Russian Chemical Bulletin, International Edition, Vol. 53, No. 8, pp. 1755—1760, August, 2004
1755
Oxidative transformation of 1,3ꢀdioxacycloalkanes
induced by chlorine dioxide
a
b
b
a†
A. R. Abdrakhmanova,a N. N. Kabal´nova, L. Z. Rol´nik, G. G. Yagafarova, and V. V. Shereshovets
ꢀ
аInstitute of Organic Chemistry, Ufa Research Center of the Russian Academy of Sciences,
71 prosp. Oktyabrya, 450054 Ufa, Russian Federation.
Fax: +7 (347 2) 35 6066. Eꢀmail: chemox@anrb.ru
bUfa State Petroleum Technical University,
1 ul. Kosmonavtov, 450062 Ufa, Russian Federation.
Fax: +7 (347 2) 42 0932
The products and kinetic regularities of the reactions of 1,3ꢀdioxacycloalkanes with chloꢀ
rine dioxide were studied. The effects of the nature of solvent and the temperature on the
reaction rate were considered and the activation parameters were determined.
Key words: chlorine dioxide, 1,3ꢀdioxacycloalkanes, kinetics, products.
ClO2 (1.24—6.0 mmol) in a known concentration was added.
The reaction was carried out for 4—7 h. The solvent was evapoꢀ
rated and the reaction products were identified.
The products of oxidative transformations of 1,3ꢀdiꢀ
oxacycloalkanes and their derivatives find extensive pracꢀ
tical application.1,2 Chlorine dioxide is of obvious interest
as an oxidant. Meanwhile, data on reactions of chlorine
dioxide in nonaqueous media are virtually missing.
In this work, we studied the products and the kinetic
regularities of the reaction of chlorine dioxide with 1,3ꢀdiꢀ
oxacycloalkanes (DH) of various structures: 2ꢀisopropylꢀ
1,3ꢀdioxolane (1), 2ꢀphenylꢀ1,3ꢀdioxolane (2), 2,2ꢀpentaꢀ
methyleneꢀ1,3ꢀdioxolane (3), 4ꢀchloromethylꢀ1,3ꢀdiꢀ
oxolane (4), 4ꢀchloromethylꢀ2ꢀphenylꢀ1,3ꢀdioxolane (5),
4ꢀmethylꢀ1,3ꢀdioxane (6), 2ꢀisopropylꢀ4ꢀmethylꢀ1,3ꢀdiꢀ
oxane (7), 4ꢀmethylꢀ2ꢀphenylꢀ1,3ꢀdioxane (8), and
5,5ꢀdimethylꢀ2ꢀphenylꢀ1,3ꢀdioxane (9).
Oxidation of 1,3ꢀdioxanes with chlorine dioxide in the presꢀ
ence of 2,2,5,5ꢀtetramethylꢀ4ꢀphenylꢀ3ꢀimidazolinꢀ1ꢀoxyl
3ꢀoxide (general procedure). A specified amount of 1,3ꢀdioxane
(0.86—4.0 mmol) in MeCN (3 mL) was placed in a reactor, the
iminoxyl radical (>N—O•) and KBr were added, and then
the specified amount of a solution of ClO2 with a known conꢀ
centration was introduced. The reaction was carried out for 4 h
at 35 °C. Acetonitrile was evaporated and the reaction products
were identified. The ratio [DH] : [>N—O•] : [KBr] : [ClO2] =
1 : 0.01 : 1 : 2.
The kinetics of oxidation of 1,3ꢀdioxacycloalkanes with chloꢀ
rine dioxide was studied by monitoring the consumption of ClO2.
The change in chlorine dioxide concentration was determined
by spectrophotometry (Specord M40, Carl Zeiss Jena) by moniꢀ
toring the decrease in the optical density at λmax in thermostated
quartz cells (the optical lengths were 1 and 0.1 cm, the error was
≤5%). The concentration of 1,3ꢀdioxacycloalkanes and ClO2
Experimental
Chlorine dioxide was prepared by the reaction of potassium
chlorate with oxalic acid in the presence of sulfuric acid accordꢀ
ing to a known procedure.3 The concentration of ClO2 was
determined by spectrophotometry on a Specord M40 instruꢀ
was varied in the ranges of 0.04—3.2 and (4—8)•10–3 mol L–1
,
respectively. Benzene, acetone, MeCN, CCl4, AcOEt, EtOH,
and MeOH were used as solvents. The temperature was varied in
the range of 30.6—61 °C.
ment at λ
= 360 nm. Solvents were purified by standard
max
procedures.4
The starting 1,3ꢀdioxacycloalkanes and the reaction prodꢀ
ucts were analyzed by GLC using a Chrom 5 chromatograph
(3.5 m × 3 mm column, 5% SEꢀ30 on Chromaton) and by 1H
and 13C NMR spectroscopy on a Bruker AMꢀ300 instrument
(300 MHz). The solvents used were CDCl3 (99.8 at.% D;
Aldrich) and acetoneꢀd6 (99.9 at.% D; Aldrich).
Oxidation of 1,3ꢀdioxacycloalkanes with chlorine dioxide (genꢀ
eral procedure). 1,3ꢀDioxacycloalkane (0.86—4.0 mmol) in 3 mL
of MeCN was maintained at 35 °C and a specified amount of
Results and Discussion
Reaction products. The oxidation of compounds 1, 2,
and 4—9 with chlorine dioxide gives the corresponding
glycol monoesters, their yield reaching 60% (Scheme 1,
Tables 1, 2). The oxidation of nonsymmetrical 1,3ꢀdiꢀ
oxacycloalkanes 4, 5, 7, and 8 affords a mixture of two
isomeric esters of types A and B in 2 : 1 ratio. The reaction
of 1,3ꢀdioxolane 3 with ClO2 results in cyclohexanone
(82%) and the product of its chlorination, chlorocycloꢀ
† Deceased.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1688—1692, August, 2004.
1066ꢀ5285/04/5308ꢀ1755 © 2004 Springer Science+Business Media, Inc.