Hydroalumination of terminal β-acetylene alcohols with lithium aluminum hydride

Article abstract of DOI:10.1134/S1070363216020109

Hydrogenation of terminal β-acetylene alcohols with lithium aluminum hydride in THF has afforded homoallylic alcohols. Decomposition of the intermediate organoaluminum complex with deuterated water, iodine, or pyridinium dibromide has evidenced about the non-regioselective hydride attack at the triple bond.

Full text of DOI:10.1134/S1070363216020109

ISSN 1070-3632, Russian Journal of General Chemistry, 2016, Vol. 86, No. 2, pp. 267–272. © Pleiades Publishing, Ltd., 2016.
Original Russian Text © O.A. Garibyan, G.M. Makaryan, M.R. Ogannisyan, Zh.A. Chobanyan, 2016, published in Zhurnal Obshchei Khimii, 2016, Vol. 86,
No. 2, pp. 239–244.
Hydroalumination of Terminal β-Acetylene Alcohols
with Lithium Aluminum Hydride
O. A. Garibyan, G. M. Makaryan, M. R. Ogannisyan, and Zh. A. Chobanyan
Institute of Fine Organic Chemistry, Scientific Technological Center of Organic and Pharmaceutical Chemistry,
National Academy of Sciences of Armenia, ave. Azatutyan 26, Yerevan, 0014 Armenia
e-mail: hgaribyan@mail.ru
Received August 3, 2015
Abstract—Hydrogenation of terminal β-acetylene alcohols with lithium aluminum hydride in THF has
afforded homoallylic alcohols. Decomposition of the intermediate organoaluminum complex with deuterated
water, iodine, or pyridinium dibromide has evidenced about the non-regioselective hydride attack at the triple
bond.
Keywords: lithium aluminum hydride, terminal β-acetylene alcohol, hydroalumination-iodination, bromination-
hydroalumination, pyridinium dibromide
DOI: 10.1134/S1070363216020109
Homoallylic alcohols are valuable building blocks
for many natural products and biologically active
compounds [1, 2]. In recent decades, numerous
methods of synthesis of homoallylic alcohols have
been reported [3, 4], allylation of carbonyl compounds
being the most general one.
(Table 1). Structure of the obtained compounds was
confirmed by IR and H NMR spectroscopy data
(Table 2).
1
In order to determine the structure of the inter-
mediate organometallic complex, the latter was de-
composed with deuterated water, iodine, or pyridinium
dibromide. In all the cases, a mixture of regioisomeric
alkenols was obtained (Table 3). Their 1H NMR
spectral parameters are given in Table 4.
1H NMR spectrum of the reaction mixture after
decomposition with D2O contained the signals
corresponding to alcohols 3e (doublet at 4.95 ppm, J =
10.5 Hz, multiplet at 5.74–5.92 ppm) and 4e
(broadened singlets at 4.96 and 4.99 ppm). The spectra
of compounds 5–8 contained the signals of vinyl
protons in the range of 5.68–6.82 ppm (Table 4). In the
case of compounds 6 and 8, assignment of the signals
of vinyl protons in 1H NMR spectra was made
accounting for the downfield shifting the signal of the
proton trans-positioned with respect to the halogen
atom as compared with the cis-positioned proton. This
fact is well known in the chemistry of retinoids [13].
The reports on the methods of selective synthesis of
multifunctional homoallylic alcohols [5–7] as well as
the information about reducing the triple bond of the
terminal acetylene alcohols [8–12] have been scarce;
although it is obvious that modification of homoallylic
alcohols with various functional groups will
significantly increase their synthetic capacity.
The triple bond of the terminal α-acetylene alcohols
can be easily reduced by lithium aluminum hydride
(LAH) [8]. Halogenation of the intermediate organo-
aluminum complex indicates regioselective hydride
attack at the triple bond [9]. In addition, hydrogenation
of the terminal triple bond of monopropargyl glycol
ether [10] and 2-methylhepta-4,6-diyne-2-ol has been
known [11].
We investigated regio- and stereochemistry of
hydroalumination of terminal β-acetylene alcohols
with LAH. Reactions of acetylenic alcohols 1a–1f with
LAH (1 : 4) proceeded in anhydrous THF under reflux
to give homoallylic alcohols 2a–2f in high yields
When secondary (1b–1d) or tertiary (1e and 1f)
alcohols were introduced in the reaction instead of the
primary (1a) one, the ratio of the formed regioisomeric
alcohols changed sharply. In the case of the primary
267

268
GARIBYAN et al.
Scheme 1.
OH
R1
OH
Me
OH
Me
D
R2
Et
Et
D
2а_2f
3e
4e
H2O
D2O
R1
R2
OH
LiAlH4
R1
R2
R1
R2
Al_
H
O
Li
_
O
H
Al
H
H
1а_1f
B
А
I2
.
Br2 Py
OH
R1
OH
R1
R2
I
OH
Br
OH
R1
R2
R1
R2
R2
I
Br
5а_5f
7а_7f
6а_6f
8а_8f
R1 = R2 = H (a), R1 = H, R2 = Et (b), R1 = H, R2 = Ph (c), R1 = H, R2 = i-Bu (d), R1 = Me, R2 = Et (e), R1 + R2 = –(СН2)5– (f).
alcohol 1a, the ratio of regioisomers 5a, 6a and 7a, 8a
was of 1 : 9, i. e., the regioisomers with the halogen
atom located in the β-position with respect to the
hydroxyl group (6a and 8a) were predominantly
formed. The secondary alcohols 1b–1d also formed
halogenated alkenols with the ratio of regioisomers 5,
6 and 7, 8 of 5 : 1 (Scheme 1).
of halogenation of alcohol 1c, iodo- and bromo-
alkenols were isolated by column chromatography.
According to 1H NMR data, the double bond in
compounds 5a–5f and 7a–7f was cis-configured (3J =
7.2–7.5 Hz).
Only a single example of hydroalumination-iodina-
tion of the primary homopropargylic alcohol, but-3-yn-
1-ol, has been known so far [12]. In this case, di-
isobutylaluminum hydride has been used as the
In the case of the tertiary alcohols, the regioisomers
ratio was of 1 : 2. In all the cases, except the products
Table 1. Yields, boiling points and elemental analysis data for alkenols 2a–2f
Found, %
Calculated, %
Comp.
no.
bp, °C
(mmHg)
Rf (Et2O–
hexane, 1 : 3)
Yield, %
Formula
C
H
C
H
2а
2b
2c
2d
2e
2f
65–66 (700)
74–75 (40)
110–112 (5)
70–72 (20)
68–70 (10)
70–71 (10)
65.00
74.90
65.60
60.70
47.50
60.80
0.51
0.51
0.52
0.57
0.57
0.55
67.11
10.92
C4H8O
66.66
11.11
12.00
8.10
71.88
80.80
74.80
74.24
77.60
12.08
7.90
C6H12O
C10H12O
C8H16O
C7H14O
C9H16O
72.00
81.08
75.00
73.68
77.14
12.95
12.15
11.64
12.58
12.28
11.42
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HYDROALUMINATION OF TERMINAL β-ACETYLENE ALCOHOLS
Table 2. The IR and 1H NMR spectroscopy data for alkenols 2a–2f
269
Comp.
no.
ν, cm–1
δ, ppm (J, Hz)
2а 3300–3500 (O–H), 3095, 1610 2.50 q (2H, H2, J = 6.5), 3.41 t (2H, H1, J = 6.5 ), 3.41 br.s (1Н, ОН), 4.95 d
(CH=CH2), 1050 (C–O)
(1H, H4, J = 9.0), 4.99 d (1H, H4, J = 15.5), 5.80–5.95 m (1H, H3)
2b 3300‒3500 (O–H), 3095, 1610 0.91 t (3Н, Н1, J = 7.4), 1.31–1.66 m (2Н, Н2), 2.18–2.25 m (2Н, Н4), 2.90 br.s
(CH=CH2), 1050 (С–О)
(1Н, ОН), 3.40–3.48 m (1Н, Н3), 4.94 d (1Н, Н6, J = 16.6), 4.98 d (1Н, Н6, J =
10.2), 5.75–5.90 m (1Н, Н5)
2c 3300–3500 (O–H), 3100, 1620 2.45–2.58 m (2Н, H2), 4.54 t (1Н, H1, J = 6.5), 4.97 d (1Н, H4, J = 10.2), 5.01 d
(CH=CH2), 3040, 1560, 1510, 740, (1Н, H4, J = 16.9), 5.25 br.s (1Н, ОН), 5.72–5.83 m (1Н, H3), 7.12–7.35 m
690 (benzene ring), 1100 (C–O)
(5Н, C6H5)
2d 3550–3350 (OH), 3095, 1610 0.87 d (6Н, H7, С6–СН3, J = 6.5), 1.21–1.35 m (2Н, H5), 1.75–1.92 m (2Н, H3),
(CH=CH2), 1050 (C–O)
2.83 br.s (1Н, ОН), 3.42–3.50 m (1Н, H4), 4.94 d (1Н, H1, J = 16.5), 4.98 d
(1Н, H1, J = 10.0), 5.72–5.86 m (1Н, H2)
2e 3600–3400 (OH), 3100, 1610 0.87 t (3Н, H1, J = 7.5) 1.14 s (3Н, С3–СН3), 1.50 q.d (2Н, H2, J1 = 7.5, J2 =
(CH=CH2), 1050 (C–O)
1.7), 2.18 d (2Н, H4, J = 7.1), 3.20 br.s (1Н, ОН), 4.95 d (1Н, H6, J = 16.2),
4.99 d (1Н, H6, J = 7.3), 5.72–5.80 m (1Н, H5)
2f 3500–3300 (OH), 3100, 1620 1.05–1.70 m (10H, cyclohexyl), 2.15 d (2H, H1, J = 6.8), 3.50 br.s (1H, OH),
(CH=CH2), 1100 (C–O)
4.81 d (1H, H3, J = 15.6), 4.83 d (1H, H3, J = 8.5), 5.66–5.81 m (1H, H2)
Table 3. Yields and elemental analysis data for alkenols 5–8
Found, %
H
Calculated, %
H
Yield,
%
Rf (Et2O–
hexane, 1 : 3)
Comp. no.
Formula
C
Hlg
C
Hlg
5а + 6а
5b + 6b
5c + 6c
5d + 6d
5e + 6e
5f + 6f
65.00
44.2
0.59, 0.57
0.32, 0.39
0.58, 0.64
0.68, 0.52
0.68, 0.56
0.55, 0.61
0.55, 0.61
0.69, 0.72
0.55, 0.61
0.68, 0.56
0.68, 0.56
0.61, 0.53
24.62
32.20
43.63
37.96
35.12
40.83
32.42
39.80
53.09
46.80
43.92
49.84
3.60
4.62
4.01
5.25
5.92
5.98
4.88
5.64
5.01
7.42
6.91
7.03
64.40
56.30
46.61
50.80
53.04
47.38
53.04
43.48
35.38
38.93
41.52
36.92
C4H7IO
24.24
31.85
43.79
37.79
35.00
40.60
31.78
40.22
52.86
46.37
43.52
49.31
3.59
64.14
56.19
46.35
50.00
52.91
47.74
52.98
44.69
35.24
38.64
41.45
36.52
C6H11IO
C10H11IO
C8H15IO
C7H13IO
C9H15IO
C4H7BrO
C6H11BrO
C10H11BrO
C8H15BrO
C7H13BrO
C9H15BrO
4.86
56.8
4.01
33.33
45.50
55.10
52.40
45.70
65.0
5.90
5.41
5.63
7а + 8а
7b + 8b
7c + 8c
7d + 8d
7e + 8e
7f + 8f
4.63
6.14
4.84
24.62
55.28
67.00
7.24
6.79
6.84
hydrogenating agent, and the produced 4-iodobut-3-
to hydrogenate the triple bond of 2-(but-3-ynyloxy)tetra-
yn-1-ol has the E-configuration of the double bond.
hydro-2H-pyran 9 failed. Unlike terminal homo-
propargylic alcohols, in that case the triple bond was
completely inert to the hydrogenation.
To establish the role of the hydroxyl group in the
hydroalumination of terminal β-acetylene alcohols
with lithium aluminum hydride, we replaced it with
tetrahydropyranyl moiety (compound 9). Under the
studied conditions (THF, reflux, 12–14 h), the attempt
O
O
9
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270
GARIBYAN et al.
Table 4. The IR and 1H NMR spectroscopy data for alkenols 5–7
Comp.
ν, cm–1
no.
δ, ppm (J, Hz)
5а
3500–3300 (O–H), 3100, 1630 2.44 q (2Н, H2, J = 6.4), 2.94 br.s (1Н, ОН), 3.47 t (2Н, H1, J = 6.4), 6.26 d.t
(C=C), 1050 (C–O), 480 (C–I)
(1Н, H4, J1 = 7.3, J2 = 1.2), 6.33 d.t (1Н, H3, J1 = 7.3, J2 = 6.4)
3550–3350 (OH), 3080, 1620 0.88 t (3Н, H1, J = 6.5), 1.30–1.62 m (2Н, H2), 2.22–2.41 m (2Н, H4), 3.44–3.50
5b
(C=C), 1050 (C–O), 490 (C–I)
m (1Н, H3), 4.22 br.s (1Н, ОН), 6.23 d.t (1Н, H6, J1 = 7.2, J2 = 1.3), 6.35 d.t
(1Н, H6, J1 = 7.2, J2 = 6.5)
5c+6c 3500–3300 (OH), 3100, 1610 2.32–2.50 m (2Н, H2, 5c), 3.10–3.23 and 3.31–3.39 m (2Н, H2, 6c), 3.90 br.s
(C=C), 1100, 1050 (C–O), 3040, (1Н, ОН), 4.54 d.d (1Н, H1, J1 = J2 = 6.9, 6c), 4.75 d.d (1Н, H1, J1 = J2 = 6.9,
1560, 1510, 740, 690 (benzene 5c), 5.69 d (1Н, H4, J = 1.3, 6c), 6.04 q (1Н, H4, J = 1.3, 5c), 6.25 d.t (1Н, H4,
ring), 490 (C–I)
J1 = 7.5, J2 = 1.2, 5c), 6.33 d.t (1Н, H3, J1 = 7.5, J2 = 6.3, 5c), 7.10–7.37 m (5Н,
C6H5)
5d
5e
3500–3300 (OH), 3100, 1610 0.94 d (6Н, H7, С6–СН3, J = 6.4), 1.20–1.36 m (2Н, H5), 1.68–1.92 m (1Н, H6),
(C=C), 1050 (C–O), 480 (C–I)
2.05–2.22 m (2Н, H3), 3.04 br.s (1Н, ОН), 3.57–3.65 m (1Н, H4), 6.23 d.t (1Н,
H1, J1 = 7.2, J2 = 1.3), 6.35 d.t (1Н, H2, J1 = 7.2, J2 = 6.5)
35300–3300 (OH), 3070, 1600 0.88 t (3H, H1, J = 7.4), 1.22 s (3H, C3–CH3), 1.25–1.44 m (2Н, H2), 2.18 d
(C=C), 1050 (C–O), 490 (C–I)
(2Н, H4, J = 6.4), 2.97 br.s (1Н, ОН), 6.25 d.t (1Н, H6, J1 = 7.3, J2 = 1.4), 6.34
d.t (1Н, H5, J1 = 7.3, J2 = 6.4)
5f
3500–3300 (OH), 3060, 1610 1.20–1.66 m (10Н, cyclohexyl), 2.15 d (2Н, H1, J = 6.5), 3.03 br.s (1Н, ОН),
(C=C), 1060 (C–O), 490 (C–I)
3600–3400 (OH), 3080, 1600 2.44 t (2Н, H2, J = 6.4), 3.43 t (2Н, H1, J = 6.4), 4.25 br.s (1Н, ОН), 5.71 d (1Н,
(C=C), 1080 (C–O), 480 (C–I)
H4, J = 1.2), 6.13 d.t (1Н, H4, J1 = 1.2, J2 = 0.9)
6.13 d.t (1Н, H1, J1 = 7.3, J2 = 1.5), 6.26 d.t (1Н, H2, J1 = 7.3, J2 = 6.5)
6a
6b
3300–3500 (OH), 3080, 1610 0.88 t (3Н, H1, J = 6.4), 1.30–1.62 m (2Н, H2), 2.10–2.42 m (2Н, H4), 2.95 (1Н,
(C=C), 1040 (C–O), 490 (C–I)
ОН), 3.42–3.48 m (1Н, H3), 5.68 d (1Н, H6, J = 1.2), 6.13 d.t (1Н, H6, J1 = 1.2,
J2 = 0.9)
6d
3550–3350(OH), 3100, 1620 0.94 d (6Н, H7, С6–СН3, J = 6.5), 1.16–1.28 m (2Н, H5), 1.77–1.90 m (1Н, H6),
(C=C), 1090 (C–O), 480 (C–I)
3.08–3.20 m (2Н, H3), 3.31–3.50 m (1Н, H4), 4.12 br.s (1Н, ОН), 5.68 d (1Н,
H1, J = 1.1), 6.11 q (1Н, H1, J = 1.1)
6e
6f
3500–3300 (OH), 3080, 1630 0.88 t (3H, H1, J = 7.4), 1.14 s (3H, C3–CH3), 1.46 q (2H, H2, J = 7.4), 2.61 s
(C=C), 1030 (C–O), 490 (C–I)
(2H, H4), 3.87 br.s (1H, OH), 5.84 d (1H, H6, J = 1.1), 6.18 q (1H, H6, J = 1.1)
3300–3500 (OH), 3100, 1610 1.20–1.66 m (10Н, cyclohexyl), 2.61 s (2Н, H2), 3.42 br.s (1Н, ОН), 5.83 d
(C=C), 1070 (C–O), 490 (C–I)
(1Н, H3, J = 1.0), 6.15 q (1Н, H3, J = 1.0)
3500–3300 (OH), 3050, 1605 2.38 q (2Н, H2, J = 6.5), 3.02 br.s (1Н, ОН), 3.51 t (2Н, H1, J = 6.5), 6.24 d.t
(C=C), 1100 (C–O), 610 (C–Br)
(1Н, H4, J1 = 7.2, J2 = 1.2), 6.30 d.t (1Н, H3, J1 = 7.2, J2 = 6.5)
7а
7b
3500–3300 (OH), 3070, 1620 0.90 t (3Н, H1, J = 6.5), 1.55–1.90 m (2Н, H2), 2.23–2.31 m (2Н, H4), 3.08 br.s
(C=C), 1100 (C–O), 610 (C–Br)
(1Н, ОН), 4.02 m (1Н, H3), 6.21 d.t (1Н, H6, J1 = 6.9, J2 = 1.3), 6.27 d.t (1Н,
H5, J1 = 6.9, J2 = 6.2)
7c+8c 3550–3350 (ОН), 3100, 1630 2.31–2.47 m (2Н, H2, 7c), 2.56 br.s (1Н, ОН), 3.06–3.20 and 3.28–3.38 m (2Н,
(С=C), 3040, 1560, 1510, 740, 690 H2, 8c), 4.57 d.d (1Н, H1, J1 = = J2 = 6.8, 8c), 4.88 d.d (1Н, H1, J1 = J2 = 6.8,
(benzene ring), 1100, 1050 (C–O), 7c), 5.89 d (1Н, H4, J = 1.2, 8c), 6.07 q (1Н, H4, J = 1.3, 7c), 6.32 d.t (1Н, H4,
580 (C–Br)
J1 = 7.5, J2 = 1.3, 8c), 6.39 d.t (1Н, H3, J1 = 7.2, J2 = 6.5, 7c), 7.20–7.38 m (5Н,
C6H5)
7d
3300–3500 (ОН), 3050, 1630 0.95 d (6Н, H7, С6–СН3, J = 6.5), 1.20–1.32 m (2Н, H5), 1.65–1.87 m (1Н, H6),
(С=C), 1050 (C–O), 590 (C–Br)
2.12–2.28 m (2Н, H3), 3.24 br.s (1Н, ОН), 3.52–3.64 m (1Н, H4), 6.21 d.t (1Н,
H1, J1 = 7.2, J2 = 1.2), 6.34 d.t (1Н, H2, J1 = 7.2, J2 = 6.5)
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HYDROALUMINATION OF TERMINAL β-ACETYLENE ALCOHOLS
271
Table 4. (Contd.)
Comp.
no.
7e
ν, cm–1
δ, ppm (J, Hz)
3500–3300 (OH), 3080, 1610 0.88 t (3Н, H1, J = 6.5), 1.06 s (3H, C3–CH3), 1.36–1.48 m (2Н, H2), 2.23 d
(C=C), 1050 (C–O), 600 (C–Br)
(2Н, H4, J = 6.0), 2.84 br.s (1Н, ОН), 6.22 d.t (1Н, H6, J1 = 7.0, J2 = 1.2), 6.28
d.t (1Н, H5, J1 = 7.0, J2 = 6.0)
7f
3500–3300 (OH), 3050, 1630 1.05–1.70 m (10H, cyclohexyl), 2.18 d (2H, H1, J = 6.7), 3.67 br.s (1H, OH),
(C=C), 1100 (C–O), 630 (C–Br)
3500–3300 (OH), 3050, 1610 2.38 q (2Н, H2, J = 6.5), 3.45 t (2Н, H1, J = 6.5), 3.62 br.s (1Н, ОН), 6.53 d
(C=C), 1100 (C–O), 620 (C–Br)
(1Н, H4, J = 1.2), 6.82 d.t (1Н, H4, J1 = 1.2, J2 = 0.9)
3500–3300 (OH), 3100, 1610 0.95 t (3Н, H1, J = 6.4), 1.21–1.55 m (2Н, H2), 2.44 d.d (2Н, H4, J1 = 6.4, J2 =
(C=C), 1100 (C–O), 610 (C–Br)
6.11 d.t (1H, H3, J1 = 7.0, J2 = 1.5), 6.20 d.t (1H, H2, J1 = 7.0, J2 = 6.7)
8а
8b
0.9), 2.90 br.s (1Н, ОН), 3.40–3.48 m (1Н, H3), 5.38 d (1Н, H6, J = 1.2), 5.65
d.t (1Н, H6, J1 = 1.2, J2 = 0.9)
8d
8e
8f
3500–3300 (OH), 3060, 1620 0.94 d (6Н, H7, С6–СН3, J = 6.5), 1.16–1.28 m (2Н, H5), 1.46 br.s (1Н, ОН),
(C=C), 1100 (C–O), 620 (C–Br)
1.77–1.90 m (1Н, H6), 2.58–2.90 m (2Н, H3), 3.31–3.50 m (1Н, H4), 5.72 d (1Н,
H1, J = 1.0), 6.13 q (1Н, H1, J = 1.0)
3500–3300 (OH), 3050, 1630 0.88 t (3Н, H1, J = 6.5), 1.16 s (3H, C3–CH3), 1.41–1.52 m (2Н, H2), 2.53 s (2Н,
(C=C), 1100 (C–O), 590 (C–Br)
H4), 3.87 br.s (1Н, ОН), 5.50 d (1Н, H6, J = 1.2), 5.71 d.t (1Н, H6, J1 = 1.2, J2 =
0.9)
3500–3300 (OH), 3050, 1610 1.05–1.70 m (10H, cyclohexyl), 2.20 s (2H, H1), 3.63 br.s (1H, OH), 5.38 d
(C=C), 1100 (C–O), 620 (C–Br)
(1H, H3, J= 1.1), 5.58 q (1H, H3, J = 1.1)
The resistance to hydrogenation of terminal β-
acetylene alcohols with the hydroxyl group protected
with tetrahydropyranyl moiety, the presence of
deuterium, bromine, and iodine atoms at the β- and γ-
positions with respect to the hydroxyl group in the
reaction products, and the cis-configuration of the
double bond suggested that the hydride ion attack took
place simultaneously via two pathways. The reported
results, as well as the available data on the reduction of
α-acetylene alcohols [8] indicated that the hyd-
rogenation of terminal β-acetylene alcohols occurred
through the formation of cyclic organometallic com-
plexes A and B.
Clarus 400 instrument equipped with a flame
ionization detector (Elite-Wax ETR column, 60 m ×
0.32 mm; helium as the carrier gas, pressure of the
carrier gas 14.0 psi). TLC analysis was performed
using Silufol UV-254 plates, eluting with a hexane–
diethyl ether mixture and developing with potassium
permanganate solution. L40/100 silica was used for
column chromatography.
But-3-yn-1-ol 1a was purchased from Alfa Aesar.
β-Alcohols 1b–1f were synthesized via the
Reformatsky reaction of 1-bromobut-2-yne with the
corresponding carbonyl compounds [14]. 2-(But-3-
ynyloxy)tetrahydro-2H-pyran 9 was obtained by the
known procedure [15].
In summary, hydroalumination-halogenation of terminal
β-acetylene alcohols afforded β- and γ-halogenated
homoallylic alcohols that are of interest as precursors
for the synthesis of β- and γ-alkylhomoallylic alcohols,
components of many natural and biologically active
substances.
Hydroalumination of terminal β-acetylene alcohols
1a–1f. A solution of 50 mmol of alkynol 1a–1f in
anhydrous THF was added dropwise to a suspension of
200 mmol of lithium aluminum hydride in amhydrous
THF at 0 to –5°C under nitrogen. The mixture was
refluxed upon stirring during 12–13 h (5 h in the case
of alcohol 1c). The reaction progress was monitored by
TLC and GLC. After cooling to 0 to –5°C, 7.6 mL of
water, 7.6 mL of 15% sodium hydroxide, and 22.8 mL
of water were added. The reaction mixture was stirred
during 0.5 h. The formed precipitate was filtered off,
and the filtrate was extracted with diethyl ether. The
EXPERIMENTAL
1H NMR spectra were registered using a Varian
Mercury-300 VX spectrometer in DMSO-d6
(300.077 MHz) relative to internal TMS. IR spectra
(thin films) were recorded using a Specord 75-IR
spectrometer. GLC analysis was carried out using a
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272
GARIBYAN et al.
extract was washed with saturated sodium chloride
solution and dried with sodium sulfate. After the
solvents removal, the residue was distilled. Boiling
points, yields, Rf values, elemental analysis results, and
IR and H NMR spectroscopy for alkenols 2a–2f are
shown in Tables 1 and 2.
pyridinium bromide (prepared from 66 mmol of
pyridine and 44 mmol of bromine) in 10 mL of THF
was added dropwise. The reaction mixture was stirred
during 15 min at 0 to –5°C. Next, 6.8 mL of water,
6.8 mL of 15% aqueous sodium hydroxide solution,
and 20.4 mL of water were added. The formed
precipitate was filtered off, and the reaction products
were extracted with diethyl ether. The extract was
washed with dilute hydrochloric acid, saturated
solutions of sodium bicarbonate and sodium chloride,
and then dried over magnesium sulfate. The solvent
was removed, the residue was subject to chromato-
graphy (hexane : diethyl ether = 19 : 1). Yields, Rf
values, elemental analysis results, and IR and 1H NMR
spectroscopy data for bromalkenols 7a–7f and 8a–8f
are shown in Tables 3 and 4.
1
A mixture of deuteroalcohols 3e and 4e was
obtained in a ratio of 1 : 2 when treating the reaction
mixture with D2O. 1H NMR spectrum (CDCl3), δ, ppm
(J, Hz): 0.86 t (3H, H1, J = 6.5), 1.07 s (3H, C3–CH3),
1.37 q (2H, H2, J = 6.5), 2.10–2.14 m (2H, H4), 3.40
br.s (1H, OH), 4.95 d (1H, H6, J = 10.5, 3e), 5.74–5.92
m (1H, H5, 3e), 4.96 br.s (1H, H6, 4e), 4.99 br.s (1H,
H5, 4e).
Hydroalumination-iodination of terminal β-
acetylene alcohols 1a–1f. A solution of 50 mmol alk-
3-yn-1-ol 1a–1f in anhydrous THF was added
dropwise to a suspension of 200 mmol of lithium
aluminum hydride in anhydrous THF at 0°C under
nitrogen. The reaction mixture was refluxed upon
stirring during 12–13 h (6 h in the case of alcohol 1f).
After cooling to –10 to –5°C, 200 mmol of ethyl
acetate was added dropwise. The reaction mixture was
incubated at the same temperature during 0.5 h, and
then cooled to –10°C. Next, 100 mmol of crushed
iodine was added portionwise over 0.5 h. The reaction
mixture was stirred during 1 h at –10 to 0°C and then
treated with a saturated solution of sodium thiosulfate.
The formed precipitate was filtered off, and the
reaction products were extracted with diethyl ether.
The extract was washed with saturated sodium
thiosulfate solution, then with saturated sodium
chloride solution, and dried over magnesium sulfate.
The solvent was removed to obtain the mixture of
iodalkenols 5a–5f and 6a–6f. The individual isomers
were isolated by column chromatography (hexane :
diethyl ether = 19 : 1). Yields, Rf values, elemental
REFERENCES
1. Smith, A.B., Adams, C.M., Barbosa, S.A.I., and
Degnan, A.P., J. Am. Chem. Soc., 2003, vol. 125,
p. 350. DOI: 10.1021/ja0289649.
2. Hornberger, K.R., Hamblet, C.L., and Leighton, J.L.,
J. Am. Chem. Soc., 2000, vol. 122, p. 12894. DOI:
10.1021/ja003593m.
3. Yamamoto, Y. and Asao, N., Chem. Rev., 1993, vol. 93,
p. 2207. DOI: 10.1021/cr00022a010.
4. Denmark, S.E. and Fu, J.P., Chem. Rev., 2003, vol. 103,
p. 2763. DOI: 10.1021/cr020050h.
5. Chang, K.-J., Rayabarapu, D.K., Yang, F.-Y., and
Cheng, C.-H., J. Am. Chem. Soc., 2005, vol. 127, p. 126.
DOI: 10.1021/ja044662q.
6. Flamme, E.M. and Roush, W.R., J. Am. Chem. Soc.,
2002, vol. 124, p. 13644. DOI: 10.1021/ja028055j.
7. Cho, H.Y. and Morken, J.P., J. Am. Chem. Soc., 2008,
vol. 130, p. 16140. DOI: 10.1021/ja806113v.
8. Grant, B. and Djerassi, C., J. Org. Chem., 1974, vol. 39,
no. 7, p. 968. DOI: 10.1021/jo00921a024.
9. Garibyan, O.A., Makaryan, G.M., Kiniyan, F.S., and
Chobanyan, Zh.A., Khim. Zh. Armenii, 2009, vol. 62,
nos. 3–4, p. 369.
10. Gharibyan, H.A., Petrosyan, A.P., Makaryan, G.M.,
Hovhannisyan, M.R., and Chobanyan, Zh.A., Russ. J.
Gen. Chem., 2013, vol. 83, no. 1, p. 143. DOI: 10.134/
S1070363213010295.
1
analysis results, and IR and H NMR spectroscopy
data for iodalkenes 5a–5f and 6a–6f are shown in
Tables 3 and 4.
Hydroalumination-bromination of terminal β-
acetylene alcohols 1a–1f. A solution of 44 mmol of
alk-3-yn-1-ola 1a–1f in anhydrous THF was added
dropwise to a suspension of 176 mmol of lithium
aluminum hydride in anhydrous THF at 0 to –5°C
under nitrogen. The reaction mixture was refluxed
during 12–13 or 6 h (1f) upon stirring. After cooling to
–10 to –5°C, 176 mmol of ethyl acetate was added
dropwise. The reaction mixture was incubated at the
same temperature during 0.5 h, and then a solution of
11. Garibyan, O.A., Khim. Zh. Armenii, 2010, vol. 63,
nos. 3–4, p. 506.
12. Chong, J.M. and Heuft, M.A., Tetrahedron, 1999, vol. 55,
no. 50, p. 14243. DOI: 10.1016/s0040-4020(99)00899-6.
13. Mousseron-Canet, M. and Mani, J.D., Bull. Soc. Chim.,
1966, no. 10, p. 3285.
14. Sutherland, O.I., Comprehensive Organic Chemistry,
Pergamon Press, 1979.
15. Henbest, H.B., Jones, E.R.H., and Walls, I.M.S.,
J. Chem. Soc., 1950, p. 3646. DOI: 1039/jr9500003646.
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