Organometallics
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(377 MHz, d8-THF, 298 K): δ −127.0 (br, 1F, C6F4), −127.3 (m, 1F, p-
C6F4), −127.7 (br, 1F, C6F4), −131.5 (m, 2F, o-BC6F5), −133.6 (m, 1F,
C6F4), −138.7 (m, 1F, o-CC6F5), −142.2 (m, 1F, o-CC6F5), −163.3
(t, 1F, JF−F = 20.3 Hz, p-BC6F5), −163.5 (t, 1F, JF−F = 20.7 Hz, p-
CC6F5), −166.8 (m, 1F, m-CC6F5), −167.6 to −167.7 (m, 3F, m-BC6F5,
m-CC6F5), −193.0 (br, 1F, BF). 31P{1H} NMR (162 MHz, CD2Cl2, 298
CD2Cl2, 298 K): δ 11.0 (br s). 11B NMR (128 MHz, CD2Cl2, 298K):δ 0.48
(br, BF). 13C{1H} NMR (101 MHz, d8-THF, 298 K) partial: δ 149.6
(Ph2C), 148.4 (dm, 1JC−F = 247 Hz, CF), 148.0 (dm, 1JC−F = 247 Hz,
CF), 146.1 (i-Ph), 145.6 (dm, 1JC−F = 252 Hz, CF), 145.4 (dm, 1JC−F
=
3
3
252 Hz, CF), 143.8 (ipso-Ph), 143.4 (dm, 1JC−F = 247 Hz, CF), 137.7
1
1
(dm, JC−F = 247 Hz, CF), 136.2 (dm, JC−F = 250 Hz, CF), 129.7
(o-Ph), 128.0 (o-Ph), 127.1 (m-Ph), 126.2 (m-Ph), 125.7 (p-Ph), 125.4
(p-Ph), 123.9 (tm, 2JC−F = 20.8 Hz, i-CC6F5), 87.5 (br, ipso-PC6F4), 28.6
K): δ 33.4 (br). 11B NMR (128 MHz, CD2Cl2, 298 K): δ 1.49 (d, 1JB−F
=
50.8 Hz, BF). 13C{1H} NMR (101 MHz, d8-THF, 298 K) partial: δ
148.9 (dm, 1JC−F = 244 Hz, CF), 148.4 (dm, 1JC−F = 244 Hz, CF), 145.0
(dm, 1JC−F = 248 Hz, CF), 143.7 (dm, 1JC−F = 249 Hz, CF), 142.8 (dm,
1JC−F = 240 Hz, CF), 139.5 (ipso-Ph), 138.0 (dm, 1JC−F = 247 Hz, CF),
137.0 (dm, 1JC−F = 247 Hz, CF), 136.6 (dm, 1JC−F = 246 Hz, CF), 136.3
(d, 1JC−P = 41.7 Hz, P-Cy), 26.3 (d, 2JC−P = 3.3 Hz, Cy), 25.5 (d, 3JC−P
=
15.6 Hz, Cy), 24.8 (Cy).
Synthesis of [tBu3PH][CH3(CH2)3CH(C6F5)BH(C6F5)2], 9a. A
solution of 4a (58 mg, 0.1 mmol) and tBu3P (20 mg, 0.1 mmol) in
toluene (2 mL) was degassed, and the reaction flask filled with H2 (2.5
bar). The reaction mixture was stirred overnight under H2 (2.5 bar), and
pentane (10 mL) was added, after which the supernatant was decanted.
Crystallizing the residue with CH2Cl2/pentane (v/v = 1:3, 4 mL)
at −35 °C and then drying in vacuo afforded 9a as a white powder (68 mg,
87%). Crystals suitable for X-ray crystal structure analysis were grown by
a CH2Cl2/pentane (v/v = 1:3) solution of 9a at −35 °C. Anal. Calcd for
1
(dm, JC−F = 247 Hz, CF), 134.8 (C(H)), 127.6 (o,m-Ph), 125.9
(p-Ph), 123.8 (br, i-BC6F5), 120.5 (tm, 2JC−F = 22.8 Hz, i-CC6F5), 90.1
(dtm, 1JC−P = 70.0 Hz, 2JC−F = 19.3 Hz, ipso-PC6F4), 35.5 (d, 1JC−P = 31.6
Hz, tBu), 26.6 (tBu).
7e: 50 °C, 48 h, 99% yield. Anal. Calcd (%) for C32H29BF15P: C 52.19,
H 3.95. Found: C 52.56, H 4.41. 1H NMR (400 MHz, CD2Cl2, 298 K): δ
1
6.33 (d, 1H, JH−P = 466 Hz, PH), 2.25 (m, 2H, CH2), 1.90 (m, 2H,
1
CH2), 1.59 (d, 18H, 3JH−P = 19.0 Hz, tBu), 0.88 (t, 3H, 3JH−H = 7.4 Hz,
CH3), 0.72 (t, 3H, 3JH−H = 7.4 Hz, CH3). 19F NMR (377 MHz, CD2Cl2,
298 K): δ −125.6 (br, 1F, C6F4), −126.2 (br, 1F, C6F4), −126.5 (m, 1F,
p-C6F4), −133.0 (m, 3F, o-BC6F5, C6F4), −139.4 (m, 1F, o-CC6F5),
C35H39BF15P: C, 53.45; H, 5.00. Found: C, 53.31; H, 5.10. H NMR
(600 MHz, CD2Cl2, 298 K): δ 5.29 (d, 1JPH = 433.5 Hz, 1H, PH), 3.23
(br t, 3JHH = 10.1 Hz, 1H, BCH), 2.94 (1:1:1:1 q, 1JBH ≈ 95 Hz, BH),
3
1.88/1.64 (each m, each 1H, CHCH2), 1.67 (d, JPH = 15.7 Hz, 27H,
tBu), 1.27/1.20 (each m, each 1H, MeCH2), 1.12 (m, 2H, CH2), 0.80
(t, 3JHH = 7.3 Hz, 3H, CH3). 13C{1H} NMR (151 MHz, CD2Cl2, 298 K):
3
−140.3 (br, 1F, o-CC6F5), −162.4 (t, 1F, JF−F = 20.8 Hz, p-C6F5),
3
−163.6 (t, 1F, JF−F = 20.8 Hz, p-C6F5), −166.7 to 166.9 (m, 4F, m-
1
δ 38.0 (d, JPC = 27.1 Hz, tBu), 33.5 (CH2), 33.0 (CHCH2), 30.3 (d,
BC6F5, m-CC6F5), −184.5 (br, 1F, BF). 31P{1H} NMR (162 MHz,
CD2Cl2, 298 K): δ 33.1 (br). 11B NMR (128 MHz, CD2Cl2, 298 K): δ
0.39 (d, JB−F = 40.8 Hz, BF). 13C{1H} NMR (101 MHz, CD2Cl2, 298 K)
partial: δ 150.6 (Et2C), 149.3 (dm, 1JC−F = 252 Hz, CF), 142.0 (dm,
2JPC = 5.9 Hz, tBu), 30.3 (br, BCH), 23.2 (MeCH2), 14.4 (CH3), [C6F5
not listed]. 19F NMR (564 MHz, CD2Cl2, 298 K): δ −132.6 (m, 4F),
−140.9 (br, 1F), −143.7 (br, 1F) (o-C6F5), −164.6 (t, 3JFF = 20.3 Hz),
−164.9 (t, 3JFF = 20.3 Hz), −166.2 (t, 3JFF = 21.3 Hz) (each 1F, p-C6F5),
−167.3 (m, 4F), −167.5 (m, 2F) (m-C6F5). 11B{1H} NMR (192 MHz,
CD2Cl2, 298 K): δ −19.3 (ν1/2 ≈ 60 Hz). 11B NMR (192 MHz, CD2Cl2,
298 K): δ −19.3 (d, 1JBH = 90.6 Hz). 31P{1H} NMR (202 MHz, CD2Cl2,
298 K): δ 59.2 (ν1/2 ≈ 3 Hz). 31P NMR (202 MHz, CD2Cl2, 298 K): δ
59.2 (dm, 1JPH ≈ 433 Hz). X-ray data: a = 9.9252(3) Å, b = 20.0004(11)
Å, c = 18.3802(7) Å, β = 93.002(3)°, V = 3643.6(3) Å3, Z = 4,
monoclinic, space group P21/n, 4875 observed reflections (I ≥ 2σ(I)),
490 refined parameters, R1 = 0.0889, wR2(all) = 0.2672, GOF = 1.067.
Synthesis of [tBu3PH][CH3(CH2)4CH(C6F5)BH(C6F5)2], 9b. A
similar procedure to that mentioned above for the preparation of
compound 9a was carried out by using starting material 4b to yield 9b as
a white powder (66 mg, 82%). Anal. Calcd for C36H41BF15P: C, 54.02;
H, 5.16. Found: C, 53.86; H, 5.25. 1H NMR (500 MHz, CD2Cl2, 298 K):
1JC−F = 240 Hz, CF), 143.7 (dm, 1JC−F = 240 Hz, CF), 138.5 (dm, 1JC−F
=
249 Hz, CF), 137.6 (dm, 1JC−F = 252 Hz, CF), 136.7 (dm, 1JC−F = 246
Hz, CF), 131.6 (br, CB), 123.9 (br, i-BC6F5), 122.6 (tm, 2JC−F = 22.0
Hz, ipso-CC6F5), 88.7 (m, ipso-PC6F4), 36.0 (d, 1JC−P = 30.9 Hz, tBu),
27.6 (tBu), 26.2 (CH2), 25.9 (CH2), 12.0 (CH3), 11.8 (CH3).
7g: 70 °C for 48 h, 42% yield off-white solid. Anal. Calcd (%) for
C40H29BF15P: C 57.44, H 3.49. Found: C 57.19, H 3.70. 1H NMR (400
MHz, CD2Cl2, 298 K): δ 7.40 (d, 2H, 3JH−H = 7.0 Hz, o-Ph), 7.30 (m,
1H, p-Ph), 7.13 (m, 4H, o,m-Ph), 7.02 (t, 2H, 3JH−H = 7.0 Hz, m-Ph),
1
6.95 (m, 1H, p-Ph), 6.27 (d, 1H, JH−P = 465 Hz, PH), 1.57 (d, 18H,
3JH−P = 19.2 Hz, tBu). 19F NMR (377 MHz, CD2Cl2, 298 K): δ −124.2
(br, 1F, C6F4), −124.5 (br, 1F, C6F4), −127.1 (m, 1F, p-C6F4), −132.4
(m, 2F, o-BC6F5), −133.5 (m, 1F, C6F4), −138.3 (m, 1F, o-CC6F5),
3
1
3
−139.0 (m, 1F, o-CC6F5), −161.9 (t, 1F, JF−F = 20.4 Hz, p-BC6F5),
δ 5.31 (d, JPH = 433.8 Hz, 1H, PH), 3.23 (br t, JHH = 10.1 Hz, 1H,
BCH), 2.93 (br, BH), 1.88/1.64 (each m, each 1H, CHCH2)1, 1.68 (d,
3JPH = 15.7 Hz, 27H, tBu), 1.21/1.18 (each m, each 1H, MeCH2)1, 1.23/
1.18 (each m, each 1H, 4-CH2)1, 1.14 (m, 2H, 3-CH2)1, 0.81 (m, 3H,
CH3) [1 from ghsqc experiment]. 13C{1H} NMR (126 MHz, CD2Cl2,
298 K): δ 38.0 (d, 1JPC = 27.1 Hz, tBu), 33.3 (CHCH2), 32.5 (C4), 30.9
(C3), 30.3 (tBu), 30.2 (br, B-CH), 23.2 (MeCH2), 14.3 (CH3) [C6F5 not
listed]. 19F NMR (470 MHz, CD2Cl2, 298 K): δ −132.6 (m, 4F), −140.9
(br, 1F), −143.7 (br, 1F) (o-C6F5), −164.6 (t, 3JFF = 20.3 Hz), −164.9
(t, 3JFF = 20.3 Hz), −166.2 (t, 3JFF = 21.3 Hz) (each 1F, p-C6F5), −167.3
(m, 4F), −167.5 (m, 2F) (m-C6F5). 11B{1H} NMR (160 MHz, CD2Cl2,
298 K): δ −19.3 (ν1/2 ≈ 70 Hz). 11B NMR (160 MHz, CD2Cl2, 298 K):
δ −19.3 (d, 1JBH = 93.1 Hz). 31P{1H} NMR (202 MHz, CD2Cl2, 298 K):
δ 59.1 (ν1/2 ≈ 3 Hz). 31P NMR (202 MHz, CD2Cl2, 298 K): δ 59.1 (dm,
1JPH = 433.9 Hz).
3
−162.2 (t, 1F, JF−F = 20.4 Hz, p-CC6F5), −166.6 (m, 1F, m-CC6F5),
−166.8 (m, 1F, m-CC6F5), −166.9 (m, 2F, m-BC6F5), −179.0 (br, 1F,
BF). 31P{1H} NMR (162 MHz, CD2Cl2, 298 K): δ 33.1 (br). 11B NMR
(128 MHz, CD2Cl2, 298 K): δ 0.68 (d, 1JB−F = 52.3 Hz, BF). 13C{1H}
NMR (101 MHz, CD2Cl2, 298 K): δ partial: 149.8 (Ph2C), 148.9
(dm, 1JC−F = 251 Hz, CF), 148.2 (dm, 1JC−F = 247 Hz, CF), 145.9 (dm,
1JC−F = 244 Hz, CF), 146.3 (i-Ph), 144.3 (ipso-Ph), 143.8 (dm, 1JC−F
=
244 Hz, CF), 138.1 (dm, 1JC−F = 249 Hz, CF), 136.7 (dm, 1JC−F = 244
Hz, CF), 129.9 (o-Ph), 128.3 (m-Ph), 127.9 (o-Ph), 127.0 (m-Ph), 126.4
(p-Ph), 126.2 (p-Ph), 123.6 (br, ipso-BC6F5), 123.5 (tm, 2JC−F = 21.2 Hz,
ipso-CC6F5), 89.1 (dtm, 1JC−P = 73.6 Hz, 2JC−F = 17.8 Hz, i-PC6F4), 36.1
(d, 1JC−P = 31.3 Hz, tBu), 36.0 (d, 1JC−P = 31.3 Hz, tBu), 27.7 (tBu), 27.6
(tBu). X-ray data: a = 9.8745(6) Å, b = 18.2413(10) Å, c = 23.7744(13)
Å, V = 4282.3(4) Å3, Z = 4, orthorhombic, space group P212121, 9855
observed reflections (I ≥ 2σ(I)), 565 refined parameters, R1 = 0.0728,
wR2(all) = 0.2161, GOF = 1.037. 8g: 70 °C for 24 h, 64% yield. Anal.
Calcd (%) for C44H33BF15P: C 59.48, H 3.74. Found: C 59.51, H 3.98.
1H NMR (400 MHz, d8-THF, 298 K): δ 7.41 (d, 2H, 3JH−H = 7.5 Hz,
o-Ph), 7.13 (d, 2H, 3JH−H = 7.6 Hz, o-Ph), 7.06 (t, 2H, 3JH−H = 7.6 Hz,
m-Ph), 7.03 (d, 1H, 1JH−P = 496 Hz, PH), 7.00−6.89 (m, 2H, p-Ph, p-Ph),
Synthesis of [tBu3PH][PhCH2CH(C6F5)BH(C6F5)2], 9c. In a
glovebox, a 50 mL glass tube equipped with a small stir bar and a
Teflon screw top was charged with a solution of (E)- and (Z)-4c (30:1)
(77 mg, 0.12 mmol) and tBu3P (25 mg, 0.12 mmol) in toluene (1 mL).
The yellow solution was degassed three times through a freeze−pump−
thaw cycle on the vacuum/H2 line and filled with H2 (4 bar) at −196 °C.
After the addition of H2 the reaction tube was allowed to mix at 80 °C for
15 h. The product was precipitated from solution by adding pentane
(20 mL) dropwise. The crude product was dried under vacuum and
shown to be a mixture of 5c, 9c, and 10c in a 4:9:2 ratio. Crystals of 9c
suitable for X-ray diffraction were grown from a layered C6D5Br/hexane
solution at 25 °C and isolated in ca. 30% yield. Anal. Calcd (%) for
3
6.97 (t, 2H, JH−H = 7.5 Hz, m-Ph), 3.00 (br, 2H, Cy), 2.17 − 1.34
(br m, 20H, Cy). 19F NMR (377 MHz, d8-THF, 298 K): δ −124.5 (br, 2F,
C6F4), −132.3 (br, 2F, o-BC6F5), −132.9 (br d, 2F, C6F4), −138.4 (m, 1F,
3
o-CC6F4), −139.0 (br, 1F, o-CC6F4), −162.0 (t, 1F, JF−F = 20.2 Hz,
p-C6F5), −162.3 (t, 1F, 3JF−F = 21.5 Hz, p-C6F5), −166.8 to −167.0 (m,
4F, m-BC6F5, m-CC6F5), −179.8 (br, 1F, BF). 31P{1H} NMR (162 MHz,
5645
dx.doi.org/10.1021/om3006068 | Organometallics 2012, 31, 5638−5649