1.1 Porphyrins - Friedrich-Alexander-Universität Erlangen-Nürnberg

6 Experimental Section
6.2.6 AB2C-Type Mono-Exocyclic Cycloketo-Porphyrins, Precursors &
178
Derivatives
6.2.6.1 αβ-5 2 -(Bromomethyl)-5 4 ,10 4 ,15 4 ,20 4 -Tetra-t-Butyl-15 2 -(Methoxymethyl)-5 6 ,15 6 -
Br
Dimethyl-5,10,15,20-Tetraphenylporphyrin, 82
In a 100 mL round bottom flask, 302 mg (316 μmol) of
methoxymethyl porphyrin 42 are dissolved in CH2Cl2 (50 mL).
Upon addition of 15 mL of HBr (5.4 M in glacial HOAc), the
mixture turns green immediately and the flask is closed by a
one-hole stopper with exhaust duct. After 3 h of stirring at rt,
the green solution is transferred into a separatory funnel and
repeatedly washed with water until the color changes to
purple. Then, the organic layer is neutralized by shaking with
a saturated aqueous solution of NaHCO3, washed with water
and dried over MgSO4. Pure 82 is obtained after FC (silica, CH2Cl2 : hexanes = 3 : 1) as purple
powder in 82.6 mg (82.3 μmol) yield, equiv. to 26 % based on 42.
1 H NMR (400 MHz, rt, CDCl3): δ [ppm] = -2.62 (s, 2 H, NH), 1.57 (s, 18 H, t-BuH), 1.59 (s, 9 H,
t-BuH), 1.60 (s, 9 H, t-BuH), 1.84 (s, 3 H, CH3), 1.85 (s, 3 H, CH3), 2.77 (s, 3 H, OCH3), 3.95 (s,
2 H, CH2OCH3), 4.11 (s, 2 H, CH2Br), 7.52 (s, 1 H, Ar’H), 7.54 (s, 1 H, Ar’H), 7.73 (m, 4 H, ArH),
7.75 (s, 1 H, Ar’H), 7.78 (s, 1 H, Ar’H), 8.14 (m, 4 H, ArH), 8.63 (d, 3 J = 4.7 Hz, 4 H, β-H), 8.85
(d, 3 J = 4.9 Hz, 4 H, β-H).
13 C NMR (100.5 MHz, rt, CDCl3): δ [ppm] = 21.5, 21.6, 31.4, 31.5, 31.6, 33.0, 34.7 (two
signals), 34.8, 57.9, 73.2, 116.2, 116.7, 119.8, 120.7, 123.6 (two signals), 124.5, 125.2, 126.5,
130-132 (br), 134.4, 134.5, 136.8, 138.8, 138.4, 138.5, 139.1, 139.4, 150.5, 151.4, 151.9.
MS (FAB+, NBA): m/z (%) = 1004 (100) [M] +· , 925 (17) [M-Br] +· .
IR (ATR): 𝜈� [cm -1 ] = 3309, 3030, 2963, 2903, 2868, 1560, 1506, 1476, 1396, 1362, 1349, 1269,
1222, 1188, 1109, 1025, 993, 983, 968, 913, 875, 849, 824, 800, 740.
UV/Vis (CH2Cl2): λ [nm] (ε [M -1 ·cm -1 ]) = 421 (398000), 517 (22100), 551 (9900), 593 (7500),
647 (5700).
N
NH HN
N
C65H71BrN4O M = 1004.19 g·mol-1 O
82