Supporting information
The synthesis of coumarin derivatives using Choline chloride/zinc
chloride as a deep eutectic solvent
Fariba Keshavarzipour, Hossein Tavakol*
Department of Chemistry, Isfahan University of Technology, Isfahan 84156-83111, Iran.
Fax: +98-31-33913241; E-mail: h_tavakol@cc.iut.ac.ir , hosein_ta@yahoo.com
List of Contents
Experiment Section
S2
Spectroscopic Data of the Catalyst and Product
S3
FT-IR, 1H NMR and 13C NMR Spectra of the Compound
S4-S10
S1
Experimental Section:
General information
All chemical compounds have purchased from Sigma-Aldrich and Merck companies and used
without further purifications. Melting points were determined using Gallen Kamp melting point
apparatus. Thin layer chromatography was used to monitor the reaction and check purities. IR
spectra (KBr) were recorded by JASCO FT-IR and 1HNMR spectra and
13
CNMR spectra were
recorded by Brucker Ultrashield 400 MHz. NMR chemical shifts were expressed in ppm versus
the chemical shift of tetramethylsilane (TMS) as internal reference.
Preparation of Deep Eutectic Solvent
The preparation method involved reaction of ChCl (1 mol) with ZnCl2 (2 mol) at 100 °C to
obtain a clear solution that will be used without further purification.
General procedure for synthesis of coumarin derivatives
In a 50 mL round-bottom flask equipped with condenser arranged on magnetic stirrer, 1mmol of
salicylaldehyde (or its derivatives) and 1mmol of diethylmalonate (or similar structures) was
added to 10 mol% DES to and reaction mixture was stirred at 80°C in oil bath. The reaction was
monitored by TLC to show the completion of reaction. After terminating reaction, 2.5 mL of
water was added and precipitated product was filtered and dried. The product was purified by
crystallization using ethanol. The filtrate, containing catalyst, was recycled directly in next runs
without further purification.
S2
Original spectra and spectroscopic data of the catalyst and products
N
The DES:
OH
Cl2Zn-Cl
Elemental Anal. For the above compound: (C,14.75; H, 3.42; N, 3.4) Found: (C, 14.54; H, 4.037;
N, 3.48).
S3
O
OMe
O
O
methyl 2-oxo-2H-chromene-3-carboxylate (1a)
Elemental Anal. C11H8O4 C, 64.71; H, 3.95; O, 31.34, Found: C, 64.42; H, 3.640; O, 31.331.
S4
CN
O
O
2-oxo-2H-chromene-3-carbonitrile (1b)
1
HNMR (CDCl3); δ (ppm): 7.45(t, 2H), 7.67(d, 1H), 7.77 (t, 1H), 8.32(s, 1H).
13
CNMR
(CDCl3); δ (ppm): 103.77, 113.96, 117.56, 117.89, 129.15, 129.73, 136.00, 152.29, 155.02,
156.88. MS (EI): 171(M+, 100), 143(97), 115(37), 88(21), 63(15).
O
Ph
O
O
S5
3-benzoyl-2H-chromen-2-one (1c)
Yield 95%: yellow Solid. m.p. 148-149oC;
S6
O
C
HO
O
OMe
O
methyl 7-hydroxy-2-oxo-2H-chromene-3-carboxylate (2a)
IR nmax=cm-1: 3550, 3470, 1739, 1617; 1H NMR (300 MHz, DMSOd6) d 3.85 (s, 3H), 6.72 (d,
J¼1.8 Hz, 1H), 6.88 (dd, J¼8.2 and 1672 H.1.8 Hz, 1H), 7.45 (d, J¼8.2 Hz, 1H), 8.67 (s, 1H);
13
C NMR (75MHz, DMSO-d6) d 52 .5, 110.4, 111.5, 112, 132, 132.8, 150, 150.5, 156.7,
163.8, 165.9.
S7
CN
HO
O
O
7-Hydroxy-2-oxo-2H-chromene-3-carbonitrile (2b)
IR (KBr) (mmax/cm-1): 3395 (broad), 2227, 1720, 1638; 1H-NMR (400 MHz, DMSO-d6) d 7.13
(dd, J ¼ 8.85, 2.41 Hz, 1H), 7.15 (d, J ¼ 2.41 Hz, 1H), 7.78 (d, J ¼ 8.85 Hz, 1H), 8.78 (s, 1H),
8.81 (s, 1H, OH); 13C-NMR (100 MHz, DMSO-d6) d 104.25, 114.45, 117.85, 121.12, 128.05,
133.32, 138.68, 154.58, 159.46, 161.09; Anal. Calcd (%) for C10H5NO3: C, 64.18; H, 2.69; N,
7.48. Found (%): C, 64.25; H, 2.71; N, 7.51.
O
Br
OMe
O
O
methyl 6-bromo-2-oxo-2H-chromene-3-carboxylate (3a)
Yield 94%: yellow Solid. m.p. 180-182oC;
S8
Br
CN
O
O
6-Bromo-2-oxo-2H-chromene-3-carbonitrile (3b)
IR (KBr) (mmax/cm-1): 2223, 1732, 1641; 1H-NMR (400 MHz, DMSO-d6) d 7.15 (d, J ¼ 7.36
Hz, 1H), 7.25 (dd, J ¼ 7.36, 1.96 Hz, 1H), 7.41 (d, J ¼ 1.96 Hz, 1H), 8.82 (s, 1H); 13CNMR (100
MHz, DMSO-d6) d 105.52, 114.32, 116.02, 119.98, 128.63, 131.08, 138.78, 152.42, 157.86,
160.32; Anal. Calcd (%) for C10H4BrNO2: C, 48.03; H, 1.61; N, 5.60. Found (%): C, 48.20; H,
1.64; N, 5.65.
S9
O
C
Br
O
Ph
O
3-benzoyl-6-bromo-2H-chromen-2-one (3c)
1H NMR (400 MHz, DMSO-d6-TMS): 8.78 (s, 1H, Ar- H), 8.19 (s, 1H, Ar-H), 7.31-7.88 (m,
7H, Ar-H); 13C NMR (100 MHz, DMSO-d6-TMS): 192.3, 158.3, 152.7, 139.7, 137.4, 134.6,
134.2, 130.0, 129.6, 129.3, 127.0, 126.7, 126.3, 122.4, 119.1, and 118.1.
S10