Job/Unit: O20176
/KAP1
Date: 19-04-12 14:59:44
Pages: 11
Intermediate (Aryne)chromium Complexes
product was purified by column chromatography (30ϫ3 cm, SiO2,
CO), 1480 (w), 1416 (m), 1218 (m), 1125 (m), 1090 (w), 995 (w),
PE/TBME 7:3). Compound 13 (5.8 g, 13.8 mmol, 99%) was iso-
870 (w) cm–1. MS (70 eV): m/z (%) = 596 (10) [M]+, 568 (5) [M –
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lated as a yellow oil. H NMR (400.1 MHz, CDCl3): δ = 3.69 (s, 3 CO]+, 540 (25) [M – 2 CO]+, 314 (90) [CrPPh3]+, 263 (100)
H, 5-OCH3), 3.78 (s, 3 H, 2-OCH3), 4.94 (d, J = 5.3 Hz, 1 H, 6-
H), 5.39–5.44 [m, 2 H, 3-H, 4-H] ppm. 13C NMR (400.1 MHz,
CDCl3): δ = 56.6 (5-OCH3), 58.4 (2-OCH3), 73.4 (C-6), 74.1 (C-4),
[PPh3]+. HRMS: calcd. for C27H20CrF3O5PS 596.0126; found
596.0124. C27H20CrF3O5PS (596.48): calcd. C 54.37, H 3.38; found
C 54.33, H 3.41.
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Dicarbonyl(η6-4-methoxyphenyl triflate)(triphenylphosphane)chrom-
ium(0) (19): Triphenylphosphane (6.1 g, 23.1 mmol) was added to
a solution of tricarbonyl(4-methoxyphenyl triflate)chromium(0)[36]
(17, 3.0 g, 7.7 mmol) in toluene. The reaction mixture was irradi-
ated (125 W mercury lamp, quartz filter) for 25 min in a photo-
chemical immersion cell fitted with a reflux condenser, which was
cooled with water. The reaction mixture was continuously flushed
with argon. The reaction progress was monitored by TLC. After
the complete consumption of the starting material (ca. 25 min), the
reaction mixture was irradiated for a further 20 min. The solvent
was removed at reduced pressure, and the crude product was puri-
fied by column chromatography (30ϫ3 cm, SiO2, PE/TBME 7:3).
Compound 19 (4.6 g, 7.3 mmol, 95%) was isolated as an orange
75.8 (C-3) 118.6 (q, JC,F = 320.9 Hz, CF3), 123.4 (C-1), 128.8 (C-
5) 136.4 (C-2), 231.6 (C-10) ppm. IR: ν = 3368 (w), 2936 (w), 1978
˜
(s, CO), 1898 (s, CO), 1531 (w), 1524 (m), 1480 (m), 1237 (m), 1191
(m), 1138 (w), 1078 (w), 1005 (m), 918 (w), 861 (w), 819 (w), 734
(m), 700 (m) cm–1 (s). MS (70 eV): m/z (%) = 422 (12) [M]+, 394
(16) [M – CO]+, 366 (47) [M – 2 CO]+, 338 (62) [M – 3 CO]+, 286
(44) [M – Cr(CO)3]+, 286 (23) [M – Cr(CO)3 – SO2CF3]+. HRMS:
calcd.
for
C12H9CrF3O8S
421.9375;
found
421.9374.
C12H9CrF3O8S (422.25): calcd. C 34.13, H 2.15; found C 34.18, H
2.12.
Tricarbonyl{η6-[3,6-dimethoxy-2-(trifluoromethylsufonyl)phenyl
acetate]}chromium(0) (15): LDA in THF [prepared from nBuLi
(2.5 m, 1.0 mL, 2.4 mmol) in hexane and diisopropylamine (0.8 mL,
5.0 mmol) in THF (20 mL)] was added dropwise at –78 °C over
40 min to tricarbonyl[η6-(2,5-dimethoxyphenyl triflate)]chro-
mium(0) (13, 1.0 g, 2.4 mmol) in THF (20 mL). The color changed
from orange to deep red. After the mixture had warmed to 0 °C,
acetyl chloride (5 mL) was added. After addition of water (50 mL),
the mixture was extracted with CH2Cl2 (3ϫ50 mL). The collected
organic layers were washed with water (3ϫ20 mL) and dried with
anhydrous MgSO4. After solvent removal at reduced pressure, the
crude product was purified by column chromatography (30ϫ3 cm,
SiO2, PE/TBME 7:3). Compound 15 (5.8 g, 13.8 mmol, 99%) was
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solid (m.p. 115 °C, dec.). H NMR (400.1 MHz, CDCl3): δ = 3.64
(s, 3 H, OCH3), 4.20–4.21 [m, 2 H, 3(5)-H], 4.90–4.92 [m, 2 H,
2(6)-H], 7.20–7.51 [m, 15 H, P(C6H5)3] ppm. 13 C NMR
(400.1 MHz, CDCl3): δ = 55.9 (OCH3), 71.7 [C-3(5)], 83.8 [C-2(6)],
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118.6 (q, JC,F = 320.9 Hz, CF3), 122.5 (C-1), 128.6 [PCCH], 129.5
(PCCHCHCH) 133.5 (PCCHCH), 138.4 (PC), 138.7 (C-4), 238.5
(CO) ppm. 31P NMR (162 MHz, CDCl ): δ = 87.73 ppm. IR: ν =
˜
3
3059 (w), 1892 (s, CO), 1832 (s, CO), 1504 (m), 1463 (m), 1421 (m),
1244 (m), 1209 (s), 1135 (s), 1088 (m), 1018 (m), 872 (m) cm–1. MS
(70 eV): m/z (%) = 626 (10) [M]+, 598 (6) [M – CO]+, 570 (20) [M –
2 CO]+, 314 (90) [CrPPh3]+, 263 (100) [PPh3]+. HRMS: calcd. for
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isolated as a red oil. H NMR (400.1 MHz, CDCl3): δ = 2.32 [s, 3
C
28H22CrF3O6PS 626.0232; found 626.0233. C28H22CrF3O6PS
H, C(O)CH3], 3.69 (s, 3 H, 6-OCH3), 3.78 (s, 3 H, 3-OCH3), 4.77
(d, J = 7.1 Hz, 1 H, 5-H), 5.79 (d, J = 7.2 Hz, 1 H, 4-H) ppm. 13C
NMR (400.1 MHz, CDCl3): δ = 20.6 [C(O)CH3], 57.4 (6-OCH3),
(626.50): calcd. C 53.68, H 3.54; found C 52.83, H 3.43.
Dicarbonyl[η6-2-(trifluoromethylsulfonyl)phenol](triphenylphosphane)-
chromium(0) (20): LDA in THF [prepared from nBuLi (2.5 m,
1.36 mL, 3.4 mmol) in hexane and diisopropylamine (1.5 mL,
10.2 mmol) in THF (20 mL)] was added dropwise at –78 °C over
40 min to dicarbonyl(η6-phenyl triflate)(triphenylphosphane)chro-
mium(0) (18, 2.0 g, 3.4 mmol) in THF (20 mL). The color changed
from orange to deep red. After the mixture had warmed to 0 °C
and been treated with oxygen-free aq. HCl (10 %, to pH = 6),
CH2Cl2 (50 mL) was added, and the mixture was intensely stirred
for 5 min. After phase separation, the organic layer was collected
with a syringe and filtered into a Schlenk flask through a P4 frit
covered with a 5 cm thick layer of MgSO4, which was washed with
CH2Cl2. The solvent was removed at reduced pressure, and the
crude product was purified by column chromatography (30ϫ3 cm,
SiO2, PE/TBME 7:3). Compound 20 (1.9 g, 3.2 mmol, 95%) was
58.6 (3-OCH3), 65.7 (C-5), 77.9 (C-4), 81.2 (C-2), 120.2 (q, 1JC,F
=
328.0 Hz, CF3), 125.1 (C-6), 139.9 (C-3), 168.6 (C-1), 228.9 (CO)
ppm. IR: ν = 3129 (w), 2355 (w), 1985 (s, CO), 1938 (s, CO), 1902
˜
(s, CO), 1785 (m, C=O), 1492 (m), 1426 (m), 1366 (m), 1267 (m),
1207 (s), 1159 (s), 1110 (m), 1060 (m), 1033 (m), 879 (m), 844 (w).
MS (70 eV): m/z (%) = 464 (15) [M]+, 436 (17) [M – CO]+, 408 (25)
[M – 2 CO]+, 380 (34) [M – 3 CO]+, 337 (100) [M – 2 CO –
COCH3]+. HRMS: calcd. for C14H11CrF3O9S 463.9481; found
463.9480. C14H11CrF3O9S (464.29): calcd. C 36.22, H 2.39; found
C 36.23, H 2.42.
Dicarbonyl(η6-phenyl triflate)(triphenylphosphane)chromium(0)
(18): Triphenylphosphane (6.5 g, 24.9 mmol) was added to a solu-
tion of tricarbonyl(η6-phenyl triflate)chromium(0)[36] (16, 3.0 g,
8.3 mmol) in toluene. The reaction mixture was irradiated (125 W
mercury lamp, quartz filter) for 25 min in a photochemical immer-
sion cell fitted with a reflux condenser, which was cooled with
water. The reaction mixture was continuously flushed with argon.
The reaction progress was monitored by TLC. After the complete
consumption of the starting material (ca. 25 min), the reaction mix-
ture was irradiated for a further 20 min. The solvent was removed
at reduced pressure, and the crude product was purified by column
chromatography (30ϫ3 cm, SiO2, PE/TBME 7:3). Compound 18
(4.6 g, 7.6 mmol, 92 %) was isolated as an orange solid (m.p.
1
isolated as a red solid (m.p. 150 °C, dec.). H NMR (400.1 MHz,
CDCl3): δ = 4.30 (d, J = 7.3 Hz, 1 H, 6-H), 4.51 (t, J = 6.4 Hz, 1
H, 4 H), 5.53–5.58 (m, 2 H, 3-H, 5-H), 7.10 (br., 1 H, OH), 7.20–
7.51 [m, 15 H, P(C6H5)3] ppm. 13C NMR (400.1 MHz, CDCl3): δ
= 78.1 (C-6), 79.5 (C-4), 81.3 (C-2), 95.6 (C-5), 99.4 (C-3), 122.0
1
(q, JC,F = 325.3 Hz, CF3), 127.6 (PCCH), 128.4 (PCCHCHCH)
132.6 (PC), 134.3 (PCCHCH), 157.1 (C-1), 238.5 (CO) ppm. 31P
NMR (162 MHz, CDCl ): δ = 85.63 ppm. IR: ν = 2891 (w), 1883
˜
3
(s, CO), 1823 (s, CO), 1658 (w), 1504 (s), 1411 (s), 1134 (m), 1008
(m), 997 (m) cm–1. MS (70 eV): m/z (%) = 540 (10) [M – 2 CO]+,
314 (32) [CrPPh3]+, 277 (7) [M – 2 CO – PPh3]+, 262 (100)
[PPh3]+, 226 (3) [M – 2 CO – PPh3 – Cr]+, 184 (80) [PPh2]+, 108
(43) [PPh]+, 94 (11) [M – 2 CO – PPh3 – Cr – SO2CF3]+, 77 (21)
[Ph]+, 52 (33) [Cr]+.
1
105 °C, dec.). H NMR (400.1 MHz, CDCl3): δ = 4.59 (s, 1 H, 4-
H), 5.01 [d, J = 3.1 Hz, 4 H, 2(6)-H, 3(5)-H], 7.45 [br. s, 15 H,
P(C6H5)3] ppm. 13C NMR (400.1 MHz, CDCl3): δ = 82.1 [C-3(5)],
1
89.1 (C-4), 90.1 [C-2(6)], 118.6 (q, JC,F = 320.9 Hz, CF3), 129.0
(CPCCH), 130.4 (C-PCHCHCH), 133.9 (PCHCH), 138.4 (PC),
139.5 (C-1), 238.5 (CO) ppm. 31P NMR (162 MHz, CDCl3): δ =
Dicarbonyl[η6-4-methoxy-2-(trifluoromethylsulfonyl)phenol](triphen-
ylphosphane)chromium(0) (21): LDA in THF [prepared from nBuLi
87.73 ppm. IR: ν = 2362 (w), 1920 (s, CO), 1891 (s, CO), 1848 (s,
˜
Eur. J. Org. Chem. 0000, 0–0
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