Sørensen et al.
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the reaction was quenched with brine, the product extracted (3 ꢀ
100 mL heptane), and the combined organic phases dried
(MgSO4) and evaporated to a colorless oil, which was purified
by dry column chromatography (gradient from heptane to 10%
sulfide complex (1 mL; 10 mmol) was then added dropwise and
the reaction was left at rt overnight. Excess borane was de-
stroyed by careful addition of MeOH (5 mL) and the solu-
tion was stirred until no more hydrogen gas evolved (1 h).
The product was purified by aqueous workup and extraction
(heptane), followed by column chromatography (SiO2, toluene)
to yield the product 38 as a red oil (489 mg, 85%) that quickly
turned black upon standing. 1H NMR (300 MHz, CDCl3) δ 7.37
(d, J = 8.6 Hz, 2H), 6.61-6.54 (m, 4H), 4.17-3.91 (br, 2H), 3.75
(t, J = 5.8 Hz, 4H), 3.55 (t, J = 5.8 Hz, 4H), 1.83 (m, 4H),
1.33-0.99 (m, 32H), 0.85 (t, J = 6.9 Hz, 6H) ppm; 13C NMR
(75 MHz, CDCl3) δ 151.9, 145.8, 133.1, 119.4, 112.2, 108.6, 55.0,
46.3, 43.9, 41.1, 32.1, 30.4, 29.9, 29.8, 29.6, 29.5, 24.0, 22.9, 14.3
ppm; MS (FAB) m/z 600 [Mþ].
1
EtOAc in heptane) to afford the product 34 (19.9 g, 75%). H
NMR (400 MHz, CDCl3) δ 7.69 (d, J = 7.34 Hz, 2H), 7.36-7.21
(m, 6 H), 2.00-1.88 (m, 4 H), 1.34-0.95 (m, 32 H), 0.90-0.80
(m, 6 H) ppm; 13C NMR (100 MHz, CDCl3) δ 150.9, 141.3,
127.2, 126.9, 123.0, 119.8, 55.2, 40.6, 32.1, 30.3, 29.8 (2 peaks),
29.5 (2 peaks), 24.0, 22.9, 14.3 ppm; MS (GC-MS) m/z 446.5
[Mþ], 305.3 ([M - C10H21]þ).
9,9-Didecyl-2,7-dinitro-9H-fluorene (35). 9,9-Didecylfluorene
34 (1.0 g, 2.24 mmol) was added dropwise to an ice-cooled
mixture of glacial acetic acid (5 mL) and fuming nitric acid
(5 mL) while the temperature was kept below 10 °C. The solu-
tion was stirred at rt until the next day and was then quenched
with ice water, extracted (3 ꢀ 25 mL EtOAc/heptane, 50:50),
dried (MgSO4), evaporated to dryness, purified by column
chromatography (SiO2, 5% EtOAc in heptane), and recrystal-
lized from MeOH to yield 35 as yellow crystals (550 mg, 46%).
Mp 64-65 °C; IR 3090 (w, aryl C-H stretch), 2925, 2853 (s,
1,10-(9,9-Didecyl-9H-fluorene-2,7-diyl)diaziridine (39). Sodium
hydride (30 mg, 60 wt % in oil, 1.5 mmol) was added to DMSO
(12 mL), and the mixture was stirred for 1 h under an atmo-
sphere of argon. Then chloroethyl amine 38 (300 mg, 0.5 mmol)
was dissolved in DMSO (6 mL) and added dropwise to the
sodium hydride mixture. After 15 min, the solution was heated
to 40 °C and stirred overnight and then quenched with brine
(200 mL). The product was extracted (3 ꢀ 25 mL, 50% EtOAc in
heptane), dried (Na2SO4), evaporated to dryness, and purified
by column chromatography (SiO2, 10% NEt3 in heptane) to
yield 39 as a stable, light yellow oil (197 mg, 75%). 1H NMR (400
MHz, CDCl3) δ 7.43 (d, J = 8.0 Hz, 2H), 6.94 (br, 2H), 6.93
(dd, J=8.0 Hz, J = 2.0 Hz, 2H), 2.13 (s, 4 H) 1.87 (m, 4H),
1.30-1.00 (br, 32H), 0.85 (t, J = 7.1 Hz, 6H) ppm; 13C NMR
(100 MHz, CDCl3) δ 154.1, 151.8, 136.0, 119.7, 119.3, 115.8,
55.0, 40.7, 32.1, 30.3, 29.8 (2 peaks), 29.5 (2 peaks), 28.2, 23.9,
22.9, 14.3 ppm; MS (FAB) m/z 528 [Mþ]; HR-MS m/z 529.4509
(M þ Hþ calcd for C37H57N2 529.4522).
alkane C-H stretch), 1520, 1339 (s, nitro N-O stretch) cm-1
;
1H NMR (300 MHz, CDCl3) δ 8.33 (dd, J = 8.4 Hz, J = 2.1 Hz,
2H), 8.27 (d, J = 2.1 Hz, 2H), 7.92 (d, J = 8.4 Hz, 2H), 2.10 (m,
4H), 1.31-0.95 (br, 32H), 0.84 (t, J = 6.9 Hz) ppm; 13C NMR
(75 MHz, CDCl3) δ 153.7, 148.6, 144.9, 123.8, 121.8, 118.7, 56.7,
40.0, 32.1, 29.9, 29.7 (2 peaks), 29.4 (2 peaks), 24.0, 22.9, 14.3
ppm; MS (ES) m/z 559.4 ([M þ Naþ]). Anal. Calcd for C33H48-
N2O4: C 73.84, H 9.01, N 5.22. Found: C 73.55, H 9.02, N 5.26.
9,9-Didecyl-9H-fluorene-2,7-diamine (36). Compound 35
(1.0 g, 1.86 mmol) was dissolved in EtOAc (20 mL) and Pd/C
(20 mg, 10% Pd on carbon) was added, then the mixture was
shaken in a Parr hydrogenator at 4 bar of hydrogen overnight.
The solution was filtered and evaporated to an oil, which was
purified by column chromatography (10% EtOAc in toluene) to
yield the product 36 as a red oil (700 mg, 90%). IR 3459 (N-H
stretch), 3370 (N-H stretch), 3030 (w), 3004 (w), 2925 (s), 2852
2,7-Bis(fullero[c]pyrrolidin-1-yl]-9,90-didecyl-9H-fluorene (40).
Method I. C60 (200 mg, 0.28 mmol) and the diaziridine 39 (20 mg,
0.04 mmol) were dissolved in 1,2-dichlorobenzene (10 mL) and
the solution was sonicated under a stream of argon for 10 min.
The solution was heated to 200 °C in a sealed glass tube for 15 h
and then cooled to rt. The product, along with unreacted C60,
was precipitated by the addition of MeOH and then purified by
column chromatography (SiO2, cyclohexane/o-xylene) to yield
the product 40 as a black powder (4 mg, 5%). IR 2921 (s), 2849
(s), 1618 (s), 1468 (s), 808 (m) cm-1 1H NMR (400 MHz,
;
CDCl3) δ 7.33 (d, J = 7.8 Hz, 2H), 6.66-6.59 (m, 4H),
1.85-1.78 (m, 4H), 1.30-0.98 (m, 32H), 0.85 (t, J = 7.0 Hz,
6H) ppm; 13C NMR (100 MHz, CDCl3) δ 151.8, 144.5, 133.4,
119.2, 114.1, 110.3, 54.8, 41.1, 32.1, 30.5, 29.9, 29.8, 29.6, 29.5,
24.0, 22.9, 14.3 ppm; MS (EI) m/z 476.5 [Mþ]; HR-MS m/z
477.4226 (M þ Hþ calcd for C33H53N2 477.4209).
1
(m), 1611 (m), 1465 (m), 526 (m) cm-1; H NMR (500 MHz,
CDCl3) δ 7.42 (d, J = 8.0 Hz, 2 H), 7.00 (m, 2H), 6.97 (m, 2H),
5.00 (s, 8H), 1.90-1.83 (m, 4H), 1.06-0.88 (m, 32H), 0.66-0.57
(m, 6H) ppm; 13C NMR (125 MHz, CDCl3) δ 154.3, 147.4,
146.4, 146.2, 145.9, 145.7, 145.4, 144.6, 143.2, 142.8, 142.3,
142.2, 142.0, 140.4, 136.3 (one fullerene signal missing), 69.9,
63.7, 32.5, 30.4, 30.3 (2 signals), 30.23 (2 signals), 30.0 (2 signals),
23.5, 14.8 ppm; MS (MALDI-TOF, negative mode) m/z 1970
[M-].
Method II. C60 (500 mg; 0.69 mmol), paraformaldehyde
(25 mg, 0.8 mmol), and compound 42 (60 mg, 0.07 mmol) were
dissolved in 1-chloronaphthalene (10 mL), and the mixture was
sonicated under a stream of argon for 10 min. The mixture was
refluxed under an atmosphere of nitrogen for 120 min and
was then cooled to rt. The product, along with unreacted C60,
was precipitated by the addition of MeOH, and the product
was purified by column chromatography (SiO2, cyclohexane,
o-xylene) to yield 40 as a black powder (13 mg, 14%).
tert-Butyl 9,9-didecyl-9H-fluorene-2,7-diyldicarbamate (41).
Compound 36 (238 mg; 0.5 mmol), (Boc)2O (218 mg; 1 mmol),
and NaHCO3 (250 mg; 3 mmol) were added to isopropyl alcohol
(5 mL), and the mixture was sonicated at rt for 2 h. The solution
was diluted with water (50 mL) and the product was extracted
with heptane (3 ꢀ 10 mL) and then purified by column chro-
matography (SiO2, EtOAc, heptane) to yield 41 as a white solid
(310 mg, 92%). 1H NMR (CDCl3, 300 MHz) δ 7.52 (d, J = 8
Hz, 2H), 7.31 (br, 4H), 6.54 (2H), 1.89 (m, 2H), 1.54 (s, 18H),
N,N0-(9,9-Didecyl-9H-fluorene-2,7-diyl)bis(2-chloroacetamide)
(37). The diamine 36 (500 mg, 1.05 mmol) and K2CO3 (320 mg,
2.3 mmol) were dissolved in DMF (20 mL) and the mixture was
cooled on an ice bath. Chloroacetyl chloride (250 mg, 176 μL,
2.2 mmol) was added dropwise during 30 min, and the reaction
was then left at rt overnight. The reaction was quenched with
brine (200 mL) and the product was extracted (Et2O, 3 ꢀ
20 mL), dried (Na2SO4), evaporated to dryness, and purified
by column chromatography (SiO2, 20% EtOAc in heptane) to
yield the diamide 37 as a yellow wax (632 mg, 96%). IR 3399 (w),
3299 (m, N-H stretch), 2926 (s), 2853 (s), 1667 (s, CdO stretch),
1698 (m), 1616 (m), 1549 (s), 1469 (s), 819 (m, C-Cl stretch)
cm-1; 1H NMR (300 MHz, CDCl3) δ 8.23 (s, 2H), 7.62 (d, J =
8.2 Hz, 2H), 7.56 (d, J = 1.8 Hz, 2H), 7.50 (dd, J = 8.2 Hz, J =
1.8 Hz, 2H), 4.22 (s, 4H), 1.95 (m, 4H), 1.32-0.95 (m, 32H), 0.85
(t, J = 6.9 Hz, 6H) ppm; 13C NMR (100 MHz, CDCl3) δ 163.7,
152.2, 137.9, 136.0, 120.1, 119.0, 114.8, 55.8, 43.2, 40.6, 32.1,
30.3, 29.8, 29.7, 29.6, 29.5, 24.0, 22.9, 14.3 ppm; MS (FAB) m/z
628 [Mþ]. Anal. Calcd for C37H54Cl2N2O2: C 70.57, H 8.64, N
4.45. Found: C 70.42, H 8.68, N 4.31.
N2,N7-Bis(2-chloroethyl)-9,9-didecyl-9H-fluorene-2,7-di-
amine (38). The chloroethyl amide 37 (600 mg, 0.95 mmol) was
dissolved in dry and degassed THF (40 mL) and the mixture was
cooled to 0 °C under an atmosphere of argon. Borane-dimethyl
262 J. Org. Chem. Vol. 76, No. 1, 2011