Synthesis of 4′-(2,6,6-trimethyl -2-cyclohexen-l-yl) -3'-buten-2'-ketoxime-N-O-alkyl ethers

Article abstract of DOI:10.3390/10080990

4′-(2,6,6-Trimethyl-2-cyclohexen-1-yl)-3′-buten-2′- ketoxime-N-O-alkyl ethers have been synthesized starting from α-ionone, separated into their E and Z isomers and characterized on the basis of ¹H-NMR and mass spectra.

Full text of DOI:10.3390/10080990

Molecules 2005, 10, 990–999
molecules
ISSN 1420-3049
http://www.mdpi.org
Synthesis of 4'-(2,6,6-Trimethyl -2-Cyclohexen-1-yl) -3'-Buten-
2'-Ketoxime-N-O-Alkyl Ethers
Tirthankar Banerjee and Prem Dureja*
Division of Agricultural Chemicals, Indian Agricultural Research Institute, New Delhi – 110 012 India
*Author to whom correspondence should be addressed; E-mail: Pd_dureja@yahoo.com
Received: 2 April 2004; in revised form: 23 April 2005 / Accepted: 25 April 2005 / Published: 31
August 2005
Abstract: 4'-(2,6,6-Trimethyl-2-cyclohexen-1-yl)-3'-buten-2'-ketoxime-N-O-alkyl ethers
have been synthesized starting from α-ionone, separated into their E and Z isomers and
characterized on the basis of 1H-NMR and mass spectra.
Keywords: α-Ionone, Condensation reaction.
Introduction
Interest in the oxime ether group of pesticides has grown considerably in recent years because of
their overall impact on the insect endocrine system. Among the oxime ether group of insect growth
regulators acetaldoxime ether showed high activity against M. domestica [1]. A variety of terpenoid
juvenile hormone (JH) analogues have been introduced [2] and some of them such as methoprene are
now in practical use for control of major insect pests. Most of the earlier JH analogues have terpenoid
or sesquiterpenoid structures [3]. A number of oxime ethers of terpenes are also known as insect
growth regulators [4]. Based on this observation, we report in this paper the synthesis of some oxime
ethers of α-ionone and their separation into the corresponding E and Z isomers.
Results and Discussion
4'-(2,6,6-Trimethyl-2-cyclohexen-1-yl)-3'-buten-2'-ketoxime needed for preparation of the
corresponding oxime N-O-alkyl ethers was obtained by reacting α-ionone with hydroxylamine
hydrochloride. It was identified based on its 1H-NMR spectrum. The oximes are usually obtained as a

Molecules 2005, 10
991
1:1 mixture of E and Z isomers inseparable by conventional chromatographic techniques. The 4’-
(2,6,6-trimethyl-2-cyclohexen-1-yl)-3'-buten-2'-ketoxime was then reacted with an appropriate alkyl
halide (Scheme I) to furnish the oxime ethers, which were separated into their geometric isomers by
column chromatography.
Scheme 1
O
N
OH
N
O
R
H2NOH
Ethanol
RBr
NaH, DMSO
4'-(2,6,6-trimethyl-2-
cyclohexen-1-yl)-3'-
buten-2'-one
4'-(2,6,6-trimethyl-2-
cyclohexen-1-yl)-3'-
buten-2'-ketoxime
4'-(2,6,6-trimethyl-2-cyclohexen
-1-yl)-3'-buten-2'-ketoxime-N-O
-alkyl ether
R = CH3, C2H5, C3H7, CH(CH3)2, C4H9, CH2CH(CH3)2, C5H11, C2H4CH(CH3)2, C6H13,
C7H15, C8H17 and C10H21.
The geometric isomers of the ketoximes are indicated by E and Z nomenclature used to designate
the geometrical relations of the groups around a double bond, taking the unshared pair of electrons at
the nitrogen atom at the lowest priority group. An unequivocal assignment of their stereochemistry
1
was accomplished by H–NMR. Under the reaction conditions shown in the Experimental, E-oximes
were the predominant products and the E/Z ratio calculated by GLC was ca. 2/1.
Formation of oxime ethers was characterized by the appearance of a two proton triplet at δ 4.08 -
1
4.12 due to O-CH2 (j) with a coupling constant (J) value of 3 Hz. The values assigned by H-NMR to
each proton in the Εand Z isomers of 4'-(2,6,6- trimethyl-2-cyclohexen-1-yl)-3'-buten-2'-ketoxime-N-
O-propyl ether (3) are given in Table 1 as a specific example. Product I showed two three proton
singlets at δ 0.94 and 0.92 due to CH3 (e) and CH3 (f), whereas in product II one six proton singlet was
observed downfield at δ 1.26 for CH3 (e) and CH3 (f). Similarly, a one proton doublet was found at δ
6.10 due to =CH (h) in the I isomer, but was found downfield at δ 6.75 in the case of the II product.
The difference in the chemical shifts of the methyl protons in the I and II products is due to different
anisotropic shielding in the isomers with their fixed geometries [5]. The presence of signals due to CH3
(e), CH3 (f) and =CH (h) upfield in the product I as compared to the II one indicated that the O-propyl
group is syn to the methyl group (i) in the product I, whereas it is anti to this methyl group (i) in the
1
product II (Table 1). Thus based on the H–NMR data, product I was assigned as the E configuration
and product II as the Z configuration

Molecules 2005, 10
992
1
Table 1. H-NMR of spectral data of the E and Z isomers of 4'-(2,6,6- trimethyl-2-
cyclohexen-1-yl)-3'-buten-2'-ketoxime-N-O-propyl ether
j
k
j
l
k
l
CH3CH2CH2
O
O
CH2CH2CH3
N
e
N
e
f
g
f
g
m
m
d
c
i
d
c
i
h
h
a
a
b
b
3(I)
3(II)
δ (ppm)
Isomer
3(I)
a
b
c
d
e
f
g
h
i
j
k
l
m
1.57 5.43 1.57 1.57 0.94 0.92 5.83 6.10 1.94 4.12 2.02 0.90 2.23
3(II) 1.58 5.45 1.58 1.58 1.26 1.26 5.90 6.75 1.97 4.08 2.01 0.91 2.00
Both products showed the same molecular ion peak (M+= 249) indicating that they are isomeric. A
distinct difference in the percent relative abundance with respect to the base peak has been observed in
the products I and II, which showed base peaks at m/z 134 and 83, respectively. Thus on the basis of
1
combined H-NMR and mass spectroscopy data, products 3(I) and 3(II) were characterized as 4'-
(2,6,6-trimethyl-2-cyclohexen-1-yl)-3'-buten-2'(E)-ketoxime-N-O-propyl ether and 4’-(2,6,6-trimethyl-
2-cyclohexen-1-yl)-3'-buten-2'(Z)-ketoxime-N-O-propyl ether, respectively. The 2’ stereochemistry
was similarly assigned for the other ketoxime –N-O-alkyl ethers. The 1H-NMR and mass spectra of the
other oxime ethers are given in Table 2.
Experimental
General
α-Ionone required for the study was procured from Fluka Chemika. Different alkyl halides, sodium
hydride and hydroxylamine hydrochloride were procured locally and used without further purification.
Thin Layer Chromatography (TLC) was performed on 20 x 20 cm2 glass plates coated with 0.5 mm
silica gel G, containing 10 per cent gypsum (as binder) and pre-activated at 120°C. The plates were
developed in a suitable solvent system [hexane-acetone (90:10 or 80:20)] and visualized by iodine
vapors. Isomers were separated by column chromatography using a glass column (75 cm x 2 cm i.d.)
containing 50g 60 – 120 mesh pre-activated silica gel slurried in hexane and eluting with hexane and
hexane and chloroform in different ratios. Different fractions (25 mL) were collected and distilled on a
water bath. The fraction containing the same products (as monitored by TLC) were combined and
purified further. Ratio of E and Z isomers was analyzed with a gas liquid chromatograph (GLC)
(Hewlett Packard Model 5890, Series II gas liquid chromatograph, equipped with a flame ionization

Molecules 2005, 10
993
detector and a capillary column [HP-1, methyl silicone gum, 10 m x 0.53 mm i.d. and 2.65 mm film
thickness], coupled with a Hewlett Packard 3390A integrator). The operating conditions were as
follows: oven, injector and detector temperatures at 150, 250 and 250°C, respectively. Nitrogen was
used as a carrier gas with a flow rate of 20 mL min-1. The proton nuclear magnetic resonance spectra
(1H-NMR) were recorded on a Varian EM 360 L (60 MHz) and on a Bruker 300 AC (300 MHz)
instrument. The solvents used were carbon tetrachloride (CCl4) and deuteriochloroform (CDCl3)
containing tetramethylsilane ((CH3)4Si, TMS) as the internal standard. The chemical shifts are
expressed in δ values (ppm) and coupling constant (J) are given in hertz (Hz). Mass spectra were
recorded on a HRGC - MEGA 2 series gas chromatograph coupled to a FISONS - TRIO 1000 ion trap
mass spectrometer and connected to a Panasonic KX - P1150 multi-mode printer. The ionization
potential was 70 eV.
4'-(2,6,6-Trimethyl-2-cyclohexen-1-yl)-3'-buten-2'-ketoxime: Hydroxylamine hydrochloride (0.75 g,
0.011 mole) was added to a stirred solution of α-ionone (1.9g, 0.01 mole) dissolved in dry and distilled
ethyl alcohol (25 mL) (see Scheme 1). Stirring was continued for another 2 h with simultaneous
monitoring by TLC (solvent system: hexane-acetone 80:20, Rf = 0.33). After completion of the
reaction, the reaction mixture was poured into water and extracted with diethyl ether (3 x 25 mL). The
combined diethyl ether extracts were washed with water, dried over anhydrous sodium sulphate, and
concentrated in vacuo, which produced an amber colored oily liquid, which was used directly in
subsequent reactions.
General Procedure for Preparation of 4'-(2,6,6-Trimethyl-2-cyclohexen-1-yl)-3'-buten-2'-ketoxime-N-
O-alkyl ethers:
Dimethyl sulfoxide (dried over molecular sieves, 5mL) was slowly added with stirring to sodium
hydride (0.024 g, 0.01mol, “weighed in a dry box”) in an atmosphere of dry nitrogen. The stirring was
continued further until the evolution of hydrogen ceased. To the above stirred solution, 4'-(2,6,6-
trimethyl-2-cyclohexen-1-yl)-3'-buten-2'-ketoxime (0.01 mole) was added dropwise maintaining the
temperature at 5°C (ice bath). The reaction mixture was stirred for another 1 hour, which was followed
by addition of the appropriate alkyl halide (0.011 mole), and stirring for another 2 hours. The progress
of the reaction was monitored by TLC (hexane-acetone, 90:10). After completion of the reaction, the
reaction mixture was poured into cold water and extracted with ethyl acetate (3 x 25 mL). The ethyl
acetate layer was separated, washed with water, dried over anhydrous sodium sulphate, and
concentrated in vacuo, which produced an oily residue. The oily residue was applied to a silica gel
column that then was eluted with hexane and hexane-chloroform (90:10), giving the corresponding E
and Z oxime O-ethers. Thus 12 different compounds were prepared using the above methods and
separated into their two isomers. The NMR and mass spectral data of these compounds are reported in
Table 2.

Molecules 2005, 10
994
1
Table 2. H-NMR and mass spectral data of 4'-(2,6,6-trimethyl-2-cyclohexen-1-yl)-3'-
buten-2'-ketoxime-N-O-alkyl ethers
O
R
O
R
N
e
N
e
f
g
f
g
m
m
d
c
i
d
c
i
h
h
a
a
b
b
I
II
Comp.
No.
R
Rf
(TLC)**
MS m/z (%)
1H-NMR (δ)
1(I)
CH3
0.61
6.04 (1H, h, d, J=8Hz), 5.81 (1H, g, dd, 221 (M+, 89), 203 (17), 207
J=3Hz), 5.43 (1H, b, s), 3.84 (2H, j, s), (4), 206 (5), 193 (89), 178
2.23 (1H, m, d, J =3Hz), 1.94 (3H, i, s), (48), 160 (8), 150 (49), 136
1.71 (1H, c2, q, J=3Hz), 1.58 (2H, d, t, (28), 134 (100), 119 (22),
J= 3Hz), 1.57 (3H, a, s), 1.42 (1H, c1, q, 117 (13), 107 (35), 105 (20),
J=3Hz), 0.94 (3H, e, s), 0.92 (3H, f, s).
93 (83), 91 (60), 85 (7), 83
(12), 79 (25), 77 (29).
1(II)
CH3
0.33
0.67
6.57 (1H, h, d, J=8 Hz) 5.79 (1H, g, dd, 221 (M+, 7), 207 (2), 193 (5),
J=3Hz ), 5.46 (1H, b, s), 3.87 (2H, j, s), 178 (4), 150 (5), 136 (3), 134
2.00 (1H, m, d, J =3 Hz), 1.97 (3H, i, s), (10), 119 (5), 117 (4), 107
1.71 (1H, c2, q, J=3 Hz), 1.58(2H, d, t, (5), 105 (3), 93 (17), 91 (14),
J=3 Hz), 1.58 (3H, a, s), 1.45 (1H, c1, q, 85 (92), 83 (100), 79 (5), 77
J=3 Hz), 1.26 (3H, e, s), 1.26 (3H, f, s).
(7).
2(I)
C2H5
6.11 (1H, h, d, J=8Hz), 5.85 (1H, g, dd, 235 (M+, 89), 217 (17), 207
J=3Hz), 5.42 (1H, b, s), 4.1 (2H, j, q, (4), 206 (5), 193 (89), 178
J=3Hz), 2.23 (1H, m, d, J=3Hz), 2.01 (48), 160 (8), 150 (49), 136
(3H, l, t, J=3Hz), 1.94 (3H, i, s), 1.71 (28), 134 (100), 119 (22),
(1H, c2, q, J= 3Hz), 1.58 (2H, d, t, 117 (13), 107 (35), 105 (20),
J=3Hz), 1.57 (3H, a, s), 1.42 (1H, c1, q, 93 (83), 91 (60), 85 (7), 83
J= 3Hz), 0.94 (3H, e, s), 0.92 (3H, f, s).
(12), 79 (25), 77 (29).
2(II)
C2H5
0.34
6.67 (1H, h, d, J=8 Hz) 5.83 (1H, g, dd, 235 (M+, 7), 207 (2), 193 (5),
J=3Hz ), 5.4 (1H, b, s), 4.08 (2H, j, q, 178 (4), 150 (5), 136 (3), 134
J=3 Hz), 2.06 (3H, l, t, J=3 Hz), 2.00 (10), 119 (5), 117 (4), 107
(1H, m, d, J=3 Hz), 1.97 (3H, i, s), 1.71 (5), 105 (3), 93 (17), 91 (14),
(1H, c2, q, J=3 Hz), 1.58 (2H, d, t, J=3 85 (92), 83 (100), 79 (5), 77
Hz), 1.58 (3H, a, s), 1.45 (1H, c1, q, J=3 (7).
Hz), 1.26 (3H, e, s), 1.26 (3H, f, s).

Molecules 2005, 10
995
Table 2. Cont.
3(I)
3(II)
4(I)
C3H7
0.75
0.39
0.75
6.10 (1H, h, d, J=8Hz), 5.83 (1H, g, dd, 249 (M+, 89), 234 (17), 207
J=3Hz), 5.43 (1H, b, s), 4.12 (2H, j, t, J= (4), 206 (5), 193 (89), 178
3Hz), 2.23 (1H, m, d, J=3Hz), 1.94 (3H, (48), 160 (8), 150 (49), 136
i, s), 2.02 (2H, k, m), 1.71(1H, c2, q, J= (28), 134 (100), 119 (22),
3Hz), 1.58 (2H, d, t, J=3Hz), 1.57 (3H, 117 (13), 107 (35), 105
a, s), 1.42 (1H, c1, q, J=3Hz), 0.94 (3H, (20), 93 (83), 91 (60), 85
e, s), 0.92 (3H, f, s), 0.90 (3H, l, t, J= (7), 83 (12), 79 (25), 77
3Hz).
(29).
C3H7
6.75 (1H, h, d, J=8 Hz) 5.90 (1H, g, dd, 249 (M+, 7), 207 (2), 193
J=3Hz ), 5.45 (1H, b, s), 4.08 (2H, j, t, (5), 178 (4), 150 (5), 136
J= 3 Hz), 2.01 (2H, k, m), 2.00 (1H, m, (3), 134 (10), 119 (5), 117
d, J=3 Hz), 1.97 (3H, i, s), 1.71 (1H, c2, (4), 107 (5), 105 (3), 93
q, J=3 Hz), 1.58 (2H, d, t, J=3 Hz), 1.58 (17), 91 (14), 85 (92), 83
(3H, a, s), 1.45 (1H, c1, q, J=3 Hz), 1.26 (100), 79 (5), 77 (7).
(3H, e, s), 1.26 (3H, f, s), 0.91 (3H, l, t,
J=3 Hz).
CH(CH3)2
6.19 (1H, h, d, J=8Hz), 5.83 (1H, g, dd, 249 (M+, 89), 234 (17), 207
J=3Hz), 5.43 (1H, b, s), 4.23 (2H, j, h, (4), 206 (5), 193 (89), 178
J= 3Hz), 2.23 (1H, m, d, J=3Hz), 2.02 (48), 160 (8), 150 (49), 136
(6H, l, d, J=3Hz), 1.94 (3H, i, s), 1.71 (28), 134 (100), 119 (22),
(1H, c2, q, J=3Hz), 1.58 (2H, d, t, 117 (13%), 107 (35), 105
J=3Hz), 1.57 (3H, a, s), 1.42 (1H, c1, q, (20), 93 (83), 91 (60), 85
J=3Hz), 0.94 (3H, e, s), 0.92 (3H, f, s).
(7), 83 (12), 79 (25), 77
(29).
4(II)
CH(CH3)2
0.39
6.83 (1H, h, d, J=8 Hz) 5.90 (1H, g, dd, 249 (M+, 7), 207 (2), 193
J=3Hz ), 5.45 (1H, b, s), 4.26 (2H, j, h, J (5), 178 (4), 150 (5), 136
=3 Hz), 2.03 (6H, l, d, J=3 Hz), 2.00 (3), 134 (10), 119 (5), 117
(1H, m, d, J=3 Hz), 1.97 (3H, i, s), (4), 107 (5), 105 (3), 93
1.71(1H, c2, q, J=3 Hz), 1.58(2H, d, t, J (17), 91 (14), 85 (92), 83
=3 Hz), 1.58 (3H, a, s), 1.45 (1H, c1, q, J (100), 79 (5), 77 (7).
=3 Hz), 1.26 (3H, e, s), 1.26 (3H, f, s),
5(I)
C4H9
0.76
6.16 (1H, h, d, J=8Hz), 5.84 (1H, g, dd, 263 (M+, 89), 248 (17), 207
J=3Hz), 5.4 (1H, b, s), 4.0 (2H, j, t, J= (4), 206 (5), 193 (89), 178
3Hz), 2.23 (1H, m, d, J=3Hz), 1.94 (3H, (48), 160 (8), 150 (49), 136
I, s), 2.02 (4H, k, m), 1.71 (1H, c2, q, J= (28), 134 (100), 119 (22),
3Hz), 1.58 (2H, d, t, J=3Hz), 1.57 (3H, 117 (13), 107 (35), 105
a, s), 1.42 (1H, c1, q, J=3Hz), 0.94 (3H, (20), 93 (83), 91 (60), 85
e, s), 0.92 (3H, f, s), 0.90 (3H, l, t, J= (7), 83 (12), 79 (25), 77
3Hz).
(29).

Molecules 2005, 10
996
Table 2. Cont.
5(II)
C4H9
CH2CH(CH3)2
CH2CH(CH3)2
C5H11
0.41
0.76
0.44
0.83
0.47
6.83 (1H, h, d, J=8 Hz) 5.68 (1H, g, dd, 263 (M+, 7), 207 (2), 193
J=3Hz ), 5.37 (1H, b, s), 4.12 (2H, j, t, J (5), 178 (4), 150 (5), 136
=3 Hz), 2.01 (4H, k, m), 2.00 (1H, m, d, (3), 134 (10), 119 (5), 117
J=3 Hz), 1.97 (3H, I, s), 1.71 (1H, c2, q, (4), 107 (5), 105 (3), 93
J=3 Hz), 1.58 (2H, d, t, J=3 Hz), 1.58 (17), 91 (14), 85 (92), 83
(3H, a, s), 1.45 (1H, c1, q, J=3 Hz), 1.26 (100), 79 (5), 77 (7).
(3H, e, s), 1.26 (3H, f, s), 0.91 (3H, l, t, J
=3 Hz).
6(I)
6.10 (1H, h, d, J = 8Hz), 5.87 (1H, g, dd, 263 (M+, 89), 248 (17), 207
J=3Hz), 5.4 (1H, b, s), 3.8 (2H, j, d, J= (4), 206 (5), 193 (89), 178
3Hz), 2.23 (1H, m, d, J=3Hz), 1.94 (3H, (48), 160 (8), 150 (49), 136
I, s), 2.02 (1H, k, m), 1.71 (1H, c2, q, J= (28), 134 (100), 119 (22),
3Hz), 1.58 (2H, d, t, J=3Hz), 1.57 (3H, 117 (13), 107 (35), 105
a, s), 1.42(1H, c1, q, J=3Hz), 0.94(3H, e, (20), 93 (83), 91 (60), 85
s), 0.92(3H, f, s), 0.90 (6H, l, d, J= 3Hz). (7), 83 (12), 79 (25), 77
(29).
6.8 (1H, h, d, J=8 Hz) 5.90 (1H, g, dd, J 263 (M+, 7%), 207 (2%),
=3Hz ), 5.45 (1H, b, s), 3.84 (2H, j, d, J 193 (5%), 178 (4%), 150
=3 Hz), 2.01 (1H, k, m), 2.00 (1H, m, d, (5%), 136 (3%), 134 (10%),
J=3 Hz), 1.97 (3H, i, s), 1.71 (1H, c2, q, 119 (5%), 117 (4%), 107
J=3 Hz), 1.58(2H, d, t, J=3 Hz), 1.58 (5%), 105 (3%), 93 (17%),
(3H, a, s), 1.45 (1H, c1, q, J=3 Hz), 1.26 91 (14%), 85 (92%), 83
(3H, e, s), 1.26 (3H, f, s), 0.91 (6H, l, d, (100%), 79 (5%), 77 (7%).
J=3 Hz).
6.23 (1H, h, d, J=8Hz), 5.84 (1H, g, dd, 277 (M+, 89), 262 (17), 207
J=3Hz), 5.42 (1H, b, s), 4.0 (2H, j, t, J= (4), 206 (5), 193 (89), 178
3Hz), 2.23 (1H, m, d, J=3Hz), 1.94 (3H, (48), 160 (8), 150 (49), 136
i, s), 2.02 (6H, k, m), 1.71 (1H, c2, q, J= (28), 134 (100), 119 (22),
3Hz), 1.58 (2H, d, t, J =3Hz), 1.57 (3H, 117 (13), 107 (35), 105
a, s), 1.42 (1H, c1, q, J=3Hz), 0.94 (3H, (20), 93 (83), 91 (60), 85
e, s), 0.92 (3H, f, s), 0.90 (3H, l, t, (7), 83 (12), 79 (25), 77
6(II)
7(I)
J=3Hz).
(29).
7(II)
C5H11
6.96 (1H, h, d, J=8 Hz) 5.72 (1H, g, dd, 277 (M+, 7), 207 (2), 193
J=3Hz ), 5.39 (1H, b, s), 4.08 (2H, j, t, J (5), 178 (4), 150 (5), 136
=3 Hz), 2.01 (6H, k, m), 2.00 (1H, m, d, (3), 134 (10), 119 (5), 117
J=3 Hz), 1.97 (3H, i, s), 1.71 (1H, c2, q, J (4), 107 (5), 105 (3), 93
=3 Hz), 1.58 (2H, d, t, J=3 Hz), 1.58 (17), 91 (14), 85 (92), 83
(3H, a, s), 1.45 (1H, c1, q, J=3 Hz), 1.26 (100), 79 (5), 77 (7).
(3H, e, s), 1.26 (3H, f, s), 0.91 (3H, l, t,
J=3 Hz).

Molecules 2005, 10
997
Table 2. Cont.
8(I)
C2H4CH(CH3)2
0.83
0.47
0.86
0.54
0.86
6.23 (1H, h, d, J=8Hz), 5.84 (1H, g, dd, 277 (M+, 89), 262 (17), 207
J=3Hz), 5.42 (1H, b, s), 4.0 (2H, j, t, (4), 206 (5), 193 (89), 178
J=3Hz), 2.23 (1H, m, d, J=3Hz), 1.94 (48), 160 (8), 150 (49), 136
(3H, i, s), 2.02 (3H, k, m), 1.71 (1H, c2, (28), 134 (100), 119 (22),
q, J=3Hz), 1.58(2H, d, t, J= 3Hz), 1.57 117 (13), 107 (35), 105
(3H, a, s), 1.42 (1H, c1, q, J=3Hz), 0.94 (20), 93 (83), 91 (60), 85
(3H, e, s), 0.92 (3H, f, s), 0.90 (6H, l, d, (7), 83 (12%), 79 (25), 77
J=3Hz).
(29).
8(II)
C2H4CH(CH3)2
6.96 (1H, h, d, J=8 Hz) 5.72 (1H, g, dd, 277 (M+, 7), 207 (2), 193
J=3Hz ), 5.39 (1H, b, s), 4.08 (2H, j, t, (5), 178 (4), 150 (5), 136
J=3 Hz), 2.01 (3H, k, m), 2.00 (1H, m, (3), 134 (10), 119 (5), 117
d, J=3 Hz), 1.97 (3H, i, s), 1.71 (1H, c2, (4), 107 (5), 105 (3), 93
q, J=3 Hz), 1.58 (2H, d, t, J=3 Hz), 1.58 (17), 91 (14), 85 (92), 83
(3H, a, s), 1.45 (1H, c1, q, J=3 Hz), 1.26 (100%), 79 (5), 77 (7).
(3H, e, s), 1.26 (3H, f, s), 0.91 (6H, l, d,
J=3 Hz).
9(I)
C6H13
6.13 (1H, h, d, J=8Hz), 5.78 (1H, g, dd, 291 (M+, 89), 276 (17), 207
J=3Hz), 5.43 (1H, b, s), 4.0 (2H, j, t, J= (4), 206 (5), 193 (89), 178
3Hz), 2.23 (1H, m, d, J=3Hz), 1.94 (3H, (48), 160 (8), 150 (49), 136
i, s), 2.02 (8H, k, m), 1.71 (1H, c2, q, J= (28), 134 (100), 119 (22),
3Hz), 1.58 (2H, d, t, J=3Hz), 1.57 (3H, 117 (13), 107 (35), 105
a, s), 1.42 (1H, c1, q, J=3Hz), 0.94 (3H, (20), 93 (83), 91 (60), 85
e, s), 0.92 (3H, f, s), 0.90 (3H, l, t, J= (7), 83 (12), 79 (25), 77
3Hz).
(29).
9(II)
C6H13
6.65 (1H, h, d, J=8 Hz) 5.90 (1H, g, dd, 291 (M+, 7), 207 (2), 193
J=3Hz ), 5.45 (1H, b, s), 4.08 (2H, j, t, J (5), 178 (4), 150 (5), 136
=3 Hz), 2.01 (8H, k, m), 2.00 (1H, m, d, (3), 134 (10), 119 (5), 117
J=3 Hz), 1.97 (3H, i, s), 1.71 (1H, c2, q, (4), 107 (5), 105 (3), 93
J=3 Hz), 1.58 (2H, d, t, J=3 Hz), 1.58 (17), 91 (14), 85 (92), 83
(3H, a, s), 1.45 (1H, c1, q, J=3 Hz), 1.26 (100), 79 (5), 77 (7).
(3H, e, s), 1.26 (3H, f, s), 0.91 (3H, l, t, J
=3 Hz).
10(I)
C7H15
6.10 (1H, h, d, J=8Hz), 5.87 (1H, g, dd,
J=3Hz), 5.43 (1H, b, s), 4.0 (2H, j, t, J=
305 (M+, 89), 290 (17), 207
(4), 206 (5), 193 (89), 178
3Hz), 2.23 (1H, m, d, J=3Hz), 1.94 (3H, (48), 160 (8), 150 (49), 136
i, s), 2.02 (10H, k, m), 1.71 (1H, c2, q, J (28), 134 (100), 119 (22),
=3Hz), 1.58 (2H, d, t, J=3Hz), 1.57 (3H, 117 (13), 107 (35), 105
a, s), 1.42 (1H, c1, q, J=3Hz), 0.94 (3H,
e, s), 0.92 (3H, f, s), 0.90 (3H, l, t, J=3
Hz).
(20), 93 (83), 91 (60), 85
(7), 83 (12), 79 (25), 77
(29).

Molecules 2005, 10
998
Table 2. Cont.
10(II) C7H15
0.56
0.87
0.57
0.88
0.60
6.81 (1H, h, d, J=8 Hz) 5.90 (1H, g, dd, 305 (M+, 7), 207 (2), 193
J=3Hz ), 5.4 (1H, b, s), 4.0 (2H, j, t, J=3 (5), 178 (4), 150 (5), 136
Hz), 2.01 (10H, k, m), 2.00 (1H, m, d, J (3), 134 (10), 119 (5), 117
=3 Hz), 1.97 (3H, i, s), 1.71 (1H, c2, q, J (4), 107 (5), 105 (3), 93
=3 Hz), 1.58 (2H, d, t, J=3 Hz), 1.58 (17), 91 (14), 85 (92), 83
(3H, a, s), 1.45 (1H, c1, q, J=3 Hz), 1.26 (100), 79 (5), 77 (7).
(3H, e, s), 1.26 (3H, f, s), 0.91 (3H, l, t, J
=3 Hz).
11(I)
C8H17
6.16 (1H, h, d, J=8 Hz), 5.80 (1H, g, dd, 319 (M+, 89), 304 (17), 207
J=3 Hz), 5.43 (1H, b, s), 4.0 (2H, j, t, J= (4), 206 (5), 193 (89), 178
3 Hz), 2.23 (1H, m, d, J=3Hz), 1.94 (3H, (48), 160 (8), 150 (49), 136
i, s), 2.02 (12H, k, m), 1.71 (1H, c2, q, J
=3 Hz), 1.58 (2H, d, t, J=3 Hz), 1.57
(28), 134 (100), 119 (22),
117 (13), 107 (35), 105
(3H, a, s), 1.42 (1H, c1, q, J=3 Hz), 0.94 (20), 93 (83), 91 (60), 85
(3H, e, s), 0.92 (3H, f, s), 0.90 (3H, l, t, J (7), 83 (12), 79 (25), 77
=3 Hz).
(29).
11(II) C8H17
6.75 (1H, h, d, J=8 Hz) 5.73 (1H, g, dd, 319 (M+, 7), 207 (2), 193
J=3Hz ), 5.4 (1H, b, s), 4.0 (2H, j, t, J=3 (5), 178 (4), 150 (5), 136
Hz), 2.01 (12H, k, m), 2.00 (1H, m, d, J (3), 134 (10), 119 (5), 117
=3 Hz), 1.97 (3H, i, s), 1.71 (1H, c2, q, J (4), 107 (5), 105 (3), 93
=3 Hz), 1.58 (2H, d, t, J=3 Hz), 1.58 (17), 91 (14), 85 (92), 83
(3H, a, s), 1.45 (1H, c1, q, J=3 Hz), 1.26 (100), 79 (5), 77 (7).
(3H, e, s), 1.26 (3H, f, s), 0.91 (3H, l, t, J
=3 Hz).
12(I)
C10H21
6.13 (1H, h, d, J=8 Hz), 5.87 (1H, g, dd, 347 (M+, 89), 332 (17), 207
J=3 Hz), 5.5 (1H, b, s), 4.0 (2H, j, t, J= 3 (4), 206 (5), 193 (89), 178
Hz), 2.23 (1H, m, d, J=3 Hz), 1.94 (3H,
i, s), 2.02 (16H, k, m), 1.71 (1H, c2, q, J
=3 Hz), 1.58 (2H, d, t, J=3 Hz), 1.57
(48), 160 (8), 150 (49), 136
(28), 134 (100), 119 (22),
117 (13), 107 (35), 105
(3H, a, s), 1.42 (1H, c1, q, J=3 Hz), 0.94 (20), 93 (83), 91 (60), 85
(3H, e, s), 0.92 (3H, f, s), 0.90 (3H, l, t,
(7), 83 (12), 79 (25), 77
(29).
J=3 Hz).
12(II) C10H21
7.0 (1H, h, d, J=8 Hz) 5.8 (1H, g, dd, J= 347 (M+, 7), 207 (2), 193
3 Hz), 5.45 (1H, b, s), 4.0 (2H, j, t, J=3 (5), 178 (4), 150 (5), 136
Hz), 2.01 (16H, k, m), 2.00 (1H, m, d, J (3), 134 (10), 119 (5), 117
=3 Hz), 1.97 (3H, i, s), 1.71 (1H, c2, q, J (4), 107 (5), 105 (3), 93
=3 Hz), 1.58(2H, d, t, J=3 Hz), 1.58 (3H, (17), 91 (14), 85 (92), 83
a, s), 1.45 (1H, c1, q, J=3 Hz), 1.26 (3H, (100), 79 (5), 77 (7).
e, s), 1.26 (3H, f, s), 0.91 (3H, l, t, J=3
Hz).
* TLC solvent system hexane-acetone 90 : 10.

Molecules 2005, 10
999
References
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of potent insect growth regulators with juvenile hormone activity. J. Agric. Food. Chem. 1973,
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2. Wigglesworth, V. B. Insect Hormones; W.H. Freeman: San Francisco, 1970; pp 1-159.
3. Bowers, W.S. In Naturally Occurring Insecticides; Jacobson, M.; Crosby, D. G., Eds.; Marcel
Dekker: New York, 1971; p. 307.
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Pesticide Res. Jour. 1995, 7, 128-131.
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Sample availability: Available on request from the corresponding author.
© 2005 by MDPI (http://www.mdpi.org). Reproduction is permitted for noncommercial purposes.