P. S. Kishore et al. / Tetrahedron Letters 47 (2006) 429–431
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H SO catalyzed reaction (in this case a 64 h reaction
References and notes
2
4
time was required), the turn over frequencies are consid-
erably higher for the HPA catalyzed reactions. As HPA
is an active catalyst with higher Brønsted acidity, the
same synthetic procedure can be employed for the syn-
thesis of other chloro alkyl ethers. For example, di-
ethoxymethane when employed in this reaction instead
of dimethoxymethane gave chloromethyl ethyl ether
was obtained (yield 78%).
1. Greene, T. W.; Wuts, P. G. M. Protective Groups in
Organic Synthesis; John Wiley & Sons: New York, 1999,
pp 17–59.
2
3
4
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972, 94, 7827–7832.
. Vila, A. J.; Cravero, R. M.; Gonzalez-Siera, M. Tetra-
hedron Lett. 1991, 32, 1929–1932.
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J. J. Am. Chem. Soc. 1987, 109, 5413–5419.
. (a) Yardley, J. P.; Fletcher, H. Synthesis 1976, 244;
1
Typical experimental procedure
(
2
b) Fuji, K.; Nakano, S.; Fujitha, E. Synthesis 1975, 276–
77; (c) Olah, G. A.; Hussain, A.; Gupta, B. G. B.;
CAUTION: The reaction should be carried out in an effi-
cient hood due to the acute toxicity and carcinogenicity
of the chloromethyl methyl ether. To ensure gas tight-
ness, PTFE-sleeves were used on all glass connections.
Benzoyl chloride 1 (9.686 g, 68.9 mmol), dimethoxy-
methane 2 (5.236 g, 68.9 mmol) and H PW O (1.50 g,
Narang, S. C. Sythesis 1981, 471–472; (d) Olah, G. A.;
Hussain, A.; Narang, S. C. Synthesis 1983, 896–897; (e)
Gras, J. L.; Chang, Y. K. W.; Guerin, A. Synthesis 1985,
74–75.
6. Weinstock, L. M.; Karady, S.; Roberts, F. E.; Hoinowski,
A. M.; Brenner, G. S.; Lee, T. B. K.; Lumma, W. C.;
Sletzinger, M. Tetrahedron Lett. 1975, 16, 3979–3982.
. Nebuo, N.; Masagi, O. Chem. Lett. 1987, 141–144.
. (a) Okuhara, T.; Mizuno, N.; Misono, M. Appl. Catal. A.
2001, 222, 63–77; (b) Misono, M. Chem. Commun. 2001,
3
12 40
0
.52 mmol) were taken in a 50 mL two necked round
7
8
bottomed flask. The mixture was stirred under N and
2
heated in an oil bath, thermostated at 60–65 °C for 4 h.
1
The reaction was conveniently monitored by H NMR.
1141–1153; (c) Kozhevnikov, I. V. Chem. Rev. 1998, 98,
171–198; (d) Kozhevnikov, I. V. Catal. Rev. 1995, 37, 311–
352; (e) Misono, M.; Nojiri, N. Appl. Catal. 1990, 64, 1–
The integrals of the product MOM-Cl signals (d = 3.52
and 5.46 ppm) were compared with those of di-
methoxymethane (d = 3.34 and 4.56 ppm). After cooling
to room temperature, the mixture was distilled at
30; (f) Kozhevnikov, I. V. Russ. Chem. Rev. 1993, 62, 473–
491.
1
30 °C. After discarding a small amount of the fore-
run, MOM-Cl (chloromethyl methyl ether) was collected
4.38 g, 79%). The purity, especially the absence of the
9. Izumi, Y.; Ono, M.; Kitagawa, M.; Yoshida, M.; Urabe,
K. Microporous Mater. 1995, 5, 255–262.
1
0. Marvel, C. S.; Porter, P. K. In Org. synth. Coll.; Wiley
Interscience, 1941; Vol. 1, pp 377–378.
(
bis(chloromethyl) ether in the crude or distilled product
was validated by H NMR spectroscopy (absence of a
CH signal at 5.56 ppm). The product contained only a
small amount of dimethoxymethane (0.1%). In the reac-
tion where diethoxymethane was employed as the acetal
1
11. (a) Jones, M. S. Synthesis 1984, 727; (b) Stadlwieser, J.
Synthesis 1985, 490.
2
1
2. Amato, J. S.; Karady, S.; Sletzinger, M.; Weinstock, L. M.
Synthesis 1979, 970.
1
3. Linderman, L. J.; Jaber, M.; Greidal, B. D. J. Org. Chem.
1994, 59, 6499–6500.
1
the product, chloromethyl ethyl ether showed H NMR
signals at d 5.5 (s, 2H), 3.8 (q, 2H), 1.3 (t, 3H).
14. Reggelin, M.; Sebastin, D. Synlett 2004, 1117.