J. CHEM. RESEARCH (S), 1997 169
1
Table 1 H NMR spectra of fluorenophanes [d values (CDCl
3
)]
Dithiafluorenophanes 3. General Procedure: Preparation of
6
,15,18-tri-tert-butyl-2,11-dithia[3]metacyclo[3](1,8)fluorenophane
t
3
Compound
Bu
R
9-H
3a.sA solution of 1 (1.09 g, 2.9 mmol) and 2a (0.70 g, 3.1 mmol)
in EtOH–benzene (1:1; 300 ml) was added dropwise from a Hersh-
berg funnel with stirring to a solution of CsOH (1.21 g, 8.07 mmol)
1
1.41 (18 H)
1.33 (9 H)
3.95 (s)
and NaBH
had been evaporated, the residue was extracted with CH
extract was washed with water, dried over MgSO , and evaporated
in vacuo to give 3a (1.22 g, 79%) as colourless prisms, mp
34–235 °C (from hexane) (Found: C, 79.32; H, 8.41. C35
4
(0.12 g, 3.2 mmol) in EtOH (2 l) for 1 h. After solvents
3
3
3
4
a
b
c
7.09
2.69 (br s)
2
Cl . The
2
1
.37 (18 H)
1.32 (9 H)
.36 (18 H)
1.32 (9 H)
.36 (18 H)
(Ar-H)
4
2.39
(CH )
3
1.89 (d, J 22 Hz)
2.90 (d, J 22 Hz)
1
2
H
44 2
S
ǹ
requires C, 79.47; H, 8.40%); m/z 528 (M ); d
18 H, s), 2.70 (2 H, br s), 3.70 (4 H, s), 3.74 (4 H, s), 7.17 (2 H, d,
J 1.5 Hz), 7.19 (2 H, s), 7.45 (1 H, s), 7.62 (2 H, d, J 1.5 Hz).
,15,18-Tri-tert-butyl-2,11-dithia[3]metacyclo[3](1,8)fluoreno-
phane 3b.s3b was obtained according to the general procedure.
H
1.34 (9 H, s), 1.38
3.86
(OCH
2.03 (d, J 22 Hz)
3.20 (d, J 22 Hz)
(
1
3
)
a
0.69 (9 H)
7.09
(Ar-H)
3.07 (d, J 19 Hz)
3.80 (d, J 19 Hz)
6
1.37 (18 H)
3
4
Thus 1 (0.53 g, 1.41 mmol) and 2b (0.35 g, 1.46 mmol) gave 3b
(
0.64 g, 84%) as colourless prisms, mp 189–191 °C (from hexane)
S
But
(Found: C, 79.83; H, 8.49. C H S requires C, 79.63; H, 8.56%);
36 46
2
H
ǹ
But
m/z 542 (M ); d
H
1.32 (9 H, s), 1.36 (18 H, s), 1.90 (1 H, d, J 22 Hz),
2
.39 (3 H, s), 2.90 (1 H, d, J 22 Hz), 3.48 (2 H, d, J 12 Hz), 3.74 (2 H,
d, J 14 Hz), 3.95 (2 H, d, J 14 Hz), 3.99 (2 H, d, J 12 Hz), 7.14 (2 H,
s), 7.15 (2 H, d, J 1.5 Hz), 7.61 (2 H, d, J 1.5 Hz).
S
But
6
,15,18-Tri-tert-butyl-9-methoxy-2,11-dithia[3]metacyclo[3]-
(
1,8)fluorenophane 3c.s3c was obtained according to the general
3a
3
4
procedure. Thus 1 (0.32 g, 0.85 mmol) and 2c (0.23 g, 0.90 mmol)
gave 3c (0.34 g, 72%) as colourless prisms, mp 191–193 °C (from
hexane) (Found: C, 77.58; H, 8.50. C36
.31%); m/z 558 (M ); d
H
46
S
2
O requires C, 77.35; H,
1.32 (9 H, s), 1.35 (18 H, s), 2.03 (1 H, d,
ǹ
But
8
H
But
H
J 22 Hz), 3.21 (1 H, d, J 22 Hz), 3.51 (2 H, d, J 12 Hz), 3.60 (2 H, d,
J 14 Hz), 3.86 (3 H, s), 3.93 (2 H, d, J 14 Hz), 3.99 (2 H, d, J 12 Hz),
7
.13 (2 H, d, J 1.5 Hz), 7.18 (2 H, s), 7.58 (2 H, d, J 1.5 Hz).
5
,13,16-Tri-tert-butyl[2]metacyclo[2](1,8)fluorenophane 4a.—The
δ 5.84
But
sulfone derivative of 3a (0.52 g, 0.88 mmol) was pyrolysed at 500 °C
under reduced pressure (2 Torr) in a horizontal quartz tube. The
resultant product was chromatographed with hexane as an eluent
to afford 4a (0.12 g, 29%) from the first fraction as colourless
4a
Scheme 2
needles, mp 296–298 °C (from hexane) (Found: C, 90.16; H, 9.66.
ǹ
C
1
35
H
44 requires C, 90.44; H, 9.54%); m/z 464 (M ); d
H
0.69 (9 H, s),
the tert-butyl group. Inversion of one aromatic ring occurs
.37 (18 H, s), 2.93–3.86 (8 H, m), 3.07 (1 H, d, J 19 Hz), 3.80 (1 H,
d, J 19 Hz), 5.83 (2 H, s), 6.91 (2 H, d, J 1.5 Hz), 7.09 (1 H, s), 7.23
(2 H, d, J 1.5 Hz).
during the transformation into a smaller cyclic system
(
Scheme 2).
Further investigations of other types of 1,8-bridged fluor-
enophanes are in progress.
Received, 5th August 1996; Accepted, 21st January 1997
Paper E/6/05440D
Experimental
1
All melting points are uncorrected. H NMR spectra were
recorded at 500 MHz on a Nippon Denshi JEOL a-500 spectro-
meter in CDCl
3
with Me Si as an internal reference. Mass spectra
4
References
were obtained on a Nippon Denshi JEOL DX-300 spectrometer at
7
5 eV using a direct-inlet system. Elemental analyses were carried
1 F. V o¨ gtle, Supramolecular Chemistry, Wiley, Chichester, 1989; F.
Diederich, Cyclophanes, The Royal Society of Chemistry, Cam-
bridge, 1991; F. V o¨ gtle, Cyclophane Chemistry, Wiley, Chichester,
1989.
out on a Yanaco MT-3 spectrometer. Column chromatography was
performed on silica gel (Wako gel, C-300).
(
3-tert-Butyl-5-sulfanylmethylphenyl)methanethiol 2a.sA solu-
tion of 1,3-bis(bromomethyl)-5-tert-butylbenzene (30 g, 93 mmol)
and thiourea (18.0 g, 0.24 mol) in DMSO (450 ml) was stirred at
room tempearture for 15 h under an argon stream. After the reac-
tion mixture had been poured into cold 10% aqueous NaOH (500
ml) and acidified with 10% hydrochloric acid, it was extracted with
2 M. W. Haenel, Tetrahedron Lett., 1976, 3121; 1977, 1273.
3 A. Tsuge, T. Yamasaki, T. Moriguchi, T. Matsuda, Y. Nagano, H.
Nago, S. Mataka, S. Kajigaeshi and M. Tashiro, Synthesis, 1993,
205.
4 M. Tashiro and T. Yamato, J. Org. Chem., 1981, 46, 1543.
5 A. Tsuge, T. Sawada, S. Mataka, N. Nishiyama, H. Sakashita and
M. Tashiro, J. Chem. Soc., Chem. Commun., 1990, 1066; A. Tsuge,
T. Sawada, S. Mataka, N. Nishiyama, H. Sakashita and M. Tashiro,
J. Chem. Soc., Perkin Trans 1, 1992, 1489; A. Tsuge, H. Takeo, H.
Kabashima, T. Moriguchi, S. Mataka and M. Tashiro, Chem. Lett.,
1996, 425.
CH
2
Cl
2
. The extract was washed with water, dried over MgSO , and
4
evaporated in vacuo to leave a residue which was distilled to afford
the bis(thiol) 2a (16.5 g, 79%) as a colourless liquid, bp 140–145 °C
at 2 Torr (Found: C, 63.86; H, 8.13. C12
H
18
S
2
requires C, 63.65; H,
1.31 (9 H, s), 1.75 (2 H, t, J 8 Hz), 3.70
4 H, d, J 8 Hz), 7.12 (1 H, s), 7.19 (2 H, s).
ǹ
8
.03%); m/z 226 (M ); d
H
(