Molecules 2016, 21, 170
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(2,2-Dimethyl-1,3-dioxolan-4-yl)methyl octanoate (
1
) Liquid at RT, m.p. « ´25 ˝C; 1H-NMR (400 MHz)
4.36–3.44 (m, 4H), 2.35 (td, J = 7.5, 2.2 Hz, 2H), 1.63 (tq, J = 10.6, 6.8, 5.2 Hz, 2H), 1.44 (t, 2H), 1.37 (t, 2H),
1.29 (dtq, J = 13.8, 9.0, 5.0, 4.6 Hz, 9H), 0.88 (t, J = 6.4 Hz, 3H); 13C-NMR (CDCl3, 100 MHz) (ppm):
173.39, 109.51, 77.38, 69.93, 65.52, 33.79, 31.31, 28.73, 28.57, 26.33, 25.05, 24.56, 22.25, 13.71; GC-MS
(relative intensity, 70 eV) m/z: 83 (10), 55 (10), 69 (11), 41 (11), 116 (12), 41 (14), 116 (15), 244 (15), 43 (18),
130 (19), 117 (20), 284 (20), 131 (21), 55 (23), 129 (25), 127 (30), 57 (31), 101 (32), 43 (35), 101 (37), 243 (100),
258 ([M]+, <1%); IR (wavenumber cm´1; Transmittance %): 3458; 70, 2930; 52, 1741; 51, 1384; 61, 1164;
63, 1050; 73, 700; 80.
(2,2-Dimethyl-1,3-dioxolan-4-yl)methyl dodecanoate (2
) m.p. = 40–48 ˝C; 1H-NMR (400 MHz) 4.38–3.42
(m, 4H), 2.34 (td, J = 7.6, 3.1 Hz, 2H), 1.63 (td, J = 7.3, 4.2 Hz, 3H), 1.44 (d, J = 4.8 Hz, 2H), 1.38
(d, J = 2.9 Hz, 2H), 1.26 (s, 18H), 0.88 (t, J = 6.6 Hz, 3H); 13C-NMR (100 MHz): 173.36, 109.53, 76.10,
69.98, 64.88, 33.85, 33.28, 31.61, 29.30, 29.15, 29.03, 28.95, 28.83, 26.40, 25.11, 24.61, 22.39, 13.82; GC-MS
(relative intensity, 70 eV) m/z: 83 (3), 85 (3), 185 (3), 213 (3), 41 (5), 71 (5), 171 (5), 55 (6), 183 (7),
57 (8), 129 (9), 116 (12), 43 (15), 300 (18), 101 (21), 299 (100), 314 ([M]+, <1%); IR (wavenumber cm´1
;
Transmittance %) 3292; 20, 2920; 0, 1739; 1, 1469; 7, 1418; 20, 1380; 14, 1208; 11, 1183; 10, 1104; 15, 1048;
12, 992; 31, 943; 37, 849; 41, 757; 13, 720; 25.
(2,2-Dimethyl-1,3-dioxolan-4-yl)methyl palmitate (
6.1 Hz, 2H), 2.36 (t, J = 7.5 Hz, 2H), 1.64 (s, 3H), 1.45 (t, 3H), 1.38 (t, 3H), 1.28 (d, J = 6.8 Hz, 34H), 0.89
t, J = 6.2 Hz, 3H); 13C-NMR (100 MHz): 173.63, 109.52, 73.37, 66.07, 64.87, 33.84, 31.63, 29.38, 29.15,
3
) m.p. = 55 ˝C; 1H-NMR (400 MHz) 4.11 (dt, J = 11.5,
(
29.06, 29.06, 29.06, 29.06, 28.95 28.95, 28.83, 26.40, 26.22, 25.10, 24.62, 22.41, 13.83; GC-MS (relative
intensity, 70 eV) m/z: 171 (7), 55 (8), 57 (10), 116 (12), 129 (12), 43 (17), 101 (21), 356 (24), 355 (100), 370
([M]+, <1%); IR (wavenumber cm´1; Transmittance %) 3234; 30, 2917; 6, 1730; 9, 1469; 13, 1382; 14,
1220; 13, 1048; 15, 849; 27, 757; 12, 667; 35, 516; 48.
˝
(2,2-Dimethyl-1,3-dioxolan-4-yl)methyl stearate (4 δ 4.38–3.53 (m, 5H),
) m.p. = 54 C;1H-NMR (400 MHz)
2.42–2.29 (m, 2H), 1.45 (dt, J = 2.5, 0.7 Hz, 2H), 1.39 (h, J = 0.7 Hz, 2H), 1.27 (s, 32H), 0.97–0.82 (m, 3H);
13C-NMR (100 MHz) 173.36, 109.53, 77.36, 76.88, 76.72, 76.23, 76.09, 73.39, 69.99, 66.07, 64.23, 63.04, 33.86,
31.64, 29.41, 29.17, 29.07, 28.97, 28.84, 26.40, 25.12, 24.63, 22.41, 13.83; GC-MS (relative intensity, 70 eV)
m/z: 69 (3), 83 (3), 85 (3), 267 (3), 297 (4), 341 (4), 385 (4), 41 (5), 71 (5), 185 (5), 55 (6), 171 (7), 340 (7),
57 (8), 116 (9), 129 (11), 43 (14), 101 (17), 384 (25), 383 (100), 398 ([M]+, <1%); IR (wavenumber cm´1
;
Transmittance %) 3234; 26, 2916; 0, 2890; 0, 1730; 2, 1472; 1, 1418; 23, 1381; 10, 1292; 25, 1216, 3; 1180; 5,
1048; 6, 991; 36, 944; 42, 848; 33, 758; 3, 719; 17, 667; 52, 515; 60.
3.4. General Procedure for Synthesis of Fatty Acid Glycerol Formal esters (FAGE)
The FFA (2.0 g), glycerol formal (GlyF: 1.5 molar equivalent respect to the FFA) and
p-toluene-sulfonic acid (5% w/w respect of the weight of the FFA) wer˝e charged in a conventional
round bottom flask with a magnetic stirrer. The mixture was heated at 60 C and stirred vigorously for
4 h. The reaction was quenched by neutralizing the acid catalyst with saturated solution of sodium
carbonate then filtered. The liquid phase was collected in a separatory funnel and partitioned between
chloroform and water (3
ˆ
20 mL). The organic layer was dried over sodium sulfate, filtered and the
solvent eliminated using a rotary evaporator. The sample was stored in a glass vial Table 2 summarizes
the experimental conditions and the results of reactions between GlyF and the FFAs.
(1,3-Dioxolan-4-yl)methyl octanoate (
2.35 (ddd, J = 9.8, 6.6, 2.2 Hz, 2H), 1.63 (depth, J = 11.1, 3.5 Hz, 2H), 1.44 (s, 2H), 1.29 (d, J = 6.0 Hz, 9H),
0.92–0.85 (m, 3H); 13C-NMR (100 MHz)
178.88, 95.12, 77.38, 68.26, 63.03, 33.95, 33.84, 31.32, 28.75,
5 δ 4.35–3.41 (m, 4H),
) Liquid at RT; 1H-NMR (400 MHz, CDCl3)
δ
28.72, 28.58, 24.57, 24.39, 22.27, 13.73; GC-MS (relative intensity, 70 eV) m/z: 69 (5), 83 (5), 116 (5), 84 (6),
109 (7), 42 (8), 58 (8), 73 (8), 126 (8), 128 (8), 98 (9), 103 (10), 45 (11), 87 (11), 145 (12), 146 (15), 41 (21),
43 (21), 55 (26), 86 (68), 57 (77), 127 (100), 230 ([M]+, <1%); IR (wavenumber cm´1; Transmittance %)
3558; 77, 2930; 32, 2858; 44, 1739; 32, 1492; 68, 1384; 61, 1166; 44, 1045; 55, 942; 64,757; 56.