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BOUKHOBZA et al., Orient. J. Chem., Vol. 30(1), 255-259 (2014)
Synthesis of Tri Decyl Phosphate (TDP)
C30H63O4P, nD20 = 1.452.
cm-1; and the PO-H (ν = 2300 – 2400 cm-1)8.
31P NMR: δ/H3PO4 (ppm) = -1.70.
The acid nature of dialkylphosphates
1H NMR: δ/TMS (ppm) = 0.90(t, 9H, CH3), 1.26(m, was confirmed by the titration. The titration curves
48H, CH2), 3.97(m, 6H, CH2O-P)
IR: ν (cm-1) = 894 et 1028 (P-O-C), 1262 (P=O), All the results of these analyses have shown that the
presented one slope shift corresponds to pH= 5.81.
1378 (CH (CH3)), 1466 (CH (CH3 & CH2)), 2854 & products of the reaction of alcohol with phosphorus
2923 (CH ( CH3 & CH2)).
tr (GPC)(min): 10.28.
oxychloride, obtained under micro-wave irradiation,
were identical to those obtained with the classic
method of heating. In fact, the 31P NMR has shown
Synthesis of Tri [4-(1,1,3,3,-Tetra-methylbutyl) the formation of trialkyl-phosphates and the acid
phényl] Phosphate (TOPPA)
C42H63O4P
dialkyl-phosphoric acids according to Schemes 1
and 2.
31P NMR: δ/H3PO4 (ppm) = -16.1.
1H NMR: δ/TMS (ppm) = 0.71 (s, 27H, CH3), 1.33 (s,
Different trialkylphosphates are synthesized
18H, CH2), 1.68 (s, 6H, CH2), 6.76 (d, 6H, CHmeta
,
under microwave irradiations and by classic heating,
J3 H-H = 8.68 Hz), 7.24 (d, 6H, CHortho, J3 H-H = and this in presence or in absence of pyridine. The
9.57Hz).
yields and the different operating conditions are
IR:ν (cm-1) = 825 et 960 (P-O-C), 1165 (PO-C arom.), mentioned in Table 1.
1200 (al. P=O), 1360 (CH (CH3)), 1425 (CH (CH3 &
CH2), C=C & C-C arom.), 2850 et 2945 (CH ( CH3
& CH2)).
The powers and the times of irradiation are
fixed to obtain temperature near of the one applied
*δ, chemical shift; ν, wave number; s, singulet; d, in the classic heating (80-97°C), recommended for
doublet; t, triplet; m, multiplet.
the synthesis of alkylphosphates9-11
.
RESULTS AND DISCUSSION
The comparative study of the results of
synthesis under microwave irradiation has shown
Reactional mixtures obtained under microwave that in presence of pyridine the synthesis yields were
irradiationswereconfirmedbyvarioustechniques weaker than those obtained in absence of pyridine.
of analyses6.
The 31P NMR has shown the presence
In absence of pyridine, the synthesis yields
of two important signals corresponding to tri obtained by classic method of heating were higher
[4-(1,1’,3,3’,-tetramethylbutyl)phenyl] phosphate to those obtained under microwave irradiation.
(TOPPA (δ = -16.10 ppm )) and to di [4-(1,1’,3,3’,-
tetramethylbutyl)phenyl] phosphoric acid (DOPPA (δ
Nevertheless, the yields in the latter cases
= -9.11 ppm )). Small signal corresponding to the were lightly superior, although no precaution was
secondary product (the pyrophosphates (δ = -12 taken to avoid the secondary reactions (scheme
ppm) was also observed.
II). The short times of synthesis under microwave
irradiation have not favored the secondary reactions,
1H NMR confirmed the formation of even to high temperatures.
trialkylphosphates and the acid dialkylphosphoric
acids with characteristic signals corresponding to
Besides, the obtained yields under
the protons CH3(δ = 0.9 ppm), (CH2)n (δ = 1.2 - 1.6 microwave irradiation were lightly inferior to those
ppm), CH2-O-P (δ = 3.8 - 4.1 ppm), P-O-H (δ = 7 - 8 obtained under classic heating. The difference can
ppm) and aromatic C-H from d = 7 ppm.
be explained by the higher reduction of reaction time,
from some seconds to 2h.
The infrared spectra have presented
absorption corresponding to trialkylphosphates and
the acid dialkylphosphoric acids groups: P-OC and
P-OH (ν = 1030-1040 cm-1); P=O (ν = 1260 – 1265
CONCLUSION
The products of the reaction of alcohols