B. Breit et al.
in toluene (300 mL). The suspension was washed with water (5100 mL)
and the aqueous phases were extracted with more toluene (5100 mL).
The combined organic phases were dried (Na2SO4) and the solvent was
removed in vacuo. The residue was dissolved in petroleum ether
(600 mL, 5% triethylamine) and was filtered through a plug of silica
(7 cm in diameter and 7 cm in height) with additional petroleum ether
(600 mL, 5% triethylamine). The solvent was removed in vacuo and the
remaining red residue was dissolved in methanol (150 mL) and heated at
reflux for 2 h. A precipitate formed that was collected by filtration, was
washed with a little methanol, and was dried in vacuum to give phospha-
10,11-Bis-(2,4-dimethylphenyl)-4-methyl-8-phenyl-1-phosphatricyclo[6.2.
2.02,7]dodeca-2(7),3,5,9,11-pentaene (4d) and 10,11-bis-(2,4-dimethyl-
phenyl)-5-methyl-8-phenyl-1-phosphatricyclo[6.2.2.02,7]dodeca-2(7),3,5,9,
11-pentaene (4e): 3-Bromo-4-fluorotoluene (0.5 mL of a total amount of
2.20 mL, 3.30 g, 17.46 mmol) was added to a suspension of magnesium
turnings (0.508 g, 20.91 mmol) and bis-2,6-(2,4-dimethylphenyl)-4-phenyl-
barrelene 4b (5.48 g, 35%) as
a colorless solid. M.p. 110–1128C;
1H NMR (500.003 MHz, CDCl3): d=1.17 (d, 3JH,H =6.8 Hz, 12H; H-2’’),
2.73 (sept, 2H; H-1’’), 6.49–6.50 (m, 1H; H-6), 6.94–6.99 (m, 2H; H-4, H-
5), 7.40 (d, 3JH,P =7.3 Hz, 2H; H-9, H-12), 7.45–7.58 (m, 1H; H-4’), 7.56–
7.60 (m, 2H; H-3’), 7.69–7.71 (m, 1H; H-3), 7.73–7.74 ppm (m, 2H; H-
2’); 13C NMR (125.725 MHz, CDCl3): d=21.9 (d, 3JC,P =8.2 Hz, 2C; C-
3
2
2’’a), 22.1 (d, JC,P =8.8 Hz, 2C; C-2’’b), 34.3 (d, JC,P =27.3 Hz, 2C; C-1’’),
61.9 (C-8), 123.4 (d, 3JC,P =0.9 Hz, C-6), 123.4 (d, 3JC,P =12.7 Hz, C-4),
phosphabenzene (3c) in THF (35 mL). After the reaction started (exo-
thermicity) the remaining 3-bromo-4-fluorotoluene was added slowly, to
keep the mixture at smooth reflux. Subsequently, the mixture was heated
for a further 3 h under reflux. After cooling to RT, the mixture was
quenched with water (5 mL). The solvent was removed in vacuo and the
residue was extracted with diethyl ether (200 mL) and dichloromethane
(150 mL). The combined organic phases were washed with water (3
150 mL), and the aqueous phases were reextracted with diethyl ether (3
120 mL). The combined organic phases were dried (Na2SO4) and the sol-
vent was removed in vacuo. The residue was suspended in petroleum
ether (150 mL, 5% triethylamine) and was filtered through silica gel
(3 cm diameter, 5 cm height). The silica gel was washed with additional
petroleum ether (50 mL, 5% triethylamine) and the solvent was evapo-
rated in vacuo. The red residue was dissolved in methanol (250 mL) and
heated under reflux for 2 h. The precipitate formed was collected by fil-
tration, was washed with a little methanol, and was dried in vacuo to give
the phosphabarrelene isomer mixture 4d and 4e (0.120 g, 3%). Concen-
tration of the mother liquor and cooling to 48C afforded a further prod-
uct mixture 4d and 4e (0.770 g, 16%) as a colorless solid (total yield:
19%, ratio 4d/4e 54:46 determined by NMR spectroscopy). M.p. 125–
1268C; 1H NMR (400.136 MHz, CDCl3): d=2.18 (s, 3H; CH3), 2.20 (s,
4
126.4 (d, JC,P =1.5 Hz, C-5), 127.1 (C-4’), 128.7 (2C; C-3’), 128.9 (2C; C-
2
1
2’), 130.8 (d, JC,P =37.8 Hz, C-3), 142.0 (C-1’), 142.6 (d, JC,P =11.5 Hz, C-
2), 143.7 (d, 2JC,P =5.5 Hz, 2C; C-9, C-12), 156.9 (d, 2JC,P =4.2 Hz, C-7),
160.5 ppm (d, 1JC,P =17.3 Hz, 2C; C-10, C-11). Assignment of 1H and 13C
resonances was based on APT, DQF-COSY (short-range H,H COSY)
and edHSQC (short-range H,C COSY) experiments; 31P NMR
(121.469 MHz, CDCl3): d = À72.6 ppm (s); elemental analysis calcd (%)
for C23H25P (332.4): C 83.10, H 7.57; found: C 83.24, H 7.82.
10,11-Bis-(2,4-dimethylphenyl)-8-phenyl-1-phosphatricyclo[6.2.2.02,7]do-
A
a total amount of 6.20 mL, 9.93 g, 56.73 mmol) was added to a suspension
of magnesium turnings (1.37 g, 56.73 mmol)
and bis-2,6-(2,4-dimethylphenyl)-4-phenylphos-
phabenzene (3c) in THF (70 mL). After the
start of the reaction (exothermicity) the re-
maining ortho-fluorobromobenzene was added
slowly to keep the mixture under smooth
reflux. Subsequently, the mixture was heated
for a further 3 h under reflux. After cooling to
RT, the mixture was quenched with water
(5 mL) and the solvent was removed in vacuo.
6H; CH3), 2.21 (s, 6H; CH3), 2.31 (s, 12H; CH3), 2.32 (s, 3H; CH3), 6.38
The residue was extracted with diethyl ether (200 mL) and dichlorome-
thane (200 mL). The combined organic phases were washed with water
(3150 mL), and the aqueous phases were reextracted with diethyl ether
(3120 mL). The combined organic phases were dried (Na2SO4) and the
solvent was removed in vacuo. The residue was suspended in petroleum
ether (5% triethylamine) and was filtered through silica (plug diameter
7 cm, height 6 cm) followed by washing the silica gel with more petrole-
um ether (600 mL, 5% triethylamine). The solvent was removed in
vacuo and the oily residue was taken up in methanol (400 mL) and
heated under reflux for 2 h. The precipitate formed was collected by fil-
tration and was washed with a small portion of methanol to give phos-
phabarrelene 4c (5.64 g, 47%) as a colorless powder. M.p. 168–1698C;
1H NMR (499.870 MHz, CDCl3): d=2.23 (s, 6H; CH3), 2.33 (s, 6H;
3
(s, 1H; H-6, 4e), 6.44 (d, 3JH,H =7.7 Hz, 1H; H-6, 4d), 6.81 (d, JH,H
=
3
7.7 Hz, 1H; H-5, 4d), 6.87 (d, JH,H =6.8 Hz, 1H; H-4, 4e), 6.93–6.99 (m,
12H; H-3’’, H-5’’, H-6’’, 4d and 4e), 7.45–7.50 (m, 2H; H-4’, 4d and 4e),
7.55–7.60 (m, 4H; H-3’, 4d and 4e), 7.64 (d, J=9.0 Hz, 1H), 7.69 (d, J=
8.6 Hz, 1H), 7.71–7.75 ppm (m, 8H); 13C NMR (125.725 MHz, CDCl3):
d=20.6 (CH3), 21.0 (4C; C-4’’-CH3, 4d and 4e), 21.1 (d, 4JC,P =2.9 Hz,
2C; C2’’-CH3), 21.2 (d, 4JC,P =2.9 Hz, 2C; C2’’-CH3), 21.5 (CH3), 63.2 (d,
3JC,P =2.9 Hz, C-8), 63.5 (d, 3JC,P =2.9 Hz, C-8), 123.8 (C-6), 124.4 (d,
3JC,P =13.1 Hz, C-4, 4e), 125.3 (C-6), 126.4 (4C; C-5’’ or C-6’’), 127.2 (C-
5, 4d), 127.3 (C-4’), 127.4 (C-4’), 128.09 (d, JC,P =7.3 Hz, 2C; C-5’’ or C-
6’’), 128.13 (d, JC,P =5.8 Hz, 2C; C-5’’ or C-6’’), 128.90 (4C; C-2’ or C-3’),
2
128.94 (4C; C-2’ or C-3’), 131.0 (4C; C-3’’), 131.4, 132.3 (d, JC,P
=
3
CH3), 6.59 (d, JH,H =7.1 Hz, 1H; H-6), 6.96–7.02 (m, 6H; H-3’’, H-5’’, H-
36.3 Hz, C-3), 133.4 (d, JC,P =13.1 Hz), 135.2 (4C; C-2’’*), 136.8, 136.9
(4C; C-4’’*), 137.5 (d, 2JC,P =21.8 Hz, 2C; C-1’’), 137.6 (d, 2JC,P =23.6 Hz,
2C; C-1’’), 138.7 (d, JC,P =14.5 Hz), 141.4 (C-1’), 141.6 (C-1’), 142.2 (d,
1JC,P =14.5 Hz, C-2), 149.6 (d, 2JC,P =4.4 Hz, 2C; C-9, C-12), 149.9 (d,
2JC,P =2.9 Hz, 2C; C-9, C-12), 152.6 (d, 2JC,P =2.9 Hz, C-7), 154.6 (d,
6’’), 7.04–7.10 (m, 2H; H-4, H-5), 7.49 (t, 3JH,H =7.4 Hz, 1H; H-4’), 7.58–
2
7.61 (m, 2H; H-3’), 7.75 (d, 3JH,H =7.4 Hz, 2H; H-2’), 7.76 (d, JH,P
=
6.3 Hz, 2H; H-9, H-12), 7.82–7.86 ppm (m, 1H; H-3); 13C NMR
(125.692 MHz, CDCl3): d=21.0 (2C; C-4’’-CH3), 21.1 (d, 4JC,P =7.9 Hz,
3
2C; C-2’’-CH3), 63.5 (C-8), 123.9 (d, 3JC,P =12.4 Hz, C-4), 124.0 (d, JC,P
=
1
1JC,P =20.4 Hz, 2C; C-10, C-11), 155.0 (d, JC,P =21.8 Hz, 2C; C-10, C-11),
4
0.6 Hz, C-6), 126.4 (2C; C-5’’ or C-6’’), 126.8 (d, JC,P =1.5 Hz, C-5), 127.4
(C-4’), 128.1 (d, JC,P =6.1 Hz, 2C; C-5’’ or C-6’’), 128.9 (2C; C-2’), 129.0
(2C; C-3’), 131.0 (2C; C-3’’), 131.3 (d, 2JC,P =36.9 Hz, C-3), 135.2 (d,
155.6 ppm (d, 2JC,P =4.4 Hz, C-7). *Assignment interchangeable;
31P NMR (121.474 MHz, CDCl3): d = À56.5 (s), À57.8 ppm (s); elemen-
tal analysis calcd (%) for C34H31P (470.3): C 86.82, H 6.59; found: C
86.41, H 6.64.
J
C,P =1.8 Hz, 2C; C-2’’ or C-4’’), 136.9 (d, JC,P =1.5 Hz, 2C; C-2’’ or C-4’’),
137.4 (d, 2JC,P =22.1 Hz, 2C; C-1’’), 141.3 (C-1’), 142.1 (d, 1JC,P =15.1 Hz,
2
1
General procedure for the preparation of rhodium complexes 5a–c: The
corresponding phosphabarrelene 4a–c (221.2 mmol) was added to a solu-
tion of rhodium dicarbonyl chloride dimer (21.5 mg, 55.3 mmol) in di-
chloromethane (4 mL). Gas evolution was observed. After stirring for
30 min at room temperature the solvent was removed in vacuo to give
the corresponding rhodium complex 5a–c in quantitative yield.
C-2), 149.6 (d, JC,P =3.6 Hz, 2C; C-9, C-12), 154.7 (d, JC,P =21.2 Hz, 2C;
C-10, C-11), 155.3 ppm (d, 2JC,P =3.3 Hz, C-7). Assignment of 1H and 13C
resonances was based on APT, DQF-COSY (short-range H,H COSY),
and edHSQC (short-range H,C COSY) experiments; 31P NMR
(121.474 MHz, CDCl3): d=À57.1 ppm (s); HRMS (EI): m/z: calcd for
C33H29P: 456.2007; found: 456.2004.
6936
ꢀ 2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Chem. Eur. J. 2006, 12, 6930 – 6939