L. Caron et al. / Tetrahedron Letters 42 (2001) 8837–8840
8839
reaction mixture was then heated under reflux for 1 h.
2.2. Phenyl-(3-sodium sulfonatophenyl)-(4-tert-
butylphenyl)-phosphine (B)
After cooling, chlorodiphenylphosphine (16.6 g, 75
mmol, 0.8 equiv.) or dichlorophenylphosphin (6.73 g,
38 mmol, 0.4 equiv.) in THF (10 mL) was added
dropwise and then heated under reflux for 1 h. Once the
reaction was complete, the mixture was poured into a
mixture of ice (ca. 50 g) and HCl (100 mL, 1N) and
stirred until magnesium dissolution. The aqueous phase
was extracted with toluene (3×35 mL) and the com-
bined organic layers were dried over anhydrous
MgSO4, filtered and concentrated by rotary evapora-
tion. The resulting oil was recrystallized from methanol
to give white crystals. Yield: ꢀ90%.
P(Ph)2(p-tBuPh) (5 g, 15.7 mmol) was dissolved in
concentrated sulfuric acid (18N, 96%, 27 mL). After
cooling to 5°C, the oleum (65%, 15 mL) was added slowly
under vigorous stirring and keeping the temperature
under 10°C. The reaction mixture was then kept at room
temperature for 2 h. The neutralization was carried out
under nitrogen atmosphere at 0°C by the slow, dropwise
addition of NaOH (380 mL, 5.5N). The water was
removed under vacuum. The remaining solid was
refluxed in methanol (150 mL) for 30 min and the
solution filtered hot to remove the sodium sulfate. The
solution was then evaporated to give a white solid which
was recrystallized from methanol to give white crystals.
Yield: 3.96 g (60%); 1H NMR: (D2O) 0.9 (9H, s, H1), 6.82
2. General procedure for the synthesis of
amphiphilic triphenylphosphine analogues
3
(11H, um, H4,5,11,12,14,15,16), 7.51 (1H, d, JHH=7 Hz,
3
H10), 7.60 (1H, d, JPH=8.1 Hz, H8); 13C{1H} NMR:
2.1. Bis-(3-sodium sulfonatophenyl)-(4-tert-butylphenyl)-
phosphine (A)
(D2O) 31.2 (C1, s), 34.5 (C2, s), 125.8 (C4, d, 3JPC=7 Hz),
3
126.5 (C10, s), 129.0 (C15, d, JPC=7 Hz), 129.5 (C11,16
,
2
1
br s), 130.7 (C8, d, JPC=27 Hz), 133.1 (C6, d, JPC=10
Hz), 133.9 (C14,5, t, 2JPC=19 Hz), 135.4 (C12, d, 2JPC=11
Hz), 136.2 (C13, d, 1J PC=10 Hz), 138.4 (C7, d, 1JPC=13
P(Ph)2(p-tBuPh) (5 g, 15.7 mmol) was dissolved in
concentrated sulfuric acid (18N, 96%, 8.5 mL). After
cooling to 5°C, the oleum (65%, 10.6 mL) was added
slowly under vigorous stirring and keeping the tempera-
ture under 10°C. The reaction mixture was then kept at
room temperature for 40 h. Excess of oleum was neutral-
ized by addition of 50 ml of degassed water. The mixture
was poured into mixture of ice (250 g) and water (250
mL) and dipentyl amine (4.94 g, 31 mmol, 1 equiv. per
sulfonate group) was then added. The ammonium salt of
the sulfonated phosphine was recovered from the acidic
aqueous layer by addition of ethyl acetate (3×60 mL).
The organic phase was washed with water (20×100 mL),
dried over anhydrous MgSO4, filtered and concentrated
by rotary evaporation. The resulting oil was dissolved
into isoamylic alcohol and extracted eight times with a
mixture of water (10 mL) and NaOH (2 mL, 2N). The
first and second fraction containing mainly sulfate ions
and phosphine oxide was kept away. The others were
concentrated in vacuo and a white solid was obtained.
This solid was recystallised from methanol to give white
crystals. Yield: 5.32 g (65%); 1H NMR: (D2O) 1.14 (9H,
3
Hz), 143.8 (C9, d, JPC=7 Hz), 151.7 (C3, s); 31P{1H}
NMR: (D2O, external H3PO4) −7.1 (s) IRFT (KBr) w
(cm−1): 2962 (vs), 2867 (m), 1457 (m), 1434 (m), 1389 (m),
1362 (m), 1340 (m), 1310 (m), 1215 (s), 1082 (s), 841 (m),
827 (m), 788 (w), 746 (m), 675 (m), 582 (m), 560 (m), 501
(m). Anal. calcd for C22H22NaO3PS·2H2O (M=456 g
mol−1): C, 57.33; H, 5.7. Found: C, 57.54; H, 5.29.
2.3. Bis-(4-tert-butylphenyl)-(3-sodium sulfonato-
phenyl)phosphine (C)
PPh(p-tBuPh)2 (5 g, 13.37 mmol) was dissolved in
concentrated sulfuric acid (18N, 96%, 12 mL). After
cooling to 5°C, the oleum (65%, 8 mL) was added slowly
under vigorous stirring and keeping the temperature
under 10°C. The reaction mixture was then kept at room
temperature for 18 h. Excess of oleum was neutralized
by addition of 50 ml of degassed water. The mixture was
poured into mixture of ice (100 g) and water (100 mL)
and dipentyl amine (2.1 g, 13.37 mmol, 1 equiv. per
sulfonate group) was then added. The ammonium salt of
the sulfonated phosphine was recovered from the acidic
aqueous layer by addition of ethyl acetate (3×75 mL).
The combined organic phases were washed with water
(20×100 mL), dried over anhydrous MgSO4, filtered and
concentrated by rotary evaporation. Dissolution of the
resulting oil in isoamylic alcohol (70 mL) followed by the
dropwise addition of NaOH (90 mL, 0.15N) caused the
precipitation of a white solid. This solid was filtered,
triturated and washed with warm heptane to give a white
3
s, H1), 7.34 (2H, t, JPH ꢀ3JHH=8.3 Hz, H5), 7.50 (2H,
t, 3JPH ꢀ3JHH=7 Hz, H12), 7.55 (4H, m, H4,11), 7.77 (2H,
3
3
d, JPH=7.8 Hz, H8), 7.82 (2H, d, JHH=7.8 Hz, H10);
13C{1H} NMR: (D2O) 30.9 (C1, s), 34.6 (C2, s), 126.3
(C11, d, 3JPC=7 Hz), 126.7 (C10, s), 129.9 (C4, d, 3JPC=6
2
1
Hz), 130.6 (C8, d, JPC=25 Hz), 132.0 (C6, d, JPC=9
Hz), 133.8 (C12, d, JPC=20 Hz), 136.5 (C5, d, JPC=16
2
2
1
3
Hz), 137.6 (C7, d, JPC=10 Hz), 143.3 (C9, d, JPC=8
Hz), 154.0 (C3, s); P{1H} NMR: (D2O, external H3PO4)
−7.7 (s) FTIR (KBr) w (cm−1): 2964 (m), 2869 (w), 1461
(w), 1447 (w), 1390 (m), 1366 (w), 1306 (w), 1201 (s), 1080
(w), 848 (w), 831 (m), 826 (w), 785 (m), 680 (m), 518 (m).
Anal. calcd for C22H21Na2O6PS2·4H2O (M=594 g
mol−1): C, 44.44; H, 4.88. Found: C, 44.51; H, 4.67.
1
solid. Yield: 3.18 g (50%); H NMR: (DMSO) 1.27 (18
H, s, H1), 7.15 (1H, t, 3JHHꢀ3JHP =7 Hz, H12), 7.21 (4H,