4
A. Garrido Montalban et al. / Tetrahedron xxx (2014) 1e5
4.5. Dipyrromethane (8)
Calcd for C29H35N3O6: C, 66.78; H, 6.76; N, 8.06. Found: C, 66.76; H,
6.64; N, 7.84.
The same reaction as above with ethyl pyrrole ester 4 (0.39 g,
2.0 mmol), gave after chromatography (CH2Cl2/hexanes 7:1)
dipyrromethane 8 (0.34 g, 65%) as a yellow solid: Rf 0.10 (CH2Cl2/
hexanes 7:1); mp 139 ꢀC; IR (film) 3347, 1689, 1644, 1460, 1348,
4.9. BODIPY (12)
To a solution of dipyrromethene 11 (60 mg, 0.12 mmol) in dry
toluene (5 mL), BF3$OEt2 (0.72 mL, 5.7 mmol) was added dropwise
at 20 ꢀC under N2. The mixture was allowed to stir at 20 ꢀC for
10 min, after which Et3N (0.43 mL, 3.1 mmol) was added dropwise,
whereby the solution turned from dark purple to red. After stirring
for a further 30 min at 20 ꢀC, the reaction mixture was neutralized
with 2 M HCl, extracted with EtOAc (3ꢁ10 mL), dried (MgSO4),
rotary evaporated, and chromatographed (hexanes/EtOAc
4:1e2.3:1) to give complex 12 (62 mg, 95%) as an orange/red solid:
Rf 0.40 (hexanes/EtOAc 2.3:1); mp 235e240 ꢀC; IR (film) nmax 1734,
1252 nmax cmꢂ1; 1H NMR (CDCl3, 300 MHz)
d
0.95 (t, J¼7.5 Hz, 6H),
1.16 (t, J¼7.4 Hz, 6H), 1.30 (t, J¼7.1 Hz, 6H), 2.35 (q, J¼7.5 Hz, 4H),
2.72 (q, J¼7.4 Hz, 4H), 4.23 (m, 4H), 5.68 (s, 1H), 7.24 (d, J¼8.6 Hz,
2H), 8.16 (d, J¼8.6 Hz, 2H), 8.70 (br s, 2H); 13C NMR (CDCl3, 75 MHz)
d
14.7, 16.1, 16.3, 17.6, 18.8, 40.1, 60.4, 118.8, 124.2, 124.9, 129.4, 130.5,
134.2,147.4, 148.4, 162.1; MS (FAB) m/z 523 [Mþ.]; HRMS (FAB) calcd
for C29H37N3O6: [Mþ.] 523.2682, found [Mþ.] 523.2664. Anal. Calcd
for C29H37N3O6: C, 66.52; H, 7.12; N, 8.02. Found: C, 66.78; H, 7.25;
N, 8.09.
1528, 1350, 1231, 1168 cmꢂ1 1H NMR (CDCl3, 300 MHz)
; d 0.71 (t,
4.6. Bis(dipyrromethene) (9)
J¼7.5 Hz, 6H), 1.09 (t, J¼7.5 Hz, 6H), 1.45 (t, J¼7.1 Hz, 6H), 1.60 (q,
J¼7.5 Hz, 4H), 2.44 (q, J¼7.5 Hz, 4H), 4.49 (q, J¼7.1 Hz, 4H), 7.68 (d,
J¼8.7 Hz, 2H), 8.41 (d, J¼8.7 Hz, 2H); 13C NMR (CDCl3, 75 MHz)
To a solution of bis(dipyrromethane) 5 (79 mg, 64 mmol) in dry
CH2Cl2 (4 mL), DDQ (44 mg, 0.19 mmol) was added and the mixture
stirred at 20 ꢀC for 10 min under N2. The dark brown mixture was
diluted with CH2Cl2 (20 mL), washed with brine (3ꢁ15 mL), dried
(MgSO4), rotary evaporated, and chromatographed (hexanes/EtOAc
9:1e4:1) to give bis(dipyrromethene) 9 (77 mg, 98%) as an orange/
brown solid: Rf 0.40 (hexanes/EtOAc 2.3:1); mp 103 ꢀC; IR (film)
d
14.0, 15.1, 16.2, 17.3, 18.9, 62.2, 77.2, 123.5, 130.0, 131.5, 135.5, 140.7,
146.7, 147.6, 148.8, 162.1; 11B NMR (CDCl3, 125 MHz)
d
0.04 (t,
J¼27.7 Hz); 19F NMR (CDCl3, 235 MHz)
d
ꢂ145.8 (q, J¼27.7 Hz); MS
(FAB) m/z 569 [Mþ.]; HRMS (FAB) calcd for C29H34BF2N3O6: [Mþ.
]
569.2509, found [Mþ.] 569.2507. Crystal data for 12: C29H34BF2N3O6,
M¼569.4, monoclinic, P21/c (no. 14), a¼20.478(3), b¼17.580(2),
nmax 3289,1668,1240 cmꢂ1; 1H NMR (CDCl3, 300 MHz)
d 0.46 (br m,
12H), 1.10 (m, 12H), 1.90 (br m, 8H), 2.67 (br m, 8H), 5.37 (br m, 8H),
3
ꢀ
ꢂ3
ꢀ
ꢀ
c¼8.131(3) A,
b
¼100.99(2) , V¼2873(1) A , Z¼4, Dc¼1.316 g cm
,
m
(Cu K
a
)¼8.37 cmꢂ1, T¼193 K, orange platy needles; 4238 in-
dependent measured reflections, F2 refinement, R1¼0.107,
6.53 (s, 2H), 7.28 (d, J¼8.5 Hz, 2H), 7.34e7.60 (m, 20H), 7.88 (s, 2H),
8.27 (d, J¼8.5 Hz, 2H); 13C NMR (CDCl3, 75 MHz)
d 14.1, 16.0, 17.4,
wR2¼0.267, 3112 independent observed reflections [jFoj>4 (jFoj),
s
2
q
¼120ꢀ], 386 parameters. The high final value for R1 is a conse-
18.3, 66.1, 71.7, 115.8, 123.1, 126.6, 127.8, 128.0, 128.5, 135.1, 136.4,
137.8, 143.9, 162.2, 164.1; MS (FAB) m/z 1225 [Mþ.]; HRMS (FAB)
quence of the very poor quality of the crystalline sample, which
suffered from multiple twinning effects; the constitution and
structure of the compound is, however, unambiguous.
calcd for
C
78H77N6O8: [MþH]þ 1225.5803, found [MþH]þ
1125.5834. Anal. Calcd for C78H76N6O8: C, 76.45; H, 6.25; N, 6.86.
Found: C, 76.40; H, 6.35; N, 6.62.
4.10. Complexes 13 and 15
4.7. Bis(dipyrromethene) (10)
The same reaction as above with bis(dipyrromethene) 9 (16 mg,
mmol) and BF3$OEt2 (0.17 mL, 1.3 mmol), gave after chroma-
tography (hexanes/EtOAc 4:1e2.3:1) complex 13 (3 mg, 18%) as
a red solid: Rf 0.69 (hexanes/EtOAc 1:1); mp 103 ꢀC; IR (CHCl3) nmax
3440, 1702, 1536, 1231, 1167, 1126 cmꢂ1; 1H NMR (CDCl3, 300 MHz)
The same reaction as above with bis(dipyrromethane) 6 (92 mg,
mmol), gave after chromatography (hexanes/EtOAc 9:1e4:1)
13
94
bis(dipyrromethene) 10 (84 mg, 92%) as a pale pink solid: Rf 0.43
(hexanes/EtOAc 2.3:1); mp 170 ꢀC; IR (film) nmax 3288, 1666,
1243 cmꢂ1 1H NMR (CDCl3, 300 MHz)
; d 0.45 (br m, 12H), 1.12 (t,
d
0.53 (t, J¼7.4 Hz, 6H), 0.68 (t, J¼7.4 Hz, 6H), 0.96 (t, J¼7.4 Hz, 6H),
J¼7.1 Hz, 12H), 1.20 (m, 12H), 1.89 (br m, 8H), 2.65 (m, 8H), 4.32 (br
1.10 (t, J¼7.4 Hz, 6H), 1.31 (m, 2H), 1.61 (m, 2H), 2.12 (m, 4H), 2.37
(m, 4H), 2.70 (m, 4H), 5.21 and 5.27 (ABq, J¼12.5 Hz, 4H), 5.47 (s,
4H), 7.25e7.44 (m, 16H), 7.50e7.60 (m, 4H), 7.62 (d, J¼8.4 Hz, 1H),
7.80 (d, J¼8.2 Hz, 1H), 7.99 (s, 2H), 8.32 (d, J¼8.4 Hz, 1H), 8.43 (d,
m, 8H), 6.49 (s, 2H), 7.24 (d, J¼8.5 Hz, 2H), 7.85 (s, 2H), 8.23 (d,
J¼8.5 Hz, 2H); 13C NMR (CDCl3, 75 MHz)
d 14.0, 14.3, 15.8, 17.3, 18.2,
60.0, 71.7, 116.0, 123.0, 126.5, 127.7, 134.3, 134.7, 137.6, 143.9, 162.4,
164.2; MS (FAB) m/z 977 [Mþ.]; HRMS (FAB) calcd for C58H69N6O8:
[MþH]þ 977.5177, found [MþH]þ 977.5185. Anal. Calcd for
J¼8.2 Hz, 1H), 9.02 (s, 1H); 13C NMR (CDCl3, 75 MHz)
d 15.2, 15.4,
15.5, 17.3, 17.5, 18.3, 19.0, 65.7, 67.9, 74.6, 77.3, 117.0, 122.0, 124.1,
124.3, 127.0, 127.6, 128.0, 128.1, 128.3, 128.5, 128.6, 128.8, 132.8,
133.1, 135.3, 136.4, 136.5, 137.5, 143.9, 144.3, 145.2, 145.8, 147.9,
C
58H68N6O8: C, 71.29; H, 7.01; N, 8.60. Found: C, 71.35; H, 7.13; N,
8.75.
152.9, 160.8, 160.9, 162.1; 11B NMR (CDCl3, 125 MHz)
d
0.23 (t,
4.8. Dipyrromethene (11)
J¼28.0 Hz); 19F NMR (CDCl3, 235 MHz)
d
ꢂ142.7 (dq, J¼28.0 and
96.6 Hz), ꢂ148.7 (dq, J¼28.0 and 96.6 Hz); MS (FAB) m/z 1271
[Mꢂ2H]þ; HRMS (FAB) calcd for C78H75BF2N6O8: [Mþ.] 1272.5708,
found [Mþ.] 1272.5736, followed by 15 (9 mg, 52%) as a dark red
solid: Rf 0.56 (hexanes/EtOAc 1:1); mp 240 ꢀC; IR (CHCl3) nmax 1731,
Following the same procedure as for the preparation of 9,
dipyrromethane 8 (84 mg, 0.16 mmol) and DDQ (73 mg, 0.32 mmol)
gave after 16 h and chromatography (hexanes/EtOAc 9:1e4:1)
dipyrromethene 11 (75 mg, 90%) as a pale yellow solid: Rf 0.45
(hexanes/EtOAc 2.3:1); mp 174 ꢀC; IR (film) nmax 3431, 1685, 1524,
1536, 1226, 1170, 1128 cmꢂ1 1H NMR (CDCl3, 300 MHz)
; d 0.48 (t,
J¼7.4 Hz, 12H), 0.89 (t, J¼7.5 Hz, 12H), 1.25 (m, 4H), 1.39 (m, 4H),
2.29 (m, 8H), 5.42 (s, 8H), 7.29e7.40 (m, 12H), 7.47e7.57 (m, 8H),
7.88 (d, J¼8.2 Hz, 2H), 8.09 (s, 2H), 8.48 (d, J¼8.2 Hz, 2H); 13C NMR
1444,1351,1241 cmꢂ1; 1H NMR (CDCl3, 300 MHz)
d
0.78 (t, J¼7.5 Hz,
6H), 1.18 (t, J¼7.4 Hz, 6H), 1.34 (t, J¼7.1 Hz, 6H), 2.07e2.29 (m, 4H),
2.73 (q, J¼7.5 Hz, 4H), 4.28 (q, J¼7.1 Hz, 4H), 7.59 (d, J¼8.8 Hz, 2H),
(CDCl3, 75 MHz) d 15.5, 16.0, 17.6, 19.1, 68.2, 77.6, 125.0, 128.3, 128.6,
8.22 (d, J¼8.8 Hz, 2H), 8.83 (s, 1H); 13C NMR (CDCl3, 75 MHz)
d
14.3,
128.8, 129.1, 129.4, 133.1, 135.6, 136.8, 145.3, 145.4, 146.2, 147.8,
15.2, 15.7, 17.6, 18.3, 60.2, 74.9, 117.6, 123.5, 123.9, 128.5, 132.3, 135.2,
153.9, 162.3; 11B NMR (CDCl3, 125 MHz)
d
0.09 (t, J¼27.8 Hz); 19F
147.6, 150.2, 161.6; MS (FAB) m/z 522 [Mþ.]; HRMS (FAB) calcd for
NMR (CDCl3, 235 MHz)
d
ꢂ141.6 (dq, J¼27.8 and 95.6 Hz), ꢂ150.1
C
29H36N3O6: [MþH]þ 522.2604, found [MþH]þ 522.2587. Anal.
(dq, J¼27.8 and 95.6 Hz); MS (FAB) m/z 1321 [Mþ.], 1243 [MꢂPh]þ;