Oligonaphthalene Derivatives
FULL PAPER
stirred for 1 h. Saturated NH4Cl solution was added to quench the reac-
tion and the solvent was removed in vacuo. The residue was extracted
with CH2Cl2 and the combined organic extracts were dried over MgSO4
before being concentrated to give the crude diol. Without further purifi-
cation, the crude intermediate was dissolved in THF (10 mL). To this so-
lution was added CH3I (0.1 mL, 1.62 mmol) and NaH (60% in mineral
oil, 0.1 g, 2.50 mmol). After the alkylation reaction proceeded for 16 h,
the excess NaH was quenched with saturated NH4Cl solution and the sol-
vent was removed in vacuo. The residue was extracted with CH2Cl2 and
the combined organic phase was dried over MgSO4 and concentrated.
The crude product was purified by performing flash chromatography
(silica gel; CH2Cl2/diethyl ether 15:1) to give pure 8 (0.11 g, 38%).
1H NMR (500 MHz, CDCl3, TMS): d=0.69–1.58 (m, 28H), 3.15 (s, 6H),
3.15–3.45 (m, 8H), 7.30 (d, J=8.5 Hz, 4H), 7.31–7.48 (m, 8H), 7.55 (d,
J=8.5 Hz, 4H), 7.70–7.97 (m, 8H), 7.98 ppm (d, J=9.5 Hz, 4H);
13C NMR (100 MHz, CDCl3, TMS): d=13.46, 13.90, 19.60, 20.26, 29.67,
30.70, 44.45, 48.66, 52.44, 87.23, 126.08, 126.22, 126.95, 127.22, 127.42,
127.46, 127.61, 128.09, 128.38, 128.77, 131.84, 132.43, 132.81, 136.05,
140.64, 141.31, 144.60, 171.39 ppm; IR (KBr): n˜ =2944, 2868, 1631, 1461,
1432, 1082, 816, 742, 481 cmÀ1; HRMS: m/z: calcd for C64H71N2O4:
931.5414 [M+H+]; found: 931.5405.
combined extracts were dried over MgSO4 and concentrated to give the
crude diol.
The methylation was carried out as in the synthesis of 8 in THF (10 mL)
with NaH and CH3I (0.1 g, 2.50 mmol and 0.10 mL, 1.61 mmol, respec-
tively). After the established work-up procedure, the desired product
(95 mg, 22%) was isolated as a mixture of two diastereomers by perform-
ing flash chromatography (silica gel; CH2Cl2/diethyl ether 8:1). HRMS:
m/z: calcd for C64H71N2O4: 931.5414 [M+H+]; found: 931.5416. For other
spectroscopic data, see Supporting Information.
Compound 12: Under an inert atmosphere, compound 11 was dissolved
(0.12 g, 0.13 mmol) in trifilic acid (1 mL) and the cyclization reaction was
allowed to proceed for 5 min before the reaction was quenched with de-
oxygenated 1.0m NaHCO3 solution. The reaction mixture was extracted
with CH2Cl2 before the combined organic phase was dried over MgSO4
and concentrated in vacuo. Pure product (0.10 g, 93%) was isolated as a
mixture of two diastereomers by performing flash chromatography
(CH2Cl2). HRMS: m/z: calcd for C62H63N2O2: 867.4890 [M+H+]; found:
867.4877. For other spectroscopic data, see Supporting Information.
Compound 13: A THF solution of 2,6-dibromonaphthalene (0.53 g,
1.85 mmol in 16 mL) was cooled to À788C and to this solution nBuLi
(1.6m in hexane, 1.27 mL, 2.03 mmol) was slowly added. After the ex-
Compound 9: Under an inert atmosphere, compound
8 (0.10 g,
change reaction proceeded for 1 h,
a THF solution of 15 (0.72 g.
0.11 mmol) was dissolved in CF3COOH (1 mL). After stirring for 5 min,
the cyclization reaction was quenched with deoxygenated 1.0m NaHCO3
solution. The mixture was extracted with CH2Cl2 and the combined or-
ganic extracts were dried over MgSO4 and concentrated. Purification was
1.85 mmol in 7 mL) was added dropwise. The reaction was then warmed
back to RTand stirred for another 60 min before being quenched with
saturated NH4Cl solution. The volatiles were removed in vacuo and the
residue was extracted with CH2Cl2. The combined organic phase was
dried over MgSO4 and concentrated to give the crude alcohol. Without
further purification, the crude mixture was dissolved in THF solution
(15 mL) and CH3I (0.31 mL, 1.62 mmol) and NaH (60% in mineral oil,
0.12 g, 3.00 mmol) were added to fulfil the methylation. After being
stirred for 3 h at RT, the reaction was quenched with saturated NH4Cl so-
lution and the solvent was evaporated in vacuo. The remaining mixture
was extracted with CH2Cl2 several times and the combined organic phase
was dried over MgSO4 and concentrated. The crude product was purified
by performing flash column chromatography (CH2Cl2) to give 13 (0.53 g,
48%) as an amorphous solid. 1H NMR (500 MHz, CDCl3, TMS): d=
0.68–1.60 (m, 14H), 3.15 (s, 3H), 3.15–3.46 (m, 4H), 7.32 (d, J=8 Hz,
2H), 7.45–7.47 (m, 3H), 7.53 (m, 4H), 7.65 (dd, J=1.2, 8 Hz, 2H), 7.76–
7.81 (m, 3H), 7.94–7.97 ppm (m, 3H); 13C NMR (100 MHz, CDCl3,
TMS): d=13.40, 13.87, 19.56, 20.23, 29.63, 30.66, 44.45, 48.62, 52.43,
87.12, 120.13, 126.13, 126.18, 126.24, 126.29, 126.64, 126.87, 127.10, 127.41,
127.55, 127.66, 127.91, 128.35, 128.76, 129.43, 129.99, 131.25, 131.45,
132.44, 132.78, 133.43, 136.15, 140.26, 141.61, 144.26, 171.33 ppm; IR
performed by performing flash chromatography (CH2Cl2) to give
9
(91 mg, 95%). 1H NMR (400 MHz, CDCl3, TMS): d=0.75–1.58 (m,
28H), 3.20–3.44 (m, 8H), 5.25 (s, 2H), 7.17 (m, J=8 Hz, 4H), 7.24–7.29
(m, 4H), 7.45–7.60 (m, 8H), 7.85 (d, J=8 Hz, 2H), 7.98 (dd, J=1.2,
8 Hz, 2H), 8.62–8.65 (m, 2H), 8.76 ppm (d, J=8 Hz, 2H); 13C NMR
(125 MHz, CDCl3, TMS): d=13.55, 13.89, 19.67, 20.27, 29.69, 30.75,
44.54, 48.73, 55.61, 121.33, 121.43, 122.87, 125.33, 126.81, 126.85, 127.06,
127.13, 128.45, 128.59, 128.63, 128.89, 129.95, 134.23, 136.16, 137.84,
137.92, 138.25, 138.36, 141.39, 146.46, 147.38, 147.50, 171.48 ppm; IR
(KBr): n˜ =2957, 2927, 2864, 1631, 1465, 1428, 809, 750 cmÀ1; HRMS: m/z:
calcd for C62H63N2O2: 867.4890 [M+H+]; found: 867.4884.
Bis-4,4’-(N,N-dibutylbenzamide)-(1,5-naphthalenediyldicarbonyl)
(10):
Under a nitrogen atmosphere a THF solution N,N-dibutyl-4-iodobenza-
mide (2.92 g, 8.14 mmol in 20 mL) was immersed in an ice bath and cy-
clopentylmagnesium bromide (1.3m in THF, 6.88 mL, 8.95 mmol) was
slowly added. The exchange reaction was stirred for 20 min before
powder of compound 1,5-naphthyl dialdehyde (0.5 g, 2.71 mmol) was
added. The reaction was stirred at RT for 1 h before being quenched
with NH4Cl solution. The THF and other volatiles were removed in
vacuo and the residue was extracted with CH2Cl2. The combined organic
extracts were dried over MgSO4 and concentrated to give the crude diol.
(KBr): n˜ =2955, 2932, 2868, 1630, 1461, 1428, 1078, 812, 743, 477 cmÀ1
;
HRMS: m/z: calcd for C37H3979BrNO2: 608.2164 [M+H+]; found:
608.2167.
N,N-Dibutyl-4-(naphthalene-2-carbonyl)-benzamide (15): N,N-Dibutyl-4-
iodobenzamide (3.24 g, 9.02 mmol) was dissolved in THF (30 mL) and to
this solution was slowly added cyclopentylmagnesium bromide (1.0m in
THF, 10 mL, 10.00 mmol). The exchange reaction was allowed to proceed
for 20 min and a THF solution of 2-naphthaldehyde (1.30 g, 8.32 mmol in
30 mL) was added. The reaction was stirred at RT for 1 h before being
quenched with saturated NH4Cl solution. The volatiles were removed in
vacuo and the residue was extracted with CH2Cl2. The combined organic
phase was dried over MgSO4 and concentrated to furnish the crude alco-
hol that underwent subsequent oxidation without further purification.
The subsequent oxidation was carried out with the unpurified diol in
CH2Cl2 solution (70 mL) with pyridinium chlorochromate (2.34 g,
10.84 mmol) as the oxidant. The oxidation was accomplished in 2 h and
the chromiumACHTREUNG(III) side products were removed by passing the reaction
mixture through a short silica-gel column. Pure compound 10 (1.08 g,
62%) was obtained by performing further flash chromatography (silica
gel; CH2Cl2/diethyl ether 10:1). 1H NMR (400 MHz, CDCl3, TMS): d=
0.76–1.62 (m, 28H), 3.14–3.50 (m, 8H), 7.43 (d, J=8.0 Hz, 4H), 7.54 (t,
J=7.9 Hz, 2H), 7.61 (d, J=7.9 Hz, 2H), 7.88 (d, J=8.0 Hz, 4H),
8.24 ppm (d, J=7.9 Hz, 2H); 13C NMR (125 MHz, CDCl3, TMS): d=
13.61, 13.90, 19.75, 20.28, 29.60, 30.80, 44.52, 48.71, 125.83, 126.66, 128.29,
128.95, 130.57, 131.16, 136.48, 138.29, 142.18, 170.40, 197.04 ppm; IR
(KBr): n˜ =2958, 2928, 2872, 1663, 1635, 1273, 981, 796 cmÀ1; HRMS: m/z:
calcd for C42H51N2O4: 647.3849 [M+H+]; found: 647.3841.
The crude alcohol was dissolved in CH2Cl2 (50 mL) and to this solution
was added pyridinium chlorochromate (3.89 g, 18.04 mmol). The reaction
was stirred at RTfor 50 min and the mixture was passed through a short
silica-gel column to remove chromium side products. Flash column chro-
matography (silica gel; CH2Cl2/hexane 8:1) was performed and yielded
15 (2.40 g, 82%) as an amorphous solid. 1H NMR (400 MHz, CDCl3,
TMS): d=0.77–1.65 (m, 14H), 3.17–3.52 (m, 4H), 7.48 (d, J=8 Hz, 2H),
7.53–7.62 (m, 2H), 7.84–7.93 (m, 6H), 8.22 ppm (s, 1H); 13C NMR
(100 MHz, CDCl3, TMS): d=13.63, 13.91, 19.74, 20.28, 29.61, 30.82,
44.50, 48.73, 125.53, 126.42, 126.91, 127.80, 128.44, 128.51, 129.46, 130.11,
132.17, 132.21, 134.41, 135.36, 138.36, 141.08, 170.63, 196.21 ppm; IR
(KBr): n˜ =2957, 2931, 2871, 1656, 1631, 1465, 1428, 1292, 783, 753,
Compound 11: To
a THF solution of 1-bromonapthalene (0.22 g,
1.07 mmol in 3 mL) was slowly added nBuLi solution (2.5m in hexane,
0.43 mL, 1.07 mmol) at À788C. The exchange reaction was finished after
1 h. A THF solution of 10 (0.5 g, 1.72 mmol in 5 mL) was slowly added
before the reaction was warmed back to RTand stirred for another 1 h.
The reaction was quenched with saturated NH4Cl. The volatiles were re-
moved in vacuo and the residual mixture was extracted with CH2Cl2. T he
Chem. Eur. J. 2008, 14, 2777 – 2787
ꢁ 2008 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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