New catalytic methods for the preparation of acetals from alcohols and aldehydes

Article abstract of DOI:10.1080/00397910600616628

The acetalization of aldehydes has been studied with ethyleneglycol, 3-chloro-1,2-propanediol, 1,2-propanediol, and 1,2,3-propanetriol using resin-D₇₂ catalyst in high yields under reflux and water separator conditions. The reaction is simple, efficient, and chemoselective and does not involve any other additive. Copyright Taylor & Francis Group, LLC.

Full text of DOI:10.1080/00397910600616628

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New Catalytic Methods for the Preparation of
Acetals from Alcohols and Aldehydes
a b
c
a
a
Yonghong Li
, Xiaojun Zhang , Tianrui Ren & Jiaju Zhou
a
State Key Laboratory of Biochemical Engineering, Institute of Process
Engineering, Chinese Academy of Sciences, Beijing, P. R. China
b
Graduate University of Chinese Academy of Sciences, Beijing, P. R. China
c
Central Research Institute of China Chemical Science and Technology
Beijing Grand AgroChem, LLC, Beijing, P. R. China
Version of record first published: 22 Aug 2006
To cite this article: Yonghong Li, Xiaojun Zhang, Tianrui Ren & Jiaju Zhou (2006): New Catalytic Methods for
the Preparation of Acetals from Alcohols and Aldehydes, Synthetic Communications: An International Journal
for Rapid Communication of Synthetic Organic Chemistry, 36:12, 1679-1685
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Synthetic Communications , 36: 1679–1685, 2006
Copyright # Taylor & Francis Group, LLC
ISSN 0039-7911 print/1532-2432 online
DOI: 10.1080/00397910600616628
New Catalytic Methods for the Preparation
of Acetals from Alcohols and Aldehydes
Yonghong Li
State Key Laboratory of Biochemical Engineering, Institute of Process
Engineering, Chinese Academy of Sciences, Beijing, P. R. China and
Graduate University of Chinese Academy of Sciences, Beijing,
P. R. China
Xiaojun Zhang
Central Research Institute of China Chemical Science and Technology
Beijing Grand AgroChem, LLC, Beijing, P. R. China
Tianrui Ren and Jiaju Zhou
State Key Laboratory of Biochemical Engineering, Institute of Process
Engineering, Chinese Academy of Sciences, Beijing, P. R. China
Abstract: The acetalization of aldehydes has been studied with ethyleneglycol,
3-chloro-1,2-propanediol, 1,2-propanediol, and 1,2,3-propanetriol using resin-D72
catalyst in high yields under reflux and water separator conditions. The reaction is
simple, efficient, and chemoselective and does not involve any other additive.
Keywords: Acetalization, aldehyde, catalyst
INTRODUCTION
[
1,2]
[3–5]
[6]
and steroid chemistry. In
Acetals areimportant insynthetic carbohydrate
[
the pharmaceutical, phytopharmaceutical, fragrance, and lacquer indus-
7]
[8]
[9]
[10]
tries, acetals are used as intermediates and end products. Acetalization is
one of the widely used synthetic methods for protecting aldehydes and
Received in Japan October 24, 2005
Address correspondence to Tianrui Ren, State Key Laboratory of Biochemical
Engineering, Institute of Process Engineering, Chinese Academy of Sciences,
Beijing 100080, China. E-mail: trren@home.ipe.ac.cn
1
679

1
680
Y. Li et al.
ketones in the course of the preparation of a variety of multifunctional
[
11]
complex organic molecules.
So far, several methods have been
developed for this purpose. Generally, acetalization reactions are carried out
by treatment of carbonyl compounds with alcohols in the presence of an
acid catalyst and proceed with azeotropic removal of water, using Dean–
Stark apparatus. Previously, the catalysts used in the acetalization reaction
were generally protonic acids, Lewis acids, and a number of transitional
[12–15]
metal complexes including Rh, Pd, and Pt.
Although good results
were obtained, the separation of the product from the catalyst system after
the reaction was still difficult, and the noble metal catalysts used were quite
[16]
expensive and usually unstable.
Therefore, the development of a
catalytic system that is stable, easily separable, and reusable has long been
awaited, and the increasing demand for safe industrial processes requires
and implementation of ecofriendly, solid, benign catalysts for value-added
acid-catalyzed reactions. We are surprise to find, however, resin-D , a sort
7
2
of strongly acidic macroporous adsorption cation exchanger–sulfonic acid
functionality resin, has little been used as a catalyst in this context. In this
article, we report our preliminary findings that this simple, inexpensive,
efficient, recyclable, and highly ecofriendly acid catalyst can be successfully
used in the acetalization reactions.
RESULTS AND DISCUSSION
To evaluate the influence of resin-D72 on the acetalization reactions, we
examined the reaction of furfural with 1,2-propanediol in toluene in the
presence of resin-D , using a water separator. Good results were obtained.
7
2
Cation-exchange resin-D72 is a copolymer of divinylbenzene (DVB) and
styrene; sulfonic acid is the active site (Brønsted acidity), which is the same
[
17,18]
as Amberlyst-15.
product. Unlike Amberlyst-15 (U.S.), it can be obtained easily and cheaply.
Resin-D , however, is a sort of commercial domestic
72
Unlike dry HCl, corrosive acid HF, saturated H SO , and p-TsOH, it can be
2
4
recycled, does not erode the apparatus, and separates the products easily, and
the reaction does not involve any other additive.
We also successfully carried out the resin-D -induced acetalization
7
2
reactions of other aldehydes with glycols or thiols, as shown in Table 1.
From the results of Table 1, it was observed that the use of resin-D72 as an
acid catalyst gives a high yield.
In conclusion, we have demonstrated that the rather cheap, readily
available, and user-friendly resin-D72 can be used as a new, simple, and
efficient acid catalyst for the acetalization reactions. It does not involve
additives, and the catalyst can be recycled without loss of activity. In
addition, its activity is even superior to that of the most widely used
catalyst, p-TsOH. Further investigation in optimizing the reaction conditions
is being actively pursed in our laboratory.

Acetals from Alcohols and Aldehydes
Table 1. Resin-D72-induced acetalization reactions
1681
Time
(h)
Yield
a
(%)
Entry
X
1
X
2
X
3
R
1
R
2
Cat.
Product
1
2
3
4
5
6
7
8
9
O
O
O
O
O
O
O
O
O
O
S
O
O
S
O
O
O
S
H
CH
3
D
D
D
72
72
72
5
5
3a
3b
3c
3d
3e
3f
85
82
78
93
90
87
83
73
78
90
89
85
80
84
91
H
H
H
H
CH
H
2
Cl
5
S
H
D72
5
O
O
O
O
S
O
O
O
O
O
S
CH
H
2
OH
Cl
D
D
72
72
5
CH
CH3
3
5
CH3
D72
5
3g
3h
3i
CH
CH
3
CH
H
2
D
D
72
72
5
3
5
1
1
1
1
1
1
0
1
2
3
4
5
S
CH3
H
H
D72
5
3j
O
O
O
S
O
O
O
O
S
H
CH
D
D
72
72
10
10
10
10
10
3k
3l
S
H
3
S
H
CH Cl
2
D72
D72
3m
3n
3o
S
H
H
H
S
S
H
D
72
a
Isolated yield based on aldehyde.
EXPERIMENTAL
The IR spectra were determined on a Bio-Rad Win-IR infrared spectrometer
1
by dispersing samples in KBr disks. H NMR spectra were measured on a
Bruker DPX300 NMR spectrometer with CDCl as solvent. Resin-D was
72
3
purchased from the Chemical Plant of Nankai University. Analytical
thin-layer chromatography (TLC) was performed on precoated plates
purchased from Qingdao Haiyang Chemical Co., Ltd. (silica GF254) using
[
19–21]
UV light. Partial products are already reported in the literature.
commercial available organic compounds were used with further purification,
Partial
˚
and solvents for the reactions were dried on 4-A molecular sieves before use.
General Procedure
In a general reaction procedure, a mixture of carbonyl compounds (10 mmol);
protecting groups glycols or thiols such as ethyleneglycol, 3-chloro-1,2-
-
propanediol, 1,2-propanediol, 1,2,3-propanetriol, and 1-hydroxyethane-2-thiol
11 mmol) and resin-D72 10% (w/w) in toluene (25 mL) was refluxed for
–10h, using a water separator. After the reaction was complete (TLC), the
(
5

1
682
Y. Li et al.
resin-D72 was separated by filtration and could be reused for the next run after
simple treatment. The toluene was removed under reduced pressure. The
product was obtained by distilling the residue under oil-pump reduced pressure.
2-Furan-2-yl-4-methyl-[1,3]dioxolane (3a). This compound was prepared in
the same manner as that described previously. This pure product (3a, isomers)
2
1
is a colorless liquid: 69–708C/1.73 KPa, C H O . IR (neat): n (cm ) 3124,
8
10 3
2
7
3
5
980, 2883, 1604, 1503, 1377, 1357, 1254, 1225, 1156, 1095, 1070, 1067,
1
46. H NMR (300 MHz, CDCl ): d 1.32 (d, J ¼ 6.12 Hz, 3H, OCHCH ),
3
3
.50 (m, 1H, OCH H ), 4.09 (m, 1H, OCH H ), 4.29 (m, 1H, OCHCH ),
a
b
a
b
3
.89 (s, 1H, CCHO ), 6.34 (m, 1H, CHCHO), 6.42 (m, 1H, CHCO), 7.41
2
(
OCH H ), 4.25 (m, 1H, OCH H ), 4.42 (m, 1H, CHCH O), 6.02
m, 1H, CHCHO); 1.38 (d, J ¼ 6.03 Hz, 3H, OCHCH ), 3.60 (m, 1H,
3
a
b
a
b
3
(
(
s, 1H, CCHO ), 6.34 (m, 1H, CHCHO), 6.47 (m, 1H, CHCO), 7.41
2
m, 1H, CHCHO) ppm.
4-Chloromethyl-2-furan-2-yl-[1,3]dioxolane (3b). This compound was
prepared in the same manner as that described previously. This pure
product (3b, isomers) is a pale yellow liquid: 129–1318C/1.86 KPa,
21
C H ClO . IR (neat): n (cm ) 3126, 2958, 2889, 1606, 1507, 1361, 1257,
8
9
3
1
1
232, 1154, 1094, 1013, 960, 747. H NMR (300 MHz, CDCl ): d 3.56
3
(
m, 1H, CH H Cl), 3.67 (m, 1H, CH H Cl), 3.94 (m, 1H, OCH H ), 4.12
a b a b a b
(
m, 1H, OCH H ), 4.40 (m, 1H, OCHCH Cl), 5.91 (s, 1H, CCHO ),
a b 2 2
6
3
4
6
.35 (m, 1H, CHCHCO), 6.43 (m, 1H, CHCO), 7.42 (m, 1H, CHCHO);
.60 (m, 1H, CH H Cl), 3.69 (m, 1H, CH H Cl), 4.10 (m, 1H, OCH H ),
.28 (m, 1H, OCH H ), 4.52 (m, 1H, OCHCH Cl), 6.07 (s, 1H, CCHO ),
a
b
a
b
a b
a
b
2
2
.37 (m, 1H, CHCHCO), 6.49 (m, 1H, CHCO), 7.42 (m, 1H, CHCHO) ppm.
2-Furan-2-yl-[1,3]oxathiolane (3c). This compound was prepared in the
same manner as that described previously. This pure product (3c) is a
2
1
yellow liquid: 85–88 8C/1.33 KPa, C H O S. IR (neat): n (cm ) 3121,
2
7
8 2
1
942, 2875, 1723, 1501, 1232, 1152, 1055, 1013, 968, 743. H NMR
(
300 MHz, CDCl ): d 3.20 (m, 2H, SCH CH ), 4.15 (m, 2H, OCH CH ),
3
2
2
2
2
6.11 (s, 1H, CHSO), 6.33 (m, 1H, CHCO), 6.45 (m, 1H, CHCHO), 7.42
(
m, 1H, CHCHO) ppm.
2-[1,3]Dithiolan-2-yl-furan (3d). This compound was prepared in the same
manner as that described previously. This pure product (3d) is an aurantium
2
1
liquid: 118–120 8C/0.66 KPa, C H OS . IR (neat): n (cm ) 3117, 2925,
1
7
8
2
1
585, 1499, 1421, 1276, 1171, 1147, 1010, 936, 851, 739. H NMR
(
SCH CH S), 5.62 (s, 1H, CHS ), 6.27–6.30 (m, 2H, OCHCHCHC), 7.36
300 MHz, CDCl ): d 3.26–3.33 (m, 2H, SCH CH S), 3.38–3.46 (m, 2H,
3
2
2
2
2
2
(
m, 1H, OCHCHCH) ppm.
(2-Furan-2-yl-[1,3]dioxolan-4-yl)-methanol (3e). This compound was
prepared in the same manner as that described previously. This pure
product (3e, isomers) is a colorless liquid: 162–1648C/1.20 KPa, C H O .
8
10 4

Acetals from Alcohols and Aldehydes
1683
2
IR (neat): n (cm ) 3437, 3126, 2931, 2889, 1723, 1504, 1363, 1230, 1155,
1
1
1
097, 884, 749. H NMR (300 MHz, CDCl ): d 2.45 (s, 1H, OH), 3.63–3.68
3
(m, 5H, CH CHCH OH), 5.90 (s, 1H, CHO ), 6.36 (m, 1H, OCHCHCHC),
2 2 2
6
.45 (m, 1H, OCHCHCHC), 7.43 (m, 1H, OCHCHCHC), 2.46 (s, 1H, OH),
.04–4.23 (m, 5H, CH CHCH OH), 6.04 (s, 1H, CHO ), 6.37 (m, 1H,
4
OCHCHCHC), 6.50 (m, 1H, OCHCHCHC), 7.45 (m, 1H, OCHCHCHC) ppm.
2
2
2
2-(5-Methyl-furan-2-yl)-[1,3]dioxolane (3f). This compound was prepared
in the same manner as that described previously. This pure product (3f) is a
2
1
colorless liquid: 74–758C/0.80 KPa, C H O . IR (neat): n (cm ) 3111,
2
8
10 3
1
955, 2890, 1726, 1616, 1565, 1383, 1349, 1219, 1110, 945, 791. H NMR
(300 MHz, CDCl ): d 2.30 (s, 3H, CH CO), 3.97–4.05 (m, 2H,
OCH CH O), 4.12–4.16 (m, 2H, OCH CH O), 5.84 (s, 1H, CHO ), 5.93
3
3
2
2
2
2
2
(
m, 1H, CH CCHCH), 6.33 (d, J ¼ 3.12 Hz, 1H, CH CCHCH) ppm.
3
3
4-Methyl-2-(5-methyl-furan-2-yl)-[1,3]dioxolane (3g). This compound was
prepared in the same manner as that described previously. This pure product
(
3g, isomers) is a yellow liquid: 97–998C/0.80 KPa, C H O . IR (neat):
9
12 3
2
n (cm ) 3438, 2981, 2938, 1724, 1678, 1565, 1521, 1382, 1187, 967, 794.
1
1
H NMR (300 MHz, CDCl ): d 1.32 (d, J ¼ 6.12 Hz, 3H, OCHCH ), 2.30
3
3
(
(
(
(
(
(
s, 3H, CH CO), 3.50 (m, 1H, OCH H ), 4.09 (m, 1H, OCH H ), 4.28
3 a b a b
m, 1H, OCHCH ), 5.82 (s, 1H, CCHO ), 5.93 [m, 1H, CHC(CH )O], 6.30
3
2
3
d, J ¼ 3.09 Hz, 1H, CHCO), 1.39 (d, J ¼ 6.06 Hz, 3H, OCHCH ), 2.30
3
s, 3H, CH CO), 3.61 (m, 1H, OCH H ), 4.23 (m, 1H, OCH H ), 4.42
3
a
b
a b
m, 1H, OCHCH ), 5.95 (s, 1H, CCHO ), 5.91 [m, 1H, CHC(CH )O], 6.35
3
2
3
d, J ¼ 3.12 Hz, 1H, CHCO) ppm.
4-Chloromethyl-2-(5-methyl-furan-2-yl)-[1,3]dioxolane(3h).Thiscompound
was prepared in the same manner as that described previously. This pure
product (3h, isomers) is a pale yellow liquid: 129–1318C/1.86 KPa,
2
C H ClO . IR (neat): n (cm ) 3492, 2957, 2887, 1728, 1565, 1431, 1351,
1
9
11
3
1
1
220, 1174, 1093, 1021, 946, 792. H NMR (300 MHz, CDCl ): d 2.29
3
(
(
(
(
(
(
m, 3H, CH C), 3.56 (m, 1H, CH H Cl), 3.64 (m, 1H, CH H Cl), 3.93
3 a b a b
m, 1H, OCH H ), 4.12 (m, 1H, OCH H ), 4.30 (m, 1H, OCHCH Cl), 5.84
2
a
b
a
b
s, 1H, CCHO ), 5.93 (m, 1H, CHCHCO), 6.32 (m, 1H, CHCO); 2.30
2
m, 3H, CH C), 3.60 (m, 1H, CH H Cl), 3.67 (m, 1H, CH H Cl), 4.09
a b
3
a
b
m, 1H, OCH H ), 4.30 (m, 1H, OCH H ), 4.52 (m, 1H, OCHCH Cl), 5.99
a
b
a
b
2
s, 1H, CCHO ), 5.95 (m, 1H, CHCHCO), 6.38 (m, 1H, CHCO) ppm.
2
2-(5-Methyl-furan-2-yl)-[1,3]oxathiolane (3i). This compound was prepared
in the same manner as that described previously. This pure product (3i) is an
2
1
aurantium liquid: 120–121 8C/1.20 KPa, C H O S. IR (neat): n (cm
2
)
943, 2873, 1559, 1385, 1222, 1162, 1056, 1021, 966, 947, 788. H NMR
8
10 2
1
(
300 MHz, CDCl ): d 2.29 (s, 3H, CH CO), 3.07–3.27 (m, 2H, SCH CH ),
3
3
2
2
3
CHC(CH )O], 6.34 (m, 1H, CHCO) ppm.
.98–4.34 (m, 2H, OCH CH ), 6.05 (s, 1H, CHSO), 5.92 [m, 1H,
2 2
3

1
684
Y. Li et al.
2-[1,3]Dithiolan-2-yl-5-,ethyl-furan (3j). This compound was prepared in
the same manner as that described previously. This pure product (3j) is an
2
1
aurantium liquid: 132–133 8C/0.80 KPa, C H OS . IR (neat): n (cm
)
105, 2923, 1607, 1556, 1422, 1277, 1217, 1121, 1021, 997, 965, 789.
8
10
2
3
1
H NMR (300 MHz, CDCl ): d 2.27 (s, 3H, CH CO), 3.26–3.34 (m, 2H,
3
3
SCH CH S), 3.38–3.46 (m, 2H, SCH CH S), 5.59 (s, 1H, CHS ), 5.86
2
2
2
2
2
(
m, 1H, CH CCHCH), 6.17 (d, 1H, CH CCHCH) ppm.
3 3
2-Thiophen-2-yl-[1,3]dioxolane (3k). This compound was prepared in the
same manner as that described previously. This pure product (3k) is a
2
1
colorless liquid: 88–89 8C/0.66 KPa, C H O S. IR (neat): n (cm ) 3106,
2
7
8 2
1
969, 2889, 1674, 1545, 1442, 1391, 1331, 1086, 943, 838, 712. H NMR
(
300 MHz, CDCl ): d 3.96–4.15 (m, 4H, OCH CH O), 6.11 (s, 1H, CHO ),
3
2
2
2
6.98 (m, 1H, CHCHCHC), 7.16 (m, 1H, CHCHCHC), 7.3 (m, 1H,
SCHCHCHC) ppm.
-Methyl-2-thiophen-2-yl-[1,3]dioxolane (3l). This compound was prepared in
the same manner as that described previously. This pure product (3l, isomers) is
4
2
1
a colorless liquid: 131–1338C/0.66KPa, C H O S. IR (neat): n (cm ) 3107,
8
10 2
2
977, 2932, 2880, 1545, 1444, 1382, 1330, 1212, 1089, 1002, 971, 837, 711.
1
H NMR (300MHz, CDCl ): d 1.33 (d, 3H, J ¼ 5.97Hz, OCH CH ), 3.50
3
a
3
(
(
m, 1H, OCH H ), 4.10 (m, 1H, OCH H ), 4.33 (m, 1H, OCHCH ), 6.10
a b a b 3
s, 1H, CCHO ), 6.98 (m, 1H, CHCHO), 7.16 (m, 1H, CHCS), 7.33 (m, 1H,
2
CHCHO), 1.39 (d, J ¼ 5.94Hz, 3H, OCHCH ), 3.62 (m, 1H, OCH H ), 4.32
3
a b
(
(
m, 1H, OCH H ), 4.42 (m, 1H, OCHCH ), 6.24 (s, 1H, CCHO ), 7.00
a
b
3
2
m, 1H, CHCHO), 7.18 (m, 1H, CHCS), 7.35 (m, 1H, CHCHO) ppm.
4-Chloromethyl-2-yl-[1,3]dioxolane (3m). This compound was prepared in
the same manner as that described previously. This pure product (3m,
isomer) is a pale yellow liquid: 110–112 8C/0.40 KPa, C H ClO S. IR
8
9
2
2
1
neat): n (cm ) 3108, 2955, 2886, 1545, 1442, 1394, 1332, 1214, 958, 844,
(
1
7
13. H NMR (300 MHz, CDCl ): d 3.53–3.72 (m, 2H, CH H Cl), 3.93
3 a b
(
m, 1H, OCH H ), 4.12 (m, 1H, OCH H ), 4.32 (m, 1H, OCHCH Cl), 6.11
a b a b 2
(
CHCS), 7.35 (m, 1H, CHCHS), 3.53–3.72 (m, 2H, CH H Cl), 4.14
s, 1H, CCHO ), 6.99 (m, 1H, CHCHCS), 7.18 (d, J ¼ 0.873 Hz 1H,
2
a
b
(
(
m, 1H, OCH H ), 4.30 (m, 1H, OCH H ), 4.50 (m, 1H, OCHCH Cl), 6.28
a b a b 2
s, 1H, CCHO ), 7.00 (m, 1H, CHCHCS), 7.20 (d, J ¼ 0.927 Hz 1H,
2
CHCS), 7.36 (m, 1H, CHCHS) ppm.
2-Thiophen-2-yl-[1,3]oxathiolane (3n). This compound was prepared in the
same manner as that described previously. This pure product (3n) is a pale
2
1
yellow liquid: 108–1108C/0.40 KPa, C H OS . IR (neat): n (cm ) 3104,
7
8
2
2
974, 2941, 2872, 1708, 1438, 1372, 1315, 1266, 1057, 963, 855, 709.
1
H NMR (300 MHz, CDCl ): d 3.17 (m, 1H, SCH H CH ), 3.30 (m, 1H,
2
3
a
b
SCH H CH ), 3.98 (m, 1H, OCH H CH ), 4.41 (m, 1H, OCH H CH ), 5.31
a
b
2
a
b
2
a
b
2
(s, 1H, CHSO), 6.95 (m, 1H, CHCS), 7.14 (m, 1H, CHCHS), 7.31 (m, 1H,
CHCHS) ppm.

Acetals from Alcohols and Aldehydes
1685
2-Thiophen-2-yl-[1,3]dithiolane (3o). This compound was prepared in the
same manner as that described previously. This pure product (3o) is a
2
1
colorless liquid: 131–133 8C/0.40 KPa, C H S . IR (neat): n (cm ) 3101,
3
7
8 3
1
070, 2922, 1430, 1270, 1221, 1118, 1085, 978, 853, 747. H NMR
(300 MHz, CDCl ): d 3.28–3.38 (m, 2H, SCH CH S), 3.43–3.52 (m, 2H,
SCH CH S), 5.92 (s, 1H, CHS ), 6.87–6.89 (m, 1H, SCHCHCHC), 7.06
3
2
2
2
2
2
(m, 1H, SCHCHCHC), 7.23 (m, 1H, SCHCHCH) ppm.
ACKNOWLEDGMENTS
The present work was financially supported by the National 973 Program of
China (Contract No. 2003CB114400).
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