306 JOURNAL OF CHEMICAL RESEARCH 2012
Prop-2-ynyl 2-iodobenzoate ester (9): Oil, IR (KBr): νmax = 3294,
2129, 1732, 1246, 1096, 740 cm−1; 1H NMR (400 MHz, CDCl3) δ 7.98
(d, J = 7.9 Hz, 1H), 7.84 (dd, J = 7.8, 1.4 Hz, 1H), 7.40 (dd, J = 11.1,
4.1 Hz, 1H), 7.15 (td, J = 7.9, 1.5 Hz, 1H), 4.93 (d, J = 2.4 Hz, 2H),
2.56 (t, J = 2.4 Hz, 1H); 13C NMR (100 MHz, CDCl3) δ 165.44,
141.51, 133.99, 133.06, 131.29, 127.98, 94.41, 77.34, 75.54 52.98.
HRMS (ESI) Calcd for [C10H7IO2+Na]+: 308.9388. Found: 308.9385.
Ethoxycarbonylmethyl 2-iodobenzoate ester (10): Oil,30 IR (KBr):
νmax = 2963, 1739, 1211, 1013, 744 cm−1; 1H NMR (400 MHz, CDCl3)
δ 7.97 (d, J = 7.9 Hz, 1H), 7.91 (dd, J = 7.7, 1.1 Hz, 1H), 7.38 (t,
J = 7.6 Hz, 1H), 7.14 (td, J = 7.8, 1.3 Hz, 1H), 4.82 (s, 2H),4.23 (q,
J = 7.1 Hz, 2H), 1.27 (t, J = 7.1 Hz, 3H); 13C NMR (100 MHz, CDCl3)
δ 167.45, 165.58, 141.48, 133.81, 133.15, 131.53, 127.99, 94.45,
61.57, 61.47, 14.17).
2.25 (p, J = 6.2 Hz, 2H); 13C NMR (100 MHz, CDCl3) δ 166.43,
141.31, 132.68, 130.92, 127.94, 93.88, 62.42, 41.31, 31.57. HRMS
(ESI) Calcd for [C10H10ClIO2+Na]+: 346.9312. Found: 346.9316.
3-Bromopropyl 2-iodobenzoate (18): Oil, IR (KBr): νmax = 2961,
1
1730, 1289, 1130, 743 cm−1; H NMR (400 MHz, CDCl3) δ 7.98 (d,
J = 7.9 Hz, 1H), 7.77 (d, J = 7.7 Hz, 1H), 7.40 (t, J = 7.6 Hz, 1H),
7.15 (t, J = 7.6 Hz, 1H), 4.48 (t, J = 5.8 Hz, 2H), 3.57 (t, J = 6.3 Hz,
2H), 2.37–2.28 (m, 2H); 13C NMR (100 MHz, CDCl3) δ 166.41,
141.31, 135.21, 132.74, 130.96, 127.97, 93.96, 63.41, 31.64, 29.58.
HRMS (ESI) Calcd for [C10H1079BrIO2+Na]+: 390.8807. Found:
390.8799.
Propane-1,3-diyl bis(2-iodobenzoate) (17): Oil,6 IR (KBr): νmax
=
2963, 1731, 1291, 1132, 743 cm−1; 1H NMR (400 MHz, CDCl3) δ 7.94
(d, J = 7.9 Hz, 2H),7.76 (d, J = 7.6 Hz, 2H), 7.34 (t, J = 7.6 Hz,
2H),7.11 (t, J = 7.3 Hz, 2H), 4.51 (t, J = 6.1 Hz, 4H),2.26 (p, J =
6.1 Hz, 2H); 13C NMR (100 MHz, CDCl3) δ 166.43, 141.29, 135.09,
132.73, 131.00, 127.97, 94.10, 62.46, 27.93.
1-Ethoxycarbonyl-ethyl 2-iodobenzoate ester, (11): Solid, m.p.
1
42–44 °C, IR (KBr): νmax = 2966, 1735, 1250, 1100, 744 cm−1. H
NMR (400 MHz, CDCl3) δ 7.99 (d, J = 7.9 Hz, 1H), 7.92 (dd, J = 7.8,
1.2 Hz, 1H), 7.42 (t, J = 7.6 Hz, 1H), 7.17 (td, J = 7.8, 1.5 Hz, 1H),
5.34 (q, J = 7.1 Hz, 1H), 4.24 (q, J = 7.1 Hz, 2H), 1.63 (d, J = 7.1 Hz,
3H), 1.30 (t, J = 7.1 Hz, 3H).13C NMR (100 MHz, CDCl3) δ 170.44,
165.73, 141.36, 134.30, 132.94, 131.40, 127.95, 94.22, 69.74, 61.52,
16.96, 14.15. HRMS (ESI) Calcd for [C12H13IO4+Na]+: 370.9756.
Found: 370.9755.
4-Chlorobutyl 2-iodobenzoate (19): Oil, IR (KBr): νmax = 2957,
1
1725, 1251, 743 cm−1; H NMR (400 MHz, CDCl3) δ 8.00 (d, J =
7.9 Hz, 1H), 7.79 (d, J = 7.6 Hz, 1H), 7.42 (t, J = 7.5 Hz, 1H), 7.16
(t, J = 7.4 Hz, 1H), 4.39 (s, 2H), 3.62 (s, 2H), 1.97 (s, 4H); 13C NMR
(100 MHz, CDCl3) δ 166.54, 141.30, 135.30, 132.66, 130.88,
127.95, 94.00, 64.83, 44.51, 29.27, 26.07. HRMS (ESI) Calcd for
[C11H12ClIO2+Na]+: 360.9468. Found: 360.9466.
Synthesis of compounds 12–20 (Table 2); general procedure
(1) Mono-substitution products
Butane-1,4-diyl bis(2-iodobenzoate) (20): Solid, m.p. 59–60 °C
1
(lit.6,31. 59–60 °C), IR (KBr): νmax = 1720, 1242, 735 cm−1. H NMR
1, 4-Dichlorobutane (158.8 mg, 1.25 mmol, 10 equiv.), IBX (35 mg,
0.125 mmol, 1 equiv.), TBAB (40 mg, 0.125 mmol, 1 equiv.) were
added to DMSO (1 mL) in succession. The mixture was stirred for 1 h
(400 MHz, CDCl3) δ 8.00 (d, J = 7.9 Hz, 2H), 7.81 (dd, J = 7.7,
1.1 Hz, 2H), 7.42 (t, J = 7.5 Hz, 2H), 7.23–7.11 (m, 2H), 4.44 (s, 4H),
2.00 (s, 4H); 13C NMR (100 MHz, CDCl3) δ 166.58, 141.30, 135.35,
132.62, 130.90, 127.94, 94.00, 65.14, 25.50.
o
at 80 C, then cooled to rt. Ethyl acetate (10 mL) was added to the
solution and this was washed with brine (10 mL). The organic layer
was dried over MgSO4 and evaporated in vacuo. The crude product
was purified by preparative TLC (eluent: PE/EtOAc, 6:1) to give 19.
Synthesis of bis(2-iodoxybenzoate esters)8; typical procedure
Dichloromethane (20 mL) was added to a vigorously stirred suspen-
sion of ethylene bis(2-iodobenzoate) (5 mmol) and sodium hypochlo-
rite solution (5% NaOCl, 30mL), and then acetic acid (10 mL) was
added dropwise over 10 min at room temperature. The resulting
mixture was stirred overnight. The DCM was evaporated in a vacuum
and acetone (50 mL) was added to precipitate the product, which was
then filtered and washed with DCM (2×20 mL), acetone (2×20 mL),
dried under vacuum to give analytically pure form as white solids 21;
yield: 1.8 g (63%).
(2) Bi-substitution products
1,4-Dichlorobutane (137.2 mg, 0.29 mmol, 1 equiv.), IBX/TBAB
(2 equiv.) were added to DMSO (2 mL) in succession, and heated to
80 °C, then another 4.5 equiv. was added in three portions at t=30 min
(1 equiv.), 50 min (2 equiv.), 90 min (1.5 equiv.). The mixture was
stirred for another 30 min, then cooled to rt. Ethyl acetate (10 mL) was
added to the solution, and this was washed with brine (10 mL). The
organic layer was dried over MgSO4 and evaporated in vacuo. The
crude product was purified by preparative TLC (eluent: PE/EtOAc,
6:1) to give 20.
Ethane-1,2-diyl bis(2-iodoxybenzoate esters) (21): Solid, m.p.
1
165 °C dec, IR (KBr): νmax = 1687, 1380, 783, 748 cm−1; H NMR
Methane-1,1-diyl bis(2-iodobenzoate) (12): Solid, m.p.72–74 °C,
(400 MHz, DMSO) δ 8.27 (d, J = 7.5 Hz, 2H), 8.16 (d, J = 7.3 Hz,
2H), 8.04 (t, J = 7.1 Hz, 2H), 7.76 (t, J = 7.1 Hz, 2H), 4.82
(s, 4H); 13C NMR (100 MHz, DMSO) δ 167.29, 151.13, 135.39,
132.52, 131.05, 126.09, 123.63, 64.94. HRMS (ESI) Calcd for
[C16H12I2O8+Na]+: 608.8519. Found: 608.8502.
1
IR (KBr): νmax = 1745, 1234, 1036, 736 cm−1; H NMR (400 MHz,
CDCl3) δ 8.02 (d, J = 7.9 Hz, 2H), 7.93 (d, J = 7.4 Hz, 2H), 7.41 (t,
J = 7.5 Hz, 2H), 7.18 (t, J = 7.3 Hz, 2H), 6.24 (s, 2H); 13C NMR
(100 MHz, CDCl3) δ 164.71, 141.77, 133.44, 133.18, 131.75, 128.04,
94.75, 80.48. HRMS (ESI) Calcd for [C15H10I2O4+Na]+: 530.8566.
Found: 530.8568.
Butane-1,4-diyl bis(2-iodoxybenzoate esters) (22): Solid, m.p.
1
206–207 °C dec, IR (KBr): νmax = 1672, 1300, 770 cm−1; H NMR
2-Chloroethyl 2-iodobenzoate (13): Oil, IR (KBr): νmax = 1730,
(400 MHz, DMSO) δ 8.27 (d, J = 7.7 Hz, 2H), 8.13 (d, J = 7.4 Hz,
2H), 8.04 (t, J = 7.4 Hz, 2H), 7.77 (t, J = 7.3 Hz, 2H), 4.51 (s, 4H),
1.96 (s, 4H); 13C NMR (100 MHz, DMSO) δ 167.41, 151.01, 135.21,
132.44, 130.66, 126.49, 123.64, 66.82, 25.14. HRMS (ESI) Calcd for
[C18H16I2O8+Na]+: 636.8832. Found: 636.8817.
1
1247, 742 cm−1; H NMR (400 MHz, CDCl3) δ 8.01 (d, J = 7.8 Hz,
1H), 7.88 (d, J = 7.5 Hz, 1H), 7.43 (t, J = 7.4 Hz, 1H), 7.18 (t, J =
7.4 Hz, 1H), 4.60 (t, J = 5.4 Hz, 2H),3.84 (t, J = 5.4 Hz, 2H); 13C
NMR (100 MHz, CDCl3) δ 165.64, 141.34, 134.25, 133.04, 131.22,
128.07, 94.46, 65.09, 41.87. HRMS (ESI) Calcd for [C9H8ClIO2+Na]+:
332.9155. Found: 332.9158.
This work was supported by National Natural Science Founda-
tion of China (20972109).
2-Bromoethyl 2-iodobenzoate (15): Oil, IR (KBr): νmax = 1730,
1
1249, 742 cm−1; H NMR (400 MHz, CDCl3) δ 7.98 (d, J = 7.9 Hz,
1H), 7.86 (d, J = 7.7 Hz, 1H), 7.40 (t, J = 7.6 Hz, 1H), 7.15 (t, J =
7.6 Hz, 1H), 4.63 (t, J = 6.1 Hz, 2H), 3.64 (t, J = 6.1 Hz, 2H); 13C
NMR (100 MHz, CDCl3) δ 165.80, 141.48, 134.27, 133.02, 131.30,
128.04,94.35,64.82,28.58.HRMS(ESI)Calcdfor[C9H879BrIO2+Na]+:
376.8650. Found: 376.8646.
Received 31 January 2012; accepted 15 March 2012
Paper 1201139 doi: 10.3184/174751912X13345951125194
Published online: 10 May 2012
Ethane-1,2-diyl bis(2-iodobenzoate) (14): Solid, m.p. 58–59 °C
1
(lit.6,31. 58–59 °C)IR (KBr): νmax = 1723, 1242, 734 cm−1; H NMR
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(400 MHz, CDCl3) δ 7.95 (d, J = 7.9 Hz, 2H), 7.83 (d, J = 7.7 Hz,
2H), 7.37 (t, J = 7.6 Hz, 2H), 7.11 (dd, J = 11.3, 3.9 Hz, 2H), 4.68 (s,
4H); 13C NMR (100 MHz, CDCl3) δ 166.10, 141.42, 134.52, 132.93,
131.30, 128.02, 94.33, 63.15.
3-Chloropropyl 2-iodobenzoate (16): Oil, IR (KBr): νmax = 2962,
1
1729, 1289, 1131, 742 cm−1; H NMR (400 MHz, CDCl3) δ 7.99 (d,
J = 7.9 Hz, 1H),7.78 (d, J = 7.7 Hz, 1H), 7.41 (t, J = 7.5 Hz, 1H), 7.16
(t, J = 7.6 Hz, 1H), 4.50 (t, J = 6.0 Hz, 2H), 3.72 (t, J = 6.4 Hz, 2H),
7
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