Russian Journal of Applied Chemistry, 2009, Vol. 82, No. 8, pp. 1431−1434.
Pleiades Publishing, Ltd., 2009.
Original Russian Text
I.N. Bardasov, O.V. Kayukova, Ya.S. Kayukov, O.V. Ershov, O.E. Nasakin, 2009, published in Zhurnal Prikladnoi Khimii, 2009,
Vol. 82, No. 8, pp. 1332−1334.
AND INDUSTRIAL ORGANIC CHEMISTRY
New Procedures for Preparing 2,2,3,3-Tetracyanocyclopropyl
I. N. Bardasov, O. V. Kayukova, Ya. S. Kayukov, O. V. Ershov, and O. E. Nasakin
Ilya Ulyanov Chuvash State University, Cheboksary, Chuvashia, Russia
Received November 18, 2008
Abstract—New procedures were developed for preparing 2,2,3,3-tetracyanocyclopropyl ketones, based on
reactions of substituted glyoxals with bromomalononitrile.
Tetracyanocyclopropyl ketones are highly reactive and
can be used in syntheses of various framework and fused
heterocyclic systems [1, 2]. However, the known procedures
for their preparation are labor-consuming and involve the
use of expensive chemicals such as tetracyanoethylene
, which largely restricts studies of their properties.
It is known that alkyltetracyanocyclopropanes can be
prepared by the Wideqvist reaction consisting in treatment
of carbonyl compounds with bromomalononitrile and
KI in aqueous ethanol at room temperature for 0.5–12 h
[3–6]. Application of this procedure to synthesis of
cyclopropanes substituted with ﬁ ve and six electron-
withdrawing groups is inefﬁ cient, because, as noted
previously, such cyclopropanes actively react with iodides
to form propenides . Indeed, by the Wideqvist reaction
with substituted glyoxals as carbonyl compounds, the
expected 2,2,3,3-tetracyanocyclopropyl ketones Ia–Ic
were prepared in low yields (21–26%) and only with a
few aryl substituents (Scheme 1).
Therefore, our goal was to find procedures for
preparing compounds I without using iodides as
reductants. As we showed previously , in some
cases cyclopropanation of carbonyl compounds with
bromomalononitrile can occur without participation of
KI . Using this approach, by treatment of substituted
glyoxals with excess bromomalononitrile in isopropyl
alcohol, we prepared cyclopropanes Ia–If in 37–57%
yield based on glyoxal. The drawback of this procedure
is that bromomalononitrile should be taken in a threefold
excess (Scheme 2).
It is known that bromomalononitrile is capable
Ar = Ph (a), 4-BrPh (b), or 4-MeOPh (c).