1436
Russ.Chem.Bull., Int.Ed., Vol. 58, No. 7, July, 2009
Koldobskii et al.
yield of the mixture 5f and 6f was 2.15 g (76%), b.p. 53—60 °C
(1 Torr). Found (%): C, 42.19; H, 3.71; Br, 27.90; F, 20.35.
C10H10BrF3O. Calculated (%): C, 42.42; H, 3.57; Br, 28.22;
enꢀ2ꢀone (6l, a mixture of isomers 1 : 3). We failed in selective
bromination to the pure cycloadduct 4l, hence, an isomeric mixꢀ
ture, obtained by fractional distillation after performing the reꢀ
action according to general procedure, was characterized. The
yield of the mixture 5l and 6l was 1.73 g (57%), b.p. 60—65 °C
(1 Torr). Found (%): C, 31.44; H, 2.61; I, 41.90; F, 18.58.
C8H8IF3O. Calculated (%): C, 31.60; H, 2.66; I, 41.73; F, 18.75.
1H NMR, δ, 5l: 1.36 (s, 6 H, (CH3)2); 2.77 (s, 2 H, CH2).
1H NMR, δ, 6l: 1.73 (s, 3 H, CH3—C=C); 3.48 (s, 2 H, —CH2—);
4.90 (d, 1 H, H—C=C, J = 1.2 Hz); 5.16 (d, 1 H, H—C=C,
J = 1.2 Hz); 7.02 (s, 1 H, CH—CO). 13C NMR of the isomeric
mixture, δ: 20.4; 24.9; 39.1; 42.6; 46.6; 113.5; 114.6; 115.9; 118.1;
120.7; 126.4; 141.0; 141.5; 173.8; 175.3. IR (ν/cm–1): 1735; 1700;
1644; 1615; 1608.
1ꢀ(2ꢀIodospiro[3.5]nonꢀ1ꢀenꢀ1ꢀyl)ꢀ2,2,2ꢀtrifluoroethanone
(5m) and 5ꢀ(cyclohexꢀ1ꢀenꢀ1ꢀyl)ꢀ4ꢀiodoꢀ1,1,1ꢀtrifluoropentꢀ3ꢀ
enꢀ2ꢀone (6m) (a mixture of isomers 3 : 2). We failed in selective
bromination to the pure cycloadduct 5m, hence, an isomeric
mixture, obtained by fractional distillation after performing the
reaction according to general procedure, was characterized. The
yield of the mixture 5m and 6m was 2.20 g (64%), b.p. 85—90 °C
(1 Torr). Found (%): C, 38.11; H, 3.34; I, 37.05; F, 16.39.
C11H12IF3O. Calculated (%): C, 38.39; H, 3.52; I, 36.86; F,
16.56. 1H NMR, δ, 5m: 1.18—1.35 (m, 4 H, (CH2)2); 1.55—1.70
(m, 6 H, (CH2)3); 2.76 (s, 2 H, H2C(3)). 1H NMR, δ, 6m:
1.79—1.92 (m, 4 H, —(CH2)2—); 1.95—2.10 (m, 4 H,
CH2—C=C—CH2); 3.43 (s, 2 H, C=C—CH2—C=C); 5.59
(t, 1 H, —CH=C, J = 0.8 Hz); 7.04 (s, 1 H, C=CH—CO). IR
(ν/cm–1): 1720; 1700; 1652; 1615; 1608.
1
F, 20.13. H NMR, δ, 5f: 1.49—1.67, 1.74—1.88 (both m, 8 H,
(CH2)4); 2.72 (s, 2 H, H2C(3)). 1H NMR, δ, 6f: 1.92, 2.36 (both m,
6 H, —(CH2)3—); 3.39 (s, 2 H, C=C—CH2—C=C); 5.74 (t, 1 H,
—CH=C, J = 1.5 Hz); 6.81 (s, 1 H, C=CH—CO). IR (ν/cm–1):
1718 (C=O); 1645 (C=C); 1608 (C=C).
1ꢀ(2ꢀBromospiro[3.5]nonꢀ1ꢀenꢀ1ꢀyl)ꢀ2,2,2ꢀtrifluoroethanꢀ
one (5g). The yield of 5g was 2.13 g (73%), b.p. 76—78 °C
(1 Torr). Found (%): C, 44.23; H, 4.12; Br, 26.88; F, 19.03.
C11H12BrF3O. Calculated (%): C, 44.47; H, 4.07; Br, 26.89;
F, 19.18. 1H NMR, δ: 1.50—1.59, 1.62—1.68, 1.70—1.79,
1.87—1.98 (all m, 10 H, —(CH2)5—); 2.71 (s, 2 H, —CH2—).
13C NMR, δ: 23.9, 24.9, 33.2 (—(CH2)5—); 50.3 (C(3)); 50.8
(C(4)); 115.3 (q, CF3, JC,F = 288 Hz); 136.2, 146.2 (C=C);
174.6 (q, C=O, JC,F = 40 Hz). IR (ν/cm–1): 1708 (C=O);
1610 (C=C).
1ꢀ(7ꢀBromobicyclo[3.2.0]heptꢀ6ꢀenꢀ6ꢀyl)ꢀ2,2,2ꢀtrifluoroꢀ
ethanone (5h). The yield of 5h was 2.20 g (82%), b.p. 44—45 °C
(1 Torr). Found (%): C, 40.17; H, 2.89; Br, 29.81; F, 21.13.
C9H8BrF3O. Calculated (%): C, 40.18; H, 3.00; Br, 29.70;
F, 21.18. 1H NMR, δ: 1.31—1.44, 1.49—1.57, 1.75—1.90 (all m,
6 H, —(CH2)3—); 3.45 (dd, 1 H, H—C(4), J = 6.4 Hz, J = 3.4 Hz);
3.62 (dd, 1 H, HC(3), JC,H = 6.4 Hz, J = 3.4 Hz). 13C NMR, δ:
22.4, 24.7, 25.8 (—(CH2)3—); 47.1 (C(3)); 54.7 (C(4)); 115.9
(q, CF3, JC,F = 288 Hz); 138.0, 139.8 (C=C); 174.0 (q, C=O,
JC,F = 38 Hz). IR (ν/cm–1): 1706 (C=O); 1611 (C=C).
1ꢀ(7ꢀBromobicyclo[4.2.0]octꢀ7ꢀenꢀ7ꢀyl)ꢀ2,2,2ꢀtrifluoroꢀ
ethanone (5i). The yield of 5i was 2.12 g (75%), b.p. 53—54 °C
(1 Torr). Found (%): C, 42.62; H, 3.59; Br, 28.68; F, 20.00.
C10H10BrF3O. Calculated (%): C, 42.43; H, 3.56; Br, 28.23;
F, 20.13. 1H NMR, δ: 1.40—1.59, 1.71—1.95 (both m, 4 H each,
—(CH2)4—); 3.22 (dd, 1 H, J = 6.8 Hz, J = 4.2 Hz) C(4)H; 3.34
(dd, 1 H, HC(3), JC,H = 6.8 Hz, J = 4.2 Hz). 13C NMR, δ: 13.6;
13.8; 18.4; 19.0 (—(CH2)4—); 36.8 (C(4)); 43.9 (C(3)); 111.8
(q, CF3, JC,F = 288 Hz); 136.9; 138.3 (C=C); 169.7 (q, C=O,
JC,F = 38 Hz). IR (ν/cm–1): 1705 (C=O); 1605 (C=C).
4ꢀChloroꢀ1,1,1ꢀtrifluoroꢀ6ꢀmethylheptaꢀ3,6ꢀdienꢀ2ꢀone (6a).
The isomeric mixture of 5a and 6a (4 : 1, 10.00 g; see Table 1),
was thoroughly fractionally distilled in vacuo using a mirror disꢀ
tilling column. The yield of ene adduct 6a was 0.80 g (32% on
the rectification step), b.p. 59—60 °C (8 Torr). The product
contains about 5% of isomer 5a. Found (%): C, 45.13; H, 3.93;
F, 26.88. C8H8ClF3O. Calculated (%): C, 45.20; H, 3.79;
1
F, 26.81. H NMR, δ: 1.77 (s, 3 H, CH3—C=C); 3.28 (s, 2 H,
C=C—CH2—C=C); 4.93 (d, 1 H, H—C=C, J = 1.2 Hz); 5.08
(d, 1 H, H—C=C, J = 1.2 Hz); 6.70 (s, 1 H, C=CH—CO).
13C NMR, δ: 19.4 (CH3); 38.9 (CH2); 115.9, 122.7 (CH2=C);
117.5 (q, CF3, JC,F = 290 Hz); 144.0, 153.8 (C=C—Cl); 181.2
(q, C=O, JC,F = 40 Hz). IR (ν/cm–1): 1716 (C=O); 1648 (C=C);
1610 (C=C).
5ꢀ(Cyclopentꢀ1ꢀenꢀ1ꢀyl)ꢀ4ꢀchloroꢀ1,1,1ꢀtrifluoropentꢀ3ꢀenꢀ
2ꢀone (6c) was obtained similarly to compound 6a by rectificaꢀ
tion of the isomeric mixture 5c and 6c (1 : 2, 9.00 g). The yield of
product 6c was 2.89 g (48% on the rectification step), b.p. 49—50 °C
(1 Torr). Found (%): C, 50.40; H, 4.16; F, 23.73. C10H10ClF3O.
Calculated (%): C, 50.33; H, 4.22; F, 23.88. 1H NMR, δ: 1.84, 2.40
(both m, 6 H, —(CH2)3—); 3.35 (s, 2 H, C=C—CH2—C=C);
5.68 (t, 1 H, —CH=C, J = 1.6 Hz); 6.69 (s, 1 H, C=CH—CO).
13C NMR, δ: 24.9, 34.0, 35.2 (—(CH2)3—); 44.6 (—CH2—);
118.2 (q, CF3, JC,F = 288 Hz); 120.4, 131.6 (C=C in ring);
146.8, 155.3 (C=C—Cl); 181.9 (q, C=O, JC,F = 39 Hz). IR
(ν/cm–1): 1722 (C=O); 1654 (C=C); 1602 (C=C).
1ꢀ(2ꢀBromoꢀ3,4ꢀdimethylcyclobutꢀ1ꢀenꢀ1ꢀyl)ꢀ2,2,2ꢀtrifluoꢀ
roethanone (5j). The yield of 5j was 1.72 g (67%), b.p. 66—67 °C
(10 Torr). Found (%): C, 37.21; H, 3.08; F, 22.34. C8H8BrF3O.
1
Calculated (%): C, 37.38; H, 3.14; F, 22.17. H NMR, δ: 1.13
(d, 3 H, CH3C(4), J = 7.0 Hz); 1.21 (d, 3 H, CH3—C(3), J =
= 7.0 Hz); 3.23 (dq, 1 H, H—C(4), J = 7.0 Hz, J = 5.3 Hz); 3.38
(dq, 1 H, H—C(3), J =7.0 Hz, J = 5.3 Hz). 13C NMR, δ: 11.1,
12.6 (2 CH3); 40.1 (C(4)); 47.2 (C(3)); 115.3 (q, CF3, JC,F
=
= 290 Hz); 140.9; 142.5 (C=C); 174.2 (q, C=O, JC,F = 38 Hz).
IR (ν/cm–1): 1702 (C=O); 1605 (C=C).
1ꢀ(2ꢀBromoꢀ4ꢀbutylcyclobutꢀ1ꢀenꢀ1ꢀyl)ꢀ and 1ꢀ(2ꢀbromoꢀ3ꢀ
butylcyclobutꢀ1ꢀenꢀ1ꢀyl)ꢀ2,2,2ꢀtrifluoroethanone (5k, a mixture
of isomers 1 : 1). The yield of 5k was 1.60 g (56%), b.p. 59—61 °C
(1 Torr). Found (%): C, 42.03; H, 4.13; Br, 2809; F, 19.64.
C10H12BrF3O. Calculated (%): C, 42.13; H, 4.24; Br, 28.03;
F, 19.19. 1H NMR, δ: 0.91 (t, 6 H); 1.24—1.52 (m, 10 H); 1.78 (dt,
1 H, J = 12.0 Hz, J = 7.4 Hz); 1.92 (dt, 1 H, J = 12.0 Hz, J = 7.4 Hz);
2.62 (m, 2 H); 3.00—3.11 (m, 3 H); 3.21 (ddd, 1 H, J = 10.2 Hz,
J = 7.4 Hz, J = 4.8 Hz). 13C NMR, δ: 13.3; 13.9; 22.4; 22.5; 28.6;
28.9; 30.9; 31.5; 34.7; 42.9; 43.6; 49.2; 115.3; 115.7; 135.9; 136.2;
142.2; 142.3; 174.2; 175.0. IR (ν/cm–1): 1715; 1605.
1,1,1ꢀTrifluorobutꢀ3ꢀynꢀ2ꢀone (7). A solution of trifluoroꢀ
acetic acid (6.00 g, 0.052 mol) in ethyl benzoate (5.0 mL) was
added dropwise to a stirred with powerful magnetic stirrer soluꢀ
tion of acetylene 2 (15.00 g, 0.052 mol) in ethyl benzoate (10 mL)
at –10 °C, the reaction mixture was allowed to warm to 20 °C
and additionally stirred for 0.5 h. (A dense precipitate of trimeꢀ
1ꢀ(2ꢀIodoꢀ4,4ꢀdimethylcyclobutꢀ1ꢀenꢀ1ꢀyl)ꢀ2,2,2ꢀtrifluoroꢀ
ethanone (5l) and 4ꢀiodoꢀ1,1,1ꢀtrifluoroꢀ6ꢀmethylheptaꢀ3,6ꢀdiꢀ