2126
B. Breit, E. Fuchs
PAPER
1H NMR (400.130 MHz, CDCl3): d = 3.74 (s, 3 H, OCH3), 6.48–
6.51 (dd, J = 7.7 Hz, J = 5.2 Hz, 1 H, H6), 6.90–6.93 (m, 2 H), 7.07
(t, J = 7.5 Hz, 1 H), 7.17–7.30 (m, 4 H), 7.35–7.39 (m, 2 H, H3¢¢),
Bidentate Ligands 5 and 6; General Procedure
To a soln of (S)-(1,1¢-binaphthyl-2,2¢-dioxy)chlorophosphine (4,
1.3–1.5 equiv) in toluene was added slowly a soln of enantiomeri-
cally pure phosphabarrelene (+)- or (–)-1d or (+)- or (–)-1e in tolu-
ene at –40 °C. Subsequently Et3N (1.3–1.5 equiv) was added and
the soln was warmed to r.t. over 5 h and stirred overnight. The or-
ganic phase was washed with H2O (3 × 15 mL), the aqueous phases
were reextracted with toluene (3 × 10 mL), and the combined or-
ganic phases were dried (MgSO4). After evaporation of the solvent
in vacuo, the residue was dissolved in CH2Cl2 (10 mL) and filtered
through a small pad of neutral alumina (2 × 3 cm, activity grade IV).
The alumina was flushed with additional CH2Cl2 (60 mL) and the
combined filtrates were evaporated to dryness in vacuo to give the
bidentate phosphabarrelenes in analytically pure form.
3
7.49 (t, JH,H = 7.3 Hz, 1 H, H4¢), 7.57–7.61 (m, 2 H, H3¢), 7.69–
7.74 (m, 2 H, H2¢¢), 7.81–7.84 (m, 2 H, H2¢), 7.83 (d, 3JH,P = 32.7
Hz, 1 H, H12a), 8.00 (d, 3JH,P = 31.8 Hz, 1 H, H9a), 8.03–8.07 (m, 1
H, H3) (a interchangeable assignments).
31P NMR (121.468 MHz, CDCl3): d = 11.1 (s).
Deprotection: Oxide rac-ox-1c (560 mg, 1.25 mmol, 1.0 equiv) was
dissolved in DCE (15 mL) in a pressure vessel at r.t. A suspension
of BBr3·SMe2 (1.375 g, 4.40 mmol, 3.5 equiv) in DCE (6 mL) was
added to the mixture which was then heated to 80 °C overnight. The
reaction was cooled to 0 °C and hydrolyzed by cautious addition of
ice. The organic phase was washed with H2O (3 × 10 mL) and the
aqueous phases were reextracted with CH2Cl2 (2 × 10 mL). The
combined organic phases were dried (MgSO4) and evaporated to
dryness in vacuo. The residue was purified by flash chromatogra-
phy (silica gel, cyclohexane–EtOAc, 3:1) to give 11-(2-hy-
droxyphenyl)-8,10-diphenyl-1-phosphatricyclo[6.2.2.02,7]dodeca-
2(7),3,5,9,11-pentaene 1-oxide (rac-ox-1e) in analytically pure
form; yield: 508 mg (94%).
3-{8,11-Diphenyl-1-phosphatricyclo[6.2.2.02,7]dodeca-
2(7),3,5,9,11-pentaen-10-yl}phenyl(S)-1,1¢-Binaphthyl-2,2¢-diyl
Phosphite [(+)-5a] from (+)-1d
Starting from 4 (88.7 mg, 0.253 mmol) in toluene (4.0 mL) and (+)-
1d (81.0 mg, 0.195 mmol) in toluene (8.0 mL) and using Et3N (27.0
mg, 0.264 mmol), 5a was obtained as a colorless solid; yield: 124
mg (87%); mp 132–138 °C.
1H NMR (300.066 MHz, CDCl3): d = 6.51–6.56 (dd, J = 7.5 Hz,
J = 5.3 Hz, 1 H, H6), 6.82–6.87 (m, 1 H), 7.00 (d, J = 7.5 Hz, 1 H),
7.08–7.38 (m, 7 H), 7.50–7.55 (m, 1 H, H4¢), 7.60–7.65 (m, 2 H,
[a]D20 +77.9 (c 1.09, CHCl3).
1H NMR (499.870 MHz, CDCl3): d = 6.60 (d, 3JH,H = 6.9 Hz, 1 H,
H6), 7.01–7.07 (m, 2 H, H4, H5), 7.13–7.15 (m, 1 H, H4¢¢¢), 7.26–
7.35 (m, 7 H), 7.37–7.49 (m, 4 H), 7.51–7.57 (m, 3 H, H4¢, H2¢¢¢,
H6¢¢¢), 7.60 (d, J = 8.8 Hz, 1 H), 7.64 (pt, 3JH,H = 7.6 Hz, 2 H, H3¢),
7.74 (d, 3JH,H = 7.7 Hz, 2 H, H2¢¢), 7.83 (d, 3JH,H = 7.5 Hz, 2 H, H2¢),
7.86–7.88 (m, 1 H, H3), 7.90–7.93 (m, 2 H), 7.95 (d, J = 8.2 Hz, 1
H), 8.01 (d, J = 8.8 Hz, 1 H), 8.11 (d, 3JH,P = 5.8 Hz, 1 H, H9a), 8.12
(d, 3JH,P = 5.7 Hz, 1 H, H12a) (a interchangeable assignments).
3
H3¢), 7.70–7.73 (m, 4 H, H2¢¢, H2¢), 7.96 (d, JH,P = 29.7 Hz, 1 H,
H9a), 8.03–8.08 (m, 1 H, H3), 8.07 (d, 3JH,P = 32.4 Hz, 1 H, H12a),
9.62 (s, 1 H, OH) (a interchangeable assignments).
31P NMR (121.468 MHz, CDCl3): d = 18.3 (s).
Reduction: To a soln of rac-ox-1e (128 mg, 0.296 mmol, 1.0 equiv)
in toluene (8 mL) in a pressure vessel was added trichlorosilane
(140 mL, 188 mg, 1.385 mmol, 4.7 equiv) at 0 °C. The mixture was
stirred for 10 min at r.t. and then it was heated to 110 °C overnight.
The mixture was cooled to r.t., cautiously poured into aq 2 M NaOH
(15 mL), and the H2O phase was extracted with toluene (2 × 10
mL). The combined organic phases were washed with H2O (3 × 8
mL), dried (MgSO4) and evaporated to dryness in vacuo. The resi-
due was purified by flash chromatography (silica gel, cyclohexane–
EtOAc, 5:1) to give rac-1e in analytically pure form as a colorless
solid; yield: 106 mg (86%); mp 205–210 °C.
13C NMR (125.692 MHz, CDCl3): d = 63.8 (d, 3JC,P = 2.1 Hz, C8),
117.9 (dd, 3JC,P = 13.3 Hz, 3JC,P = 7.0 Hz, C2¢¢¢), 119.3 (d, 3JC,P = 8.8
3
Hz, C4¢¢¢), 121.68, 121.71, 122.0 (d, JC,P = 13.6 Hz, C6¢¢¢), 122.9
(d, J = 2.4 Hz, 2 C, quart. C), 124.1 (d, 3JC,P = 13.3 Hz, C4), 124.3
3
(C6), 125.0, 125.2, 125.9 (d, JC,P = 13.0 Hz, 2 C, C2¢¢), 126.2,
126.4, 126.9, 127.0, 127.2 (d, 4JC,P = 1.5 Hz, C5), 127.6 (C4¢), 127.7
(d, 5JC,P = 1.2 Hz, C4¢¢), 128.3, 128.4, 128.6 (d, 4JC,P = 0.9 Hz, 2 C,
C3¢¢), 128.9 (2 C, C2¢), 129.1 (2 C, C3¢), 129.8, 129.9, 130.5, 131.3
(quart. C), 131.6 (quart. C), 131.8 (d, 2JC,P = 39.1 Hz, C3), 132.6 (d,
J = 1.2 Hz, quart. C), 132.8 (d, J = 1.2 Hz, quart. C), 138.5 (d,
Resolution via preparative HPLC (Chiralpak AD-H, n-heptane–
EtOH, 50:50):
(–)-1e: [a]D20 –13.9 (c 0.77, CHCl3).
(+)-1e: [a]D20 +13.4 (c 0.76, CHCl3).
1H NMR (300.064 MHz, CDCl3): d = 5.11 (s, 1 H, OH), 6.55–6.58
(m, 1 H, H6), 6.83 (d, 3JH,H = 8.1 Hz, 1 H, H3¢¢¢), 6.88–6.93 (m, 1 H,
H5¢¢¢), 7.00–7.03 (m, 2 H, H4, H5), 7.10–7.16 (m, 1 H, H4¢¢¢), 7.23–
7.35 (m, 4 H, H3¢¢, H4¢¢, H6¢¢¢), 7.46–7.51 (m, 1 H, H4¢), 7.57–7.62
(m, 2 H, H3¢), 7.67–7.70 (m, 2 H, H2¢¢), 7.75–7.78 (m, 2 H, H2¢),
7.78–7.84 (m, 1 H, H3), 8.06 (d, 3JH,P = 6.2 Hz, 1 H, H9a), 8.07 (d,
3JH,P = 6.0 Hz, 1 H, H12a) (a interchangeable assignments).
2JC,P = 24.8 Hz, C1¢¢), 140.6 (d, JC,P = 25.1 Hz, C1¢¢¢), 140.8 (d,
2
1JC,P = 11.2 Hz, C2), 141.0 (C1¢), 146.9 (d, J = 2.4 Hz, quart. C),
147.2 (d, 2JC,P = 4.5 Hz, C9a), 147.5 (d, J = 4.5 Hz, quart. C), 148.4
(d, 2JC,P = 4.8 Hz, C12a), 151.8 (d, 1JC,P = 16.1 Hz, C10b), 151.9 (dd,
4
1
2JC,P = 7.9 Hz, JC,P = 1.2 Hz, C3¢¢¢), 152.4 (d, JC,P = 16.0 Hz,
C11b), 155.0 (d, 2JC,P = 3.3 Hz, C7) (a and b interchangeable assign-
ments).
31P NMR (121.474 MHz, CDCl3): d = 144.8 (s, P13), –68.9 (s, P1).
HRMS: m/z calcd for C49H32O3P2: 730.1827; found: 730.1812.
3-{8,11-Diphenyl-1-phosphatricyclo[6.2.2.02,7]dodeca-
2(7),3,5,9,11-pentaen-10-yl}phenyl(S)-1,1¢-Binaphthyl-2,2¢-diyl
Phosphite [(+)-5b] from (–)-1d
Starting from 4 (38.3 mg, 0.109 mmol) in toluene (3.0 mL) and (–)-
1d (35.0 mg, 0.084 mmol) in toluene (5.0 mL) using Et3N (11.6 mg
(0.114 mmol), 5b was obtained as a colorless solid; yield: 59 mg
(96%); mp 132–138 °C.
3
13C NMR (75.451 MHz, CDCl3): d = 63.8 (d, JC,P = 2.6 Hz, C8),
115.9 (C3¢¢¢), 120.9 (C5¢¢¢), 124.2 (d, 3JC,P = 13.2 Hz, C4), 124.4 (d,
3JC,P = 1.2 Hz, C6), 125.9 (d, 3JC,P = 12.7 Hz, 2 C, C2¢¢), 126.6 (d,
4
2JC,P = 23.0 Hz, C1¢¢¢), 127.3 (d, JC,P = 1.7 Hz, C5), 127.6 (C4¢),
4
127.7 (d, 5JC,P = 1.7 Hz, C4¢¢), 128.6 (d, JC,P = 1.2 Hz, 2 C, C3¢¢),
3
128.8 (2 C, C2¢), 128.9 (d, JC,P = 10.7 Hz, C6¢¢¢), 128.9 (C4¢¢¢),
2
129.1 (2 C, C3¢), 131.8 (d, JC,P = 38.6 Hz, C3), 138.5 (d,
[a]D20 +73.2 (c 1.05, CHCl3).
1
2JC,P = 24.5 Hz, C1¢¢), 140.9 (C1¢), 141.1 (d, JC,P = 12.4 Hz, C2),
1H NMR (499.870 MHz, CDCl3): d = 6.58 (d, 3JH,H = 6.9 Hz, 1 H,
H6), 7.00–7.06 (m, 2 H, H4, H5), 7.11–7.13 (m, 1 H, H4¢¢¢), 7.25–
7.37 (m, 7 H), 7.40–7.47 (m, 4 H), 7.50–7.53 (m, 3 H, H4¢, H2¢¢¢,
H6¢¢¢), 7.58 (d, J = 8.8 Hz, 1 H), 7.63 (pt, 3JH,H = 7.7 Hz, 2 H, H3¢),
7.70 (d, 3JH,H = 7.7 Hz, 2 H, H2¢¢), 7.81 (d, 3JH,H = 7.5 Hz, 2 H, H2¢),
7.83–7.84 (m, 1 H, H3), 7.87 (d, J = 8.6 Hz, 2 H), 7.94 (d, J = 8.3
147.1 (d, 2JC,P = 4.6 Hz, C9), 150.2 (d, 1JC,P = 18.4 Hz, C11), 150.6
2
3
(d, JC,P = 4.0 Hz, C12), 152.2 (d, JC,P = 2.6 Hz, C2¢¢¢), 152.8 (d,
1JC,P = 17.6 Hz, C10), 154.9 (d, 2JC,P = 3.3 Hz, C7).
31P NMR (121.468 MHz, CDCl3): d = –63.0 (s).
HRMS: m/z calcd for C29H21OP: 416.1330; found: 416.1320.
Synthesis 2006, No. 13, 2121–2128 © Thieme Stuttgart · New York