Synthesis of 9,10-bis(trifluoromethyl)benzobarrelenes through reaction of hexafluorobut-2-yne and substituted naphthalenes

Article abstract of DOI:10.1016/j.jfluchem.2020.109450

The cycloadducts 9,10-bis(trifluoromethyl)benzobarrelenes were prepared by the reaction of hexafluorobut-2-yne (HFB) with 1- and, 2- substituted naphthalenes in moderate to high yields. In most cases the reaction proceeds with the formation of two isomeric products derived from cycloaddition of HFB to different aromatic rings of the naphthalene system. The individual isomers were isolated by column chromatography and fully characterized. The basic hydrolysis of ester derivatives of the various 9,10-bis(trifluoromethyl)benzobarrelenes provided the corresponding acids.

Full text of DOI:10.1016/j.jfluchem.2020.109450

JournalofFluorineChemistry232(2020)109450
Contents lists available at ScienceDirect
Journal of Fluorine Chemistry
journal homepage: www.elsevier.com/locate/fluor
Synthesis of 9,10-bis(trifluoromethyl)benzobarrelenes through reaction of
hexafluorobut-2-yne and substituted naphthalenes
Mikhail M. Kremleva, Oleksii I. Mushtaa, Yurii L. Yagupolskiia,*, Julia A. Rusanovab,
Sheng Pengc,*, Viacheslav Petrovc
a Institute of Organic Chemistry, National Academy of Sciences of the Ukraine, Murmanskaya St., 5, UA-02094, Kyiv, Ukraine
b Department of Chemistry, Taras Shevchenko National University of Kyiv, 64/13, Volodymyrska Str. Kyiv, 01601, Ukraine
c The Chemours Company, 200 Powder Mill Rd., Experimental Station Wilmington, DE, 19803, USA
A R T I C L E I N F O
A B S T R A C T
Keywords:
The cycloadducts 9,10-bis(trifluoromethyl)benzobarrelenes were prepared by the reaction of hexafluorobut-2-
yne (HFB) with 1- and, 2- substituted naphthalenes in moderate to high yields. In most cases the reaction
proceeds with the formation of two isomeric products derived from cycloaddition of HFB to different aromatic
rings of the naphthalene system. The individual isomers were isolated by column chromatography and fully
characterized. The basic hydrolysis of ester derivatives of the various 9,10-bis(trifluoromethyl)benzobarrelenes
provided the corresponding acids.
Benzobarrelene
Hexafluorobut-2-yne
1,4-Addition
Naphthalene derivatives
1. Introduction
It should be pointed out that all previously reported examples of
Benzobarrelenes belong to an interesting class of rigid cage com-
pounds, which have been used as diene ligands for the preparation of
transition-metal complexes [1] and also as monomers for ring-opening
metathesis polymerization [2]. Their utility however, is limited due the
limited number of known examples. Typically these materials are pre-
pared by [4 + 2] cycloaddition of alkynes with naphthalenes. Hexa-
fluorobut-2-yne (HFB) is a highly reactive dienophile which undergoes
cycloaddition reactions with substrates such as furan [3], anthracene
[4] and even electron-rich benzenes [5]. The reactions of HFB with
naphthalene proceeds at elevated temperature [6,7]. For example, the
reaction with naphthalene (225 °C, 1.5 h) resulted in isolation of the
corresponding 9,10-bis(trifluoromethyl)benzobarrelene in 37 % yield
[7]. The similar reaction of 2,3,6,7-tetrakis-(trifluoromethyl)naphtha-
lene (225 °C, 800 atm pressure over 16 h) gave the cycloaddition
product in 79 % yield [7].
9,10-bis(trifluoromethyl)benzobarrelenes were derived from the reac-
tion of symmetric naphthalenes and HFB.
In continuation of our ongoing studies [8] of HFB chemical behavior
we studied the reaction of HFB with various non-symmetrical naphtha-
lene derivatives, including 1- and 2-naphthol, 1-acetoxynaphthalene,
methyl esters of 1- and 2-naphthylacetic acid, and 1- and 2-naphthyl
carboxylic acids. The results of this study are reported in this article.
2. Results and discussion
The reaction of excess HFB and naphthalenes was carried out at 195
оC under - autogenous pressure (see Experimental). Various non-sym-
metrical 1- and 2- substituted naphthalenes (R = −OH, −CH2C(O)
OMe and –C(O)OMe substituents) were subjected to the reaction with
excess of HFB.
⁎ Corresponding authors.
E-mail addresses: yagupolskii@ioch.kiev.ua (Y.L. Yagupolskii), sheng.peng@chemours.com (S. Peng).
https://doi.org/10.1016/j.jfluchem.2020.109450
Received 25 September 2019; Received in revised form 16 December 2019; Accepted 18 December 2019
Availableonline23January2020
0022-1139/©2020ElsevierB.V.Allrightsreserved.

M.M. Kremlev, et al.
JournalofFluorineChemistry232(2020)109450
Table 1
Yields and ratios of products derived from cycloaddition of HFB and with 1- and 2- substituted naphthalenes.
a
a
Entry
Starting naphthalene (2), (5)
Product (3), (6)
Product (4), (7)
Total yield, % (ratio (3)/(4) (6)/(7))
Yield of (3), (6), %
Yield of (4), (7), %
1
88 (1 : 1)
29
14
16
40
31
25
30
25
2a
3a
4a
2
3
4
71 (1 : 3)
82 (1 : 3)
94 (3 : 1)
2b
2c
3b
3c
4b
4c
5a
7a
7b
6a
5
6
89 (1 : 3)
17
4
41
63
5b
5c
6b
89 (1 : 10)
7c
6c
7
a
87 (1 : 0)
87
7d
5d
6d
Isolated yields (column chromatography followed by crystallization).
In case of naphthalenes carrying a substituent at the 2 position [2a
(R= −OH), 2b (R= −CH2C(O)OMe) and 2c (R= –C(O)OMe)) high
yields (71–88%) were obtained for the corresponding isomeric barre-
lenes 3a-c and 4a-c, resulting from cycloaddition of one mole HFB to
either substituted or non-substituted aromatic ring of naphthalene
system. These yields are in contrast to the low yield of HFB cycload-
dition to unsubstituted naphthalene [7], thus we repeated this experi-
ment, changing time and concentration but the yield of key product was
still in the range of 37–39 %. We assume that the specificity of this case,
in contrast to all other examples, is the volatility of naphthalene in
comparison to substituted derivatives.
(89–94 %) of benzobarrelenes 6a-c/7a-c. Interestingly, in the case of 1-
naphthol (5a) the isomer 6a was predominant (6a/7a - 3:1, Scheme 2,
Table 1), while the cycloaddition of HFB to 5b and 5c proceeded with
predominant formation of isomers 7b and 7c. In case of methyl 1-
naphthoate (5d) the reaction was regioselective, leading to exclusive
formation of the adduct 6d (87 % yield), derived from an addition of
the acetylene to the substituted aromatic ring (see Table 1). Using
column chromatography individual isomers were isolated and in the
case of isomers 6b and 7b the structures was confirmed by X-ray dif-
fraction.
The 2,3-bis(trifluoromethyl)bicyclo(2.2.2)oct-2-ene fragment in 6b
and 7b (Fig. 1) has very similar geometric parameters. The average
interatomic distances and bond angles are typical of those for known
hydrocarbon analogues - [9,10] and correlated to standard values ty-
pical for corresponding carbon-carbon bonds. For example, the dis-
tances between C8 and C9 and C11 and C12 carbons (see Fig. 1) in these
compounds have values in the range 1.309(3)-1.333(3) typical for
standard C]C double bond in organic compounds. Bond distances and
angles for aromatic rings and Csp3 hybridized carbon atoms are also
within standard values. The notable exception is the significant increase
of the C12-C11-C13 and C11-C12-bond angles (124.49(17)-
129.43(17)°) caused by the intramolecular CF3-CF3 repulsion.
It should be also pointed out, that despite that an excess HFB was
While in case of 2-naphthol (2a) the reaction resulted in high yield
formation of two isomeric products 3a and 4a (ratio 1:1), the cy-
cloaddition of HFB to 2-naphthylacetic acid (2b) and 2-naphthyl car-
boxylic acid (2c) led to formation of cycloadducts 3b/4b and 3c/4c,
with predominant formation of cycloadducts at the unsubstituted aro-
matic ring (4b-c Sch. 1, Table 1). It is necessary to note that while high
reaction temperatures were employed the various functional groups
were found to be stable to these reaction conditions (Scheme 1).
The same peculiarities were found in the reaction of naphthalenes
with substituents at the 1 position (Sch. 2).
The reaction of HFB with 1-naphthol (5a), 1-naphthyl acetate (5b),
and the methyl ester of 1-naphthylacetic acid (5c) led to high yields
Scheme 1. The cycloaddition reaction of HFB with 2-substituted naphthalenes. i) 195 °C, 16 h.
2

M.M. Kremlev, et al.
JournalofFluorineChemistry232(2020)109450
Scheme 2. The Diels-Alder reaction of HFB with 1-substituted naphthalenes. i) 195 °C, 16 h.
Fig. 1. Molecular structure of 6b and 7b.
particular case the cyclization resulted in the formation of six-mem-
bered ring that was proved by NMR data.
Esters of benzobarrelenes 3b, 4(b,c), 6(c,d), 7c were hydrolyzed to
the corresponding acids 10–13 upon treatment with NaOH, followed by
acidification (Scheme 4, Table 2).
The hydrolysis of compound 6b gave alcohol 6a, prepared from the
1-naphthol (See Scheme 2) which was identified by 1H, 19F NMR
spectroscopy. Similarly, the hydrolysis of compound 7b gave alcohol
7a, which was identical to the material isolated in the cycloaddition
reaction with 1-naphthol (Sch. 5, Table 2) (Scheme 5).
Scheme 3. The reaction of HFB with 1,8-naphthalenediamine. i) 195 °C, 8 h.
Hydrolysis of compound (3c) in the mixture NaOH, water, methanol
and THF gave product 14 (Scheme 6) as a result of Michael type ad-
dition of MeOH to the double bond of either compound 3c (followed by
hydrolysis), or to compound 15. Noteworthy to mention that acid 15
was isolated in high yield when the hydrolysis was carried out in the
absence of methanol (Sch. 6).
used in all experiments involving naphthalenes the formation of
double-addition products was never observed in these reactions.
An attempt to react HFB with 1,8-naphthalenediamine led to a very
different result. This reaction resulted in selective formation of cyclic
product 9, derived from nucleophilic addition of the amino groups of 8
across the electrophilic triple bond of HFB (Scheme 3).
Although this type of nucleophilic reactions of fluorinated olefins
often results in the formation of seven-membered rings [11], in this
3. Conclusion
Hexafluorobutyne-2 undergoes cycloaddition with various naph-
thalenes resulting in the formation of 1:1 cycloadducts - the corre-
sponding 9,10-bis(trifluoromethyl)benzobarrelenes isolated tin mod-
erate to high yields It was found that in case of nonsymmetrical
naphthalenes the reactions was not regioselective and proceed with
formation of two isomeric products as a result of HFB cycloaddition to
both aromatic rings of the naphthalene system. The ratio of regioi-
somers varies significantly depending on the naphthalene substitution
pattern and character of the substituents.
Scheme 4. Hydrolysis of esters3b, 4(b,c), 6(c,d), 7c. i) NaOH, H2O/MeOH/
THF-1:1:4, r.t.; ii) conc. HCl.
3

M.M. Kremlev, et al.
JournalofFluorineChemistry232(2020)109450
Table 2
Stuart melting point apparatus SMP10. Elemental analyses were carried
out in the Analytical Laboratory of the Institute of Organic Chemistry,
NAS of Ukraine, Kyiv; analytically pure samples were prepared by
crystallization of small amount of the product. Purification of products
by column chromatography was performed using Silica Gel, (70–230
mesh, Aldrich), column: L=350 mm, D =30 mm and hexane/di-
chloromethane 6:4 (by weight) as eluent. Esters were prepared ac-
cording to standard procedure from corresponding naphthyl acetic
acids and naphthyl carboxylic acids by reflux with methanol in the
presence of sulfuric acid.
Hydrolysis of esters 3b, 4(b,c), 6(b–d), 7(b,c).a
Entry
Starting ester
Product
Yield, %
92
1
3b
4c
10
2
3
4
89
90
89
4b
11b
11c
All crystallographic measurements were performed at temperature
173 K on a Bruker Smart Apex II diffractometer operating in the ω scans
mode. The structure were solved by direct methods and refined by the
full-matrix least-squares technique in the anisotropic approximation for
non-hydrogen atoms using the Bruker SHELXTL program package [12].
Full crystallographic details have been deposited at Cambridge Crys-
tallographic Data Centre CCDC. Any request to the CCDC for these
materials should quote the full literature citation and reference number
CCDC 1,953,290 and CCDC 1,953,291.
6a
6b
5
6
89
92
6c
12c
6d
7c
12d
4.1. General procedure of 1,4-addition of hexafluorobut-2-yne to
naphthalene derivatives
7
8
91
91
7a
7b
A mixture of 0.03 mol corresponding naphthalene derivative and
0.06 mol of hexafluorobut-2-yne was heated at 190−195 °C for 16 h (8
h for 1,8-naphthalenediamine) in a 100 ml stainless steel autoclave
fitted with magnetic stirrer under autogenous pressure - given the moles
of reagents (0.09 mol total), temperature (195 C), and reactor volume
(100 mL) the maximum pressure in the reactor would be 34.5 bar (ca.
525 psig). Autoclave was cooled to ambient temperature and volatile
product was removed. The reaction mixture was extracted with di-
chloromethane and then solvent was removed under reduced pressure.
The crude product thus obtained was subjected to separation by column
chromatography and the isolated individual isomers were further pur-
ified by recrystallization. However, products (5) and (9) were purified
only by crystallization.
13
a
Conditions: NaOH (12 mmol), H2O (5 mL), MeOH (5 mL), THF (20 mL),
r.t., 48 h.
Scheme 5. Hydrolysis of esters 6b, 7b. i) NaOH, H2O/MeOH/THF-1:1:4, r. t.;
ii) conc. HCl.
4.2. 11,12-Bis(trifluoromethyl)tricyclo(6.2.2.02,7)dodeca-2,4,6,11-
tetraen-9-on (3a)
Colorless crystals, yield 29 %. m.p. 39−40 °C. (from pentane); 1H
NMR (400 MHz, CDCl3): δ 2.15 (d, 1H, 2JHH =18 Hz, CH2), 2.31 (d, 1H,
2JHH =18 Hz, CH2), 4.60 (s, 1H, H-8), 4.81 (s, 1H, H-1), 7.35 (m, 4H,
arom. H-3,4,5,6). 13C NMR (125.71 MHz, CDCl3): δ 200.0 (s, C-9, C =
O), 140.7 (qq, 2JCF =35.4 Hz, 3JCF =4 Hz, C-12,(11), CF3C=), 138.7 (s,
4. Experimental
NMR spectra of compounds isolated were recorded on a Varian
UNITY- Plus 400 (1H, 399.98 MHz, 19F, 376.49 MHz) and 13C NMR-
spectra were recorded on a Bruker AVANCE DRX 500 instrument at
125.71 MHz in CDCl3 (DMSO-d6 for compounds 10,15) solutions. The
chemical shifts are given in units of δ (ppm) using external standards
(1H, 13C Me4Si, 19F: CCl3F). Melting points were determined using a
2
3
2C, arom. C-2,7), 136.15 (qq, JCF =35.4 Hz, JCF =4 Hz, C-11(12),
CF3C=), 133.9 (s, 2C, arom. C-2,7) 128.7 (s, arom. C), 127.9 (s, arom.
1
C), 125.9 (s, arom. C), 124.3 (s, arom. C), 121.1 (q, JCF =271.8 Hz,
CF3), 120.9 (q, 1JCF =271.8 Hz, CF3), 59.0 (s, C-8(1)), 41.58 (s, C-1(8)),
Scheme 6. Hydrolysis of 3c i) NaOH, H2O/MeOH/THF-1:1:4, r. t.; ii) conc. HCl; iii) NaOH, H2O /THF-1:4, r. t.
4

M.M. Kremlev, et al.
JournalofFluorineChemistry232(2020)109450
34.2 (s, C-10, CH2). 19F NMR (376.49 MHz, CDCl3): δ -61.04 (q, 3 F,
4.7. Methyl [9,10-bis(trifluoromethyl)tricyclo(6.2.2.02,7)dodeca-2,4,6,9,11-
pentaen-3-yl] carboxylate (4c)
2JFF =11.2 Hz, CF3), -62.64 (q, 3 F, JFF =11.2 Hz, CF3). Analysis:
2
Found: %C 54.98; %H 2.70. C14H8F6O. Calcd.: %C 54.91; % H 2.63.
Colorless crystals, yield 30 %; m.p. 96−97 °C (from hexane); 1H
NMR (400 MHz, CDCl3): δ 3.85 (s, 3H, CH3), 5.25 (m, 2H, H-1,8), 6.98
4.3. Methyl [11,12-bis(trifluoromethyl)tricyclo(6.2.2.02,7)dodeca-2,4,6,9,11-
pentaen-9-yl] acetate (3b)
3
(m, 2H, H-11,12), 7.32 (d, 1H, JHH =7.5 Hz arom. H-6), 7.73 (d, 1H,
3JHH =7.5 Hz, arom. H-5), 7.91 (s, 1H, arom. H-3); 13C NMR (125.71
MHz, CDCl3): δ 166.6 (C = O), 148.7 (s, arom. C-7(2)), 144.3 (s, arom.
C-2(7)), 144.2 (m, C-9,10, 2CF3C=), 139.5 (s, C-12(11), CH=), 139.2
(s, C-11(12), CH=), 127.5 (s, arom. C), 127.4 (s, arom. C), 124.0 (s,
Colorless oil, yield 14 %; 1H NMR (400 MHz, CDCl3): δ 3.57 (s, 2H,
CH2), 3.68 (s, 3H, CH3), 5.21 (m, 2H, H-1,8), 6.93 (d, 1H, 3JHH =6 Hz,
H-10), 6.99 (m, 2H, arom. H), 7.25 (m, 2H, arom. H). 13C NMR (125.71
MHz, CDCl3): δ 170.2 (s, C = O), 146.4 (s, arom. C-2(7)), 144.5 (m, C-
11(12), CF3C=), 144.2 (m, C-12(11), CF3C=), 143.9 (s, arom. C-2(7)),
143.5 (s, C-9(10), CH=), 135.0 (s, C-10(9), CH=), 125.0 (s, arom. C),
123.5 (s, arom. C), 123.1 (s, arom. C), 122.1 (q, 1JCF =271.8 Hz, 2CF3),
52.9 (s, CH3O), 52.0 (s, C-8(1)), 48.8 (s, C-1(8)), 37.9 (s, CH2). 19F
(376.49 MHz, CDCl3): δ -61.78 (q, 3 F, 2JFF 11.2 Hz CF3,), -61.89 (q., 3
F, CF3, 2JFF 11,2 Hz). Analysis: Found: %C 56.26; %H 3.04. C17H12F6O2.
Calcd.: %C 56.36; % H 3.34.
1
arom. C), 123.1 (s, arom. C), 121.7 (q, JCF =273.8 Hz, 2CF3), 52.1 (s,
C(O)OCH3), 49.0 (s, C-8(1)), 48.9 (s, C-1(8)). 19F NMR (376.49 MHz,
CDCl3): δ -62.42 (br. s, 6 F, 2CF3). Analysis: Found: %C 56.31; %H 2.95.
C
10H10F6O2. Calcd.: %C 55.18; % H 2.89.
4.8. 9,10-Bis(trifluoromethyl)tricyclo(6.2.2.02,7)dodeca-2,4,6,9,11-pentaen-
1-ol (6a)
Colorless crystals yield 40 %, m.p. 62−64 °C (from pentane); 1H
NMR (400 MHz, CDCl3): δ 3.33 (br. s, OH), 5.22 (d, 1H, 3JHH =6.0 Hz,
H-8), 6.87 (d, 1H, 3JHH = 7.2 Hz, H-11), 7.12 (m, 4H, arom. H-3,4,5,6),
4.4. Methyl [11,12-bis(trifluoromethyl)tricyclo(6.2.2.02,7)dodeca-2,4,6,9,11-
pentaen-9-yl] carboxylate (3c)
7.51 (d, 1H, JHH = 7.2 Hz, H-12). 13C NMR (125.71 MHz, CDCl3): δ
3
145.7 (qq, 2JCF =31 Hz, 3JCF =4 Hz, C-10(9), CF3C=), 145.0 (s, arom.
C), 144.0 (qq., 2JCF =31 Hz, 3JCF =4 Hz, C-9(10), CF3C=), 143.7 (s, C-
12(11), CH=), 141.7 (arom. C), 137.2 (s, C-11(12), CH=), 125.3 (s,
arom. C), 125.1 (s, arom. C), 123.0 (s, arom. C), 122.8 (q, 1JCF =278.8
Yellow oil, yield 16 %; 1H NMR (400 MHz, CDCl3): δ (ppm) 3.77 (s,
3
3H, CH3), 5.32 (d, 1H, JHH =6 Hz, H-1), 5.75 (s, 1H, H-8), 7.06 (m,
2H, arom. H), 7.36(m, 1H, arom. H), 7.41(m, 1H, arom. H), 7.79 (d, 1H,
3JHH =6 Hz, H-10). 13C NMR (125.71 MHz, CDCl3): δ 163.2 (C = O),
147.0 (s, arom. C-7(2)), 144.3 (s, arom. C-2(7)), 144-143.4 (m, 2C-
11(12), 2CF3C=), 142.5 (s, C-9(10), CH=), 141.5 (s, C-10(9), CH=),
125.3 (s, arom. C), 125.1 (s, arom. C), 123.6 (s, arom. C), 123.5 (s,
1
Hz, CF3), 122.6 (q, JCF =272.8 Hz, CF3), 119.4 (s, arom. C), 84.0 (s,
C−OH), 47.0 (s, CH). 19F NMR (376.49 MHz, CDCl3): δ -59.20 (q, 3 F,
3
3JFF =11.2 Hz, CF3), -60.54 (q, 3 F, JFF =11.2 Hz, CF3). Analysis:
Found: %C 54.90; %H 2.67. C14H8F6O. Calcd.: %C 54.91; % H 2.63.
1
1
arom. C), 121.3 (q, JCF =273.1 Hz, CF3), 121.2 (q, JCF =273.1 Hz,
CF3), 51.7 (s, C, CH3O), 48.9 (s, C-8(1)), 48.2 (s, C-1(8)). 19F NMR
(376.49 MHz, CDCl3): δ -61.83 (br. s, 6 F, 2CF3). Analysis: Found: %C
55.30; %H 3.03. C16H10F6O2. Calcd.: %C 55.18; % H 2.89.
4.9. 9,10-Bis(trifluoromethyl)tricyclo(6.2.2.02,7)dodeca-2,4,6,9,11-pentaen-
1-yl acetate (6b)
Colorless crystals, yield 17 %, m.p. 106−108 °C (from pentane); 1
H
3
NMR (400 MHz, CDCl3): δ 2.43 (s, 3H, CH3), 5.20 (d, 1H, JHH =6.6
4.5. 10-Bis(trifluoromethyl)tricyclo(6.2.2.02,7)dodeca-2,4,6,9,11-pentaen-4-
ol (4a)
3
Hz, H-8), 6.93 (t, 1H, JHH =6.9 Hz, 6.6 Hz, arom. H-4), 7.10 (m., 3H,
H arom., H-3,5,6), 7.30 (d, 1H, 3JHH = 6.6 Hz, H-11), 7.40 (d, 1H, 3JHH
= 6.6 Hz, H-12). 13C NMR (125.71 MHz, CDCl3): δ 169.3 (s, C = O),
144.2 (m, 2C, C-10,9, 2CF3C=), 142.0 (s, arom. C-7(2)), 141.2 (s, C-
11(12), CH=), 141.2 (s, arom. C-2(7)), 134.2 (s, C-12(11), CH=),
125.6 (s, arom. C), 125.06 (s, arom. C), 123.1 (s, arom. C), 121.6 (q,
1JCF =272.8 Hz, CF3), 121.0 (q, 1JCF =278.8 Hz, CF3), 120.7 (s, arom.
C), 86.2 (s, C-O), 47.4 (s, CH), 21.2 (s, CH3). 19F NMR (376.49 MHz,
Colorless crystals, yield 31 % m.p. 72−74 °C (from pentane); 1H
NMR (400 MHz, CDCl3): δ 4.76 (br.s, 1H, OH), 5.13 (m, 2H, H-1,8),
3
3
3
6.42 (dd, 1H, JHH =7.6 Hz, JHH =2.4 Hz, H-5), 6.84 (d, 1H, JHH
3
=2.4 Hz, H-3), 6.97 (m, 2H, H-11,12), 7.10 (d, 1H, JHH =7.6 Hz,
arom, H-6). 13C NMR (125.71 MHz, CDCl3): δ 152.9 (s, arom. C), 146.0
(s, arom. C), 144.9 (m, C-9(10), CF3C=), 144.2 (m, C-10(9), CF3C=),
139.8 (s, C-11(12), CH=), 138.7 (s, C-12(11), CH=), 136.2 (s, arom.C),
123.0 (s, arom. C), 122.0 (q, 1JCF =272.8 Hz, 2CF3), 112.1 (s, arom. C),
110.5 (s, arom. C), 48.9 (s, C-8(1)), 48.3 (s, C-1(8)). 19F NMR (376.49
MHz, CDCl3): δ -61.95 (m, 3 F, CF3), -62.05 (m, 3 F, CF3). Analysis:
Found: %C 54.85; %H 2.58. C14H8F6O. Calcd.: %C 54.91; % H 2.63.
3
3
CDCl3): δ -59.69 (q, 3 F, JFF =12.7 Hz, CF3), -61, 65 (q, 3 F, JFF
=12.7 Hz, CF3). Analysis: Found: %C 55.12; %H 2.83. C16H10F6O2.
Calcd.: %C 55.18; % H 2.89.
4.10. Methyl [9,10-bis(trifluoromethyl)tricyclo(6.2.2.02,7)dodeca-2,4,6,9,11-
pentaen-1-yl] acetate (6c)
4.6. Methyl [9,10-bis(trifluoromethyl)tricyclo(6.2.2.02,7)dodeca-2,4,6,9,11-
pentaen-4-yl] acetate (4b)
Colorless crystals, yield 4 %; m.p. 72−73 °C (from pentane); 1H
NMR (400 MHz, CDCl3): δ 3.60 (d, 1H, HA, 2JHH =18 Hz, CH2), 3.77 (d,
1H, HB, 2JHH =18 Hz, CH2), 3.80 (s, 3H, CH3), 5.22 (d, 1H, 3JHH =5.6
Hz, H-8), 7.03 (m., 4H, arom. H-3,4,5,6), 7.23 (d, 1H, 3JHH =7.6 Hz, H-
11), 7.31 (d, 1H, 3JHH =7.6 Hz, H-12). 13C NMR (125.71 MHz, CDCl3):
Colorless oil, yield 25 %; 1H NMR (400 MHz, CDCl3): δ 3.30 (s, 2H,
CH2), 3.68 (s, 3H, CH3), 5.13 (m, 2H, H-1,8), 6.68 (d, 1H, 3JHH =6 Hz,
arom. H-3) 7.03 (m, 2H, H-11,12), 7.32 (m, 2H, arom. H-5,6). 13C NMR
(125.71 MHz, CDCl3): δ 170.2 (s, C = O), 146.4 (s, C-12(11), CH=),
144.26 (m, C-10,9, 2CF3C=), 143.9 (s, arom. C-2(7)), 143.5 (s, arom.
C-7(2)), 135.0 (s, C-11(12), CH=), 125.24 (s, arom. C), 125.2(s, arom.
2
3
δ 171.0 (s, C = O), 147.8 (qq, JCF =34 Hz, JCF =4.1 Hz, C-10(9),
2
3
CF3C=), 145.1 (s, arom. C-7(7)), 144.6 (qq, JCF =34 Hz, JCF =4.1
Hz, C-9(10), CF3C=), 143.3 (s, C- 12(11), CH=), 137.7 (s, C-11(12),
CH=), 125.0 (s, arom. C), 124.9 (s, arom. C), 123.4 (s, arom. C), 122.3
1
1
1
C), 123.5 (s, arom. C), 123.1 (s, arom. C), 122.0 (q, JCF =271.5 Hz,
(q, JCF =273.4 Hz, CF3), 122.1 (q, JCF =273.4 Hz, CF3), 121.2 (s,
2CF3), 52.9 (s, C-8(1)), 52.0 (s, CH3), 48.7 (s, C-1(8)), 39.7 (s, CH2). 19
F
arom. C), 53.9 (s, CH3O), 52.0 (s, C-8(1)), 48.6 (s, C-1(8)), 34.2 (s, CH2)
2
1
NMR (376.49 MHz, CDCl3): δ -61.43 (q, 3 F, JFF =11.2 Hz, CF3),
19F NMR (376.49 MHz, CDCl3): δ -57.53 (q, 3 F, JFF =11.2 Hz, CF3),
2
1
-62.87 (q, 3 F, JFF =11.2 Hz, CF3). Analysis: Found: %C 56.40; %H
-60.12 (q, 3 F, JFF =11.2 Hz, CF3). Analysis: Found: %C 56.38; %H
3.48. C17H12F6O2. Calcd.: %C 56.36; % H 3.34.
3.23. C17H12F6O2. Calcd.: %C 56.36; % H 3.34.
5

M.M. Kremlev, et al.
JournalofFluorineChemistry232(2020)109450
δ -61.79 (q, 3 F, JFF =11.2 Hz, CF3), -62.20 (q, 3 F, JFF =11.2 Hz,
CF3). Analysis: Found: %C 56.47; %H 3.25. C17H12F6O2. Calcd.: %C
56.36; % H 3.34.
4.11. Methyl [9,10-bis(trifluoromethyl)tricyclo(6.2.2.02,7)dodeca-2,4,6,9,11-
pentaen-1-yl] carboxylate (6d)
3
3
Colorless crystals, yield 87 %, m.p. 99−100 °C (from hexane); 1H
3
NMR (400 MHz, CDCl3): δ 3.96 (s, 3H, CH3), 5.27 (d, 1H, JHH = 5.2
4.15. 2-(2,2,2-Trifluoroethenyl)-2-(trifluoromethyl)-2,3-dihydro-1H-
perimidine (9)
3
Hz H-8), 6.68 (d, 1H, JHH = 5.2 Hz, H-11), 6.99 (m, 1H, H-12), 7.08
3
(m, 2H, arom. H-4,5), 7.44 (d, 1H, JHH =8 Hz, arom. H-3), 7.65 (d,
3
1H, JHH =8 Hz, arom. H-6); 13C NMR (125.71 MHz, CDCl3): δ 166.7
Yellow crystals, yield 67 %, m.p. 128−129 °C (from hexane); 1H
2
(s, C = O), 145.8 (s, arom. C-7(2)), 144.25 (s, arom. C) 144.6 (m, 2C, C-
9,10, 2CF3C=), 139.8 (s, C-12(11), CH=), 139.2 (s, C-11(12), CH=),
126.9 (s, arom. C), 126.6 (s, arom. 2C), 125.8 (s, arom. C-2(7)), 124.8
NMR (400 MHz, CDCl3): δ 2.73 (d, 1HA, JHH =10 Hz, CH2), 2.77 (d,
2
3
1HB, JHH =10 Hz, CH2), 4.68 (br. s, 2H, 2NH), 6.58 (d, 2H, JHH =7
Hz, arom. H), 7.26 (m, 4H, arom. H). 13C NMR (125.71 MHz, CDCl3): δ
136.5 (s, arom. C), 133.9 (s, arom. C), 127.1 (s, arom. C), 124.6 (q, 1JCF
1
(s, arom. C), 121.9 (q, JCF =273.4 Hz, 2CF3), 52.1 (s, CH3O), 49.1 (s,
C-1(8)), 45.7 (s, C-8(1)). 19F NMR (376.49 MHz, CDCl3): δ -62.36 (q, 3
=277.7 Hz, CF3), 124.7 (q, JCF =277.7 Hz, CF3), 118.5 (s, arom. C),
1
3
3
F, JFF =11.2 Hz, CF3), -62.56 (q, 3 F, JFF =11.2 Hz, CF3). Analysis:
105.8 (s, arom. C), 67.2 (q, 2JCF =28.9 Hz, CN), 38.4 (q, 2JCF =28.9 Hz,
CH2). 19F NMR (376.49 MHz, CDCl3): δ -59.68 (s, 3F, C-CF3), -83.23 (s,
3F, CH2CF3). Analysis: Found: %C 52.46; %H 3.13, %N 8.70.
Found: %C 55.17; %H 2.94. C16H10F6O2. Calcd.: %C 55.18; % H 2.89.
4.12. 9,10-Bis(trifluoromethyl)tricyclo(6.2.2.02,7)dodeca-2,4,6,9,11-
pentaen-3-ol (7a)
C14H10F6N2. Calcd.: %C 52.51; % H 3.15; %N 8.75.
4.16. General procedure of hydrolysis of compounds (3–7)
Colorless crystals, yield 25 %, m.p.100−101 °C (from pentane); 1H
NMR (400 MHz, CDCl3): δ 4.80 (br. s, 1H, OH), 5.22 (t, 1H, 3JHH =2.0
Hz, H-8), 5.65 (t, 1H, JHH =2.0 Hz, H-1), 6.47 (d, 1H, 3JHH =8.0 Hz, H-
A mixture of 0.006 mol of corresponding ester, 0.012 mol of NaOH
in 5 ml of water, 5 ml methanol [for preparation of acid (15) without
methanol] and 20 ml THF was stirred at ambient temperature for 48 h.
The reaction mixture was evaporated under reduced pressure to 30 % of
starting volume and was added to 20 ml of water. The mixture was
washed with diethyl ether (2 × 10 ml). Water extract was acidified to
pH 3–4 and organic acid was extracted with diethyl ether. The ether
solution was dried with MgSO4 and solvent was removed under reduced
pressure. The product was purified by crystallization.
3
3
11), 6.87 (t, 1H, JHH = 7.6 Hz, H-4), 6.94 (d, 1H, JHH =8.0 Hz, H-
12), 7.0 (t, 3H, JHH =2.4 Hz, arom. H-5,6). 13C NMR (125.71 MHz,
CDCl3): δ 150.0 (s, arom. C-7(2)), 146.9 (s, arom. C-2(7)), 144.6 (m, 2C,
C-9,10, 2CF3C=), 139.5 (s, C-12(11), CH=), 139.1 (s, C-11(12), CH=),
129.5 (s, arom. C), 126.1 (s, arom. C), 122.0 (q, 1JCF =272.8 Hz, 2CF3),
116.6 (s, arom. C), 113.9 (s, arom. C), 49.2 (s, C-8(1)), 42.6 (s, C-1(8)).
19F NMR (376.49 MHz, CDCl3): δ -61.50 (q, 3 F, JFF =11.2 Hz, CF3,),
3
3
-62.07 (q, 3 F, JFF =11.2 Hz, CF3). Analysis: Found: %C 54.97; %H
2.74. C14H8F6O. Calcd.: %C 54.91; % H 2.63.
4.17. 9,10-Bis(trifluoromethyl)tricyclo(6.2.2.02,7)dodeca-2,4,6,9,11-
pentaen-1-ol (6a)
4.13. 9,10-Bis(trifluoromethyl)tricyclo(6.2.2.02,7)dodeca-2,4,6,9,11-
pentaen-3-yl acetate (7b)
Colorless crystals, 89 % yield, m.p. 62−64 °C (from pentane).
Colorless crystals, yield 41 %, m.p. 69−70 °C (from pentane). 1H
4.18. 9,10-Bis(trifluoromethyl)tricyclo(6.2.2.02,7)dodeca-2,4,6,9,11-
pentaen-3-ol (7a)
3
NMR (400 MHz, CDCl3): δ 2.39 (s, 3H, CH3), 5.27 (d, 1H, JHH =5.6
Hz, H-8), 5.30 (d, 1H, 3JHH =5.6 Hz, H-1), 6.78 (d, 1H, 3JHH =8.0 Hz,
3
H-11), 7.0 (m, 3H, arom. H-4,5,6), 7.19 (d, 1H, JHH =8.0 Hz, H-12).
Colorless crystals, 91 % yield, m.p.100−101 °C (from pentane).
2
13C NMR (125.71 MHz, CDCl3): δ 169.0 (s, C = O), 147.8 (qq, JCF
3
=35.9 Hz, JCF =4 Hz, C-10(9), CF3C=), 146.2 (s, arom. C-3), 145.4
4.19. [11,12-Bis(trifluoromethyl)tricyclo(6.2.2.02,7)dodeca-2,4,6,9,11-
pentaen-9-yl] acetic acid (10)
2
3
(s, arom. C-2(7)), 145.0 (qq, JCF =35.9 Hz, JCF =4 Hz, C-9(10),
CF3C=), 139.8 (s, C-12(11), CH=), 135.4 (s, C-11(12), CH=), 135.4 (s,
1
arom. C-7(2)), 126.2 (s, arom. C), 122.0 (q, JCF =271.3 Hz, CF3),
Colorless crystals, 92 % yield, m.p. 110−111 °C (from hexane); 1H
NMR (400 MHz, DMSO-d6): δ 3.58 (s, 2H, CH2), 5.21 (m, 2H, H-1,8),
6.92 (d, 1H, 3JHH = 7.2 Hz, H-10), 6.99 (m, 2H, arom. H), 7.25 (m, 2H,
arom. H). 13C NMR (125.71 MHz, DMSO-d6): δ 177.8 (s, C = O), 145.0
(s, arom., C-7(2)), 144.3 (m, 2C, C-11,12, 2CF3C=), 143.1 (s, arom. C-
2(7)), 139.2 (s, C-10(9), CH=), 139.1 (s, C-9(10), CH=), 130.2(s,
arom. C), 126.0(s, arom. C), 124.5(s, arom. C), 123.0(s, arom. C), 122.1
121.8 (q, 1JCF =271.3 Hz, CF3), 120.9 (s, arom. C), 119.1 (s, arom. C),
48.99 (s, C-1(8)), 43.5 (s, C-8(1)), 20.7 (s, CH3) 19F NMR (376.49 MHz,
CDCl3): δ -62.0 (q, 3 F, 3JFF =11.2 Hz, CF3), -62.64 (q, 3 F, 3JFF =11.2
Hz, CF3). Analysis: Found: %C 55.38; %H 2.97. C16H10F6O2. Calcd.: %C
55.18; % H 2.89.
4.14. Methyl [9,10-bis(trifluoromethyl)tricyclo(6.2.2.02,7)dodeca-2,4,6,9,11-
pentaen-3-yl] acetate (7c)
(q, JCF =278.1 Hz, 2CF3), 48.9 (s, C-8(1)), 48.7 (s, C-1(8)), 40.6 (s,
1
3
CH2). 19F NMR (376.49 MHz, DMSO-d6): δ -62.59 (q, 3 F, JFF =11.2
3
Hz, CF3), -62.67 (q, 3 F, JFF =11.2 Hz, CF3). Analysis: Found: %C
Colorless oil, yield 63 %; 1H NMR (400 MHz, CDCl3): δ 3.70 (s, 3H,
CH3), 3.72 (d, 1HA, 2JHH =15.6 Hz, CH2), 3.80 (d, 1HB, 2JHH =15.6 Hz,
CH2), 5.24 (d, 1H, 3JHH = 5.2 Hz, H-8), 5.53 (d, 1H, 3JHH = 5.2 Hz, H-
55.09; %H 2.99. C16H10F6O2. Calcd.: %C 55.18; %H 2.89.
4.20. [9,10-Bis(trifluoromethyl)tricyclo(6.2.2.02,7)dodeca-2,4,6,9,11-
pentaen-4-yl] acetic acid (11b)
1), 6.95 (m, 2H, arom. H), 7.05 (m, 2H, H-11,12), 7.25(d, 1H, JHH
=
7.2 Hz arom. H). 13C NMR (125.71 MHz, CDCl3): δ 171.3 (s, C = O),
2
3
144.7 (qq, JCF =35.4 Hz, JCF =4.0 Hz, C-10(9), CF3C=), 144.5 (s,
arom. C-7(2)), 143.9 (qq, 2JCF =34 Hz, 3JCF =4.1 Hz, C-9(10), CF3C=),
143.1 (s, arom. C-2(7)), 139.5 (s, C-12(11), CH=), 139.0 (s, C-11(12),
CH=), 128.6 (s, arom. C), 126.8 (s, arom. C), 125.1 (s, arom. C), 122.7
Colorless crystals, 89 % yield, m.p. 177–178 °C (from benzene); 1H
2
NMR (400 MHz, CDCl3): δ 2.75 (d, 1HA, JHH =16 Hz, CH2), 2.8 (d,
2
1HB, JHH =16 Hz, CH2), 4.57 (s, 1H, H-8), 4.89 (s, 1H, H-1), 7.07 (s,
arom. H-3), 7.22 (m, 2H, arom. H-5,6), 7.34 (m, 2H, H-11,12), 11.43
(br. s, 1H, OH). 13C NMR (125.71 MHz, CDCl3): δ 171.8 (s, C = O),
157.6 (s, C-12(11), CH=), 140.95 (qq, 2JCF =35.4 Hz, 3JCF =3.5 Hz, C-
1
(s, arom. C), 122.0 (q, JCF =273.4 Hz, 2CF3), 52.2 (s, CH3O), 49.3 (s,
C-8(1)), 46.0 (s, C-8(1)), 38.1 (s, CH2). 19F NMR (376.49 MHz, CDCl3):
6

M.M. Kremlev, et al.
JournalofFluorineChemistry232(2020)109450
10(9), CF3C=), 139.9 (s, arom. C-7(2)), 136.8 (qq, 2JCF =35.4 Hz, 3JCF
143.4 (qq, JCF =35 Hz, JCF =3.8 Hz, C-9(10), CF3C=), 142.7 (s,
arom. C-2(7)), 139.0 (s, C-12(11), CH=), 138.4 (s, C-11(12), CH=),
127.2 (s, arom. C), 126.4 (s, arom. C), 124.7 (s, arom. C), 122.4 (s,
arom. C), 121.5 (q, 1JCF =271.6 Hz, 2CF3), 48.8 (s, C-8(1)), 45.5 (s, C-
1(8)), 37.5 (s, CH2). 19F NMR (376.49 MHz, CDCl3): δ -61.70 (q, 3 F,
2
3
=3.5 Hz, C-9(10), CF3C=), 136.7 (s, arom. C-2(7)), 127.7 (s, arom. C),
1
1
127.4 (s, arom. C), 121.2 (q, JCF =272.3 Hz, CF3), 121.0 (q, JCF
=272.3 Hz, CF3), 115.2 (s, C-12(11), CH=), 52.12 (s, C-8(1)), 41.9 (s,
C-1(8)), 35.1 (s, CH2). 19F NMR (376.49 MHz, CDCl3) δ -60.89 (q, 3 F,
3JFF =11.2 Hz, CF3), -61.88 (q, 3 F, JFF =11.2 Hz, CF3). Analysis:
3JFF =11.2 Hz, CF3), -62.27 (q, 3 F, JFF =11.2 Hz, CF3). Analysis:
3
3
Found: %C 55.23; %H 2.99. C16H10F6O2. Calcd.: %C 55.18; %H 2.89.
Found: %C 55.14; %H 3.00. C16H10F6O2. Calcd.: %C 55.18; %H 2.89.
4.21. [9,10-Bis(trifluoromethyl)tricyclo(6.2.2.02,7)dodeca-2,4,6,9,11-
pentaen-4-yl] carboxylic acid (11c)
4.25. [10-(Methoxy)-11,12-bis(trifluoromethyl)tricyclo(6.2.2.02,7
dodeca-2,4,6,11-butaen-9-yl] carboxylic acid (14)
)
Colorless crystals, 91 % yield, m.p. 189−190 °C (from benzene); 1H
NMR (400 MHz, CDCl3) δ 5.35 (m, 2H, H-8(1)), 7.1 (m, 2H, H-12(11)),
7.4(d, 1H, 3JHH =7.6 Hz, arom. H-6), 7.9 (d, 1H, 3JHH =7.6 Hz, arom.,
H-5), 8.0 (s, arom. H-6). 13C NMR (125.71 MHz, CDCl3): δ 167.4 (s, C =
O), 149.1 (s, C-7(2)), 144.9 (s, C-2(7)), 144.5 (m, 2C, C-10(9),
2CF3C=), 140.0 (s, C-12(11), CH=), 139.4 (s, C-11(12), CH=), 128.0
(s, arom. C), 127.5 (s, arom. C), 124.4 (s, arom. C), 123.9 (s, arom. C),
Colorless crystals, 89 % yield, m.p. 137−138 °C (from hexane); 1H
NMR (400 MHz, CDCl3): δ 2.66 (s, 1H, H−9), 3.43 (s, 3H, OCH3),): 3.88
(s, 1H, H-10), 4.59 (s, 1H, H-8), 4.67 (s, 1H, H-1), 7.28 (m, 4H, arom.
H). 13C NMR (125.71 MHz, CDCl3): δ 176.7 (s, C = O), 139.4 (qq, 2JCF
=32.4 Hz, 3JCF =3.5 Hz, C-12(11), CF3C=), 138.2 (qq, 2JCF =32.4 Hz,
3JCF =3.5 Hz, C-11(12), CF3C=), 137.3 (s, arom. C-7(2)), 136.8 (s,
arom. C-2(7)), 127.4 (s, 2C, arom. C), 125.4 (s, arom. C), 124.9 (s,
1
1
122.2 (q, JCF =272.3 Hz, 2CF3), 48.7 (s, C-8(1)), 48.6 (s, C-1(8)). 19F
arom. C), 121.3 (q, JCF =273.3 Hz, 2CF3), 81.6 (s, C-10), 57.2 (s,
NMR (376.49 MHz, CDCl3): δ -62.22 (br. s, 2CF3). Analysis: Found: %C
OCH3), 51.6 (s, C-9), 45.6 (s, C-8(1)), 42.5 (s, C-1(8)). 19F NMR (376.49
MHz, CDCl3): δ -61.13 (q, 3 F, 3JFF =11.2 Hz, CF3), -62.24 (q, 3 F, 3JFF
=11.2 Hz, CF3). Analysis: Found: %C 52.74; %H 3.42. C16H11F6O3.
Calcd.: %C 52.60; % H 3.01.
53.99; %H 2.62. C15H8F6O2. Calcd.: %C 53.91; %H 3.41.
4.22. [9,10-Bis(trifluoromethyl)tricyclo(6.2.2.02,7)dodeca-2,4,6,9,11-
pentaen-1-yl] acetic acid (12c)
4.26. [11,12-Bis(trifluoromethyl)tricyclo(6.2.2.02,7)dodeca-2,4,6,9,11-
pentaen-9-yl] carboxylic acid (15)
Colorless crystals, 89 % yield m.p. 169−170 °C (from benzene); 1
H
2
NMR (400 MHz, CDCl3): δ 3.67 (d, 1HA, JHH =18 Hz, CH2), 3.83 (d,
1HB, 2JHH =18 Hz, CH2), 5.23 (d, 1H, 3JHH =5.6 Hz, H-8), 7.47 (m, 4H,
Colorless crystals, 88 % yield, m.p. 187−188 °C (from benzene); 1H
NMR (400 MHz, DMSO-d6): δ 5.36 (d, 1H, 3JHH = 5.6 Hz, H-1), 5.72 (s,
1H, H-8), 7.08 (s, 2H, arom. H-3,6), 7.39 (m, 2H, arom. H-4,5), 7.94 (d,
3
3
arom. H-3,4,5,6), 7.26 (d, 1H, JHH =6.4 Hz, H-11), 7.34 (d, 1H, JHH
=6.4 Hz H-12), 10.87 (br. s, 1H, OH). 13C NMR (125.71 MHz, DMSO-
2
3
3
D6): δ 172.5 (s, C = O), 147.2 (qq, JCF =34.5 Hz, JCF =4.4 Hz, C-
1H, JHH =5.6 Hz, H-10). 13C NMR (125.71 MHz, DMSO-d6): δ 169.0
2
3
10(9), CF3C=), 145.7 (qq, JCF =34.5 Hz, JCF =4.4 Hz, C-9(10),
CF3C=), 145.7 (s, arom. C-7(2)), 145.5 (s, arom. C), 144.9 (s, C-12(11),
CH=), 137.1 (s, C-11(12), CH=), 125.2 (s, arom. 2C), 124.0 (s, arom.
(s, C = O), 148.8 (s, C-10(9), CH=), 145.2 (s, C-9(10), CH=), 145.06
(m, 2C, C-11,12, 2CF3C=), 144.8 (s, arom. C), 143.4 (s, arom. C-7(2)),
142.8 (s, arom. C-2(7)), 126.0 (s, arom. C), 124.8 (s, arom. C), 124.5 (s,
arom. C), 122.1 (q, 1JCF =271.3 Hz, 2CF3), 49.3 (s, C-8(1)), 48.8 (s, C-
1
1
C), 122.9 (q, JCF =274.6 Hz, CF3), 122.6 (q, JCF =274.6 Hz, CF3),
122.3 (s, arom. C), 54.5 (s, C-8(1)), 48.2 (s, C-1(8)), 34.7 (s, CH2). 19F
1(8)). 19F NMR (376.49 MHz, DMSO-d6): δ -62.22 (q, 3 F, JFF =11.2
3
3
3
NMR (376.49 MHz, CDCl3): δ -57.31 (q, 3 F, JFF =11.3 Hz, CF3),
Hz, CF3), -62.35 (q, 3 F, JFF =11.2 Hz, CF3). Analysis: Found: %C
3
-60.22 (q, 3 F, JFF =11.3 Hz, CF3). Analysis: Found: %C 55.11; %H
53.90; %H 2.68. C15H8F6O2. Calcd.: %C 53.91; % H 2.41.
3.00. C16H10F6O2. Calcd.: %C 55.18; %H 2.89.
Declaration of competing interest and authorship conformation
form
4.23. [9,10-Bis(trifluoromethyl)tricyclo(6.2.2.02,7)dodeca-2,4,6,9,11-
pentaen-1-yl] carboxylic acid (12d)
Please check the following as appropriate:
Colorless crystals, 92 % yield, m.p. 203−205 °C (from benzene); 1H
3
NMR (400 MHz, DMSO-D6): δ 5.62 (d, 1H, JHH = 5.2 Hz, H-8), 6.72
All authors have participated in (a) conception and design, or ana-
•
(d, 1H, 3JHH = 5.2 Hz, H-11), 7.16 (m, 2H, arom. H-4,5), 7.23 (m, 1H,
lysis and interpretation of the data; (b) drafting the article or re-
vising it critically for important intellectual content; and (c) ap-
proval of the final version.
3
3
H-12), 7.57 (d, 1H, JHH =8 Hz, arom. H-6), 7.67 (d, 1H, JHH = 7.2
Hz, arom. H-3). 13C NMR (125.71 MHz, CDCl3): δ 167.9 (s, C = O),
146.2 (s, arom. C-7(2)), 145.5 (s, arom. C-2(7)), 144.6 (m, 2C, C-9,10,
CF3C=), 140.7 (s, C-12(11), CH=), 139.4 (s, C-11(12), CH=), 127.6 (s,
arom. C), 127.0 (s, arom. C), 126.7 (s, arom. C), 125.4 (s, arom. C),
This manuscript has not been submitted to, nor is under review at,
•
another journal or other publishing venue.
The authors have no affiliation with any organization with a direct
•
122.2 (q, JCF =273.1 Hz, 2CF3), 48.8 (s, C-8(1)), 45.8 (s, C-1(8)). 19F
or indirect financial interest in the subject matter discussed in the
manuscript
1
3
NMR (376.49 MHz, CDCl3): δ -61.92 (q, 3 F, JFF =11.2 Hz, CF3),
3
-62.04 (q, 3 F, JFF =11.2 Hz, CF3). Analysis: Found: %C 53.88; %H
The following authors have affiliations with organizations with di-
•
2.52. C15H8F6O2. Calcd.: %C 53.91; %H 2.41.
rect or indirect financial interest in the subject matter discussed in
the manuscript:
4.24. [9,10-Bis(trifluoromethyl)tricyclo(6.2.2.02,7)dodeca-2,4,6,9,11-
pentaen-3-yl] acetic acid (13)
Acknowledgement
Colorless crystals, 91 % yield, m.p. 130−131 °C (from benzene); 1H
We thank Dr. I.I. Gerus for help with the interpretation of NMR-
spectra.
2
NMR (400 MHz, CDCl3): δ 3.73 (d, 1HA, JHH =16 Hz, CH2), 3.83 (d,
1HB, 2JHH =16 Hz, CH2), 5.24 (d, 1H 3JHH = 5.2 Hz, H-8), 5.46 (d, 1H,
3
3JHH = 5.2 Hz, H-1), 6.92 (d, 1H, JHH = 7.2 Hz, H-11), 7.00 (m, 3H,
Appendix A. Supplementary data
3
arom. H-4,5,6), 7.26 (d, 1H, JHH = 7.2 Hz, H-12), 11.02 (br. s, 1H,
OH). 13C NMR (125.71 MHz, CDCl3): δ 177.1 (s, C = O), 143.2 (qq, 2JCF
Supplementary material related to this article can be found, in the
online version, at doi:https://doi.org/10.1016/j.jfluchem.2020.109450.
3
=35 Hz, JCF =3.8 Hz, C-10(9), CF3C=), 144.1 (s, arom. C-7(2)),
7

M.M. Kremlev, et al.
JournalofFluorineChemistry232(2020)109450
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