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Y.V. Zonov et al. / Journal of Fluorine Chemistry 128 (2007) 1058–1064
ether. The extract was dried over MgSO . The solvent was
4
3.5.3. Perfluoro-1,1-diethylbenzocyclobutene (20)
To a solution of CF COOH (1 g, 8.77 mmol) in SbF (4.1 g,
18.91 mmol) mixture (5.65 g, 12.61 mmol) containing com-
distilled off and the residue was sublimed (90 8C, 5 Torr)
to give 0.81 g of mixture, which contained ( F NMR)
compounds 12 and 13 in the ratio 36:64 (yield 35% and
3
5
1
9
pound 20 and perfluoro-1,2-diethylbenzocyclobutene (46) in
1
9
62%, respectively).
. Analogously to procedure (1), the reaction of compound 14
the ratio 47:53 ( F NMR) was added. Resulting mixture was
stirred at 20 8C for 21 h. Then upper phase (1.46 g) consisting
of compound 46 was separated. The residue treated analo-
gously to the previous procedure gave 3.99 g of mixture, which
3
4
5
(
0.67 g), CF COOH (0.31 g) and SbF (1.75 g) (molar ratio,
3 5
1
(
:1:3) gave (20 8C, 1.5 h) 0.53 g of mixture, which contained
1
9
19
F NMR) compounds 15 and 16 in the ratio 96:4 (yield
4% and 3%, respectively).
. Analogously to procedure (1), the reaction of compound 14
contained (GLC, F NMR) 62% (yield 98%) of 26 and 38% of
8
46. The individual ketone 26 (0.31 g) was isolated from the
mixture (0.9 g) by silica gel column chromatography (hexane
as eluent).
(
0.87 g), CF COOH (0.56 g) and SbF (2.29 g) (molar ratio,
3 5
1
(
:1.4:3) gave (20 8C, 2 h) 0.67 g of mixture, which contained
1
9
F NMR) compounds 15 and 16 in the ratio 84:16 (yield
2% and 14%, respectively).
. A mixture of compound 14 (0.38 g, 1.53 mmol), CF COOH
3.5.3.1. Perfluoro-2,2-diethylbenzocyclobuten-1-one
7
(26). Liquid. UV (hexane) lmax, nm (lg e): 210 (4.15), 242
ꢀ
(3.96), 249 (4.00), 279 (2.85), 286 (2.85). IR (CCl ) n, cm :
4
1
3
1
9
(
0.18 g, 1.58 mmol) and SbF (1 g, 4.61 mmol) was kept at
5
1834 (C O); 1523, 1484 (FAR). F NMR (CH Cl ): d ꢀ81.5
2
2
2
was added and the resulting mixture was heated for 24 h at
0 8C for 24 h. Then more CF COOH (0.24 g, 2.11 mmol)
(6F, m, 2CF ), ꢀ111.6 (4F, m, 2CF ), ꢀ125.6 (1F, F-6), ꢀ133.0
3,4
3
3 2
(1F, F-4), ꢀ133.4 (1F, m, F-3), ꢀ142.9 (1F, F-5); J = 19,
3,5 3,6 4,5 4,6 5,6
2
hydrochloric acid and extracted with CHCl . The solvent
0 8C and for 6 h at 40 8C. The mixture was poured into 5%
J = 8, J = 23, J = 17, J = 13, J = 20. HRMS m/z,
425.9729 (M ). Calcd for C F O = 425.9725.
+
3
12 14
was distilled off to give 0.29 g of mixture, which contained
1
9
(
F NMR) 18% (yield 16%) of 15, 69% (63%) of 16 and
3% of unidentified impurities.
. Analogously to procedure (2), the reaction of compound 14
3.5.4. Perfluoro-1-methylindan (21)
Analogously to procedure (Section 3.5.1), the reaction of
compound 21 (0.3 g), CF COOH (0.24 g) and SbF (1 g)
1
6
3
5
(
0.9 g), CF COOH (0.99 g) and SbF (2.35 g) (molar ratio,
5
(molar ratio, 0.6:1.4:3) gave (20 8C, 3 h) 0.27 g of ketone 27
(yield 96%).
3
1
:2.4:3) gave (95 8C, 28 h) after sublimation (150 8C, 2 Torr)
.73 g of acid 17 (yield 85%).
0
3.5.4.1. Perfluoro-3-methylindan-1-one (27). Liquid. UV
3.5. Reaction of perfluorinated alkylbenzocycloalkenes
with CF COOH/SbF
(hexane) lmax, nm (lg e): 214 (4.13), 245 (3.98), 252 (4.02),
ꢀ
286 (3.18), 293 (3.20). IR (CCl ) n, cm : 1776 (C O); 1515
4
1
3
5
1
9
(
FAR). F NMR (CH Cl ): d ꢀ76.1 (3F, CF ), ꢀ118.0 (1F )
2
2
3
A
3
.5.1. Perfluoro-1-methylbenzocyclobutene (18)
A mixture of compound 18 (2.67 g), CF COOH (1.43 g)
and ꢀ126.9 (1F , CF -2), ꢀ132.1 (1F, F-7), ꢀ132.9 (1F, F-4),
B 2
ꢀ134.9 (1F, F-5), ꢀ142.7 (1F, F-6), ꢀ177.3 (1F, F-3);
¼ 2, ¼ 16, ¼ 10,
3
and SbF (5.82 g) (molar ratio, 1:1.4:3) was kept at 20 8C for
J
J
J
J
5
CF ꢀFðAÞ
CF ꢀFðBÞ
3
CF ꢀFð3Þ
3
CF ꢀFð4Þ
3
3
2
h. The mixture was poured into 5% hydrochloric acid and
extracted with CH Cl . The extract was dried over MgSO . The
¼ 17, J = 285, J = 4, J = 4, J3,4 = 6, J = 4, J3,7 = 1,
A,B
A,3
B,3
3,6
J
= 20, J = 9, J4,7 = 18, J = 18, J5,7 = 13, J6,7 = 21.
4,5 4,6 5,6
2
2
4
+
solvent was distilled off to give 2.32 g of ketone 24 (yield
9
HRMS m/z, 325.9782 (M ). Calcd for C F O = 325.9789.
10 10
4%).
3
.5.5. Perfluoro-1-ethylindan (4)
Analogously to procedure (Section 3.5.1), the reaction of
compound 4 (1.25 g), CF COOH (0.5 g) and SbF (2.05 g)
3
.5.2. Perfluoro-1-ethylbenzocyclobutene (19)
A mixture of compound 19 (5.33 g), CF COOH (2.44 g) and
3
3
5
SbF (9.96 g) (molar ratio, 1:1.4:3) was kept at 20 8C for 2 h.
(molar ratio, 1:1.4:3) gave (20 8C, 5 h) 1.16 g of ketone 2 (yield
98%).
5
The mixture was poured into 5% hydrochloric acid. Organic
phase was separated and dried over MgSO to give 4.86 g of
ketone 25 (yield 97%).
4
3.5.5.1. Perfluoro-3-ethylindan-1-one (2). Liquid. UV (hex-
ane) lmax, nm (lg e): 213 (4.20), 251 (4.00), 293 (3.24). IR
ꢀ
(CCl ) n, cm : 1783 (C O); 1513 (FAR). F NMR (CHCl ): d
4 3
1
19
3
.5.2.1. Perfluoro-2-ethylbenzocyclobuten-1-one
(25). Li-
quid. UV (hexane) lmax, nm (lg e): 213 (4.25), 247 (3.98),
ꢀ80.4 (3F, CF ), ꢀ115.6 (1F ) and ꢀ127.4 (1F , CF -2,
3
A
B
2
ꢀ
1
73 (3.08). IR (CCl ) n, cm : 1830, 1813 (C O); 1522, 1483
2
J
A,B
= 278), ꢀ118.5 (1F ) and ꢀ120.9 (1F , CF CF ,
4
A
B
2
3
1
9
[
fluorinated aromatic ring (FAR)]. F NMR (CH Cl ): d ꢀ82.0
JA,B = 297), ꢁꢀ132. 4 (2F, F-4, F-7), ꢀ135.6 (1F, F-5);
2
2
+
(
3F, CF ), ꢀ122.3 (2F, CF ), ꢀ125.8 (1F, F-6), ꢀ132.2 (1F, F-
ꢀ142.8 (1F, F-6), ꢀ180.4 (1F, F-3). HRMS m/z, 375.9759 (M ).
3
2
3
J
J
), ꢀ133.0 (1F, F-4), ꢀ140.4 (1F, F-5), ꢀ155.9 (1F, F-2);
¼ 1, J ¼ 11, J ¼ 6, J ¼ 12,
Calcd for C F O = 375.9757.
11 12
CF ꢀCF
CF ꢀFð2Þ
CF ꢀFð3Þ
CF ꢀFð2Þ
3
2
3
3
2
¼ 3, J = 4, J = 2, J = 5, J = 2, J = 19,
3.5.6. Perfluoro-1,1-dimethylindan (22)
Analogously to procedure (Section 3.5.1), the reaction of
compound 22 (0.71 g), CF COOH (0.28 g) and SbF (1.16 g)
CF ꢀFð3Þ
2,3
2,4
2,5
2,6
3,4
2
J3 = 9, J = 25, J = 18, J4,6 = 12, J5,6 = 20. HRMS m/z,
4,5
,5
3,6
+
3
25.9795 (M ). Calcd for C F O = 325.9789.
10 10
3
5