SYNTHESIS OF UNSYMMETRICAL PHOSPHORUS(III)–ARENE MACROCYCLE
613
In the second step, macrocycle 6 was assembled
from 4 and 2 or from 5 and 1 in a dilute toluene
solution at 90‒95°C. The IR spectrum of unstable and
readily oxidizable oily compound 6 lacked P‒N
stretching band typical of 4 and 5. The phosphorus
signal appeared in the 31P NMR spectrum of 6 as
a doublet at δP 165.80 ppm, which was located in
a weaker field relative to the signal of the initial com-
pound. Sulfurization of 6 with elemental sulfur en-
hanced the stability and provided an additional support
for the proposed structure. The macrocyclic structure
of 6 and 7 followed from the H and P, IR, and mass
spectral data. The IR spectrum of 7 displayed an ab-
sorption band at 689 cm–1 typical of P=S group, in
keeping with our previous data for analogous sym-
metrical macrocycles [7].
1H NMR spectrum, δ, ppm: 1.64 s (6H, CH3), 3.95 s
(2H, CH2), 6.77 d and 7.04 d (4H, C6H4CMe2), 6.91 d
and 6.99 d (4H, C6H4CH2), 7.57 m (3H, Ph), 7.94 m
(2H, Ph). 31P NMR spectrum: δP 165.80 ppm, d. Mass
spectrum: m/z 663.40 [M + Na]+.
2,2-Dimethyl-5,11-diphenyl-4,6,10,12-tetraoxa-
5λ5,11λ5-diphospha-1,3,7,9(1,4)-tetrabenzenacyclo-
dodecaphane-5,11-dithione (7). Elemental sulfur,
3 mmol (0.1 g), was added to a solution of 1.5 mmol
(1 g) of compound 6 in 20 mL of anhydrous toluene,
and the mixture was kept for 24 h at room temperature.
The solvent was removed under reduced pressure
(water-jet pump), and the residue was purified by silica
gel column chromatography using benzene as eluent.
The product was dried for 2 h at 20°C under reduced
pressure (10 mm). Yield 76%, crystalline solid,
mp 240–242°C. IR spectrum, ν, cm–1: 1438 (P‒C),
1
31
The yields of compound 6 according to pathways a
and b were equally high, which is important from the
preparative viewpoint.
1
1192 (O‒C), 689 (P=S). H NMR spectrum, δ, ppm:
1.66 s (6H, CH3), 3.99 s (2H, CH2), 6.78 d and 7.03 d
(4H, C6H4CMe2), 6.85 d and 7.11 d (4H, C6H4CH2),
7.62 m (3H, Ph), 8.22 m (2H, Ph). 31P NMR spectrum:
δP 83.63 ppm, d. Mass spectrum: m/z 705.11 [M + H]+.
Found, %: C 67.92; H 4.93; P 8.68; S 9.24.
C40H34O4P2S2. Calculated, %: C 68.17; H 4.86;
P 8.79; S 9.10.
Compounds 4 and 5 were synthesized according to
the procedures described in [2, 8, 9]. A mixture of
1.8 mmol bisphenol 1 or 2 and 3.6 mmol of 3 was
heated for 2 h at 115‒120°C until the amount of
evolved diethylamine attained nearly theoretical value,
and the mixture was kept for 1 h under reduced pres-
sure (1 mm) at that temperature; compounds 4 and 5
were obtained in 96‒97% yield as viscous materials.
4,4′-Methylenedi(benzene-4,1-diyl) bis(N,N-di-
ethyl-P-phenylphosphonamidite) (4) [4]. IR spec-
trum, ν, cm–1: 1436 (P‒C), 1186 (O‒C), 925 (P‒N).
31P NMR spectrum: δP 131.1 ppm. Mass spectrum:
m/z 559.63 [M + H]+. Found, %: C 70.90; H 7.10;
P 11.03. C33H40N2O2P2. Calculated, %: C 70.97;
H 7.17; P 11.11.
4,4′-(Propane-2,2-diyl)di(benzene-4,1-diyl) bis-
(N,N-diethyl-P-phenylphosphonamidite) (5) [2]. IR
spectrum, ν, cm–1: 1438 (P‒C), 1188 (O‒C), 930
(P‒N). 31P NMR spectrum: δP 131.1 ppm. Mass spec-
trum: m/z 587.68 [M + H]+. Found, %: C 71.58;
H 7.60; P 10.51. C35H44N2O2P2. Calculated, %:
C 71.65; H 7.56; P 10.56.
2,2-Dimethyl-5,11-diphenyl-4,6,10,12-tetraoxa-
5,11-diphospha-1,3,7,9(1,4)-tetrabenzenacyclodo-
decaphane (6). Bisphenol 2 or 1, 2 mmol, was added
to a solution of 2 mmol of compound 4 or 5, respec-
tively, in 50 mL of anhydrous toluene. The mixture
was heated for 4 h at 90‒95°C, the solvent was
removed under reduced pressure (water-jet pump), and
the residue was kept for 2 h under reduced pressure
(1 mm) at 90‒95°C. Yield 83%, unstable oily sub-
stance. IR spectrum, ν, cm–1: 1440 (P‒C), 1190 (O‒C).
The IR spectra were recorded on Perkin Elmer
IR-283 (KBr) and Specord 75IR spectrometers (film
between KBr plates). The 31P NMR spectra were
measured from solutions in CDCl3 on a Bruker AV 300
spectrometer (121.49 MHz) relative to 85% phos-
1
phoric acid. The H NMR spectra were recorded on
a Bruker AV 400 instrument (400 MHz) using CDCl3
as solvent and tetramethylsilane as reference. The mass
spectra were obtained on a Bruker Daltonics Ultraflex
TOF/TOF mass spectrometer (nitrogen laser,
λ 337 nm; positive ion detection). The progress of
reactions and the purity of products were monitored by
TLC on Silufol plates (hexane–dioxane, 3:1). Ultra-
pure silica gel (Merck Grade 7734, 60 Å, 70–
230 mesh) was used for column chromatography.
REFERENCES
1. Nifant’ev, E.E., Blokhin, Yu.I., and Ergashov, M.Ya.,
Dokl. Akad. Nauk, 1992, vol. 325, p. 73.
2. Blokhin, Yu.I., Gusev, D.V., Belsky, V.K., Stash, A.I., and
Nifantyev, E.E., Phosphorus, Sulfur Silicon Relat. Elem.,
1995, vol. 102, p. 143.
3. Blokhin, Yu.I., Galiaskarova, F.M., Gusev, D.V.,
Ergashov, M.Ya., Belsky, V.K., and Nifantyev, E.E.,
Phosphorus, Sulfur Silicon Relat. Elem., 1996, vol. 111,
p. 170.
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 52 No. 4 2016