Dalton Transactions
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C6H4(SiiPr2H)2 (3). The preparation is similar to that of 1. 1161(w), 1129(s), 1064(m), 989(s), 920(w), 880(s), 817(s), 780
(1,4-dibromobenzene: 35.0 g, 0.15 mol, 1.1eq.; Mg: 6.56 g, (vs), 739(w), 723(w), 650(s), 622(vs), 546(m), 517(s), 499(s);
0.27 mol, 2eq.; HSiiPrCl: 40.7 g, 0.27 mol, 2eq.). Distillative elemental analysis [%] calcd: N 8.32, C 64.22, H 10.78, found:
purification: 1 × 10−3 mbar, 65 °C. Yield: 90% (37.2 g, N 7.62, C 63.51, H 10.498; MS (+p APCI): m/z [%] calcd:
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0.12 mol) in the form of a colourless oil. H NMR (300 MHz, 361.2466, found: 361.2490 [MNa]+ (100).
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C6D6): δ = 0.96–1.24 (m, 28H, HiPr), 4.19 (t, JHH = 3.0 Hz, 2H,
C6H4(SiiPr2OH)2 (7). To a stirred solution of 0.80 g
SiH), 7.57 ppm (s, 4H, Har); 13C{1H} NMR (C6D6): δ = 11.1 (s, (2.4 mmol, 1eq.) of C6H4(SiiPr2NH2)2 in 50 mL diethylether
CH(CH3)2), 18.8 (s, CH(CH3)2), 18.9 (s, CH(CH3)2), 135.2 (s, was added 0.20 mL (9.5 mmol, 4eq.) of H2O. The reaction
Car), 135.5 ppm (s, Car); 29Si{1H} NMR (60 MHz, C6D6): δ = mixture was stirred for 18 h, followed by removal of the
5.7 ppm (s); IR [cm−1] 2943(w), 2893(w), 2863(w), 2101(m), aqueous phase. The solvent was removed and 86% (0.71 g,
1461(w), 1377(w), 1238(w), 1132(w), 1070(w), 1000(w), 919(w), 2.0 mmol) of 7 was obtained in the form of a colourless
880(w), 777(s), 729(w), 657(m), 618(w), 511(m), 455(w), 413(w); powder. 7 was recrystallized from diethylether at −35 °C within
MS (EI): m/z [%] calcd: 306.22, found: 306.2199 [M]+ (100).
4 d. 1H NMR (300 MHz, C6D6): δ = 0.89 (d, 7.3 Hz, 12H, CH
C6H4(SiiPr2Cl)2 (4). The preparation is similar to that of 2. (CH3)2), 10.96(d, 7.2 Hz, 12H, CH(CH3)2), 1.08–1.18 (m, 4H,
(3: 37.2 g, 0.12 mol, 3eq.; TCCA: 18.8 g, 0.81 mol, 2 eq.). Yield: CH(CH3)2), 7.44 ppm (s, 4H, Har); 13C{1H} NMR (75 MHz,
98% (44.6 g, 0.12 mol) in the form of colourless crystals. 1H C6D6): δ = 13.0 (s, CH(CH3)2), 17.2 (s, CH(CH3)2), 17.5 (s, CH
NMR (300 MHz, C6D6): δ = 0.89–1.07 (m, 24H, CH(CH3)2), (CH3)2), 133.7 (s, Car), 136.1 ppm (s, Car); 29Si{1H} NMR
1.31–1.14 (m, 4H, CH(CH3)2), 7.64 ppm (s, 4H, Har); 13C{1H} (60 MHz, C6D6): δ = 7.1 ppm (s); IR [cm−1]: 3299(w, O-H),
NMR (75 MHz, C6D6): δ = 14.1 (s, CH(CH3)2), 16.9 (s, CH 2941(m), 2863(m), 1462(m), 1382(w), 1367(w), 1242(w),
(CH3)2), 17.2 (s, CH(CH3)2), 133.6 (s, Car), 134.5 ppm (s, CH3); 1135(m), 1064(m), 992(w), 920(w), 881(s), 817(vs), 801(vs),
29Si{1H} NMR (60 MHz, C6D6): δ = 27.1 ppm (s); IR [cm−1]: 748(w), 670(vs), 628(vs), 603(s), 523(vs), 502(s), 445(w), 420(w);
2949(s), 2867(m), 2848(m), 1461(m), 1385(w), 1366(w), 1260(w), elemental analysis [%] calcd: C 63.84, H 10.12, found: C 64.58,
1240(w), 1131(s), 1064(m), 989(s), 923(w), 878(s), 807(s), H 10.354; MS (ESI−): m/z [%] calcd: 337.2025, found: 337.2014
739(w), 699(w), 671(s), 648(vs), 555(vs), 517(vs), 444(s); CHN [M]− − H (100).
[%] calcd: C 57.57, H 8.59, found: C 57.58, H 8.466; MS (EI):
m/z [%] calcd: 374.14196, found: 374.14002[M] (7).
C6H4(SiMe2PH2)2 (8). At −50 °C, 10.5 g (39.9 mmol, 2eq.) of
2 in 100 mL of dimethoxyethane (DME) was slowly added to a
stirred solution of 60 mL (24.0 mmol, 0.4 M in DME, 1.1eq.) of
[C6H4(SiMe2NH)2]2 (5).
A stirred solution of 6.54 g
(24.8 mmol, 1eq.) of 2 in 100 mL of toluene was purged with [LiAl(PH2)4]. The resulting suspension was allowed to warm to
ammonia for 3.5 h. The completion of the reaction was con- ambient temperature and was stirred for additional 14 h.
trolled via a 29Si{1H} NMR experiment of the solution using a Subsequently, the solvent was removed under reduced
glass capillary with D2O as the standard. The white precipitate pressure, and the residue was suspended in 150 mL of
was separated by filtration, and the solvent was removed n-pentane. The suspension was filtered, and the white precipi-
in vacuo. The raw product was purified by recrystallization tate was washed two times with 50 mL of n-pentane. The
from toluene and dichloromethane (2 : 1) at −25 °C within 4 solvent of the filtrate was removed under reduced pressure,
d. 74% (3.8 g, 9.2 mmol) of 5 was obtained in the form of col- and 97% (10.0 g, 38.8 mmol) of the pure product was obtained
ourless plates. 1H NMR (300 MHz, C6D6): δ = 0.34 (s, 24H, in the form of a colourless solid. 8 was recrystallized at 6 °C
CH3), 0.50 (s, 2H, NH2), 7.68 ppm (s, 8H, C6H4); 13C{1H} NMR from benzene and yielded colourless blocks within 2 d.
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(75 MHz, C6D6): δ = 1.4 (s, CH3), 131.2 (s, Car), 133.2 (s, Car),
1H NMR (300 MHz, C6D6): δ = 0.38 (d, JPH = 3.8 Hz, 12H,
135.4 (s, Car), 142.3 ppm (s, Car); 29Si{1H} NMR (60 MHz, CH3), 1.42 (d, JPH = 183.7 Hz, 4H, PH2), 7.48 ppm (s, 4H,
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C6D6): δ = −3.9 ppm (s); IR [cm−1]: 3342(w, N-H), 3040(w), C6H4); 13C{1H} NMR (75 MHz, C6D6): δ = 1.38 (d, JPC = 9.1 Hz,
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2952(w), 1377(w), 1246(m), 1190(m), 1129(s), 930(s), 849(m), CH3), 132.00 (s, Car), 133.76 ppm (d, JPC = 2.16, Car); 29Si{1H}
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821(s), 782(vs), 661(s), 603(m), 496(s), 4412(w); elemental ana- NMR (75 MHz, C6D6): δ = −1.40 ppm (d, 1JPSi = 17.6 Hz); 31P{H}
lysis [%] calcd: N 6.75, C 57.91, H 8.26, found: N 6.01, C 56.19, NMR (102 MHz, C6D6): δ = −237.46 ppm (s); 31P NMR
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H 7.900; MS (+p APCI): m/z [%] calcd: 414.1870 [MH]+, found: (102 MHz, C6D6): δ = −237.45 ppm (t, JPH = 183.7 Hz);
414.1872 [MH]+ (70).
IR [cm−1]: 3043(vw), 2952(w), 2287(m, P-H), 1569(vw), 1404(w),
C6H4(SiiPr2NH2)2 (6). The preparation is similar to that of 5. 1375(m), 1246(s), 1127(s), 1052(m), 1012(m), 834(s), 775(vs),
(4: 3.26 g, 8.7 mmol). 86% (2.5 g, 7.5 mmol) yield was obtained 648(s), 616(m), 486(vs), 446(m), 410(vw); elemental analysis
after recrystallization from toluene and dichloromethane [%] calcd: C 46.48, H 7.80, found: C 46.330, H 7.829; MS
within 2 d at −25 °C in the form of colourless blocks. 1H NMR (+p APCI): m/z [%] calcd: 258.06, found: 259.0667 [MH]+ (100).
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(300 MHz, C6D6): δ = 0.20 (s, 4H, NH2), 0.97 (d, JHH = 6.5 Hz,
C6H4(SiiPr2PH2)2 (9). At −25 °C, PH3 was slowly passed into
12H, CH3), 1.03 (d, 3JHH = 6.3 Hz, 12H, CH3), 1.00–1.16 (m, 4H, a solution of 7.0 g (18.72 mmol, 1eq.) of 4 and 300 mL of Et2O.
iPr), 7.68 ppm (s, 4H, Har); 13C{1H} NMR (75 MHz, C6D6): δ = After 10 min, 14.98 mL (37.44 mmol, 2eq., 2.5 M in hexane) of
H
12.4 (s, CH(CH3)2), 17.6 (s, CH(CH3)2), 17.8 (s, CH(CH3)2), n-BuLi in 100 mL of n-heptane was slowly dropped into the
134.0 (s, Car), 137.9 ppm (s, Car); 29Si{1H} NMR (60 MHz, stirred solution under continuous flow of PH3. After complete
C6D6): δ = 0.0 (s); IR [cm−1]: 3376(w, N-H), 3043(w), 2948(m), addition of n-BuLi, the PH3 flow was maintained for an
2891(w), 2862(s), 1546(m), 1460(m), 1382(w), 1365(w), 1236(m), additional 10 min. Subsequently, the reaction vessel was
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Dalton Trans.