CHEMISTRY OF DIOXACYCLANES: XI.
259
b. A mixture of 19.5 g of aldehyde IIb, 22.5 g of
diol Ib, 50 ml of toluene, and 0.06 g (0.3 wt% with
respect to aldehyde) of TsOH was heated with azeo-
tropic distillation of the reaction water under the
above conditions and then washed with 5% potassium
carbonate and water, dried with K CO , the solvent
CH=CH). Compounds IIIh and IIIj were synthesized
in a similar way (see table).
2-(5,6-Epoxynorbornan-2-yl)-1,3-dioxolane
(IVb). To a mixture of 31.6 g of compound IIIb and
50 ml of chloroform, 30.4 g of 50% peracetic acid
was added with stirring at 18 20 C. The mixture was
stirred at that temperature for an additional 1.5 2 h
and then treated with 5% aqueous sodium bicarbonate,
2
3
was removed, and the residue was distilled in a
vacuum to isolate 28.9 g (76%) of compound IIIf, bp
2
4
0
20
1
10 112 C (1 mm), d 1.0592, nD 1.4835. Com-
washed with water, and dried with MgSO . The sol-
pounds IIId and IIIe were synthesized in a similar
way (see table).
4
vent was removed in a vacuum to leave compound
1
IVb (see table). H NMR spectrum, , ppm: 0.70
c. A mixture of 33.6 g of 5-norbornene-2-carbox-
aldehyde dimethyl acetal (IIf), 29.0 g of diol Ib, 0.3 g
2.68 group of signals (9H, carboring), 2.87 d (2H,
oxirane 2CH), 3.00 4.20 m (4H, CH CH O), 4.60 d
(1/2H, trans-OCHO, J 6 Hz), 4.79 d (1/2H, cis-
OCHO, J 6 Hz). Compound IVa was synthesized in a
similar way.
2
2
(
0.9 wt% with respect to IIf) of TsOH was heated
with azeotropic distillation of the methanol formed.
After cooling to room temperature, the reaction mix-
ture was washed with 2% aqueous sodium hydroxide
and water. The aqueous layer was treated with toluene,
the extracts were combined with the organic layer,
4
-(2,3-Dibromopropoxymethyl)-2-(trichloro-
methyl)-1,3-dioxolane (IVc). Bromine, 15 g, was
added with stirring to a mixture of 23.5 g of com-
dried with MgSO , the solvent was removed, and the
4
pound IIIg and 110 ml of CCl at 10 to 5 C. The
4
residue was distilled in a vacuum to isolate 39.3 g
mixture was stirred for an additional 1.5 3 h, washed
with 5% NaOH and water, the aqueous layer was
2
4
0
(
1
79%) of compound IIIf, bp 110 111 C (1 mm), d
.0672, n2 1.4840.
0
D
treated with CCl , the organic layers were combined,
4
washed with water, and dried with CaC . The solvent
was removed, and the residue was distilled in a
1
2
4
-(2-Propenyloxy)methyl-2-trichloromethyl-1,3-
dioxolane (IIIg). A mixture of 79.3 g of diol Ib,
06 g of aldehyde IIe, 1.0 g (0.9 wt% with respect to
vacuum to obtain 27.8 g (73%) of compound IVg (see
1
1
table). IR spectrum, , cm : 570, 550, 810, 960, 1100,
IIe) of TsOH, and 100 ml of toluene was stirred with
azeotropic distillation of the reaction water over the
course of 12 h. After cooling to room temperature, the
mixture was neutralized with 5% aqueous potassium
carbonate, the aqueous layer was extracted with to-
luene, the extracts were combined with the organic
layer, washed with water, dried with K CO , the sol-
1
220, 1360, 2800.
4-(2-Bromo-2-propenyloxymethyl)-2-trichloro-
methyl-1,3-dioxolane (IVd). a. Powdered KOH,
17.4 g, was added in portions to a mixture of 126.4 g
of compound Ig and 100 ml of dioxane. The mixture
was stirred for 3 4 h under reflux. The organic layer
was separated, the aqueous layer was treated with
ether, the combined organic solutions were dried with
2
3
vent was removed, and the residue was distilled in a
vacuum to isolate compound IIIg (see table). H
1
NMR spectrum, , ppm: 3.25 4.50 w.m (7H, CH2
MgSO ; the solvents were removed, and the residue
4
OCH CHCH O), 4.68 d (1/2H, trans-OCHO, J 7 Hz),
was distilled in a vacuum to obtain compound IVd
2
2
1
4
.80 d (1/2H, cis-OCHO, J 7 Hz), 5.30 m (2H,
(see table). IR spectrum, , cm : 650, 760, 910, 980,
CH =C), 5.90 m (1H, CH=C).
1100, 1169, 1320, 1620, 1280.
2
b. A mixture of 44.3 g of aldehyde IIe, 61.8 g of
-(2-bromo-2-propenyloxy)-1,2-epoxypropane, 50 ml
of toluene, and 3.9 g (0.9 wt % with respect to com-
2
-(3-Cyclohexenyl)-4-(propoxymethyl)-1,3-di-
oxolane (IIIi). A mixture of 33 g of aldehyde IIa,
5.6 g of diol Ic, 70 ml of toluene, and 0.1 g
0.3 wt% with respect to compound IIa) of KU-2 was
3
4
(
pound IIe) of H SO (d 1.84) was refluxed for 12 h,
2
4
cooled to 18 20C, and washed with 5% sodium bi-
carbonate and water. The aqueous layer was treated
with toluene, combined with the organic layer,
stirred at 130C for 5 h with azeotropic distillation of
the water formed, after which KU-2 was filtered off,
the solvent was removed, and the residue was vacuum-
distilled to isolate 51.6 g (76%) of compound IIIi.
The reaction progress was controlled by GLC. H
NMR spectrum, , ppm: 0.95 1.00 group of signals
washed with water, and dried with MgSO ; the sol-
4
1
vent was removed, and the residue was distilled in a
vacuum to obtain 15.6 g (20%) of compound IVd, bp
20
20
1
40 142 C (2 mm), d4 1.6288, nD 1.5164.
(
7H, CH CH CH ), 1.25 2.15 m (7H, CH OCH CH
3 2 2 2 2
CH ), 3.15 4.25 m (3H, CH O, CHO), 4.50 d (1/2H,
trans-OCHO), 4.60 d (1/2H, cis-OCHO), 5.45 m (2H,
2-(2,3-Dichlorobicyclo[3.2.1]oct-3-en-6-yl)-1,3-
dioxolane (IVf). Chloroform, 44.96 g, was added
2
2
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 74 No. 2 2004