SUBSTITUTION OF 9-(␣-BROMO-␣-ARYLMETHYLENE)FLUORENES
877
(0·1 ml, 1 mmol) was kept in a sealed ampoule for 70 h at
130 °C. After cooling, it was poured into ice–water (100 ml)
and the yellow precipitate formed was filtered and crystal-
persisted during the experiments, indicating the absence of
side reactions. The plots of the logarithms of the optical
density vs time became curved at higher (75%) reaction
percentages. Consequently, although the reactions were
followed for up to 4·5 half-lives, initial rate constants were
calculated and are given in the tables. Several kinetic runs
were repeated and reproducibility of the rate constants was
±1·5%.
lized
from
light
petroleum,
giving
9-(␣-p-
methoxyphenyl -␣ - trifluoroethoxymethylene) fluorene
as yellow crystals, m.p. 111–113 °C (85 mg, 75%). 1H NMR
(CDCl3), ␦: 3·94 (3H, s, OMe), 4·13 (2H, q, J=8·4 Hz,
CH2), 6·35 (1H, d, J=7·8 Hz, H-1), 6·91 (1H, t, J=7·3 Hz,
H-2), 7·10 (2H, d, J=7·6, An-H), 7·20 (1H, t, J=7·4 Hz, H-
3), 7·39 (2H, m), 7·44 (2H, d, J=7·6 Hz, An-H), 7·70 (1H,
m, H-8, 7·75–7·78 (1H, m), 8·29–8·34 (1H, m). Mass
spectrum (70 eV), m/z (relative abundance (%), assign-
ment): 382(96, M), 271 (100, MϪCO2CH2CF3). Analysis:
calculated for C23H17F3O2, C 72·27, H 4·48, F 14·91; found,
C 72·05, H 4.36, F 15·24%.
Reaction of 2. A solution containing
2 (0·1 g,
0·17 mmol) and Et3N (0·1 ml) in 70% MeCN–30% H2O
(8 ml) was kept in a sealed tube at 130 °C for 24 h. The
mixture was poured into water (100 ml), extracted with
CHCl3 (2ϫ10 ml) and the extract was washed with water
and dried (CaCl2). After evaporation of the solvent, TLC
showed three main spots. Chromatography on silica gave
fluorene (16 mg, 56%) and fluorenone (10 mg, 32%), which
Substitution of 1a with p-cresolate ion. To a solution of
p-TolONa (131 mg, 1 mmol) in DMSO (8 ml), 1a (181 mg,
0·5 mmol) was added and the mixture was heated at 80 °C
for 4 h, when TLC showed that all 1a had disappeared. The
mixture was poured into water (40 ml), filtered and the solid
obtained (60 mg, 32%) was crystallized from CH2Cl2,
giving 9-(␣-p-methoxyphenyl-␣-p-methylphenoxymethyle-
ne)fluorene as white crystals, m.p. 215 °C (48 mg, 25%). 1H
NMR (CDCl3), ␦: 2·23 (3H, s, Me), 3·83 (3H, s, MeO), 6·98
(8H, m, Ar-H), 7·22–7·27 (2H, m, Ar-H), 7·34 (1H, t,
J=7·3 Hz, Ar-H), 7·52 (2H, d, J=8·7 Hz, Ar-H), 7·76 (2H,
m, Ar-H), 8·17 (1H, d, J=7·8 Hz, H-8). Mass spectrum
(70 eV), m/z (relative abundance (%), assignment): 390 (65,
M), 283 (58, MϪOTol), 268 (22, MϪOTolϪMe), 133
(100, AnCO). Analysis: calculated for C28H22O2, C 86·13, H
5·68; found, C 86·25, H 5·75%.
1
were identified by comparison of their H NMR and IR
spectra with those of authentic samples.
ACKNOWLEDGEMENT
This work was supported by the United States – Israel
Binational Science Foundation (BSF), Jerusalem, to which
we are indebted.
REFERENCES
1. Part 59 of the series Nucleophilic Attacks on Carbon–Carbon
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Substitutions of compounds 1 with sodium p-toluene-
thiolate and methanethiolate. The following general
procedure was used for obtaining the substitution products.
To a solution of the bromide (0·7–1·0 g, 0·2–0·3 mmol) in
MeOH (5 ml) was added a solution of equimolar amount of
p-TolSNa in MeOH and the mixture was heated in a sealed
tube at 90 °C for 15–20 h. The precipitate formed after
cooling was filtered, washed with water (50 ml) and
crystallized from EtOH. The faster reaction with MeSNa
was performed at room temperature for 1f and at 40–50 °C
for 1d and 1e using 1·2–1·3 molar equivalents of MeSϪ .
After water–CHCl3 work-up, the solvent was evaporated
and the residue was crystallized from EtOH. Yields, melting
points and analytical and spectral data are given in Tables 3
and 4.
Kinetics. A 1·8 ml volume of a 2·10Ϫ4
and 1·2 ml of a 0·01 solution of MeSNa or a 0·004
M
solution of 1
M
M
7. Z. Rappoport and A. Gal, J. Org. Chem. 37, 1174 (1972).
8. We are indebted to Dr G. Lodder, University of Leiden for
these compounds.
9. B. A. Shainyan, I. Eventova and Z. Rappoport, J. Chem. Soc.,
Perkin Trans. 1 1287 (1993).
solution of p-TolSNa, both in 80% MeCN, were mixed in a
thermostated 1 cm UV cell and the reaction was followed
spectrophotometrically in the range 300–380 nm. Constant
isosbestic points (max =319, 328, 327, 325, 326 and 328 nm
for X=NO2, CN, Br, H, Me and MeO, respectively)
10. (a) T. W. Bentley and G. Llewellyn, Prog. Phys. Org. Chem.
© 1997 John Wiley & Sons, Ltd.
JOURNAL OF PHYSICAL ORGANIC CHEMISTRY, VOL. 10, 871–878 (1997)