organic compounds
Acta Crystallographica Section C
Crystal Structure
Communications
groups on the course of the desulfurization reaction. Detailed
studies of 1,3-thiazolidine derivatives show that the regio-
selectivity of the [3+2]-cycloaddition leading to the formation
of the ®ve-membered heterocyclic ring is dependent on the
type of thioketone used (Domagaøa, Linden et al., 2003).
ISSN 0108-2701
Dimethyl 3,4,5,5-tetraphenyl-1,3-
thiazolidine-2,2-dicarboxylate and
3,3-dichloro-2,2,4,4,30-pentamethyl-
r-20,t-40-diphenylcyclobutane-1-spiro-
50-1,3-thiazolidine
Maøgorzata Domagaøa,a* Marcin Palusiak,a Arno
Pfitzner,b Manfred Zabel,b Katarzyna Urbaniak,c
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Grzegorz Mloston and Søawomir J. Grabowski
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Department of Crystallography and Crystal Chemistry, University of èodz, Pomorska
149/153, 90236 èodz, Poland, bInstitut fur Anorganische Chemie, Universitat
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Regensburg, 93040 Regensburg, Germany, and cSection of Heteroorganic
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Compounds, University of èodz, Narutowicza 68, 90136 èodz, Poland
Correspondence e-mail: reczek@uni.lodz.pl
Received 27 May 2004
Accepted 21 June 2004
Online 21 July 2004
The ®rst of the title compounds, C31H27NO4S, (V), crystallizes
in the monoclinic space group P21/c with two independent
molecules in the asymmetric unit, while the second,
C23H27Cl2NS, (IX), crystallizes in the orthorhombic space
group Pbca with one molecule in the asymmetric unit. In both
crystal structures, the 1,3-thiazolidine ring adopts a half-chair
conformation. The crystal structures are stabilized by weak
CÐHÁ Á ÁO and CÐHÁ Á ÁCl hydrogen bonds in (V) and (IX),
respectively.
Another aim of the present work was an analysis of the
hydrogen bonding, one of the most important interactions
in¯uencing the arrangement of molecules in molecular organic
crystals (Desiraju, 1989; Jeffrey & Saenger, 1994; Desiraju &
Steiner, 1999). Studies of hydrogen-bond interactions have
shown that the H-atom-donating and -accepting abilities of
molecules determine the architecture of crystals. In recent
years, the role of CÐHÁ Á ÁX hydrogen bonds in crystal engi-
neering has been extensively studied. Among CÐHÁ Á ÁX
interactions, the CÐHÁ Á ÁO type is most often investigated
because it occurs most frequently in crystals. For the crystal
structures reported here, not only CÐHÁ Á ÁO interactions
occur but also CÐHÁ Á ÁS and CÐHÁ Á ÁN ones, which are not
well known because of their rare occurrence in crystals (Taylor
& Kennard, 1982; Desiraju, 1995; Desiraju & Steiner, 1999).
The contacts mentioned above have been investigated
previously, both theoretically and experimentally (Domagaøa,
Grabowski et al., 2003, 2004). CÐHÁ Á Áꢀ contacts are another
type of interaction investigated here for the crystal structures
of (V) and (IX). Such interactions often have an in¯uence on
the crystal packing (Ciunik et al., 1998; Ciunik & Jarosz, 1998).
The asymmetric unit of compound (V) contains two inde-
pendent molecules (denoted A and B), which have the same
®ve-membered heterocyclic ring conformation and selected to
have opposite absolute con®gurations. The chiral centre is at
atom C4. In Fig. 1, the phenyl substituent is attached in the S
con®guration in molecule A, whereas in molecule B this
con®guration is R. Compound (IX) (Fig. 2) crystallizes with
one molecule in the asymmetric unit. There are two centres of
opposite chirality in this molecule, at atoms C2 and C4.
Comment
1,3-Thiazolidines are known to exhibit biological activity
(Hwu et al., 1999; Pellegrini et al., 1999) and have also been
explored as valuable starting materials for the preparation of
more complex structures (Bringmann et al., 2000; Jin & Kim,
2002). The title compounds, (V) and (IX), were obtained
by the [3+2]-dipolar cycloaddition of an azomethine ylide,
generated in situ by thermal ring-opening of the appropriate
aziridine in the presence of thiobenzophenone, (IV), or 3,3-
dichloro-2,2,4,4-tetramethylcyclobutanethione, (VIII) (see
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scheme), according to the general protocol of Mloston &
Skrzypek (1990).
Sometimes, desulfurization of 1,3-thiazolidines with Raney
nickel results unexpectedly in ring contraction and the
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formation of the corresponding azetidine derivative (Mloston,
Urbaniak & Heimgartner, 2002; Mloston, Urbaniak et al.,
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2002; Urbaniak et al., 2004). For this reason, our studies of this
group of compounds concern not only the elucidation of their
structures, conformations and con®gurations, but also the
determination of the in¯uence of the location of the ester
Acta Cryst. (2004). C60, o595±o599
DOI: 10.1107/S0108270104015045
# 2004 International Union of Crystallography o595