Zinc(II) Specific Fluorophore Zinquin Ester
J . Org. Chem., Vol. 65, No. 24, 2000 8209
7.25-7.51 (6H, m), 7.83 (2H, d, J ) 8.1 Hz), 7.86 (1H, d, J )
8.4 Hz), 9.21 (1H, bs); MS m/z 457 (M, 10), 302 (M - C7H7-
SO2, 30); HRMS calcd for C27H24N2O3S 456.1508, found m/z
456.1518.
8.4 Hz), 9.25 (1H, bs); MS m/z 372 (M, 33), 217 (M - C7H7-
SO2, 100), 91 (63).
Eth yl 2-(2-[(E)-2-P h en yl-1-eth en yl]-6-qu in olyloxy-8-p-
tolu en esu lfon a m id o)a ceta te (27). To a suspension of so-
dium hydride (0.097 g, 2.22 mmol) in DMF (10 mL) at 0 °C
was added a solution of the phenol 24 (0.840 g, 2.01 mmol) in
DMF (20 mL) and the reaction mixture stirred for 20 min.
under an N2 atmosphere. Ethyl bromoacetate (0.225 mL, 2.01
mmol) was then added and the reaction mixture allowed to
warm to room temperature and then stirred overnight. The
DMF was then removed under vacuum, and the residue was
dissolved in CH2Cl2 (100 mL) and washed with a solution of
saturated NaHCO3 (100 mL). Purfication by flash chromatog-
raphy (CH2Cl2) followed by recrystallization (CH2Cl2/hexane)
yielded the ester 27 as white needles (0.30 g, 30%): mp 178-
4-Meth yl-N-(6-m eth oxy-2-[(E)-2-(1-n aph th y)-1-eth en yl]-
8-qu in olyl)ben zen esu lfon a m id e (19): yellow prisms (0.267
g, 93%); mp 166-168 °C; 1H NMR δ_2.29 (3H, s), 3.87 (3H, s),
6.69 (1H, d, J ) 2.4 Hz), 7.17 (2H, d, J ) 8.1 Hz), 7.36 (1H, d,
J ) 16.2 Hz), 7.46 (1H, d, J ) 2.4 Hz), 7.51-7.62 (3H, m),
7.68 (1H, d, J ) 8.7 Hz), 7.83-7.91 (4H, m), 7.94 (1H, d, J )
8.7 Hz), 8.26 (2H, d, J ) 8.1 Hz), 8.33 (1H, d, J ) 16.2 Hz),
9.26 (1H, bs); MS m/z 481 (M, 10), 480 (20), 325 (M-C7H7SO2,
40), 43 (100); HRMS calcd for C29H24N2O3S 480.1508, found
m/z 480.1508. Anal. Calcd for C29H24N2O3S: C, 72.5; H, 5.0;
N, 5.8. Found: C, 72.5; H, 5.2; N, 5.9.
4-Meth yl-N-(6-m eth oxy-2-[(E)-2-(2-n aph th y)-1-eth en yl]-
8-qu in olyl)ben zen esu lfon a m id e (20): yellow prisms (0.204
g, 85%); mp 185-187 °C; 1H NMR δ_2.29 (3H, s), 3.85 (3H, s),
6.67 (1H, d, J ) 2.5 Hz), 7.16 (2H, d, J ) 8.1 Hz), 7.39 (1H, d,
J ) 16.2 Hz), 7.43, 1H, d, J ) 2.5 Hz), 7.47-7.51 (2H, m),
7.61 (1H, d, J ) 8.5 Hz), 7.73 (1H, d, J ) 16.2 Hz), 7.82-7.87
(6H, m), 7.91, 1H, d, J ) 8.5 Hz), 7.99 (1H, m), 9.28 (1H, bs);
MS m/z 481 (M, 10), 447 (99), 325 (M - C7H7SO2, 20), 168
(26), 84 (100); HRMS calcd for C29H24N2O3S 480.1508, found
m/z 480.1515.
1
179.5 °C; IR (KBr) υ 3325, 1760, 1610, 1600 cm-1; H NMR δ
1.29 (3H, t, J ) 7.2 Hz), 2.29 (3H, s), 4.27 (2H, q, J ) 7.2 Hz),
4.67 (2H, s), 6.62 (1H, d, J ) 2.7 Hz), 7.17 (2H, d, J ) 8.4 Hz),
7.29 (1H, d, J ) 16.2 Hz), 7.33-7.44 (3H, m), 7.51 (1H, d, J )
2.7 Hz), 7.55 (1H, d, J ) 16.2 Hz), 7.58 (1H, d, J ) 8.6 Hz),
7.63 (2H, m), 7.83 (2H, d, J ) 8.4 Hz), 7.88 (1H, d, J ) 8.6
Hz), 9.25 (1H, bs); MS m/z 502 (M, 100), 347 (M - C7H7SO2,
45), 319 (15), 232 (25), 91 (24). Anal. Calcd for C28H26N2O5S:
C, 66.9; H, 5.2; N, 5.6. Found: C, 66.8; H, 5.4; N, 5.7.
E t h yl 2-[2-(2-Met h yl-1-p r op en yl)-6-q u in olyloxy-8-p -
tolu en esu lfon a m id o]a ceta te (28). The phenol 25 (0.215 g,
0.583 mmol), ethyl bromoacetate (0.065 mL, 0.59 mmol), and
potassium carbonate (0.081 g, 0.59 mmol) were refluxed in dry
acetone (15 mL) for 4 h under N2. The solvent was then
removed under vacuum, the residue was dissolved in CH2Cl2
and washed with a solution of saturated NaHCO3. The crude
product was purified by flash chromatography and then
recrystallized from CH2Cl2/hexane yielding the ester 28 as
white needles (0.182 g, 67%): mp 149-151 °C; 1H NMR δ 1.29
(3H, t, J ) 6.9 Hz), 2.01 (3H, d, J ) 1.4 Hz), 2.19 (3H, d, J )
1.4 Hz), 2.29 (3H, s), 4.27 (2H, q, J ) 6.9 Hz), 4.66 (2H, s),
6.37 (1H, t, J ) 1.4 Hz), 6.61 (1H, d, J ) 2.6 Hz), 7.16 (2H, d,
J ) 8.3 Hz), 7.22 (1H, d, J ) 8.6 Hz), 7.51 (1H, d, J ) 2.6 Hz),
7.78 (2H, d, J ) 8.3 Hz), 7.82 (1H, d, J ) 8.6 Hz), 9.15 (1H,
bs); MS m/z 454 (M, 52), 299 (M - C7H7SO2, 100), 184 (20), 91
(21). Anal. Calcd for C24H26N2O5S: C, 63.4; H, 5.8; N, 6.2.
Found: C, 63.1; H, 5.8; N, 6.3.
4-Me t h yl-N -(6-m e t h oxy-2-(2-m e t h yl-1-p r op e n yl)-8-
qu in olyl)ben zen esu lfon a m id e (21): white prisms (0.244 g,
91%); mp 158-160 °C; 1H NMR δ 2.00 (3H, m), 2.19 (3H, m),
2.27 (3H, s), 3.83 (3H, s), 6.36 (1H, m), 6.63 (1H, d, J ) 2.4
Hz), 7.13 (1H, d, J ) 8.3 Hz), 7.20 (1H, d, J ) 8.4 Hz), 7.24
(1H, d, J ) 2.4 Hz), 7.77 (1H, d, J ) 8.3 Hz), 7.82 (1H, d, J )
8.4 Hz), 9.13 (1H, bs); MS m/z 382 (M, 50), 227 (M - C7H7-
SO2, 100). Anal. Calcd for C21H22N2O3S: C, 66.0; H, 5.8; N,
7.3. Found: C, 65.7; H, 5.8; N, 7.2.
4-Meth yl-N-(2-isobu tyl-6-m eth oxy-8-qu in olyl)ben zen e-
su lfon a m id e (23): white needles (0.490 g, 85%); mp 154-
156 °C; 1H NMR δ 0.91 (6H, m), 2.13 (1H, m), 2.27 (3H, s),
2.72 (2H, m), 3.84 (3H, s), 6.66 (1H, d, J ) 2.7 Hz), 7.12 (1H,
d, J ) 8.3 Hz), 7.16 (1H, d, J ) 8.4 Hz), 7.43 (1H. d. J ) 2.7
Hz), 7.76 (2H, d, J ) 8.3 Hz), 7.82 (1H, d, J ) 8.4 Hz), 9.25
(1H, bs); MS m/z 384 (M, 33), 229 (M-C7H7SO2, 30), 187 (88),
69 (100). Anal. Calcd for C21H24N2O3S: C, 65.6; H, 6.3; N, 7.3.
Found: C, 65.9; H, 6.5; N, 7.3.
Eth yl 2-(2-Isobu tyl-6-qu in olyloxy-8-p-tolu en esu lfon a -
m id o)a ceta te (29). The phenol 26 (0.334 g, 0.90 mmol) was
refluxed with ethyl bromoacetate (0.100 mL, 0.90 mmol) and
potassium carbonate (0.124 g, 0.90 mol) in dry acetone (15 mL)
for 4 h under N2. The solvent was then removed under vacuum,
and the crude solid was dissolved in CH2Cl2 and washed with
saturated NaHCO3. Purification by flash chromatography
followed by recystallisation from CH2Cl2/hexane yielded the
ester 29 as a white solid (0.375 g, 90%): mp 146.5-148.5 °C;
1H NMR δ 0.90 (6H, m), 1.29 (3H, t, J ) 7.2 Hz), 2.11 (1H, m),
2.28 (3H, s), 2.72 (2H, d, J ) 6.9 Hz), 4.27 (2H, q, J ) 7.2 Hz),
4.66 (2H, s), 6.63 (1H, d, J ) 2.6 Hz), 7.12 (2H, d, J ) 8.5 Hz),
7.17 (1H, d, J ) 8.3 Hz), 7.54 (1H, d, J ) 2.6 Hz), 7.77 (2H, d,
J ) 8.5 Hz), 7.82 (1H, d, J ) 8.3 Hz), 9.26 (1H, bs); IR (KBr)
υ 3260, 1760, 1630, 1610, 1590 cm-1; MS m/z 456 (M, 77), 414
(20), 301 (M-C7H7SO2, 32), 259 (100), 155 (19), 91 (55). Anal.
Calcd for C24H28N2O5S: C, 63.1; H, 6.2; N, 6.2. Found: C, 63.0;
H, 6.3; N, 6.2.
Gen er a l P r oced u r e for th e Dem eth yla tion of th e
Meth oxy Com p ou n d s. To a solution of boron tribromide (2.5
equiv) in dry CH2Cl2 under N2 was added dropwise a solution
of the sulfonamide (1 equiv) in dry CH2Cl2. The reaction
mixture was refluxed for 4 h then stirred for 16 h. Water was
added cautiously to the mixture, which was basified with a
solution of saturated NaHCO3 and the aqueous layer extracted
with CH2Cl2. The organic extracts were combined and dried,
and the solvent was removed under vacuum. The crude solid
was then used directly in the next step.
4-Met h yl-N-(6-h yd r oxy-2-[(E)-2-p h en yl-1-et h en yl]-8-
qu in olyl)ben zen esu lfon a m id e (24): orange crystalline solid
1
(0.85 g, 84%); mp 242-245 °C; H NMR δ_1.93 (3H, s), 6.36
(1H, d, J ) 2.4 Hz), 6.83 (2H, d, J ) 8.3 Hz), 6.90 (1H, d, J )
16.5 Hz), 7.06 (1H, d, J ) 2.4 Hz), 6.98-7.07 (3H, m), 7.16-
7.29 (5H, m), 7.44 (2H, d, J ) 8.3 Hz), 7.49 (1H, d, J ) 8.7
Hz), 9.31 (1H, bs); MS m/z 416 (M, 100), 261 (M - C7H7SO2,
90), 91 (55), 77 (30).
4-Me t h yl-N -[6-h yd r oxy-2-(2-m e t h yl-1-p r op e n yl)-8-
qu in olyl]ben zen esu lfon a m id e (25): yellow oil (0.22 g, 98%);
1H NMR δ 1.98 (3H, s), 2.15 (3H, s), 2.16 (3H, s), 6.32 (1H, m),
6.72 (1H, m), 7.03 (2H, d, J ) 8.4 Hz), 7.11 (1H, d, J ) 8.5
Hz), 7.49 (1H, m), 7.68 (1H, d, J ) 8.5 Hz), 7.74 (2H, d, J )
8.4 Hz), 9.28 (1H, bs); MS m/z 368 (M, 29), 213 (M - C7H7-
SO2, 100), 198 (20), 91 (32).
Ack n ow led gm en t. This work was supported by the
NHMRC. We thank Dr. W. H. Betts (Queen Elizabeth
Hospital, Adelaide) for help with the fluorescence work.
Su p p or tin g In for m a tion Ava ila ble: X-ray data for 9;
tabulated fluorescence values (Table S2) for 17-21 and 23
with a number of metal cations; tabulated fluorescence values
(Table S3) of 1 and 27-29 in the absence and presence of zinc-
(II), and 1H NMR spectra of 7, 18, and 20. This material is
4-Meth yl-N-(2-isobu tyl-6-h yd r oxy-8-qu in olyl)ben zen e-
su lfon a m id e (26): orange needles (0.37 g, 87%); mp 147-
1
149 °C; H NMR (CDCl3, 300 MHz) δ 0.90 (6H, m), 2.10 (1H,
m), 2.27 (3H, s), 2.71 (2H, d, J ) 7.2 Hz), 6.71 (1H, d, J ) 2.5
Hz), 7.12 (2H, d, J ) 8.4 Hz), 7.15 (1H, d, J ) 8.5 Hz), 7.42
(1H, d, J ) 2.5 Hz), 7.75 (2H, d, J ) 8.5 Hz), 7.79 (1H, d, J )
J O000678X