ZORIN et al.
1530
from 50 to 280°C at a rate of 10 deg/min; carrier gas
helium, flow rate 1.1 mL/min.
24.79 (BrCH2), 173.57 (C=O). Mass spectrum, m/z
(Irel, %): 140/138 (46/47) [M]+, 96 (95), 95 (37), 94
(100), 93 (41), 81 (12), 79 (12), 56 (79), 45 (52), 44
(32), 43 (12), 42 (60), 41 (20), 40 (14).
The reactions of lithium acylate carbanions 2a–2c
with carbon tetrabromide (13) were carried out accord-
ing to the procedure described in [3] for analogous
reactions with carbon tetrachloride. The reactions in
the presence of hept-1-ene (13) were performed in
a similar way; an equimolar amount of compound 13
was added to the reaction flask together with carbon
tetrabromide. When the reaction was complete, the
organic phase was analyzed by GLC and GC/MS.
1
2-Bromobutanoic acid (10b). H NMR spectrum
(CF3COOH–CDCl3), δ, ppm: 1.21 t (3H, CH3), 1.96–
13
2.20 m (2H, CH2), 4.23 t (1H, CHBr). C NMR spec-
trum (CF3COOH–CDCl3), δC, ppm: 11.13 (CH3), 28.30
(CH2), 46.45 (CHBr), 177.97 (C=O). Mass spectrum,
m/z (Irel, %): 140 (51), 138 (53), 87 (39), 69 (18), 55
(9), 45 (51), 43 (38), 42 (28), 41 (100), 40 (12).
1
The H and 13C NMR spectra of 8a–8c, 10a–10c,
1
2-Bromo-2-methylpropanoic acid (10c). H NMR
15, and 16 were in agreement with those reported in
spectrum (CF3COOH–CDCl3), δ, ppm: 1.96 s (6H,
CH3). 13C NMR spectrum (CF3COOH–CDCl3), δC,
ppm: 30.16 (2C, CH3), 54.39 (CBr), 178.79 (C=O).
Mass spectrum, m/z (Irel, %): 121 (6), 123 (6), 87 (100),
59 (48), 45 (32), 43 (19), 42 (21), 41 (90), 40 (11).
[3, 6, 8, 9].
1
Butanedioic acid (8a). mp 188–189°C. H NMR
spectrum, δ, ppm: 2.40 s (4H, CH2). 13C NMR spec-
trum, δC, ppm: 28.54 (CH2), 179.63 (C=O). Mass spec-
trum, m/z (Irel, %): 101 (15), 100 (49), 74 (69), 72 (18),
56 (36), 55 (95), 46 (10), 45 (100), 44 (41), 43 (15), 42
(13), 40 (15).
1
1,1,1,3-Tetrabromooctane (15). H NMR spec-
trum (CDCl3), δ, ppm: 1.26 t (3H, CH3), 1.55–1.70 m
(4H, CH2), 1.75–1.95 m (2H, CH2), 2.15–2.35 m (2H,
CH2), 3.77 d.d (1H, 2-H, J = 16.17, 4.88 Hz), 4.11 d.d
(1H, 2-H, J = 16.17, 4.58 Hz), 4.45–4.52 m (1H,
2,3-Diethylbutanedioic acid (8b). mp 127–133°C.
1
meso-2,3-Diethylbutanedioic acid. H NMR spec-
13
CHBr). C NMR spectrum (CDCl3), δC, ppm: 14.75
trum, δ, ppm: 0.90 t (6H, CH3), 1.52–1.70 m (2H,
CH2), 1.70–1.87 m (2H, CH2), 2.63–2.70 m (2H, CH).
13C NMR spectrum, δC, ppm: 11.09 (CH3), 22.20
(CH2), 46.79 (CH), 182.08 (C=O). Mass spectrum, m/z
(Irel, %): 128 (25), 101 (44), 100 (13), 99 (21), 88 (19),
87 (30), 84 (50), 83 (34), 73 (37), 70 (20), 69 (75), 57
(10), 56 (46), 55 (100), 53 (13), 45 (28), 44 (26), 43
(32), 42 (43), 41 (65), 40 (16).
(CH3), 23.29 (CH2), 27.45 (CH2), 30.90 (CH2), 38.30
(CH2), 42.46 (CH2), 52.17 (CHBr), 63.04 (CBr3). Mass
spectrum, m/z (Irel, %): 199 (11), 189 (19), 187 (20),
108 (16), 107 (100), 83 (18), 79 (20), 67 (12), 65 (10),
56 (11), 55 (59), 53 (11), 43 (31), 41 (50).
1,1-Dibromo-2-pentylcyclopropane (16). 1H NMR
spectrum (CDCl3), δ, ppm: 0.91 t (3H, CH3), 1.17–
1.26 m (2H, CH2), 1.24–1.41 m (2H, CH2), 1.26–
1.57 m (2H, CH2), 1.31–1.42 m (2H, CH2), 1.34–
1.44 m (2H, CH2), 1.41–1.57 m (1H, CH). 13C NMR
spectrum (CDCl3), δC, ppm: 14.00 (CH3), 22.54 (CH2),
27.99 (CH2), 28.50 (CH2), 29.73 (CH2), 31.44 (CH),
32.57 (CH2), 43.03 (CBr2). Mass spectrum, m/z
(Irel, %): 109 (94), 84 (11), 83 (17), 69 (53), 67 (72), 56
(100), 55 (64), 53 (25), 51 (13), 43 (73), 42 (54), 41
(76), 39 (36), 32 (12).
1
(±)-2,3-Diethylbutandioic acid. H NMR spec-
trum, δ, ppm: 1.05 t (6H, CH3), 1.87–1.90 m (4H,
CH2), 2.70–2.80 m (2H, CH). 13C NMR spectrum,
δC, ppm: 13.03 (CH3), 22.36 (CH2), 48.48 (CH),
182.88 (C=O). Mass spectrum, m/z (Irel, %): 128
(20), 101 (14), 100 (10), 99 (26), 88 (35), 87 (53),
84 (28), 83 (34), 73 (65), 70 (33), 69 (100), 56 (36),
55 (88), 53 (12), 45 (28), 44 (39), 43 (29), 42 (37),
41 (58), 40 (23).
2,2,3,3-Tetramethylbutanedioic acid (8c).
FUNDING
1
mp 170–171°C. H NMR spectrum, δ, ppm: 1.20 s
(12H, CH3). 13C NMR spectrum, δC, ppm: 17.32 (CH3),
48.50, 179.36 (C=O). Mass spectrum, m/z (Irel, %): 88
(100), 87 (10), 84 (49), 83 (25), 73 (52), 71 (14), 70
(46), 69 (80), 59 (34), 57 (10), 56 (15), 55 (30), 45
(19), 44 (46), 43 (43), 42 (19), 41 (88), 40 (28).
This study was performed under financial support by the
Ministry of Science and Higher Education of the Russian
Federation in the framework of the base part of state
assignment in the sphere of research activity (project
no. 4.6451.2017/8.9).
1
2-Bromoacetic acid (10a). H NMR spectrum
CONFLICT OF INTERESTS
(CF3COOH–CDCl3), δ, ppm: 4.26 s (2H, BrCH2).
13C NMR spectrum (CF3COOH–CDCl3), δC, ppm:
The authors declare the absence of conflict of interests.
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 55 No. 10 2019