Chemistry of Heterocyclic Compounds, Vol. 42, No. 11, 2006
LETTERS TO THE EDITOR
2,5,2',5'-TETRAHYDRO[3,3']BIFURANYL.
A NOVEL HETEROCYCLIC SYSTEM FROM
2-BUTENE-1,4-DIOL
E. V. Pyatnitsyna, M. M. El'chaninov, and B. S. Lukyanov
Keywords: copper acetate, 2-butene-1,4-diol, 2,5-dihydrofuran, dimerization, cyclodehydration.
Hydrogenation of 2-butyne-1,4-diol to 2-butene-1,4-diol (1) on suspended palladium catalysts at
atmospheric pressure is accompanied by the formation of side products (n-butanol, γ-hydroxybutyraldehyde, and
others [1]) but the main loss of target compound is seen at the stages of distillation of water and the vacuum
fractionation of the hydrogenation catalyzate as a result of polymerization of compound 1. With the aim of
stabilizing the 2-butene-1,4-diol copper acetate monohydrate was added to the reaction product. Upon
distillation the overhead fractions unexpectedly showed the presence of a novel side product which was
separated and identified as 2,5,2'5'-tetrahydro[3,3']bifuranyl (3). A possible mechanism for its formation includes
a stage of cyclodehydration of diol 1 and a Glaser type oxidative dimerization of the 2,5-dihydrofuran (2).
.
Cu(OAc)2 H2O
–H2O
CH2–CH=CH–CH2
OH OH
O
O
O
3
2
1
The structure of the novel heterocyclic system 3 was confirmed by physicochemical methods and by a
counter synthesis.
1
IR spectra were taken on a Specord IR-75 instrument using vaseline oil. The H NMR spectra were
obtained on a Varian Unity-300 (300 MHz) machine using CDCl3 relative to the residual solvent signal at 7.26
ppm. Mass spectra were taken on a Varian MAT-3 instrument using EI (70 eV).
2,5-Dihydrofuran (2). The catalyst (2% Pd/C, 0.1 g) was added with stirring to 2-butene-1,4-diol
(1, 39.8 g, 0.45 mol). The mixture was heated above 100oC and the 2,5-dihydrofuran raw material was distilled
off until less that about 5 ml of liquid remained in the flask. The raw material was then distilled and the fraction
with bp 53-56oC was collected to give the 2,5-dihydrofuran (21.4 g, 66%). The product was identical to that
prepared by the catalytic dehydration of 2-butene-1,4-diol 1 in [3].
2,5,2',5'-Tetrahydro[3,3']bifuranyl (3). A. The overhead fraction in the distillation of compound 1
(50 ml) was held in a cold compartment for about 6 days. The precipitate formed was separated, washed with
__________________________________________________________________________________________
Southern Russia State Technical University. Novocherkassk 346428, e-mail: koch@org.novoch.ru. a Institute
of Physical and Organic Chemistry, Rostov State University, Rostov-on-Don 344090, Russia,
e-mail: bluk@ipoc.rus.ru. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1724-1725,
November, 2006. Original article submitted July 15, 2006.
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0009-3122/06/4209-1366©2006 Springer Science+Business Media, Inc.