organic compounds
The crystal structure of (II) is stabilized by both intra- and
intermolecular classical and weak hydrogen bonding (Table 2;
for simplicity the very extensive intramolecular hydrogen
bonding has been omitted from this table but can be found in
the CIF). The dominant intermolecular interaction in the
structure is an NÐHÁ Á ÁO hydrogen bond between a pair of
dimer that can be described by the R22(8) graph set (Fig. 2a).
For the alternative orientation (Orient-B), the NÐHÁ Á ÁO
hydrogen bonding (between N1A and O2ii in this case) results
in a hydrogen-bonded dimer that can be described by the
R22(14) graph set (Fig. 2b). Interestingly, the hydrogen-bond
dimer formed by a pair of Orient-A molecules has a DÁ Á ÁA
Ê
molecules forming
a
hydrogen-bonded dimer. The
distance of 3.038 (16) versus 3.31 (3) A in the dimer formed by
morphology of this hydrogen-bonded network differs signi®-
cantly between the two molecular orientations, though the
overall appearance is very similar (Fig. 2). For Orient-A, the
NÐHÁ Á ÁO hydrogen bonding (between N1 and O2ii;
symmetry code as in Table 2) results in a hydrogen-bonded
a pair of Orient-B molecules. The shorter DÁ Á ÁA distance
between Orient-A molecules implies that this orientation is
more stable and this assumption is corroborated by the higher
frequency of Orient-A (63% occurrence). Nevertheless, the
frequency of the Orient-B orientation is still very high. Rather
than the extremes of Orient-A- and Orient-B-only dimers, it is
likely that the `real' average situation in a crystal is a
hydrogen-bonded relationship in which Orient-A is about
26% (frequency of Orient-A minus frequency of Orient-B) of
the time hydrogen bonded to other Orient-A molecules and
the rest of the time hydrogen bonded to Orient-B molecules
(37% of the time minus the frequency of Orient-B). This
(Orient-A + Orient-B) arrangement would probably not be as
energetically unfavourable as Orient-B-only hydrogen-
bonded dimers, being made up of one hydrogen bond of each
Ê
Ê
type of orientation, i.e. one 3.0 A and one 3.3 A inter-
molecular NÐHÁ Á ÁO bond. These hydrogen-bonded dimers
are further stabilized by CÐHÁ Á Áꢀ [C18ÐH18Á Á ÁCg(C1±C6)ii]
and CÐHÁ Á ÁO (C2ÐH2Á Á ÁO2) interactions (Fig. 2). The
stabilization due to these extra weak interactions is probably
also a signi®cant contributor to the stability of the Orient-B
dimers as it would probably make the conversion of (Orient-
B + Orient-B) (if they exist) and (Orient-B + Orient-A)
dimers to Orient-A-only dimers quite dif®cult.
Finally, all the hydrogen-bonded dimers interact further
with neighbouring dimers through CÐHÁ Á ÁO interactions
(C16ÐH16Á Á ÁO1 and C20ÐH20CÁ Á ÁO1) to form layers
perpendicular to the (100) direction.
Experimental
p-Toluenesulfonyl chloride (11.80 g, 62 mmol) was added to 2-amino-
phenol (2.25 g, 21 mmol) dissolved in pyridine (50 ml) and stirred
under N2 for 60 h. The pyridine was evaporated and CH2Cl2 (100 ml)
was added to the resulting residue. The organic phase was then
washed with HCl (0.5 M, 2 Â 50 ml), water (50 ml) and brine (50 ml),
after which it was dried (MgSO4) and evaporated under reduced
pressure to afford compound (II) as a yellow solid. This solid was
recrystallized from hot EtOH to give white crystals of (II) (6.43 g,
87%, m.p. 410±412 K). NMR: ꢁH (300 MHz, CDCl3) 7.69 (d, 2H, J =
8.3 Hz, 2 Â ArÐH), 7.64 (d, 2H, J = 8.3 Hz, 2 Â ArÐH), 7.55 (dd, 1H,
J = 8.1 and 1.3 Hz, ArÐH), 7.35 (d, 2H, J = 8.3 Hz, 2 Â ArÐH), 7.19
(d, 2H, J = 8.3 Hz, 2 Â ArÐH), 7.20±7.15 (m partially under d, 1H,
ArÐH), 7.08 (br s, 1H, NH), 6.98 (dt, 1H, J = 1.3 and 8.0 Hz, ArÐH),
6.81 (dd, 1H, J = 8.3 and 1.3 Hz, ArÐH), 2.48 (s, 3H, ArÐCH3), 2.36
(s, 3H, ArÐCH3); ꢁC (75 MHz, CDCl3) 146.4 (ArÐO), 144.0 (ArÐ
N), 140.2 (ArÐS), 136.2 (ArÐS), 131.4 (ArÐC), 130.1 (ArÐCH),
130.0 (ArÐC), 129.6 (ArÐCH), 128.4 (ArÐCH), 127.9 (ArÐCH),
127.3 (ArÐCH), 125.5 (ArÐCH), 123.3 (ArÐCH), 123.0 (ArÐCH),
21.8 (ArÐCH3), 21.5 (ArÐCH3); ꢂmax (thin ®lm, NaCl plate, cm 1):
3361, 3020, 1599, 1495, 1340, 1293, 1215.
Figure 2
Hydrogen-bonded dimers in the structure of (II). These diagrams
represent the extremes in which (a) Orient-A molecules hydrogen bond
to other Orient-A molecules and (b) Orient-B molecules hydrogen bond
to other Orient-B molecules. The most frequent real situation is probably
a combination of the two. Indicated on the diagrams are the NÐHÁ Á ÁO
(N1AÐH1AÁ Á ÁO2), CÐHÁ Á ÁO (C2ÐH2Á Á ÁO2) and CÐHÁ Á Áꢀ inter-
actions for both types of hydrogen-bonded dimer. Molecules (i) and (ii)
are at the symmetry positions (x, y, z) and ( x + 2, y, z + 1),
respectively.
ꢁ
o310 Morgans et al. C20H19NO5S2
Acta Cryst. (2007). C63, o309±o311
Morgans
