Routes from 1,1-cycloalkanedicarboxylic acids to geminal bis(polyfluoromethyl) substituted carbocycles

Article abstract of DOI:10.1016/S0022-1139(01)00353-0

1-Fluoroformyl-1-(trifluoromethyl)cycloalkanes (1), prepared by treatment of 1,1-cycloalkane-dicarboxylic acids with SF₄, were efficiently reduced to 1-hydroxymethyl-1-(trifluoromethyl)-cycloalkanes (2). Routes for the conversion of alcohols 2

Full text of DOI:10.1016/S0022-1139(01)00353-0

Journal of Fluorine Chemistry 109 ꢀ2001) 95±102
Routes from 1,1-cycloalkanedicarboxylic acids to geminal
bisꢀpoly¯uoromethyl) substituted carbocycles
Adam Wolniewicz, Wojciech Dmowski*
Institute of Organic Chemistry, Polish Academy of Sciences, 01-224 Warsaw, Poland
Received 2 November 2000; accepted 20 December 2000
Abstract
1-Fluoroformyl-1-ꢀtri¯uoromethyl)cycloalkanes ꢀ1), prepared by treatment of 1,1-cycloalkane-dicarboxylic acids with SF4, were
ef®ciently reduced to 1-hydroxymethyl-1-ꢀtri¯uoromethyl)-cycloalkanes ꢀ2). Routes for the conversion of alcohols 2 to 1-methyl-1-
ꢀtri¯uoromethyl)cycloalkanes ꢀ4), 1-¯uoromethyl-1-ꢀtri¯uoromethyl)cycloalkanes ꢀ6) and 1-di¯uoromethyl-1-ꢀtri¯uoromethyl)cycloalk-
anes ꢀ8), via iodides 3, tri¯ates 5 and aldehydes 7, respectively, were investigated. # 2001 Elsevier Science B.V. All rights reserved.
Keywords: 1-Fluoroformyl-1-ꢀtri¯uoromethyl)cycloalkanes; Bisꢀpolytri¯uoromethyl)cycloalkanes; 1-Hydroxymethyl-1-ꢀtri¯uoromethyl)cycloalkanes;
1-Formyl-1-ꢀtri¯uoromethyl)cycloalkanes
1. Introduction
ꢀtri¯uoromethyl)cycloalkanes ꢀ2) by reduction of the COF
groups with LiAlH4. The reductions proceeded readily in
Et2O solutions at 5±88C affording alcohols 2 in high yields
and of 97±99% purity.
1,1-Dimethylcycloalkanes are common fragments of ter-
penes and their derivatives such as retenoids, Vitamin D and
pyrethroids. The search for convenient methods leading to
carbocycles bearing CF3, CHF2 and CH2F groups instead of
one or two CH3 groups on a quarternary carbon atom is of
considerable interest for the preparation of ¯uorinated ana-
logues of natural compounds. Our approach to the problem
has been based on ¯uorination of geminal carboxylic groups
with sulphur tetra¯uoride. In the preceding paper [1] we
described highly selective transformations of six-, ®ve-,
four- and three-membered 1,1-cycloalkanedicarboxylic
acids to either bisꢀtri¯uoromethyl)cycloalkanes or to
1-¯uoroformyl-1-ꢀtri¯uoromethyl)cycloalkanes. The pre-
sent paper deals with transformations of the COF groups
in the latter compounds into CHF2, CH2F and CH3 groups
to give a variety of bisꢀpoly¯uoromethyl)substituted
carbocycles.
Conversion of the CH2OH group in 2 into the CH3 group
to form compounds 4a±c created, however, some problems.
Usually, hydroxymethyl groups are readily converted into
methyl groups via iodides, mesylates or tosylates. In our
case, however, treatment of mesylate, prepared from alcohol
2a, with LiAlH4 resulted in cleavage of the oxygen±sulphur
bond which lead to almost quantitative recovery of 2a; this
was probably due to the electron withdrawing effect of the
CF3 group and thus reduced leaving groups abilities. The
attempted iodination of alcohols 2 by conventional methods
ꢀ48% hydroiodic acid, NaI in phosphoric acid) also failed.
The above mentioned adversities are understood by con-
sidering steric hindrances to a nucleophilic attack on the
carbon atom of the CH2OH group and to the formation of
pyramidal intermediate carbanions. The steric environment
of the attacked carbon atom in alcohols 2 resembles that in
neopentyl derivatives which are known to be extremely
inert; for example, it has been found that the reaction of
neopentyl alcohol with iodine and phosphorus gives only a
4±9% yield of neopentyl iodide [2]. Moreover, compounds
2a±d are undoubtedly even more crowded than neopentyl
alcohol due to the presence of a bulky CF3 group. Alcohols
2a±c were successfully converted into the respective iodides
3a±c in a 50±70% yields by using methylꢀtriphenoxy)pho-
sphonium iodide, formed in situ from triphenyl phosphite
2. Results and discussion
The reaction pathways are shown in Scheme 1.
In the ®rst step, 1-¯uoroformyl-1-ꢀtri¯uoromethyl)cy-
cloalkanes ꢀ1) were transformed into 1-hydroxymethyl-1-
* Corresponding author. Fax: ‡48-22-632-6681.
E-mail address: dmowski@icho.edu.pl ꢀW. Dmowski).
0022-1139/01/$ ± see front matter # 2001 Elsevier Science B.V. All rights reserved.
PII: S 0 0 2 2 - 1 1 3 9 ꢀ 0 1 ) 0 0 3 5 3 - 0

96
A. Wolniewicz, W. Dmowski / Journal of Fluorine Chemistry 109 ,2001) 95±102
Scheme 1.
and methyl iodide, as a iodinating agent Ð the best proce-
dure for iodination of sterically hindered alcohols [3,4].
Iodides 3a±c were readily reduced to 1-methyl-1-ꢀtri¯uor-
omethyl)cycloalkanes 4a±c ꢀ50±80% yield) by treatment
with tri-n-butyltin hydride in the presence of catalytic
amount of AIBN, according to the literature procedure [5].
The attempted direct conversion of CH2OH groups
in alcohols 2 into CH2F groups by treatment with SF4 [6]
or Et2NCF3 [7] failed. In both cases only trace amounts
of 1-¯uoromethyl-1-ꢀtri¯uoromethyl)cycloalkanes 6 were
detected by GLC±MS analyses; in the latter case the respec-
tive 1-ꢀtri¯uoromethyl)-1-cycloalkyl formamides were main
products. The most widely used method for the conversion
of hydroxy compounds to ¯uoroderivatives is cleavage of
esters of methanesulphonic, p-toluenesulphonic and espe-
cially tri¯uoromethanesulphonic acids with tetraalkylam-
monium ¯uorides [8]. Mesylates and tosylates of alcohols 2
were, however, not suf®ciently reactive, but good results
were obtained when tri¯ates 5a±c were treated with tetra-n-
butylammonium ¯uoride; the reactions proceeded in diethyl
ether at ambient temperature to give 1-¯uoromethyl-1-ꢀtri-
¯uoromethyl)cycloalkanes 6a±c.
Interesting relationships between the number of ¯uorine
atoms in the methyl groups and boiling points of gem-
dimethylcycloalkanes has been observed ꢀTable 1). Substi-
tution of one of the CH3 groups with a CF3 group increases
the boiling points of the respective cyclohexane and cyclo-
pentane by only a few degrees while boiling points of
smaller ring cycloalkanes rise by ca.12±188C. Further ¯uor-
ination ꢀof the second CH3 group) practically does not affect
boiling points of cyclopentanes but in other cases the highest
boiling points are observed for CF3±CH2F and CF3±CHF2
substituted cycloalkanes while bisꢀtri¯uoromethyl)cycloalk-
anes boil at the same temperature as their CF3±CH3 analo-
gues. Some errors in determination of boiling points ꢀby
distillation) could not be excluded.
In conclusion, preceding [1] and the present results have
shown that geminal cycloalkanedicarboxylic acids can be
converted into corresponding gem-dimethylcycloalkanes
with variable number of ¯uorine atoms in the methyl groups
by selective ¯uorination of the former with SF4 in the ®rst
step and by using known procedures in the next reaction
steps. These results pave the way for the preparation of a
variety of ¯uoromethyl analogues of naturally occurring
compounds possessing geminal methyl groups.
In the aim to convert CH2OH groups into CHF2 groups,
alcohols 2a±c were ®rst oxidised to aldehydes 7a±c using a
CrO3±pyridine reagent [9,10]. Treatment of these aldehydes
7a and 8b with sulphur tetra¯uoride under mild conditions
ꢀgeneral method for the preparation of di¯uoromethyl deri-
vatives [6]) afforded 1-di¯uoromethyl-1-ꢀtri¯uoromethyl)-
cycloalkanes 8a and 8b.
3. Experimental
Melting points were determined in capillaries and
boiling points were measured during distillation; both are

A. Wolniewicz, W. Dmowski / Journal of Fluorine Chemistry 109 ,2001) 95±102
97
Table 1
Boiling points ꢀ8C) of 1,1-dimethylcycloalkanes and 1,1-bisꢀpolyfluoromethyl)cycloalkanes
Compound ꢀR1±R2)
CH3±CH3
CF3±CH3
CF3±CH2F
CF3±CHF2
136±138
CF3±CF3
124±126d
119.6a
124±126
147±148
87.5a
53.2b
20.6a
90±91
65±66
37±38c
91±92
76±78
91±92
90±92d
66±68d
44±46d
a Ref. [11].
b Ref. [12].
c Ref. [13].
d Ref. [1].
uncorrected. H, 13C and 19F NMR spectra were recorded
with a Varian Gemini 200 spectrometer at 200, 50 and
188 MHz, respectively. Chemical shifts are quoted in ppm
from internal TMS for 1H and 13C ꢀpositive down®eld) and
from internal CFCl3 ꢀpositive up®eld). Crude mixtures of
products were analysed with a Shimadzu GC-14A Chroma-
tograph using a 3:5 m  2 mm column packed with 5%
silicone oil SE-52 on Chromosorb G. GC±MS analyses
were performed with a Hewlett-Packard 5890 apparatus
using a 30 m capillary column coated with a HP-5 oil. Mass
spectra of pure compounds were obtained with an AMD-604
spectrometer and IR spectra with a Perkin-Elmer Spectrum
2000 instrument.
44.2 ppm ꢀq, JCF ˆ 21:4 Hz, C-1); 25.1 ppm ꢀm, C-2 and
C-3); 20.7 ppm ꢀs, C-4). 19F NMR ꢀin CDCl3) d: 76.4 ppm
ꢀs, CF3). MS ꢀEI, 70 eV) m/z ꢀrelative intensity, ion): 164
1
2
‡
‡
[24, ꢀM À H2O) ]; 149 [15, ꢀM À CH2OH À 2H) ]; 132
‡
[100, ꢀM À CH2OH À F) ]; 95 [25, ꢀM À CO À 2HF
‡
‡
‡
ÀF) ]; 81 ꢀ13, C6H9 ); 68 ꢀ13, C5H8 ).
3.1.2. 1-Hydroxymethyl-1-,trifluoromethyl)cyclopentane
,2b)
Yield: 81%. Bp: 158±1608C. GLC purity: >99%. Analy-
sis: found: C, 50.0; H, 6.8; F, 34.0%. Calculated for
C7H11F3O ꢀ168.16): C, 50.0; H, 6.6; F, 3.9%. 1H NMR
ꢀin CDCl3) d: 1.60±1.92 ppm ꢀm, 9H); 3.62 ppm ꢀd,
J ˆ 0:7 Hz , CH). 13C NMR ꢀin CDCl3): 129.6 ppm ꢀq,
2
3
3.1. 1-Hydroxymethyl-1-,trifluoromethyl)cycloalkanes
,2a±d)
1JCF ˆ 279:7 Hz , CF); 64 ppm ꢀq, JCF ˆ 2:6 Hz , CH);
3
2
52.7 ppm ꢀq, 2JCF ˆ 22:6 Hz, C-1); 29.7 ppm ꢀq,
3JCF ˆ 1:8 Hz, C-2); 26.0 ꢀs, C-3). 19F NMR ꢀin CDCl3)
‡
A solution of acid ¯uorides 1a±d [1] ꢀ40 mmol) in dry
ether ꢀ50 ml) was added dropwise, while stirring, to a
suspension of LiAlH4 ꢀ1.7 g, 45 mmol) in ether ꢀ150 ml)
precooled to 58C in such a rate to keep the temperature at 5±
88C. After addition, the reaction mixture was stirred at 58C
for 2 h then quenched by a slow addition of 2% hydrochloric
acid ꢀ200 ml) and the stirring was continued until the
inorganic salt dissolved completely. The organic layer
was separated dried over MgSO4, ether was removed on a
rotary evaporator and the residue was distilled under atmo-
spheric pressure.
d: 73.6 ppm ꢀs, CF3). MS: 167 [0.4, [M À H) ]; 150 [2,
‡
‡
ꢀM À H2O) ]; 149 [3, ꢀM À F) ]; 135 ꢀ19); 122 [10,
‡
‡
ꢀM À C2H4 À H2O) ]; 118 [100, ꢀM À CH2OH À F) ];
‡
‡
81 [17, ꢀM À H2O À CF3) ]; 77 [22, ꢀC3H3F2) ]; 69 ꢀ3,
‡
‡
‡
‡
CF3 ); 67 ꢀ41, C5H7 ); 54 ꢀ13, C4H6 ); 41 ꢀ15, C3H5 ).
3.1.3. 1-Hydroxymethyl-1-,trifluoromethyl)cyclobutane
,2c)
Yield: 75%. Bp: 140±1418C. GLC purity: >96%. Analy-
sis: found: C, 45.5; H, 6.1; F, 37.0%. Calculated for
1
C6H9F3O ꢀ154.13): C, 46.8; H, 5.9; F, 37.0%. H NMR
ꢀin CDCl3) d: 1.66 ppm ꢀs, OH); 1.90±2.10 ppm ꢀm, 4H);
3.1.1. 1-Hydroxymethyl-1-,trifluoromethyl)
cyclohexane ,2a)
Yield: 86% ꢀbased on 1a). Bp: 184±1868C. GLC purity:
>98%. Analysis: found: C, 52.5; H, 7.4; F, 31.4%. Calcu-
lated for C8H13F3O ꢀ182.19): C, 52.7; H, 7.2; F, 31.3%. 1H
2.16±2.35 ppm ꢀm, 2H); 3.82 ꢀs, CH2). 13C NMR ꢀin
1
CDCl3): 128.2 ppm ꢀq, JCF ˆ 279:6 Hz , CF); 63.6 ppm
3
3
2
ꢀq, JCF ˆ 2:5 Hz , CH); 46.2 ppm ꢀq, JCF ˆ 25:6 Hz , C-
2
3
1); 22.9 ppm ꢀq, JCF ˆ 2:9 Hz, C-2); 14.75 ppm ꢀs, C-3).
19F NMR ꢀin CDCl3) d: 76.7 ppm ꢀs, CF3). MS: 136 [18,
‡
‡
‡
NMR ꢀin CDCl3) d: 1.15±1.80 ppm ꢀm, 11H); 3.79 ppm ꢀm,
ꢀM À H2O) ]; 134 [2, [M À HF) ]; 125 [26, ꢀM À C2H5) ];
‡ ‡
CH2). 13C NMR ꢀin CDCl3): 129.4 ppm ꢀq, JCF
ˆ
106 [14, ꢀM À CO À HF) ]; 105 [44, ꢀM À CHOH À F) ];
1
‡
3
284:0 Hz , CF); 61.3 ppm ꢀq, JCF ˆ 1:9 Hz , CH);
104 [99, ꢀM À CH2OH À F) ]; 103 ꢀ16); 85 [14,
3
2

98
A. Wolniewicz, W. Dmowski / Journal of Fluorine Chemistry 109 ,2001) 95±102
‡
‡
‡
ꢀM À CF3) ]; 78 [18, ꢀC3H4F2) ]; 77 [47, ꢀC3H3F2) ]; 69
3.2.2. 1-Iodomethyl-1-,trifluoromethyl)cyclopentane ,3b)
Yield: 51%. ꢀ2.5 g, 9.1 mmol). Bp: 58±598C/11±12 Torr;
828C/25 Torr. GLC purity: >99%. Analysis: found: C, 30.5;
H, 3.5; F, 20.7; I, 45.6%. Calculated for C7H10F3I ꢀ278.08):
C, 30.4; H, 3.6; F, 20.5; I, 45.6%. H NMR ꢀin CDCl3): d:
1.85±1.63 ppm ꢀm, 4H); 2.10±1.90 ppm ꢀm, 4H); 3.37 ppm
ꢀs, 2H). 13C NMR ꢀin CDCl3): d: 127.3 ppm ꢀq,
‡
‡
‡
ꢀ5, CF3 ); 67 ꢀ100, C5H7 ); 57 ꢀ66, C3H5O ); 55 ꢀ9,
C4H7 ); 53 ꢀ11, C4H5 ); 51 ꢀ9, C4H3 ); 42 ꢀ11, C3H6 );
41 ꢀ23, C3H5 ).
‡
‡
‡
‡
‡
1
3.1.4. 1-Hydroxymethyl-1-,trifluoromethyl)cyclopropane
,2d)
Yield: 73%. Bp: 126±1288C. GLC purity: >97%. Analy-
sis: found: C, 42.7; H, 5.1; F, 40.4%. Calculated for
2
1JCF ˆ 282:5 Hz , CF); 51.1 ppm ꢀq, JCF ˆ 23:9 Hz , C-
3
1); 34.1 ppm ꢀs, C-2); 26.4 ppm ꢀs, C-3); 10.6 ppm ꢀs, CH2I).
19F NMR ꢀin CDCl3): d: 74.6 ppm ꢀs, CF3). MS: 278 ꢀ6,
1
C5H7F3O ꢀ140.11): C, 42.9; H, 5.0; F, 40.7%. H NMR
ꢀin CDCl3) d: 0.73±0.83 ppm ꢀm, 2H); 1.00±1.07 ppm ꢀm,
‡
‡
‡
M
ꢀ); 152 [7, ꢀM À I ‡ H) ]; 151 [100, ꢀM À I) ]; 132 [5,
‡
‡
2H); 1.89 ꢀs, OH); 3.73 ppm ꢀs, CH2); 13C NMR ꢀin CDCl3):
ꢀM À I À F) ]; 131 [58, ꢀM À I À HF) ]; 123 [7,
‡ ‡
1
127.0 ppm ꢀq, JCF ˆ 273:7 Hz , CF); 63.4 ppm ꢀs, CH2);
ꢀM À I À C2H4) ]; 111 [46, ꢀM À I À 2HF) ]; 103 [8,
‡ ‡
3
2
3
24.9 ppm ꢀq, JCF ˆ 31:5 Hz, C-1); 7.1 ppm ꢀq, JCF
ˆ
ꢀM À I À C2H4 À HF) ]; 77 [47, ꢀC3H3F2) ]; 69 ꢀ4,
‡ ‡ ‡
2:7 Hz, C-2). 19F NMR ꢀin CDCl3) d: 69.7 ppm ꢀs, CF3).
CF3 ); 53 ꢀ7, C4H5 ); 41 ꢀ45, C3H5 ).
‡
‡
‡
MS: 140 ꢀ1, M ꢀ); 139 [1, ꢀM À H) ]; 138 [1, ꢀM À 2H) ];
‡
‡
125 [7, ꢀM À CH3) ]; 123 [4, ꢀM À OH) ]; 122 [7, ꢀM
3.2.3. 1-Iodomethyl-1-,trifluoromethyl)cyclobutane ,3c)
Yield: 57% ꢀ2.9 g, 11.0 mmol). Bp: 36±388C/12 Torr.
GLC purity: >99%. Analysis: found: C, 27.2; H, 3.1; F,
21.6; I, 48.0%. Calculated for C6H8F3I ꢀ164.02): C, 27.3; H,
3.1; F, 21.6; I, 48.1%. 1H NMR ꢀin CDCl3): d: 2.18±1.85 ppm
ꢀm, 2H); 2.46±2.29 ppm ꢀm, 4H); 3.44 ppm ꢀs, 2H). 13C
‡
‡
‡
ÀH2O) ]; 119 [5, ꢀM À H2F) ]; 112 [87, ꢀM À C2H4) ];
‡
‡
110 [5, ꢀM À CH2O) ]; 109 [4, ꢀM À CH2OH) ]; 105 [20,
‡
‡
ꢀM À CH3 À HF) ]; 103 ꢀ13); 92 [81, ꢀM À CO À HF) or
‡
‡
ꢀM À C2H4 À HF) ]; 91 [100, ꢀM À CO À H2F) ]; 90 [97,
‡
‡
ꢀM À CH2OH À F) ]; 77 [47, ꢀC3H3F2) ]; 71 [18,
‡
‡
‡
ꢀM À CF3) ]; 69 ꢀ17, CF3 ); 59 ꢀ10, C3H4F ); 57 ꢀ28,
NMR ꢀin CDCl3): d: 125.6 ppm ꢀq, 1JCF ˆ 280:4 Hz , CF);
3
‡
‡
‡
‡
2
C3H2F ); 56 ꢀ17, C4H8 ); 53 ꢀ31, C4H5 ); 41 ꢀ16, C3H5 ).
44.9 ppm ꢀq, JCF ˆ 27:0 Hz, C-1); 27.1 ppm ꢀs, C-2);
13.2 ppm ꢀs, C-3); 8.2 ppm ꢀs, CH2I). 19F NMR ꢀin CDCl3):
‡
‡
3.2. 1-Iodomethyl-1-,trifluoromethyl)cycloalkanes ,3a±c)
d: 77.4 ppm ꢀs, CF3). MS: 264 ꢀ10, M ꢀ); 137 [13, ꢀM À I) ];
‡
‡
118 [6, ꢀM À I À F) ]; 117 [100, ꢀM À I À HF) ]; 109 [21,
‡
‡
A mixture of alcohols 2a±c ꢀ22 mmol), methyl iodide
ꢀ4.7 g, 33 mmol) and triphenyl phosphite ꢀ7.4 g, 23.7 mmol)
were gently re¯uxed ꢀef®cient re¯ux condenser was
required to avoid a loss of MeI) for 24 h after which the
resultant dark-red slurry was subjected to distillation under
reduced pressure ꢀ50 Torr). The distillate, containing iodide
3 and phenol was dissolved in ether ꢀ100 ml) and the
solution was extracted with 0.25 N aqueous NaOH ꢀpre-
cooled to 0±58C; 2 Â 100 ml) followed by 10% aqueous
Na2SO3 ꢀ50 ml) and ®nally with water ꢀ50 ml). The organic
layer was separated, dried over anhydrous MgSO4 and the
solvent was removed on a rotary evaporator. The residue
was vacuum distilled to give iodides 3a±c as colourless
liquids.
ꢀM À I À C2H4) ]; 97 [69, ꢀM À I À 2HF) ]; 89 [25,
‡ ‡
ꢀM À I À C2H4 À HF) ]; 77 [47, ꢀC3H3F2) ]; 69 ꢀ5,
‡
‡
‡
‡
CF3 ); 53 ꢀ6, C4H5 ); 77 [47, ꢀC3H3F2) ]; 41 ꢀ15, C3H5 ).
3.3. 1-Methyl-1-,trifluoromethyl)cycloalkanes ,4a±c)
1-Iodo-1-ꢀtri¯uoromethyl)cycloalkanes3a±cꢀ12.4 mmol),
dry benzene ꢀ5 ml, distilled from sodium metal) and azoi-
sobutyronitrile ꢀAIBN, 15 mg) were placed in a 25 ml three-
necked bulb equipped with a thermometer, magnetic stirring
bar and a rubber septum. The bulb was purged with dry
argon then n-Bu3SnH ꢀ5.4 g, 18.6 mmol) was injected via
the septum. The reaction mixture was stirred at 608C for 3 h
after which products were distilled off under atmospheric
pressure through a 5 cm long Vigreux-type column to afford
compounds 4a±c as volatile liquids. Due to high volatility,
no C and H analyses were determined for compounds 4a±c.
3.2.1. 1-Iodomethyl-1-,trifluoromethyl)cyclohexane ,3a)
Yield: 67% ꢀ4.3 g, 14.7 mmol). Bp: 104±1068C/8 Torr.
GLC purity: >99%. Analysis: found: C, 32.7; H, 4.1; F, 19.5;
I, 43.4%. Calculated for C8H12F3I ꢀ292.08): C, 32.9; H, 4.1;
3.3.1. 1-Methyl-1-,trifluoromethyl)cyclohexane ,4a)
Yield: 80% ꢀ1.65 g; 9.9 mmol). Bp: 124±1268C. GLC
purity: >97%. Analysis: found: F, 34.3%. Calculated for
C8H13F3 ꢀ166.19): F, 34.3%. 1H NMR ꢀin CDCl3) d:
1
F, 19.5; I, 43.5%. H NMR ꢀin CDCl3): d: 1.46±1.20 ppm
ꢀm, 2H); 1.90±1.56 ppm ꢀm, 8H); 3.42 ppm ꢀs, 2H, CH2I).
13C NMR ꢀin CDCl3): d: 127.6 ppm ꢀq, JCF ˆ 284:2 Hz ,
1
CF3); 41.9 ppm ꢀq, 2JCF ˆ 23:4 Hz, C-1); 28.9 ppm ꢀs, C-2);
1.13 ppm ꢀs, CH3); 1.72±1.46 ppm ꢀm, 8H). 13C NMR ꢀin
24.7 ppm ꢀs, C-3); 20.5 ppm ꢀs, C-4); 4.9 ppm ꢀs, CH2). 19
F
CDCl3) d: 129.6 ppm ꢀq, JCF ˆ 282:1 Hz , CF); 40.1 ppm
1
3
‡
NMR ꢀin CDCl3): d: 76.9 ppm ꢀs, CF3). MS: 292 ꢀ17, M ꢀ);
ꢀq, 2JCF ˆ 24:7 Hz, C-1); 29.7 ppm ꢀs, C-2); 25.6 ppm ꢀs, C-
‡
‡
3
166 [8, ꢀM À I ‡ H) ]; 165 [100, ꢀM À I) ]; 146 [5,
3); 20.8 ppm ꢀs, C-4); 16.64 ppm ꢀq, JCF ˆ 2:3 Hz , CH).
3
‡
‡
ꢀM À I À F) ]; 145 [59, ꢀM À I À HF) ]; 125 [35, ꢀM À I
19F NMR ꢀin CDCl3) d: 81.3 ppm ꢀs, CF3). MS: 166 ꢀ1,
‡
‡
‡
‡
‡
‡
À2HF) ]; 123 ꢀ18); 117 [7, ꢀM À I À C2H4 À HF) ]; 55
M
ꢀ);Á151 [0.5, ꢀM À CH3) ]; 131 [2, ꢀM À CH3 À HF) ];
‡
‡
‡
‡
ꢀ55, C4H7 ); 43 ꢀ21, C3H7 ); 41 ꢀ41, C3H5 ).
123 [1, ꢀM À CH3 À C2H4) ]; 127 [2, ꢀM À HF2) ]; 111 [2,

A. Wolniewicz, W. Dmowski / Journal of Fluorine Chemistry 109 ,2001) 95±102
99
‡
‡
‡
ꢀM À CH3 À 2HF) ]; 97 [100, ꢀM À CF3) ]; 69 ꢀ5, CF3 );
36.3; S, 10.3%. Calculated for C9H12F6SO3 ꢀ314.22): C,
34.40; H, 3.85; F, 36.27; S, 10.20%. 1H NMR ꢀin CDCl3) d:
1.89±1.23 ppm ꢀm, 10H); 4.61 ppm ꢀs, CH2O). 13C NMR ꢀin
‡
‡
51 ꢀ7, C3H4F ); 41 ꢀ22, C3H5 ).
1
3.3.2. 1-Methyl-1-,trifluoromethyl)cyclopentane ,4b)
Yield: 65% ꢀ0.71 g; 4.6 mmol). Bp: 90±918C. GLC pur-
ity: >97%. Analysis: found: F, 37.2%. Calculated for
C7H11F3 ꢀ152.16): F, 37.0%. 1H NMR ꢀin CDCl3) d:
1.17 ppm ꢀs, 3H, CH3); 1.50±1.35 ppm ꢀm, 3H); 1.72±
1.63 ppm ꢀm, 3H); 2.01±1.85 ppm ꢀm, 2H). 13C NMR ꢀin
CDCl3) d: 127.5 ppm ꢀq, JCF ˆ 283 Hz, CF3); 118.6 ppm
ꢀq, 1JCF ˆ 319 Hz, SO2CF3); 73.2 ppm ꢀs, CH2O); 43.9 ppm
ꢀq, 2JCF ˆ 24:1 Hz, C-1); 25.0 ppm ꢀs, C-2); 24.6 ppm ꢀs, C-
3); 20.3 ppm ꢀs, C-4). 19F NMR ꢀin CDCl3) d: 77.2 ppm ꢀs,
‡
CF3); 75.0 ppmꢀs, SO2CF3). MS:165[6, ꢀM À OSO2CF3) ];
‡
‡
164[16, ꢀM À HOSO2CF3) ];149ꢀ32, CF3SO2O );145[18,
‡
CDCl3) d: 130.5 ppm ꢀq, 1JCF ˆ 280:1 Hz , CF); 47.4 ppm
ꢀM À OSO2CF3 À HF) ]; 136 [10, ꢀM À HOSO2CF3
3
‡
‡
ꢀq, 2JCF ˆ 24:7 Hz, C-1); 34.3 ppm ꢀs, C-2); 25.6 ppm ꢀs, C-
ÀC2H4) ]; 135 [13, ꢀM À HOSO2CF3 À C2H5) ]; 131 [20,
‡
3); 22.2 ppm ꢀq, 3JCF ˆ 2:8 Hz , CH). 19F NMR ꢀin CDCl3)
ꢀM À CH2OSO2CF3 À HF) ]; 123 [9, ꢀM À HOSO2CF3
3
‡
‡
‡
d: 77.5 ppm ꢀs, CF3). MS: 124 [1, ꢀM À C2H4) ]; 117 [2,
À2HF) ]; 122 [13, ꢀM À HOSO2CF3 À 2HF À H) ]; 111
‡ ‡
‡
‡
ꢀM À CH3 À HF) ]; 113 [8, ꢀM À HF2) ]; 109 [2,
[17, ꢀM À CH2OSO2CF3 À 2HF) ]; 95 ꢀ100, C1H3O3S );
‡ ‡
‡
‡
‡
ꢀM À CH3 À C2H4) ]; 105 [13, ꢀM À C2H4 À F) ); 97 [5,
69 ꢀ47, CF3 ); 55 ꢀ20, C4H5 ).
‡
ꢀM À CH3 À 2HF) ]; 91 [7, ꢀM À 2HF À F) ); 83 [100,
‡
‡
‡
ꢀM À CF3) ]; 77 [10, ꢀC3H3F2) ]; 69 ꢀ5, CF3 ); 55 ꢀ39,
3.4.2. 1-,Trifluoromethyl)-1-cyclopentylmethyl
trifluoromethylsulphonate ,5b)
‡
‡
‡
‡
C4H7 ); 53 ꢀ55, C4H5 ); 42 ꢀ64, C3H6 ); 41 ꢀ32, C3H5 ).
Yield: 84% ꢀ2.4 g; 8.1 mmol). Bp: 49±508C/2 Torr. GLC
purity: >99%. Analysis: found: C, 31.9; H, 3.4; F, 38.0; S,
10.4%. Calculated for C8H10F6SO3 ꢀ300.22): C, 32.0; H,
3.4; F, 38.0; S, 10.7%. 1H NMR ꢀin CDCl3) d: 1.85±1.55 ppm
ꢀm,6H);2.06±1.90ꢀm,2H);4.44 ppmꢀs,CH2O).13CNMRꢀin
3.3.3. 1-Methyl-1-,trifluoromethyl)cyclobutane ,4c)
Yield: 52% ꢀ0.8 g; 5.8 mmol). Bp: 65±668C. GLC purity:
>98%. Analysis: found: F, 38.1% ꢀan error caused by the
volatility of 4c). Calculated for C6H9F3 ꢀ138.04): F, 41.3%.
1H NMR ꢀin CDCl3) d: 1.33 ppm ꢀs, CH3); 2.05±1.67 ppm
CDCl3) d: 127.8 ppm ꢀq, 1JCF ˆ 281:1 Hz , CF); 118.6 ppm
3
ꢀm, 2H); 2.45±2.27 ppm ꢀm, 4H). 13C NMR ꢀin CDCl3):
ꢀq,1JCF ˆ 319:4 Hz ,SOCF3);75.7 ppmꢀs,CH2O);50.7 ppm
2
128.8 ppm ꢀq, 1JCF ˆ 278:3 Hz , CF); 41.5 ppm ꢀq, JCF
ˆ
2
3
ꢀq, 2JCF ˆ 25:3 Hz, C-1); 30.1 ppm ꢀs, C-2); 25 ppm ꢀs, C-3).
28:1 Hz,C-1);27.5 ppmꢀs,C-2);20.4 ppmꢀs,CH3);14.3 ppm
ꢀs, C-3). 19F NMR ꢀin CDCl3) d: 80.1 ppm ꢀs, CF3). MS: 138
19F NMR ꢀin CDCl3) d: 75.0 ppm ꢀs, CF3); 74.5 ꢀs, SO2CF3).
‡
‡
MS: 163 [1, ꢀCH2OSO2CF3) ]; 151 [6, ꢀM À OSO2CF3) ];
‡
‡
‡
ꢀ1.5,M ꢀ);123[2,ꢀM À CH3) ];110[48,ꢀM À C2H4) ];103
‡
‡
150 [4, ꢀM À HOSO2CF3) ]; 149 [3, ꢀOSO2CF3) ]; 135 [15,
‡
‡
[6, ꢀM À CH3 À HF) ]; 99 [3, ꢀM À HF2) ]; 95 [45,
‡
ꢀM À HOSO2CF3 À CH3) ]; 131 [26, ꢀM À OSO2CF3
‡
‡
ꢀM À CH3 À C2H4) ]; 91 [3, ꢀM À C2H4 À F) ]; 90 [18,
‡
‡
ÀHF) ]; 130 [18, ꢀM À HOSO2CF3 À HF) ]; 122 [8,
‡
‡
‡
ꢀM À C2H4 À HF) ]; 78 ꢀ16, C3H4F2 ); 77 ꢀ16, C3H3F2 );
‡
ꢀM À HOSO2CF3 À C2H4) ]; 117 [15, ꢀM À CH2OSO2-
‡
‡
‡
69 [100, CF3 or ꢀM À CF3) ]; 42 ꢀ33, C3H6 ); 41 ꢀ57,
‡
CF3 À HF) ]; 115 ꢀ12); 111 [17, ꢀM À OSO2CF3
‡
C3H5 ).
‡
‡
À2HF) ]; 109 [11, ꢀM À HOSO2CF3 À 2HF) ]; 97 [22,
‡
‡
ꢀM À CH2OSO2CF3 À 2HF) ]; 81 ꢀ100, HSO3 ); 69 ꢀ52,
3.4. 1-,Trifluoromethyl)-1-cycloalkylmethyl triflates ,5a±c)
‡
‡
‡
CF3 ); 42 ꢀ25, C3H6 ); 41 ꢀ40, C3H5 ).
Alcohols 2a±c ꢀ11 mmol), dry CH2Cl2 ꢀ20 ml) and pyr-
idine ꢀ1.5 g, 19 mmol) were placed in a 50 ml three-necked
bulb equipped with a thermometer, magnetic stirring bar and
a rubber septum. The bulb was purged with dry argon and
cooled to À158C then tri¯ic anhydride ꢀ4.0 g, 14.3 mmol)
was injected via the septum. The reaction mixture was
allowed to warm to ambient temperature and stirred for
3 h. After dilution with CH2Cl2 ꢀ100 ml), the solution was
washed with 1% hydrochloric acid ꢀ100 ml) precooled to
08C followed by iced water. The organic layer was sepa-
rated, dried over anhydrous MgSO4 and the solvent was
removed on a rotary evaporator at ambient temperature. The
residue was distilled under reduced pressure to give tri¯ates
5a±c as colourless oils.
3.4.3. 1-,Trifluoromethyl)-1-cyclobutylmethyl
trifluoromethylsulphonate ,5c)
Yield: 64% ꢀ2.4 g; 8.3 mmol). Bp: 78±808C/3 Torr. GLC
purity: >99%. Analysis: found: C, 29.7; H, 2.9; F, 40.0; S,
9.6%. Calculated for C7H8F6SO3 ꢀ286.22): C, 29.4; H, 2.8:
1
F, 39.8; S, 11.2%. H NMR ꢀin CDCl3) d: 2.17±1.98 ppm
ꢀm, 2H); 2.49±2.32 ppm ꢀm, 2H); 4.64 ppm ꢀs, CH2O). 13
C
1
NMR ꢀin CDCl3) d: 126.6 ppm ꢀq, JCF ˆ 279:2 Hz , CF);
3
1
118.7 ppm ꢀq, JCF ˆ 319:3 Hz , SOCF3); 75.1 ppm ꢀs,
2
2
CH2O); 44.8 ppm ꢀq, JCF ˆ 28:4 Hz, C-1); 23.0 ppm ꢀs,
C-2); 14.5 ppm ꢀs, C-3). 19F NMR ꢀin CDCl3) d: 77.5 ppm
‡
ꢀs, CF3); 75.0 ꢀs, SO2CF3). MS: 137 [2, ꢀM À OSO2CF3) ];
‡
136 [29, ꢀM À HOSO2CF3) ]; 117 [46, ꢀM À OSO2CF3
‡
‡
ÀHF) ]; 109 [23, ꢀM À OSO2CF3 À C2H4) ]; 103 [9,
‡
3.4.1. 1-,Trifluoromethyl)-1-cyclohexylmethyl
trifluoromethylsulphonate ,5a)
Yield: 85% ꢀ2.9 g; 9.3 mmol). Bp: 58±608C/1.5 Torr.
GLC purity: >99%. Analysis: found: C, 34.0; H, 3.9; F,
ꢀM À CH2OSO2CF3 À HF) ]; 97 [32, ꢀM À OSO2CF3
‡
‡
À2HF) ]; 77 [18, ꢀM À OSO2CF3 À 3HF) ]; 69 ꢀ53,
‡
‡
‡
CF3 ); 68 ꢀ5, [M À OSO2CF3 À CF3] ); 67 [100,
‡
ꢀM À HOSO2CF3 À CF3) ]; 41 ꢀ13, C3H5 ).

100
A. Wolniewicz, W. Dmowski / Journal of Fluorine Chemistry 109 ,2001) 95±102
3.5. 1-Fluoromethyl-1-,trifluoromethyl)cycloalkanes ,6a±c)
3.5.3. 1-Fluoromethyl-1-,trifluoromethyl)cyclobutane ,6c)
Yield: 54% ꢀ0.25 g; 1.6 mmol). Bp: 76±788C. GLC pur-
ity: >98%. Analysis: found: F, 41.1% ꢀan error caused by the
volatility of 8a). Calculated for C6H8F4 ꢀ142.08): F, 48.7%.
Solutions of tri¯ates 5a±c ꢀ6.7 mmol) in dry ether ꢀ5 ml)
were added dropwise to a suspension of commercial tetra-n-
butylammonium ¯uoride ꢀ2.3 g, 8.7 mmol) in dry ether
ꢀ20 ml) precooled to À158C and kept under an atmosphere
of argon. The reaction mixture was allowed to warm to
ambient temperature and stirred for 12 h, after which pro-
ducts were distilled off under atmospheric pressure and
redistilled through a 5 cm long Vigreux-type column to
afford compounds 6a±c as volatile liquids. Due to a high
volatility, no C and H analyses were determined for com-
pounds 6a±c.
1H NMR ꢀin CDCl3) d: 2.15±1.90 ppm ꢀm, 2H); 2.43±
2
2.18 ppm ꢀm, 4H); 4.53 ppm ꢀd, JHF ˆ 47:4 Hz , CHF).
2
13C NMR ꢀin CDCl3) d: 127.9 ppm ꢀq, JCF ˆ 279:2 Hz ,
1
CF3); 82.5 ppm ꢀd, 1JCF ˆ 175:6 Hz , CHF); 45.4 ppm ꢀdq,
2
2JCF ˆ 18:8 Hz , 2JCF ˆ 27:7 Hz, C-1); 22.3 ppm ꢀs, C-2);
14.6 ppm ꢀs, C-3). 19F NMR ꢀin CDCl3) d: 77.4 ꢀd,
4JHF ˆ 6:4 Hz , CF); 228.8 ppm ꢀtd, JHF ˆ 47:2 Hz ,
2
3
‡
4JHF ˆ 2:9 Hz , CHF). MS: 156 ꢀ2, M ꢀ); 141 [1,
2
‡
‡
‡
ꢀM À CH3) ]; 136 [7, ꢀM À HF) ]; 128 [6, ꢀM À C2H4) ];
‡
‡
123[27,ꢀM À CH2F) ];121[5,ꢀM À CH3 À HF) ];117[11,
‡
‡
3.5.1. 1-Fluoromethyl-1-,trifluoromethyl)cyclohexane ,6a)
Yield: 77% ꢀ0.95 g; 5.2 mmol). Bp: 147±1488C. GLC
purity: >99%. Analysis: found: F, 41.2%. Calculated for
C8H12F4 ꢀ184.15): F, 41.3%. 1H NMR ꢀin CDCl3) d: 1.80±
ꢀM À HF2) ]; 115 [6, ꢀM À 2HF À H) ]; 109 [20,
‡ ‡
ꢀM À C2H4 À F) ]; 108 [8, ꢀM À C2H4 À HF) ]; 103 [32,
‡
‡
ꢀM À CH2F À HF) ]; 97 [30, ꢀM À 2HF À F) ]; 90 ꢀ97); 89
‡
‡
ꢀ22); 87 [33, ꢀM À CF3) ]; 83 [21, ꢀM À CH2F À 2HF) ]; 77
‡
‡
1
1.20 ppm ꢀm, 10H); 4.54 ppm ꢀd, JHF ˆ 47:5 Hz, CH2F).
[79, ꢀM À CF3 À HF) ]; 69 ꢀ28, CF3 ); 67 [29,
‡ ‡
1
13C NMR ꢀin CDCl3) d: 128.4 ppm ꢀq, JCF ˆ 283:4 Hz ,
ꢀM À CF3 À HF) ]; 59 ꢀ88, [M À CF3 À C2H4] ); 57 ꢀ23,
‡ ‡ ‡
1
CF3); 80.9 ppm ꢀd, JCF ˆ 176:7 Hz , CHF); 44.25 ppm
C4H9 ); 55 ꢀ6, C4H7 ); 47 ꢀ100); 45 ꢀ13, C3H9 ); 43 ꢀ7,
C3H7 ); 42 ꢀ32, C3H6 ); 41 ꢀ45, C3H5 ); 40 ꢀ9, C3H4 ); 39
2
‡ ‡ ‡ ‡
ꢀdq, JCF ˆ 16:2 Hz , 2JCF ˆ 23:2 Hz, C-1); 24.6 ppm ꢀs,
2
‡
‡
C-2); 24.9 ppm ꢀs, C-3); 20.6 ppm ꢀs, C-4). 19F NMR ꢀin
ꢀ71, C3H3 ); 33 ꢀ22, CH2F ).
CDCl3) d: 77.2 ppm ꢀd, 4JHF ˆ 9:5 Hz , CF); 232.2 ppm ꢀt,
3
oct, JHF ˆ 47:5 Hz , 4JHF ˆ 4:8 Hz , CHF). MS: 184 ꢀ4,
2
2
3.6. 1-Formyl-1-,trifluoromethyl)cycloalkanes ,7a±c)
‡
‡
‡
‡
M
ꢀ); 151 [17, ꢀM À CH2F) ]; 145 [7, ꢀM À HF2) ]; 132
‡
[6, ꢀM À CH2F À F) ]; 131 [66, ꢀM À CH2F À HF) ]; 125
Methylene chloride ꢀ100 ml), pyridine ꢀ37.2 g, 0.47 mol)
and CrO3 ꢀ23.6 g, 0.24 mol) were stirred together for 1 h
until a deep-orange coloured slurry was formed. 1-Hydro-
xymethyl-1-ꢀtri¯uoromethyl)cycloalkane 2a±c ꢀ34 mol)
was added and the reaction mixture was stirred at ambient
temperature for 48 h, then ®ltered through a silica-gel
ꢀ10 cm) layer and the ®ltrate was washed with 10% hydro-
chloric acid ꢀ2 Â 100 ml) followed by water ꢀ100 ml). The
organic layer was dried over anhydrous MgSO4 and distilled
under vacuum or under atmospheric pressure of nitrogen.
Due to a high volatility, no C and H were determined for
compounds 7a±c.
‡
‡
[6, ꢀM À 2HF À F) ]; 115 [100, ꢀM À CF3) ]; 111 [37,
‡
ꢀM À CH2F À 2HF) ]; 109 [12, ꢀM À CH2F À C2H4
‡
‡
‡
ÀHF) ]; 95 [96, ꢀM À CF3 À HF) ]; 69 ꢀ6, CF3 ); 56
‡
‡
‡
ꢀ31, C4H8 ); 55 ꢀ28, C4H7 ); 42 ꢀ13, C3H6 ); 41 ꢀ74,
C3H5 ); 39 ꢀ37, C3H3 ); 33 ꢀ7, CH2F ).
‡
‡
‡
3.5.2. 1-Fluoromethyl-1-,trifluoromethyl)cyclopentane
,6b)
Yield: 66% ꢀ0.42 g; 2.29 mmol). Bp: 91±928C. GLC
purity: >96%. Analysis: found: F, 44.5%. Calculated for
C7H10F4 ꢀ170.15): F, 44.7%. 1H NMR ꢀin CDCl3) d: 1.95±
2
1.54 ppm ꢀm, 8H); 4.35 ppm ꢀd, JHF ˆ 47:5 Hz , CHF).
2
13C NMR ꢀin CDCl3) d: 128.5 ppm ꢀq, JCF ˆ 280:8 Hz ,
1
CF3); 83.4 ppm ꢀd, 1JCF ˆ 177:8 Hz , CHF); 52.3 ppm ꢀdq,
3.6.1. 1-Formyl-1-,trifluoromethyl)cyclohexane ,7a)
2
2JCF ˆ 16:9 Hz , 2JCF ˆ 24:2 Hz, C-1); 29.3 ppm ꢀs, C-2);
Yield: 72% ꢀ4.4 g; 24.5 mmol). Bp: 988C/33 mm Hg.
GLC purity: >98%. IR ꢀneat): d: 1739.0 cmÀ1 ꢀns, CHO).
Analysis: found: F, 31.6%. Calculated for C8H11F3O
ꢀ180.08): F, 31.3%. 1H NMR ꢀin CDCl3) d: 1.40±
1.18 ppm ꢀm, 4H); 1.94±1.50 ppm ꢀm, 6H); 9.62 ppm ꢀs,
1H, CHO). 13C NMR ꢀin CDCl3) d: 198.3 ppm ꢀq,
25.9 ppm ꢀs, C-3). 19F NMR ꢀin CDCl3) d: 74.5 ppm ꢀd,
4JHF ˆ 7:6 Hz , CF); 223.2 ppm ꢀtq, JHF ˆ 47:5 Hz ,
2
3
‡
4JHF ˆ 10:7 Hz , CHF). MS: 169 [1, ꢀM À H) ]; 155 [2,
2
‡
‡
‡
ꢀM À CH3) ]; 151 [4, ꢀM À F) ]; 150 [1, ꢀM À HF) ]; 142
‡
‡
[4, ꢀM À C2H4) ]; 137 [3, ꢀM À CH2F) ]; 135 [3,
‡
‡
1
ꢀM À CH3 À HF) ]; 131 [6, ꢀM À HF À F) ]; 130 [5,
3JCF ˆ 2:7 Hz, CHO); 126.0 ppm ꢀq, JCF ˆ 283:6 Hz ,
‡
‡
2
ꢀM À 2HF) ]; 122 [3, ꢀM À C2H4 À HF) ]; 117 [27,
CF3); 54.8 ppm ꢀq, JCF ˆ 22:6 Hz, C-1); 24.8 ppm ꢀs, C-
‡
‡
ꢀM À CH2F À HF) ]; 111 [9, ꢀM À 2HF À F) ]; 109 [7,
2); 24.6 ppm ꢀs, C-3); 21.3 ppm ꢀs, C-4). 19F NMR ꢀin
‡
‡
‡
‡
‡
ꢀM À CH2F À C2H4) ]; 103 ꢀ2); 101 [16, ꢀM À CF3) ]; 97
CDCl3) d: 73.6 ppm ꢀs, CF3). MS: 181 [1, ꢀM H) ]; 180
‡
‡
‡
‡
[21,ꢀM À CH2F À 2HF) ];95ꢀ5);91[4,ꢀM À CF3 À HF) ];
ꢀ0.5, M ꢀ); 179 [2, ꢀM À H) ]; 178 [6, ꢀM À 2H) ]; 160 [4,
‡
‡
‡
‡
‡
73 [10, ꢀM À CF3 À C2H4) ]; 69 ꢀ8, CF3 ); 67 ꢀ11); 57 ꢀ6,
ꢀM À HF) ]; 151 [3, ꢀM À CHO) ]; 141 [26, ꢀM À HF2) ];
‡ ‡
‡
‡
‡
‡
C4H9 ); 55 ꢀ6, C4H7 ); 45 ꢀ14, C3H9 ); 43 ꢀ5, C3H7 ); 42
ꢀ100, C3H6 );41ꢀ37, C3H5 );40ꢀ8, C3H4 );39ꢀ38, C3H3 );
132 [21, ꢀM À CO À HF) ]; 131 [23, ꢀM À COH À HF) ];
‡ ‡
‡
‡
‡
‡
121 [26, ꢀM À 2HF À F) ]; 111 [16, ꢀM À CO À 2HF) ];
‡
‡
33 ꢀ8, CH2F ).
101 ꢀ40); 99 ꢀ18); 92 [24, ꢀM À C2H4) ]; 91 ꢀ43); 81 ꢀ36);

A. Wolniewicz, W. Dmowski / Journal of Fluorine Chemistry 109 ,2001) 95±102
101
‡
‡
‡
69 ꢀ6, CF3 ); 55 ꢀ20, C4H7 ); 41 ꢀ48, C3H5 ); 39 ꢀ25,
‡
3.7.1. 1-Difluoromethyl-1-,trifluoromethyl)cyclohexane
,8a)
C3H3 ).
Yield: 61% ꢀ1.1 g, 5.4 mmol). Bp: 136±1388C. GLC
purity: >99%. Analysis: found: F, 46.1%. Calculated for
C8H11F5 ꢀ188.14): F, 47.0%. 1H NMR ꢀin CDCl3) d: 1.92±
3.6.2. 1-Formyl-1-,trifluoromethyl)cyclopentane ,7b)
Yield: 66% ꢀ1.1 g; 6.8 mmol). Bp: 127±1288C. GLC
purity: >98%. IR ꢀneat): n ˆ 1738:4 cmÀ1 ꢀns, CHO). Ana-
lysis: found: F, 34.5%. Calculated for C7H9F3O ꢀ166.14): F,
1.40 ppm ꢀm, 10H); 5.86 ppm ꢀt, 2JHF ˆ 54:9 Hz, 1H). 13
C
1
NMR ꢀin CDCl3) d: 127.7 ppm ꢀqt, JCF ˆ 283:8 Hz ,
1
1
34.3%. H NMR ꢀin CDCl3) d: 2.40±1.55 ppm ꢀm, 8H);
4JCF ˆ 3:6 Hz , CF); 116.0 ppm ꢀtq, JCF ˆ 248:5 Hz ,
3
9.70 ppm ꢀs, 1H, CHO); 13C NMR ꢀin CDCl3) d: 195.8 ppm
4JCF ˆ 2:6 Hz, CHF2); 46.9 ppm ꢀqt, JCF ˆ 18:3 Hz ,
2
3
1
ꢀq, JCF ˆ 2:7 Hz, CHO); 127.1 ppm ꢀq, JCF ˆ 280:8 Hz ,
CF3); 62.5 ppm ꢀq, 2JCF ˆ 23:8 Hz, C-1); 28.5 ppm ꢀs, C-2);
25.9 ppm ꢀs, C-3). 19F NMR ꢀin CDCl3) d: 71.4 ppm ꢀs,
2JCF ˆ 22:7 Hz, C-1); 24.6 ppm ꢀs, C-2); 24.0 ppm ꢀs, C-3);
20.8 ppm ꢀs, C-4). 19F NMR ꢀin CDCl3) d: 71.8 ppm ꢀt,
4JFF ˆ 9:6 Hz , CF); 127.8 ppm ꢀdq, JHF ˆ 54:7 Hz ,
2
3
‡
‡
‡
CF3). MS: 167 [2, ꢀM H) ]; 166 ꢀ51, M ꢀ); 165 [4,
4JFF ˆ 9:5 Hz , CHF). MS: 202 ꢀ6, M ꢀÁ); 182 [14, ꢀM
‡
2
‡
‡
‡
‡
‡
‡
‡
ꢀM À H) ]; 148 [8, ꢀM H2O) ]; 146 [9, ꢀM À HF) ];
ÀHF) ]; 163 [16, ꢀM À HF2) ]; 162 [11, ꢀM À 2HF) ];
‡ ‡
‡
‡
127 [4, ꢀM À HF2) ]; 126 [12, ꢀM À 2HF) ]; 125 [100,
151 [65, ꢀM À CHF2) ]; 150 [7, ꢀM À CHF2 À H) ]; 149
‡
‡
‡
ꢀM À H À 2HF) ]; 118 [21, ꢀM À CO À HF) ]; 117 [33,
ꢀ17); 131 [100, ꢁM À CHF2 À HF† ]; 113 ꢀ20,
‡
‡
‡
‡
M À CHO À HF ]; 115 ꢀ10); 105 ꢀ45); 98 [20,
M À CF3 À HF ); 111 [55, ꢀM À CHF2 À 2HF) ]; 93 [18,
‡ ‡
ꢀM À CO À 2HF) ]; 85 ꢀ57); 79 ꢀ13); 77 ꢀ43); 69 ꢀ12,
ꢀM À CF3 À 2HF) ];91ꢀ21);77ꢀ33);69ꢀ11, CF3 );67ꢀ22);
‡
‡
‡
‡
CF3 ); 67 ꢀ79); 43 ꢀ18, C3H7 ); 42 ꢀ86, C3H6 ); 41 ꢀ63,
C3H5 ); 40 ꢀ11, C3H4 ); 39 ꢀ51, C3H3 ).
65 ꢀ11); 59 ꢀ18); 56 ꢀ43); 55 ꢀ32); 51 ꢀ21, CHF2 ); 47 ꢀ11,
C3H7 ); 42 ꢀ17, C3H6 ); 41 ꢀ89, C3H5 ); 40 ꢀ7, C3H4 ); 39
‡
‡
‡
‡
‡
‡
‡
‡
ꢀ47, C3H3 ).
3.6.3. 1-Formyl-1-,trifluoromethyl)cyclobutane ,7c)
Yield: 43% ꢀ1.4 g; 9.2 mmol). Bp: 96±988C. GLC purity:
>98%. IR ꢀneat): n ˆ 1733:1 cmÀ1 ꢀns, CHO). Analysis:
found: F, 37.1%. Calculated for C6H7F3O ꢀ152.14): F,
3.7.2. 1-Difluoromethyl-1-,trifluoromethyl)cyclopentane
,8b)
Yield: 52% ꢀ0.58 g, 3.1 mmol). Bp: 91±928C. GLC pur-
ity: >99%. Analysis: found: F, 50.1%. Calculated for
C7H9F5 ꢀ188.14): F, 50.5%. 1H NMR ꢀin CDCl3) d:
1
37.5%. H NMR ꢀin CDCl3) d: 2.19±1.88 ppm ꢀm, 4H);
2.53±2.28 ppm ꢀm, 2H); 9.77 ppm ꢀs, 1H, CHO). 13C NMR
3
2
ꢀin CDCl3) d: 194.7 ppm ꢀq, JCF ˆ 3:1 Hz, CHO);
2.05±1.60 ppm ꢀm, 8H); 5.89 ppm ꢀt, JHF ˆ 55:8 Hz , 1H).
1
1
126.1 ppm ꢀq, JCF ˆ 279:1 Hz , CF); 54.8 ppm ꢀq,
13C NMR ꢀin CDCl3) d: 127.4 ppm ꢀqt, JCF ˆ 280:8 Hz ,
3
2JCF ˆ 26:6 Hz, C-1); 22.2 ppm ꢀs, C-2); 14.7 ppm ꢀs, C-
3). 19F NMR ꢀin CDCl3) d: 74.6 ppm ꢀs, CF3). MS: 153 ꢀ1,
4JCF ˆ 5:8 Hz , CF); 115.2 ppm ꢀtq, JCF ˆ 245:4 Hz ,
1
3
4JCF ˆ 3:2 Hz, CHF2); 55.4 ppm ꢀqt, JCF ˆ 20:4 Hz ,
2
‡
‡
‡
[M H] ); 152 ꢀ5, M ꢀ); 151 [4, ꢀM À H) ]; 137 ꢀ4); 132
2JCF ˆ 24:1 Hz, C-1); 28.0 ppm ꢀs, C-2); 26.5 ppm ꢀs, C-3).
‡
‡
‡
4
[11, ꢀM À HF) ]; 124 [6, ꢀM À CO) ]; 123 [58,
19F NMR ꢀin CDCl3) d: 73.2 ppm ꢀt, JFF ˆ 7:7 Hz , CF);
3
‡
‡
ꢀM À CHO) ]; 112 [28, ꢀM À 2HF) ]; 105 [17,
126.9 ppm ꢀdq, 2JFF ˆ 55:8 Hz ,4JFF ˆ 7:7 Hz, CHF2). MS:
‡
‡
‡
‡
‡
ꢀM À CO À F) ]; 104 [53, ꢀM À CO À HF) ]; 103 [84,
169[1,ꢀM À F) ];168[3,ꢀM À HF) ];167[3,ꢀM À H2F) ];
‡ ‡
‡
‡
ꢀM À CHO À HF) ]; 95 ꢀ22); 86 ꢀ10); 85 [21,
149 [15, ꢀM À HF2) ]; 148 [3, ꢀM À 2HF) ); 140 [4,
‡ ‡
‡
ꢀM À CO À HF2) ]; 84 [98, ꢀM À CO À 2HF) ]; 83 [100,
ꢀM À HF À C2H4) ]; 137 [6, ꢀM À CHF2) ]; 135 ꢀ9); 129
‡ ‡
‡
ꢀM À CHO À 2HF) ]; 77 ꢀ61); 76 ꢀ41); 75 ꢀ28); 69 ꢀ28,
[6, ꢀM À 2HF À F) ]; 127 [11, ꢀM À 3HF À H) ]; 117 [52,
‡ ‡
‡
CF3 ); 59 ꢀ32); 55 ꢀ35); 53 ꢀ30); 51 ꢀ23); 49 ꢀ44); 43 ꢀ23,
C3H7 ); 41 ꢀ40, C3H5 ); 40 ꢀ31, C3H4 ); 39 ꢀ45, C3H3 ).
ꢀM À CHF2 À 2HF) ]; 99 [29, ꢀM À CF3 À HF) ]; 97 [36,
‡ ‡
‡
‡
‡
‡
ꢀM À CHF2 À 2HF) ];79[19, ꢀM À CF3 À 2HF) ];77ꢀ26);
‡ ‡ ‡
69 ꢀ12, CF3 ); 51 ꢀ25, CHF2 ); 42 ꢀ100, C3H6 ); 41 ꢀ43,
C3H5 ); 40 ꢀ10, C3H4 ); 39 ꢀ47, C3H3 ).
‡
‡
‡
3.7. 1-Difluoromethyl-1-,trifluoromethyl)cycloalkanes
,8a±b)
1-Formyl-1-ꢀtri¯uoromethyl)cycloalkane 7a or 7b
ꢀ9 mmol) was placed in a 30 ml capacity stainless steel
autoclave ®tted with a needle valve, the autoclave was
cooled in an acetone-dry ice bath, evacuated, then sulphur
tetra¯uoride ꢀ4.3 g, 40 mmol) was condensed into it. The
autoclave was mechanically agitated and heated at 308C for
48 h. After completion of the reaction, gaseous products
were let off ꢀexcess SF4, SOF2, HF), and the residue was
distilled under atmospheric pressure ꢀsome amount of NaF
was added to bind free HF). Redistillation afforded com-
pounds 8a and b as volatile liquids. Due to high volatility, no
C and H analyses were determined.
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