1.5 ml). To this vigorously stirred biphasic mixture was
added dropwise a solution of oxone (600 mg, 0.9760 mmol
in 2.5 ml of water) at 0 °C for 15 min, maintaining the temper-
ature 20 min more. After completion of the reaction, the mix-
ture was extracted with dichloromethane (5 Â 2.0 ml) and
the combined organic phases were dried over sodium sul-
phate (Na2SO4). After filtration, the solvent was evaporated
and the residue was immediately dissolved in anhydrous
methanol (5.0 ml) and stirred for 12 h at room temperature.
This solution was concentrated under reduced pressure and
the residue was purified by column chromatography to obtain
19. 1H NMR (600 MHz, CCl3D): d 7.42–7.18 (m, 15H, 3 C6H5), 5.00
(d, 1H, 11.37 Hz, H-5), 4.88–4.53 (m, 6H, CH2Ph), 3.90 (d, 1H,
J = 8.83 Hz, H-1), 3.73–3.71 (dd, 1H, H-6), 3.66–3.53 (m, 5H,
H-3, H-4, H-6 and CH2OH), 3.38–3.35 (t, 1H, 8.91 Hz, H-2),
3.03–3.00 (m, 2H, CH2N). 13C NMR (150 MHz, CCl3D): d
138.71, 138.08, 137.86, 128.61–127.72 (C6H5), 90.91 (C1),
85.54 (C3), 77.67 (C4), 75.87 (C5), 75.09 (C2), 75.02, 74.58,
73.52 (CH2Ph), 68.98 (C6), 62.99 (CH2OH), 49.48 (NCH2).
pure methyl 3,4,6-tri-O-benzyl-b-D
-glucopyranoside. 1H
Corresponding author.
The publisher would like to apologise for any inconvenience
caused.
⇑
0040-4039/Ó 2017 Elsevier Ltd. All rights reserved.
Santiago, Cintia C.
