1.1 Porphyrins - Friedrich-Alexander-Universität Erlangen-Nürnberg

6 Experimental Section
6.2.4.9 10 4 , 15 4 , 20 4 - Tri - t - Butyl - 5 , 10 , 15 , 20 - Tetraphenylporphyrin - 5 2 - Methyl
MeO 2 C
154
Methanoate, 60
In a 2 L round bottom flask, methyl 2-formylbenzoate 59
(1.64 g, 10 mmol), 4-t-butylbenzaldehyde (5.0 mL, 30 mmol)
and pyrrole (2.8 mL, 40 mmol) are dissolved in CHCl3 (1 L).
BF3·OEt2 (0.5 mL, 4.1 mmol) is added and the solution is
stirred at rt for 70 min under exclusion of light whereupon
the color changes slowly to dark purple. Then DDQ (4.5 g,
20 mmol) is added and stirring is continued for further 2 h.
The crude product is gained by removal of the solvents and
pre-cleaning via filtration over a silica plug with CH2Cl2 as
eluent. Final purification is achieved by FC over silica eluting with CH2Cl2 and hexanes (ratio
2 : 3). Yield: 1.46 g (174 µmol) of 60 as purple powder, equiv. to 17.4% based on 59.
1 H NMR (400 MHz, rt, CDCl3): δ [ppm] = -2.67 (s, 2 H, NH), 1.61 (s, 18 H, t-Bu-H), 1.62 (s, 9 H,
t-Bu-H), 2.72 (s, 3 H, CH3), 7.76 (m, 7 H, ArH & Ar’H), 7.82 (dd, 3 J = 7.3 Hz, 4 J = 1.7 Hz, 1 H,
Ar’H), 7.86 (dt, 3 J = 7.8 Hz, 4 J = 1.5 Hz, 1 H, Ar’H), 8.15 (m, 6 H, ArH), 8.40 (dd, 3 J = 7.7 Hz,
4 J = 1.6 Hz, Ar’H), 8.66 (d, 3 J = 4.8 Hz, 2 H, β-H), 8.87 (d, 3 J = 4.8 Hz, 2 H, β-H), 8.89 (s, 4 H, β-
H).
13 C NMR (100.5 MHz, rt, CDCl3): δ [ppm] = 31.6, 34.8, 51.5, 118.7, 120.2, 120.3, 123.6, 128.3,
129.6, 129.7, 134.2, 134.5, 136.1, 139.2, 142.7, 150.5, 168.2.
MS (FAB+, NBA): m/z (%) = 841 (100) [MH] +· .
IR (ATR): 𝜈� [cm -1 ] = 3319, 3028, 2961, 2902, 2867, 1735, 1720, 1473, 1398, 1362, 1349, 1291,
1257, 1108, 1084, 968, 801, 734.
UV/Vis (CH2Cl2): λ [nm] (ε [M -1 ·cm -1 ]) = 419 (267400), 516 (9900), 552 (5600), 592 (3200), 649
(2400).
N
NH HN
N
60
C 58 H 56 N 4 O 2
M = 841.09 g·mol -1
EA: C58H56N4O2·0.5 H2O. Calc.: C 81.95, H 6.76, N 6.59; found: C 81.81, H 6.86, N 6.43.