214 Ba´lint et al.
TABLE 3 31P NMR Chemical Shifts for 1-Alkoxy-3-phospholene-1-oxides 6a–e and 8a–e
6a
6b
6c
6d
6e
8a
8b
8c
8d
8e
δmP easured (CDCl3)
74.7
74.5
73.2
74.7
76.0
68.3
68.5
66.8
68.6
69.9
δlPiterature
67.0
[9]
–
[6]
–
[6]
74.6
[8]
76.1
[10]
68.4
[11]
68.5
[8]
–
[7]
68.4
[8]
70.7
[12]
Reference
EXPERIMENTAL
General
Evaporation of the volatile components provided the
crude product that was passed through a thin (ca.
3 cm) layer of silica gel using 3% MeOH in CH2Cl2
as the eluant to give an oil analyzed by GC-MS
or GC.
The alkylations were carried out in a CEM Discover
microwave reactor equipped with a pressure con-
troller using 30–40 W irradiation.
As a comparison, similar reactions were carried
out with conventional heating. The work-up was
similar to that described above for the microwave
reactions.
GC was carried out on an HP5890 series 2 GC-
FID chromatograph, using a 15 m × 0.18 mm Restek,
Rtx-5 column with a film layer of 0.20 μm. The tem-
perature of the column was initially held at 40◦C for
1 min, followed by programming at 25◦C/min up to
300◦C, and a final period at 300◦C (isothermal) for
10 min. The temperature of the injector was 290◦C,
and of the FID detector was 300◦C. The carrier gas
was H2.
GC-MS was carried out on an Agilent 6890 N-
GC-5973 N-MSD chromatograph, using a 30 m ×
0.25 mm Restek, Rtx-5SILMS column with a film
layer of 0.25 μm. The initial temperature of column
was 45◦C for 1 min, followed by programming at
10◦C/min up to 310◦C and a final period at 310◦C
(isothermal) for 17 min. The temperature of the in-
jector was 250◦C. The carrier gas was He, and the
operation mode was splitless.
31P NMR characterization of cyclic phosphinic
esters 6 and 8 can be found in Table 3.
ACKNOWLEDGMENT
G. K. is grateful to Professor Dr. Harry R. Hudson
(London Metropolitan University) for his advice.
REFERENCES
[1] Crofts, P. C. In Organic Phosphorus Compounds;
Kosolapoff, G. M.; Maier, L. (Eds.); Wiley: New York,
1973; Vol. 6, Ch. 14, SubCh. XXIe, p. 39.
[2] Edmundson, R. S. In Comprehensive Organic Chem-
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(Vol. Ed.); Pergamon: Oxford, UK, 1979; Vol. 2, Ch.
10.5.5, p. 1291.
General Procedure for Solid–Liquid Phase
Esterification of 3-Hydroxy-3-phospholene-oxide
Derivatives under Solventless and MW
Conditions
[3] Quin, L. D. In The Heterocyclic Chemistry of Phos-
phorus: System Based on the Phosphorus–Carbon
Bond; Wiley: New York, 1981.
[4] Keglevich, G.; Petneha´zy, I.; Miklo´s, P.; Alma´sy, A.;
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3983.
A mixture of 0.76 mmol of 3-hydroxy-3-phospholene
oxide (0.10 g of 1-hydroxy-3-methyl-3-phospholene
oxide 5 or 0.11 g of 1-hydroxy-3,4-dimethyl-3-
phospholene oxide 7), 0.10 g (0.76 mmol) of K2CO3,
0.91 mmol of alkyl halide (0.10 mL of ethyl io-
dide, 0.08 mL of 1-bromopropane, 0.09 mL of
2-bromopropane, 0.10 mL of 1-bromobutane, or
0.11 mL benzyl bromide), and where it was applied,
10 mg (0.038 mmol) of TEBAC in a closed vial was
irradiated in a CEM Discover (300 W) microwave
reactor at 10–20 W for the appropriate time. (The
pressure developed was in the range of 2–3 bar.)
The reaction mixture was taken up in 50 mL
of ethyl acetate, and the suspension was filtered.
[5] Hunger, K.; Hasserodt, U.; Korte, F. Tetrahedron
1964, 20, 1953.
[6] Keglevich, G.; Brlik, J.; Janke, F.; T˝oke, L. Het-
eroatom Chem 1990, 1, 419.
´
[7] Keglevich, G.; T˝oke, L.; Kova´cs, A.; To´th, G.; Ujsza´szy,
K. Heteroatom Chem 1993, 4, 61.
[8] Kiss, N. Zs.; Luda´nyi, K.; Drahos, L.; Keglevich, G.
Synth Commun 2009, 39, 2392.
[9] Blackburn, G. M.; Cohen, J. S.; Weatherall, I. Tetra-
hedron 1971, 27, 2903.
[10] Bujard, M.; Gouverneur, V.; Mioskowski, C. J Org
Chem 1999, 64, 2119.
[11] Hammond, P. J.; Scott, G.; Hall, C. D. J Chem Soc,
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[12] Briot, A.; Bujard, M.; Gouverneur, V.; Nolan, S. P.,
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Heteroatom Chemistry DOI 10.1002/hc