Wittig olefination of menthone lactol and its aluminate

Article abstract of DOI:10.1007/s10600-013-0444-0

Features of the Wittig olefination reaction of menthone lactol and its aluminate by several n-alkylidenetriphenylphosphoranes were studied. The product of the reaction with ethylidenetriphenylphosphorane was used in the synthesis of the sex pheromone of p

Full text of DOI:10.1007/s10600-013-0444-0

Chemistry of Natural Compounds, Vol. 48, No. 6, January, 2013 [Russian original No. 6, November–December, 2012]
WITTIG OLEFINATION OF MENTHONE LACTOL
AND ITS ALUMINATE
*
G. Yu. Ishmuratov, V. A. Vydrina, I. S. Nazarov,
UDC 547.596.2
Yu. A. Galkina, M. P. Yakovleva, I. F. Lobko,
R. R. Muslukhov, and A. G. Tolstikov
Features of the Wittig olefination reaction of menthone lactol and its aluminate by several
n-alkylidenetriphenylphosphoranes were studied. The product of the reaction with
ethylidenetriphenylphosphorane was used in the synthesis of the sex pheromone of peach leaf miner Lyonetia
clerckella.
Keywords: menthone lactol and its aluminate, Wittig olefination, hydride reduction, pheromone, synthesis.
We reported earlier [1, 2] on the olefination of the hydride reduction product of (ꢀ)-menthone lactone (1) by an
equimolar amount of diisobutylaluminum hydride (DIBAH), i.e., aluminate (2), by C - and
6
C -n-alkylidenetriphenylphosphoranes in the targeted synthesis of sex pheromones of pine sawflies of the genera Diprion
1
6
and Neodiprion and the German cockroach Blatella germanica L. Furthermore, it was shown [3] that
methylidenetriphenylphosphorane reacted with menthone lactol aluminate (2) not as an olefination agent but as a hydride,
forming 3R,7-dimethyloctane-1,6S-diol (3).
(
CH ) CH
2 n 3
a
b
OH
O
OAlBu2i
+
O
OH
OH
O
1
2
3
4a - d
c
98%
b
OH
O
+
4a - f
5
5 - 60%
O
OH
n = 0 (a), 1 (b), 2 (c), 3 (d), 4 (e), 14 (f)
5
a
5b
i
i
a. 1 equiv. Bu AlH, THF, –70ꢁC; b. Me(CH ) CH=PPh , THF, –70ꢁ ꢂ20ꢁC; c. Bu AlH, THF, –78ꢁC, then H O
2
2 n
3
2
2
We expanded the scope of the employed olefination reagents and found that C –C -n-alkylidenetriphenylphosphoranes
2
5
(
like C - and C - [1, 2]) formed primarily the corresponding unsaturated alcohols (4a–d) with approximately equal amounts
6 16
of the Z- and E-isomers. The yield of the isomers was less than 60% whereas a significant quantity (up to 40%) of the
reduction product, diol 3, was formed as a side product (Table 1).
It could be assumed from this that CH =PPh , C –C -, and C -phosphoranes could act as reducing agents. We
2
3
2
6
16
studied the reaction of these n-alkylidenetriphenylphosphoranes with menthone lactol (5) itself in order to exclude an effect of
the aluminate component. Compound 5 was prepared by low-temperature (ꢀ70°C) reduction of 1 by DIBAH in THF and
existed according to the literature [4] as a 1:1 mixture of 7S-isopropyl-4R-methyloxepan-2S-ol (5a) and 6S-hydroxy-3R,7-
dimethyloctanal (5b). It was established that the last reacted to form exclusively the corresponding olefinic alcohols (4a–f)
with the same stereoselectivity but in higher yields than for the aluminate (2) (60–88%, Table 1).
Institute of Organic Chemistry, Ufa Scientific Center, Russian Academy of Sciences, 450054, Ufa, Prosp. Oktyabrya,
71, fax: (3472) 35 60 66, e-mail: insect@anrb.ru. Translated from Khimiya Prirodnykh Soedinenii, No. 6, November–December,
2
012, pp. 869–872. Original article submitted May 23, 2012.
0
009-3130/13/4806-0981 ©2013 Springer Science+Business Media New York
981

TABLE 1. Dependence of Yields of Reaction Products of Menthone Lactol (5a, b) and Its Aluminate (2) on the Nature of the
Olefination Agent (R–CH=PPh ) under Wittig Reaction Conditions
3
Yield of olefination products (4a–f), %
menthone lactol (5a, b) aluminate (2)
61 53
Yield of aluminate (2) reduction
product, diol (3), %
2 n 3
Me(CH ) CH=PPh
n = 0 (a)
n = 1 (b)
n = 2 (c)
n = 3 (d)
n = 4 (e)
n = 14 (f)
23
20
24
40
38
50
62
75
74
88
78
51
60
58
58 [1]
42 [2]
a
b
c
d
OH
OH
O
CO Pr
i
9
4%
96%
72%
2
4
a (Z/E ~ 1:1)
6
7
8
e, f
0%
g
Br
7
71%
2
CO H
9
10
S-11
a. H , Pd/C, EtOH; b. PCC, CH Cl ; c. MCPBA, CHCl ; d. KOH, H O; e. Ag O, CCl ; f. Br ;
2
2
2
3
2
2
4
2
g. CH =CH(CH ) MgBr, CuI – 2,2ꢃbipy, THF, 2ꢁ ꢂ20ꢁC
2
2 9
In our opinion, formation of 3 from 2 was related to its reduced reactivity at low temperatures for
n-alkylidenetriphenylphosphoranes whereas at temperatures increased to ambient it probably eliminates isobutylene to form
aluminum hydrides that facilitate the reduction, as noted by us earlier [4].
Thus, use of menthone lactol (5a, b) instead of the aluminate (2) in the olefination reaction enabled the yield of the
corresponding unsaturated alcohols (4a–d) to be increased by 10–30%.
One of the obtained unsaturated alcohols, 2,6R-dimethyldec-8-en-3S-ol (4a), was used in the synthesis of the sex
pheromone of peach leaf miner Lyonetia clerckella (11). Hydrogenation of 4a, oxidation of the hydroxyl in its saturated
analog (6), and incorporation of the resulting ketone (7) in a Baeyer–Villager reaction gave isopropyl-4S-methyloctanoate (8).
Basic hydrolysis of 8 led to the corresponding acid (9), which was incorporated in a Hunsdiecker reaction to yield 1-bromo-
3
1
S-methylheptane (10). Combination with 10-undecen-1-ylmagnesium bromide with catalysis by CuI:2,2ꢃ-bipyridyl afforded
4S-methyloctadec-1-en (11) in overall yield of 19.3% calculated for (ꢀ)-menthone lactone (1).
EXPERIMENTAL
NMR spectra were obtained on a Bruker AM-300 spectrometer (300 MHz for H; 75.47, for 13C). Resonances in
1
NMR spectra were assigned and SSCC were determined using 2D COSY (CꢀH) and COSY (HꢀH) correlation spectroscopy
1
3
and double resonance. C NMR spectra were recorded with broad-band proton decoupling and in JMOD mode. The internal
standard was Me Si. Chromatography was carried out on Chrom-5 [column length 1.2 m, stationary phase silicone SE-30
4
(
5%) on Chromaton N-AW-DMCS (0.16-0.20 mm), operating temperature 50–300°C] and Chrom-41 [column length 2.4 m,
stationary phase PEG-6000 (5%) on Inerton AW-DMCS (0.125–0.160 mm), operating temperature 50–200°C] instruments
with He carrier gas. Column chromatography was performed over Lancaster silica gel (60–200 ꢄm). TLC analysis was
carried out on Sorbfil UV-254 plates (Krasnodar). Optical rotation was measured on a Perkin–Elmer 241-MC polarimeter.
Elemental analyses of all compounds corresponded to those calculated.
7
S-Isopropyl-4R-methyloxepan-2S-ol (5a) and 6S-Hydroxy-3R,7-dimethyloctanal (5b). A solution of
(
ꢀ)-menthone lactone (1, 2.00 g, 11.8 mmol) that was prepared from l-menthol according to the literature [2] in anhydrous
THF (40 mL) at ꢀ70°C was treated dropwise with a solution (73%) of DIBAH (3.0 mL, 12.0 mmol) in toluene. After the
lactone was fully converted (15 min, TLC), the mixture was poured onto ice (10 mL), diluted with t-BuOMe (50 mL), filtered
982

through a layer of Al O (5 cm), dried over MgSO , and evaporated to afford a 1:1 mixture of lactol (5a) and hydroxyaldehyde
2
3
4
1
3
(
5b) (1.93 g, 98%). The PMR and C NMR parameters of 5a and 5b were identical to those reported previously [4].
Diisobutyl-(7S-isopropyl-4R-methyloxepan-2S-oyl)aluminum (2). Asolution of 1 (1.00 g, 5.9 mmol) in anhydrous
CH Cl (24 mL) at ꢀ70°C was treated dropwise with a solution (73%) of DIBAH (1.5 mL, 6.0 mmol) in toluene and stirred for
2
2
1
3
1
1
5 min. A sample was placed into an ampul. The NMR spectra were recorded. C NMR spectrum (C D , ꢅ, ppm): 18.76 and
9.44 [both q, (CH ) CH], 23.66 (q, 4-CH ), 30.46 (t, C-5), 30.95 (d, C-4), 33.49 [d, (H C) CH], 35.87 (t, C-6), 45.71 (t,
6 6
3
2
3
3
2
C-3), 82.35 (d, C-7), 97.78 (d, C-2), i-BuO: 23.20 (t, CH ), 25.98 (d, CH), 28.55 (q, 2CH ).
2
3
General Method for Wittig Olefination. a. A suspension of phosphonium salt (6.5 mmol) in anhydrous THF
15 mL) at ꢀ70°C was treated with a solution of n-BuLi (5.6 mL, 1.17 M, 6.5 mmol) in hexane, held for 1 h at room temperature,
(
cooled to ꢀ70°C, treated sequentially with a solution of 1 (1.00 g, 5.9 mmol) in anhydrous THF (6 mL) and a solution (73%)
of DIBAH (3.0 mL, 12.0 mmol) in toluene, held at ꢀ70°C for 1 h and at 20°C for 16 h, treated with cold H O (12 mL), and
2
filtered through a Schott filter. The solid was rinsed with t-BuOMe (50 mL). The filtrate was dried over Na SO and evaporated.
2
4
The residue was diluted with t-BuOMe (50 mL), filtered through a layer of Al O (5 cm), and evaporated to afford a mixture
2
3
of unsaturated alcohols 4a–d and diol 3.
b. A suspension of phosphonium salt (6.5 mmol) in anhydrous THF (15 mL) at ꢀ70°C was treated with a solution of
n-BuLi (5.6 mL, 1.17 M, 6.5 mmol) in hexane, held for 1 h at room temperature, cooled to ꢀ70°C, treated with a solution of
menthone lactol (5, 1.00 g, 5.8 mmol) in anhydrous THF (6 mL), held at ꢀ70°C for 1 h and at 20°C for 16 h, treated with H O
2
(
2 mL), diluted with t-BuOMe (50 mL), dried over Na SO , and evaporated. The residue was diluted with t-BuOMe (50 mL),
2 4
filtered through a layer of Al O (5 cm), and evaporated to afford unsaturated alcohols 4a–f.
2
3
2
,6R-Dimethyldec-8-en-3S-ol (4a). Prepared by method a (0.58 g, 53%) and method b (0.65 g, 61%), R 0.74
f
(
PE:MTBE, 2:1). PMR spectrum (CDCl , ꢅ, ppm): 0.77–0.88 (9H, m, H-1, 2-CH , 6-CH ), 0.9–1.7 (8H, m, H-2, H-4ꢀH-6,
3 3 3
1
3
H-10), 1.98–2.05 (2H, m, H-7), 3.35–3.55 (1H, m, H-3), 5.18 (1H, s, OH), 5.43–5.79 (2H, m, H-8, H-9). C NMR spectrum
CDCl , ꢅ, ppm): 16.90, 18.92, and 19.59 (all q, C-1, 2-CH , 6-CH ), 12.85 (q, C-10), 31.78 (t, C-4), 32.87 (t, C-5), 33.29 (d,
(
3
3
3
C-6), 33.56 (d, C-2), 39.84 (t, C-7), 67.65 (d, C-3), 124.52 [125.9] (d, C-9), 129.19 [129.82] (d, C-8).
2
,6R-Dimethylundec-8-en-3S-ol (4b). Prepared by method a (0.60 g, 51%) and method b (0.71 g, 62%), R 0.75
f
(
PE:MTBE, 2:1). PMR spectrum (CDCl , ꢅ, ppm): 0.75–0.85 (12H, m, H-1, 2-CH , 6-CH , H-11), 0.9–1.7 (6H, m, H-2,
3 3 3
1
3
H-4ꢀH-6), 1.98–2.05 (4H, m, H-7, H-10), 3.35–3.55 (1H, m, H-3), 5.18 (1H, s, OH), 5.40–5.75 (2H, m, H-8, H-9). C NMR
spectrum (CDCl , ꢅ, ppm): 18.21, 18.84, and 19.65 (all q, C-1, 2-CH , 6-CH ), 16.86 (q, C-11), 27.73 [33.76] (t, C-10), 31.34
3
3
3
(
(
t, C-4), 33.20 (d, C-6), 33.38 (t, C-5), 33.67 (d, C-2), 43.14 (t, C-7), 76.84 (d, C-3), 128.46 [128.30] (d, C-8), 134.05 [134.19]
d, C-9).
2
,6R-Dimethyldodec-8-en-3S-ol (4c). Prepared by method a (0.65 g, 52%) and method b (0.92 g, 75%), R 0.75
f
(
PE:MTBE, 2:1). PMR spectrum (CDCl , ꢅ, ppm): 0.75–0.85 (12H, m, H-1, 2-CH , 6-CH , H-12), 0.9–1.7 (8H, m, H-2,
3 3 3
H-4ꢀH-6, H-11), 1.98–2.05 (4H, m, H-7, H-10), 3.35–3.55 (1H, m, H-3), 5.18 (1H, s, OH), 5.48 (2H, m, H-9, H-10).
1
3
C NMR spectrum (CDCl , ꢅ, ppm): 17.02 (q, C-14), 18.30, 18.80, and 19.60 (all q, C-1, 2-CH , 6-CH ), 31.30 (t, C-4),
3
3
3
2
(
6.20 (t, C-11), 33.16 (d, C-6), 33.40 (t, C-10), 33.00 (t, C-5), 33.43 (d, C-2), 40.20 (t, C-7), 68.30 (d, C-3), 128.30 [128.15]
d, C-8), 132.00 [132.25] (d, C-9).
,6R-Dimethyltridec-8-en-3S-ol (4d). Prepared by method a (0.78 g, 58%) and method b (0.97 g, 74%), R 0.75
2
f
(
PE:MTBE, 2:1). PMR spectrum (CDCl , ꢅ, ppm): 0.75–0.90 (12H, m, H-1, 2-CH , 6-CH , H-13), 0.9–1.7 (10H, m, H-2,
3
3
3
H-4ꢀH-6, H-11, H-12), 1.98–2.50 (4H, m, H-7, H-10), 3.35–3.55 (1H, m, H-3), 5.18 (1H, s, OH), 5.49 (2H, m, H-9, H-10).
1
3
C NMR spectrum (CDCl , ꢅ, ppm): 16.90 (q, C-13), 18.20, 18.70, and 19.50 (all q, C-1, 2-CH , 6-CH ), 31.10 (t, C-12),
3
3
3
3
1
1.40 (t, C-4), 31.5 (t, C-11), 33.10 (d, C-6), 33.27 (t, C-10), 36.15 (t, C-5), 33.27 (d, C-2), 43.00 (t, C-7), 69.88 (d, C-3),
28.29 [128.19] (d, C-8), 131.95 [132.05] (d, C-9).
,6R-Dimethyltetradec-8-en-3S-ol (4e). Prepared by method b (1.23 g, 74%), R 0.77 (PE:MTBE, 2:1).
2
f
1
3
PMR spectral parameters were identical to those published earlier [1]. C NMR spectrum (CDCl , ꢅ, ppm): 15.09 (q, C-14),
3
1
8.36, 18.85, and 19.62 (all q, C-1, 2-CH , 6-CH ), 23.00 (t, C-13), 28.90 (t, C-11), 29.30 (t, C-10), 30.50 (t, C-12), 31.80 (t,
3 3
C-4), 33.60 (d, C-6), 33.70 (t, C-5), 33.97 (d, C-2), 40.00 (t, C-7), 76.90 (d, C-3), 128.20 [128.00] (d, C-8), 131.20 [131.45] (d,
C-9).
2
,6R-Dimethyltetracos-8-en-3S-ol (4f). Prepared by method b (1.72 g, 78%), R 0.80 (PE:MTBE, 2:1). PMR and
f
1
3
C NMR spectral parameters were identical to those published earlier [2].
2
0
3
R,7-Dimethyl-1,6S-octanediol (3). R 0.10 (PE:EtOAc, 7:3), [ꢆ] ꢀ10.3° (c 2.43, CHCl ). IR and NMR spectral
f D 3
parameters were identical to those published earlier [1].
983

2
,6S-Dimethyldecan-3S-ol (6). Unsaturated alcohol 4a (2.50 g, 13.8 mmol) in anhydrous EtOH (50 mL) was
hydrogenated in the presence of 10% Pd/C (5.3 mmol) for 24 h and filtered. The filtrate was evaporated to afford 6 (2.41 g,
2
1
ꢀ1
9
0
(
4%), [ꢆ] ꢀ5.10° (c 3.16, CHCl ). IR spectrum (KBr, ꢇ, cm ): 3500–3200 (OH). PMR spectrum (CDCl , ꢅ, ppm): 0.68–
D 3 3
.78 (12H, m, H-1, 2-CH , 6-CH , H-10), 0.94–1.12 (10H, m, H-4, H-5, H-7ꢀH-9), 1.48 and 1.66 (2H, m, H-6, H-2), 3.30
1H, br.s, OH), 3.48 (1H, m, H-3). C NMR spectrum (CDCl , ꢅ, ppm): 14.14 (q, C-10), 16.91, 18.95 (both q, C-1, 2-CH ),
3
3
1
3
3
3
1
7
9.78 (q, 6-CH ), 23.02 (t, C-8), 29.28, 29.70, 31.68 (all t, C-5, C-7, C-9), 32.94, 33.29 (both d, C-2, C-6), 36.59 (t, C-4),
7.20 (d, C-3).
3
2
,6S-Dimethyldecan-3S-one (7). A suspension of PCC (4.16 g, 19.0 mmol) in anhydrous CH Cl (10 mL) at room
2 2
temperature was treated dropwise with a solution of 6 (2.31 g, 12.4 mmol) in CH Cl (6 mL), stirred for 2 h, diluted with Et O
2
2
2
2
1
(
10 mL), filtered through a layer of Al O , and evaporated to afford 7 (2.20 g, 96%), [ꢆ] +2.10° (c 2.9, CHCl3).
2 3 D
ꢀ1
IR spectrum (KBr, ꢇ, cm ): 1717 (C=O). PMR spectrum (CDCl , ꢅ, ppm): 0.84 (6H, m, 6-CH , H-10), 1.02 (6H, m, H-1,
-CH ), 1.25 (8H, m, H-5, H-7ꢀH-9), 1.95 (1H, m, H-6), 2.40 (2H, m, H-4), 2.58 (1H, m, H-2). C NMR spectrum (CDCl3,
3
3
1
3
2
3
ꢅ, ppm): 14.14 (q, C-10), 16.97, 19.01 (both q, C-1, 2-CH ), 19.78 (q, 6-CH ), 23.02 (t, C-8), 29.28, 29.70, 31.68 (all t, C-5,
3
3
C-7, C-9), 39.04 (d, C-6), 40.29 (d, C-2), 41.20 (t, C-4), 206.60 (s, C-3).
Isopropyl-4S-methyloctanoate (8). A suspension of m-CPBA (4.10 g, 12.8 mmol) in anhydrous CHCl (30 mL) at
3
room temperature was treated dropwise with a solution of 7 (2.20 g, 12.0 mmol) in CHCl (9 mL); stirred for 48 h; diluted with
3
CH Cl (250 mL); washed successively with saturated solutions of NaHCO , Na S O , and NaCl; dried over MgSO ; and
2
2
3
2 2
3
4
2
0
ꢀ1
evaporated to afford 8 (2.44 g, 72%), [ꢆ] +4.13° (c 2.6, CHCl ). IR spectrum (KBr, ꢇ, cm ): 1740 (C=O). PMR spectrum
D
3
(
CDCl , ꢅ, ppm, J/Hz): 0.84 (3H, t, J = 6.0, H-8), 0.90 (3H, d, J = 6.0, 4-CH ), 1.19 [6H, d, J = 6.0, CH(CH ) ], 1.50 (9H, m,
3
3
3
2
1
3
H-3ꢀH-7), 2.25 (2H, m, H-2), 4.97 [1H, sept, J = 6.3, CH(CH ) ]. C NMR spectrum (CDCl , ꢅ, ppm): 19.10 (q, C-8), 21.03
3
2
3
(
q, 4-CH ), 21.67 [q, CH(CH ) ], 29.53 (d, C-4), 31.28, 31.85, 32.33, 35.22 (all t, C-3, C-5ꢀC-7), 62.73 (t, C-2), 67.61 [d,
3 3 2
CH(CH ) ], 173.30 (s, C-1).
3
2
1
-Bromo-3S-methylheptane (10). A solution of ester 8 (2.40 g, 12.0 mmol) and KOH (1.60 g, 29.0 mmol) in MeOH
(
10 mL) and H O (2 mL) was refluxed for 4 h and evaporated. The residue (1.85 g) was dissolved in H O (23 mL) and treated
2
2
with a solution of AgNO (2.04 g, 12.0 mmol) in hot water (8 mL, 60°C). The precipitate was filtered off and dried in vacuo
3
(
10–15 mm Hg) at 100°C to afford the silver salt (2.52 g) that was suspended in CCl (15 mL), stirred, treated dropwise with
4
a solution of Br (1.82 g, 11.5 mmol) in CCl (4 mL), held at room temperature for 2 h, and refluxed (until CO evolution
2
4
2
ceased). The precipitate was filtered off. The filtrate was evaporated. The residue was chromatographed (SiO , hexane) to
2
2
1
21
afford 10 (1.66 g, 83%), [ꢆ] +7.4° (c 3.7, CHCl ), cf. [ꢆ] +3.7° (c 3.3, CHCl ) (ee ~50%) [3]. The IR and PMR spectra
D
3
D
3
were identical to those published earlier [5].
1
4S-Methyloctadec-1-ene (11). A suspension of CuI (0.27 g, 1.21 mmol) in anhydrous THF (11 mL) was stirred,
treated with 2,2ꢃ-bipyridyl (0.18 g, 1.21 mmol), stirred for 0.5 h at 20°C under Ar, cooled to 2°C, treated with a solution of
bromide 10 (1.08 g, 5.6 mmol) in anhydrous THF (11 mL), stirred for 0.5 h, treated with a solution of Grignard reagent
prepared from Mg (0.25 g, 10.4 mg-at) and 10-undecenylbromide (1.96 g, 8.4 mmol) in anhydrous THF (20 mL), stirred for
2
h at 2°C and 16 h at room temperature, treated with saturated NH Cl solution (10 mL), stirred for 1 h at 10°C, and extracted
4
with Et O (3 ꢈ 50 mL). The extract was washed with saturated NaCl solution, dried over MgSO , and evaporated. The residue
2
4
was chromatographed (SiO , hexane) and evaporated to afford alkene 11 (0.84 g, 71%), bp 119–128°C (0.5 mm Hg),
2
2
3
ꢀ1
[
ꢆ] +1.2° (c 5.1, CHCl ). IR spectrum (ꢇ, cm ): 3080 (=CꢀH), 1640 (C=C), 1380 (CꢀCH ), 990, 970, 910 (C=C).
D
3
3
PMR spectrum (CDCl , ꢅ, ppm, J/Hz): 0.83 (3H, t, J = 6.5, H-18), 0.86 (3H, d, J = 6.5, 14-CH ), 1.00–1.50 (27H, br.s, CH ,
3
3
2
CH), 2.06 (2H, m, H-3), 4.97–5.84 (3H, m, H-1, H-2).
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2.
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G. Yu. Ishmuratov, M. P. Yakovleva, V. A. Vydrina, E. F. Khasanova, R. R. Muslukhov, N. M. Ishmuratova,
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