2-(3-Triphenylphosphoniophenyl)-4,5-diphenylimidazole brom-
ide. Pale yellow solid, characterised as the related perchlorate,
mp 159–161 ЊC (Found: C, 71.39; H, 4.49; N, 4.40; C39H30-
N2PؒClO4 requires C, 71.29; H, 4.60; N, 4.26%). Bromide salt:
δP(CDCl3) 23.10; m/z 555.9 base peak (Mϩ Ϫ 1, betaine), 556.9
(Mϩ).
2-(4-Triphenylphosphoniophenyl)-4,5-diphenylimidazole brom-
ide. Pale yellow solid, characterised as the related perchlorate,
mp 170–172 ЊC (Found: C, 71.30; H, 4.60; N, 4.26; C39H30N2Pؒ
ClO4 requires C, 71.29; H, 4.60; N, 4.26%). Bromide salt:
δP(CDCl3) 22.59; m/z 557.0 base peak (Mϩ).
2-(3-Tributylphosphoniophenyl)-1H-benzimidazolide. White
solid, mp 140–143 ЊC (decomp., from dichloromethane)
(Found: C, 70.23; H, 8.94; N, 6.82; C25H35N2Pؒ2H2O requires C,
69.74; H, 9.13; N, 6.51%); δP(CDCl3) 30.84; m/z (FAB) 395 base
peak (Mϩ ϩ 1).
2-(4-Tributylphosphoniophenyl)-1H-benzimidazolide. Cream
solid, mp 278–280 ЊC (from dichloromethane–diethyl ether)
(Found: C, 69.97; H, 8.89; N, 6.50; C25H35N2Pؒ2H2O requires
C, 69.74; H, 9.13; N, 6.51%); δP(CDCl3) 28.96; m/z base peak
394.1 (Mϩ).
2-(2-Triphenylphosphoniophenyl)-1H-phenanthro[9,10-d]imid-
azole bromide. Yellow crystals, mp >360 ЊC from dichloro-
methane–diethyl ether (Found: C, 73.90; H, 4.50; N, 4.43;
C39H28N2PؒBr requires C, 73.71; H, 4.44; N, 4.41%); δP(CDCl3)
26.76; m/z (FAB) 554.7 (Mϩ).
Derivatives of betaines and 4-nitrobenzyl bromide
Refluxing the betaines with an equimolar proportion of 4-
nitrobenzyl bromide in either acetonitrile or dimethylform-
amide resulted in the preparation of the following derivatives
which have been characterised.
2-(3-Triphenylphosphoniophenyl)-1H-phenanthro[9,10-d]-
imidazole bromide. Yellow solid, characterised as the related
perchlorate, mp 232–234 ЊC (Found: C, 71.41; H, 4.31; N, 4.22;
C39H28N2PؒClO4 requires C, 71.51; H, 4.31; N, 4.28%). Bromide
salt: δP(CDCl3) 22.99; m/z (FAB) 554 (Mϩ Ϫ 1, betaine), 555
(Mϩ).
2-(4-Triphenylphosphoniophenyl)-1H-phenanthro[9,10-d]-
imidazole bromide. Yellow solid, mp 240 ЊC (decomp.) (Found:
C, 73.76; H, 4.50; N, 4.42; C39H28N2PؒBr requires C, 73.71; H,
4.44; N, 4.41%); δP(CDCl3) 22.53; m/z 555.0 (Mϩ).
1-(4-Nitrobenzyl)-2-(4-triphenylphosphoniophenyl)-4,5-di-
phenylimidazole bromide. Yellow solid, characterised as the
related perchlorate, mp 164–165 ЊC (from DMF–diethyl ether)
(Found: C, 69.84; H, 4.37; N, 5.15; C46H35N3PؒClO6 requires C,
69.74; H, 4.38; N, 5.20%).
1-(4-Nitrobenzyl)-2-(2-triphenylphosphoniophenyl)-1H-phen-
anthro[9,10-d]imidazole bromide. Yellow solid, characterised as
the related perchlorate, mp 161–163 ЊC (from DMF–diethyl
ether) (Found: C, 69.92; H, 4.22; N, 5.31; C46H33N3PؒClO6
requires C, 69.92; H, 4.21; N, 5.32%).
2-(1H-Benzimidazol-2-yl)phenyltributylphosphonium brom-
ide. Off-white solid, characterised as the related perchlorate, mp
124–126 ЊC (Found: C, 60.62; H, 7.34; N, 5.62; C25H36N2PؒClO4
requires C, 60.66; H, 7.33; N, 5.66%); δP(Ϫ70 ЊC; CDCl3) 32.23;
m/z (FAB) 395.2 base peak (Mϩ).
1-(4-Nitrobenzyl)-2-(3-triphenylphosphoniophenyl)-1H-phen-
anthro[9,10-d]imidazole bromide. Yellow solid, characterised as
the related perchlorate, mp 184–186 ЊC (from DMF–diethyl
ether) (Found: C, 69.84; H, 4.25; N, 5.29; C46H33N3PؒClO6
requires C, 69.92; H, 4.21; N, 5.32%).
3-(1H-Benzimidazol-2-yl)phenyltributylphosphonium brom-
ide. White crystals, mp 180–182 ЊC (Found: C, 63.05; H, 7.67;
N, 5.79; C25H36N2PBr requires C, 63.16; H, 7.63; N, 5.89%);
δP(Ϫ70 ЊC; CDCl3) 31.82; m/z (FAB) 395.2 base peak (Mϩ).
4-(1H-Benzimidazol-2-yl)phenyltributylphosphonium brom-
ide. Off-white solid, mp 179–181 ЊC (Found: C, 62.89; H, 7.67;
N, 5.79; C25H36N2PBr requires C, 63.16; H, 7.63; N, 5.89%);
δP(Ϫ70 ЊC; CDCl3) 30.51; m/z (FAB) 395.0 (Mϩ).
1-(4-Nitrobenzyl)-2-(4-triphenylphosphoniophenyl)-1H-phen-
anthro[9,10-d]imidazole bromide. Yellow solid, characterised as
the related perchlorate, mp 188–190 ЊC (Found: C, 70.01; H,
4.21; N, 5.26; C46H33N3PؒClO6 requires C, 69.92; H, 4.21; N,
5.32%).
References
1 J. Abe and Y. Shirai, J. Am. Chem. Soc., 1996, 118, 4705.
2 E. Alcalde, Adv. Heterocycl. Chem., 1994, 60, 197, and refs. cited
therein.
Phosphonium betaines
Treatment of the phosphonium salts with an equimolar propor-
tion of aqueous sodium hydroxide in ethanol (or methanol
depending on the solubility of the salt) led to the formation of
the new stable phosphonium betaines which were isolated and
characterised.
2-(2-Triphenylphosphoniophenyl)-4,5-diphenylimidazolide.
Orange solid, mp >300 ЊC (decomp., from ethanol–water)
(Found: C, 81.52; H, 5.40; N, 4.87; C39H29N2PؒH2O requires C,
81.51; H, 5.44; N, 4.87%); δP(CDCl3) 15.60; m/z (FAB) 556.9
(Mϩ ϩ 1).
2-(4-Triphenylphosphoniophenyl)-4,5-diphenylimidazolide.
Orange solid, mp 210 ЊC (decomp., from ethanol–water)
(Found: C, 81.43; H, 5.30; N, 4.78; C39H29N2PؒH2O requires C,
81.51; H, 5.44; N, 4.87%); δP(CDCl3) 22.08; m/z (FAB) 556.7
(Mϩ ϩ 1).
2-(2-Triphenylphosphoniophenyl)-1H-phenanthro[9,10-d]-
imidazolide. Orange solid, mp >300 ЊC (from ethanol–water)
(Found: C, 81.82; H, 5.10; N, 4.86; C39H27N2PؒH2O requires C,
81.80; H, 5.10; N, 4.89%); δP(CDCl3) 19.87; m/z (FAB) 554.9
base peak (Mϩ ϩ 1).
3 D. W. Allen and P. Benke, J. Chem. Soc., Perkin Trans. 1, 1995,
2789.
4 D. G. Gilheany, Chem. Rev., 1994, 94, 1339.
5 C. Lambert, S. Stadler, G. Bourhill and C. Bräuchle, Angew. Chem.,
Int. Ed. Engl., 1996, 35, 644.
6 E. Alcalde, I. Dinares, L. Perez and T. Roca, Synthesis, 1992, 395,
and refs. cited therein.
7 I. Isikdag, U. Ucucu and B. Cakir, J. Fac. Pharm. Gazi., 1989, 6,
49.
8 L. Horner, G. Mummenthey, H. Moser and P. Beck, Chem. Ber.,
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9 E. Alcalde, I. Denares, J. Frigola, J. Ruis and C. Miravitlles,
J. Chem. Soc., Chem. Commun., 1989, 1086; E. Alcalde, I. Denares,
J. Frigola, C. Jaime, J.-P. Fayet, M.-C. Vertut, C. Miravitlles and
J. Rius, J. Org. Chem., 1991, 56, 4223; E. Alcalde, I. Denares,
J. Elguero, J.-P. Fayet, M. C. Vertut, C. Miravitlles and E. Molins,
J. Org. Chem., 1987, 52, 5009.
10 C. J. Dik-Edixhoven, H. Schenk and H. Van der Meer, Crystallogr.
Struct. Commun., 1973, 2, 23; A. Escande and J. L. Galigne, Acta
Crystallogr., Sect. B, 1974, 30, 1647.
11 I. Dance and M. Scudder, J. Chem. Soc., Chem. Commun., 1995,
1039.
12 I. Dance and M. Scudder, Chem. Eur. J., 1996, 2, 481.
13 G. M. Sheldrick, SHELXL93, an integrated system for solving
and refining crystal structures from diffraction data, University of
Göttingen, Germany, 1993.
2-(4-Triphenylphosphoniophenyl)-1H-phenanthro[9,10-d]-
imidazolide. Orange solid, mp 261–263 ЊC (from ethanol–water)
(Found: C, 81.90; H, 5.09; N, 4.85; C39H27N2PؒH2O requires C,
81.80; H, 5.10; N, 4.89%); δP(CDCl3) 22.30; m/z (FAB) 555.0
(Mϩ ϩ 1).
14 D. W. Allen and X. Li, J. Chem. Soc., Perkin Trans. 2, 1997, 1099.
2-(2-Tributylphosphoniophenyl)-1H-benzimidazolide. White
solid, mp 133–135 ЊC (from dichloromethane–diethyl ether)
(Found: C, 74.87; H, 6.71; N, 7.0; C25H35N2P requires C, 76.11;
H, 8.94; N, 7.10%); m/z (FAB) 394.1 (Mϩ).
Paper 7/04358I
Received 20th June 1997
Accepted 10th September 1997
340
J. Chem. Soc., Perkin Trans. 1, 1998