PHOTOCATALYTIC SYNTHESIS OF 1,3-DIOXACYCLANES FROM DIOLS AND PRIMARY
1713
FFAP, 30 m × 0.32 mm, 0.25 µm; Analytical Science
30 m × 0.32 mm ID-BPS, 0.5 µm).
102 (3) [M]+, 101 (100), 55 (91), 71 (19), 41 (7),
43 (6).
Commercial reagents: ethylene glycol, 1,4-
butanediol, 1,5-pentanediol, methanol, and ethanol
were preliminary distilled prior to experiments by
procedures [12]. Crystal hydrate FeCl3·6H2O was used
as received. Nitrite NaNO2 was prepared by thermal
decomposition of sodium nitrate.
1,3-Dioxocane (3с). Yield 23.8 g (41%), colorless
1
fluid, bp 153°С [5]. Н NMR spectrum, δ, ppm: 1.49
m (2Н, С6Н2), 1.71 m (4Н, С5,7Н2), 3.69 m (4Н,
С4,8Н2), 4.81 d (2Н, С2Н2, J 6.8 Hz). 13С NMR
spectrum, δ, ppm: 23.20 (С6), 30.40 (С5,7), 69.10 (С4,8),
95.70 (С2). Mass spectrum, m/z (Irel, %): 116 (4) [M]+,
115 (100), 69 (95), 85 (63), 41 (44), 43 (41).
Photocatalytic synthesis of 1,3-dioxacyclanes.
General procedure. The synthesis of cyclic acetals
was performed on a photocatalytic installation Photo
Catalytic Reactor Lelesil Innovative Systems with a
quartz reactor of 250 mL capacity (Strohmeier
photoreactor equipped with a magnetic stirrer). In the
flask of the reactor was charged 6.3 mmol (1.70 g) of
FeCl3·6H2O, 6.3 mmol (0.44 g) of sodium nitrite, and
500 mmol of primary alcohol (20 mL of methanol 1b,
30 mL of ethanol 2b), and the reaction mixture was
stirred till the formation of a homogeneous solution
(nitrogen oxides liberation occurred). Then 500 mmol
of an appropriate diol was charged (30 g of ethylene
glycol 1а, 45 g of 1,4-butanediol 2а, 52 g of 1,5-
pentanediol 3а). The reactor was attached to the
installation in keeping with the instruction of the
producer. The radiation source is a mercury lamp of
medium pressure of the power 250 W. The radiation
spectral composition by energy is as follows: 48% of
UV range, 43% of visible range, 9% of IR range.
Spectral interval: 186–1368 nm. The light beam
reached the reaction system passing through a water
layer kept at a controlled temperature (20–50°C).
Photoactivation time: 6–24 h. On completing the
reaction the product was extracted in ethyl ether. The
upper organic layer was separated on a separatory
funnel, dried with anhydrous sodium sulfate, after
distilling off ethyl ether the residue was subjected to
fractional distillation.
2-Methyl-1,3-dioxolane (4c). Yield 29.5 g (67%),
1
colorless fluid, bp 87°С [5]. Н NMR spectrum, δ,
ppm: 1.32 d (6Н, СН3, J 5.4 Hz), 3.92 m (4Н, С4,5Н2),
4.99 q (2Н, С2Н2, J 5.4 Hz). 13С NMR spectrum, δ,
ppm: 18.60 (С6), 64.20 (С4,5), 100.20 (С2). Mass
spectrum, m/z (Irel, %): 88 (2) [M]+, 87 (13), 73 (100),
58 (22), 45 (40), 43 (45).
2-Methyl-1,3-dioxepane (5с). Yield 28.4 g (49%),
1
colorless fluid, bp 162°С [5]. Н NMR spectrum, δ,
ppm: 1.33 d (6Н, СН3, J 5.4 Hz), 1.59 m (4Н, С5,6Н2),
3.58 m (4Н, С4,7Н2), 4.81 q (2Н, С2Н2, J 5.4 Hz). 13С
NMR spectrum, δ, ppm: 20.50 (С8), 28.90 (С5,6), 67.40
(С4,7), 99.70 (С2). Mass spectrum, m/z (Irel, %): 116 (2)
[M]+, 101 (100), 55 (87), 71 (18), 41 (7), 43 (7).
2-Methyl-1,3-dioxocane (6с). Yield 22.7 g (35%),
1
colorless fluid, bp 167°С [5]. Н NMR spectrum, δ,
ppm: 1.35 d (6Н, СН3, J 5.4 Hz), 1.45–1.49 m (2Н,
С6Н2), 1.61–1.63 m (4Н, С5,7Н2), 3.71–3.74 m (4Н,
С4,8Н2), 4.68 q (2Н, С2Н2, J 5.4 Hz). 13С NMR
spectrum, δ, ppm: 19.60 (С9), 23.20 (С6), 29.20 (С5,7),
68.50 (С4,8), 99.50 (С2). Mass spectrum, m/z (Irel, %):
130 (2) [M]+, 115 (100), 69 (91), 85 (59), 41 (46),
43 (45).
ACKNOWLEDGMENTS
Structural study was carried out on the equipment
of the Center of Joint Usage “Chemistry” of the
Institute of Organic Chemistry of Ural Branch of the
Russian Academy of Sciences.
1,3-Dioxolane (1c). Yield 26.3 g (71%), colorless
1
fluid, bp 75°С [5]. Н NMR spectrum, δ, ppm: 3.79 m
(4Н, С4,5Н2), 4.85 d (2Н, С2Н2, J 6.4 Hz). 13С NMR
spectrum, δ, ppm: 64.50 (С4,5), 95.20 (С2). Mass
spectrum, m/z (Irel, %): 74 (6) [M]+, 73 (100), 45 (30),
44 (64), 43 (21), 29 (44), 15 (21).
REFERENCES
1. Ding, D., Pan, X., Zhang, Z., Li, N., Zhu, J., and Zhu, X.,
Polymer. Chem., 2016, vol. 7, p. 5258. doi 10.1039/
C6PY01061J
2. Vanparijs, N., Nuhn, L., and De Geest, B.G., Chem.
Soc. Rev., 2017, vol. 46, p. 1193.
1,3-Dioxepane (2с). Yield 27.9 g (55%), colorless
1
fluid, bp 141°С [5]. Н NMR spectrum, δ, ppm: 1.61
m (4Н, С5,6Н2), 3.68 m (4Н, С4,7Н2), 4.79 d (2Н, С2Н2,
J 6.6 Hz). 13С NMR spectrum, δ, ppm: 30.10 (С5,6),
67.20 (С4,7), 94.70 (С2). Mass spectrum, m/z (Irel, %):
3. Danilov, A.M., Chem. Technol. Fuels Oils, 2014,
vol. 50, p. 406. doi 10.1007/s10553-014-0540-2
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 54 No. 11 2018