Liquid-phase noncatalytic oxidation of monoterpenoids with nitrous oxide

Article abstract of DOI:10.1007/s11172-007-0187-9

A series of monoterpenoids differing in the number of double bonds and the pattern of their substitution were tested in the liquid-phase noncatalytic oxidation with nitrous oxide (N₂O). The structure of olefins has a significant effect on the oxidation route. In the case of terpenoids containing 1,1-disubstituted double bond, nor-carbonyl compounds are formed with high selectivity.

Full text of DOI:10.1007/s11172-007-0187-9

Russian Chemical Bulletin, International Edition, Vol. 56, No. 6, pp. 1239—1243, June, 2007
1239
Liquidꢀphase noncatalytic oxidation of monoterpenoids
with nitrous oxide*
E. P. Romanenko,a E. V. Starokon´,b G. I. Panov,b and A. V. Tkacheva,c
ꢀ
аN. N. Vorozhtsov Novosibirsk Institute of Organic Chemistry,
Siberian Branch of the Russian Academy of Sciences,
9 prosp. Akad. Lavrent´eva, 630090 Novosibirsk, Russian Federation.
Fax: +7 (383) 330 9752. Eꢀmail: atkachev@nioch.nsc.ru
bG. K. Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences,
5 prosp. Akad. Lavrent´eva, 630090 Novosibirsk, Russian Federation.
Fax: +7 (383) 330 8056
cNovosibirsk State University,
2 ul. Pirogova, 630090 Novosibirsk, Russian Federation.
Fax: +7 (383) 330 9752
A series of monoterpenoids differing in the number of double bonds and the pattern of their
substitution were tested in the liquidꢀphase noncatalytic oxidation with nitrous oxide (N2O).
The structure of olefins has a significant effect on the oxidation route. In the case of terpenoids
containing 1,1ꢀdisubstituted double bond, norꢀcarbonyl compounds are formed with high
selectivity.
Key words: nitrous oxide, alkene oxidation, monoterpenes.
In recent years, nitrous oxide (nitrogen(I) oxide, N2O)
has provoked ever increasing interest of researchers as an
effective oxygen donor in selective oxidation of many
organic compounds both in the liquid and gas phases.
Catalyzed direct oxidation of benzene to phenol,1 epoxiꢀ
dation of alkenes,2 and oxidation of alcohols3 are exꢀ
amples of using N2O as an oxidant. However, the ability
of nitrous oxide to accomplish liquidꢀphase noncatalytic
oxidation of alkenes, resulting in selective formation of
carbonyl compounds, is probably most intriguing.4 This
method is obviously attractive for oxidative functionaliꢀ
zation of olefins, components of basic hydrocarbon raw
materials, in particular, isoprenoids.
Quite a few examples of successful nitrous oxide oxiꢀ
dation of acyclic, carboꢀ and heterocyclic alkenes,4,5 and
unsaturated polymers6 are known to date. In order to
extend the range of possible synthetic applications of this
reaction, we studied the oxidation behavior of terpene
type olefins, which give diverse practically valuable prodꢀ
ucts of oxidation.
and positions of double bonds, viz., βꢀpinene (1), liꢀ
monene (2), carvone (3), 3ꢀcarene (4), 2ꢀcarene (5), and
dehydrolinalool (6), in the liquidꢀphase oxidation with
nitrous oxide.
The oxidation was carried out for 12 h at 250 °C in a
substrate—benzene—N2O system (50—70 atm). The maꢀ
jor reaction products were identified using GC/MS analyꢀ
sis by comparing their full mass spectra and retention
indexes with the same data for reference compounds. In
some cases, the products were isolated using column liqꢀ
uid and preparative gas liquid chromatography, and the
molecular structures of the products were subsequently
determined using NMR and IR spectroscopy and mass
spectrometry data. The results of nitrous oxide oxidation
experiments of olefins 1—6 are summarized in Table 1.
βꢀPinene (1) containing one exocyclic double bond
in the molecule undergoes destructive oxidation with
a 83% selectivity to give a norꢀcarbonyl compound,
nopinone (7) (Scheme 1). The second oxidation product,
cisꢀdihydromyrtenal (8), is present in the mixture only in
minor amounts (6% of the total reaction products).
The limonene molecule (2) contains two double bonds,
each being able to react with N2O. However, the different
degrees of substitution at the double bonds suggest that
their abilities to react with N2O would also differ. Indeed,
4ꢀacetylꢀ1ꢀmethylcyclohexene (9) resulting from destrucꢀ
tive oxidation of the isopropenyl double bond is the preꢀ
Results and Discussion
This study deals with the behavior of unsaturated
monoterpene hydrocarbons, differing in the number
* Dedicated to the memory of Academician N. N. Vorozhtsov
on the 100th anniversary of his birth.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1193—1197, June, 2007.
1066ꢀ5285/07/5606ꢀ1239 © 2007 Springer Science+Business Media, Inc.

1240
Russ.Chem.Bull., Int.Ed., Vol. 56, No. 6, June, 2007
Romanenko et al.
Table 1. Results of oxidation experiments of monoterpenoids
1—6 with nitrous oxide
and 11″, respectively), are found in the mixture but their
total amount does not exceed 5% (Scheme 2).
In the case of carvone (3), the selectivity of the oxidaꢀ
tive process was even higher, the endocyclic double bond
remaining totally intact, the reaction involving excluꢀ
sively the isopropenyl double bond to give diketone 12
(Scheme 3). This is consistent with the results on the
oxidation of model dienes, indicating a substantial deacꢀ
tivating effect of the carbonyl group on the reactivity of
the double carbon—carbon bond conjugated with this
group.5
Subꢀ
strate
Converꢀ
sion (%)
Product distribution
according to GLC (%)
1
2
19.1
72.8
82.7 (7), 5.8 (8)
52.3 (9), 6.7 (10), 1.8 (11´), 2.5 (11″),
13.0*
3
4
57.6
22.1
64.9 (12), 35.1 (13)
10.4 (14´), 17.6 (14″), 31.0 (15),
8.1 (17a), 21.7 (17b), 2.7 (18)
24.0 (20), 18.5 (21), 8.7 (22)
14.4**
5 → 19
6 → 23
72.8
54.8
16.1 (26), 31.2 (27), 35.2 (28)
Scheme 3
* Total cyclopropanation products.
** Cyclopropanation product.
Scheme 1
Apart from oxidation product 12, the oxidation of
carvone (3) affords homoꢀderivative 13 (yield 35%), reꢀ
sulting from cyclopropanation of the double carbon—carꢀ
bon bond in the isopropenyl group. Cyclopropane
homoꢀderivatives are formed through the addition of the
methylene (carbene), liberated upon destructive oxidaꢀ
tion of the terminal double bond, to the double bond of
the initial substrate.5 The products of methylene addition
to the double bond were also found for other substrates,
but in most cases, benzene used as the solvent was the
main carbene acceptor, being converted into cycloꢀ
heptatriene. In particular, oxidation of olefins 2 and 5
gives compounds identified, on the basis of their mass
spectra, as homoꢀderivatives formed upon cycloproꢀ
panation.
dominant component of the product mixture formed from
limonene (52% of the total reaction products). As in the
case of βꢀpinene, the product of oxidation of 1,1ꢀdisubꢀ
stituted double bond with retention of the carbon skeleton,
aldehyde 10 (a mixture of two diastereomers), is formed
in a considerably lower amount (7% of the total reaction
products) than the norꢀcarbonyl compound. The prodꢀ
ucts resulting from oxidation of the endocyclic double
bond, namely, cisꢀ and transꢀdihydrocarvones (11´
Scheme 2
The degree of conversion of 3ꢀcarene (4) under these
reaction conditions was only ~20%, which is in line with
the low reactivity of the trisubstituted double bond alꢀ
ready observed for limonene. In addition to the diaꢀ
stereomeric caranꢀ4ꢀones (14´ and 14″), resulting from
double bond oxidation with retention of the core of initial
olefin 4, the reaction gave acyclic ketone 15 (Scheme 4).
The most probable pathway to compound 15 is double
bond cleavage in the substrate to give a monocyclic unꢀ
saturated ketone 16, which undergoes thermal 1,5ꢀhomoꢀ
dienyl hydrogen atom shift, typical of vinylcyclopropanes.7
The double bond configuration in product 15 is deterꢀ
mined by the positions of substituents in the cycloproꢀ
pane ring in the transition state of the sigmatropic rearꢀ
rangement.
Apart from carbonyl compounds 14 and 15, the mixꢀ
ture contains mꢀ and pꢀcymols (17a,b) and 3,7,7ꢀtriꢀ
R1 = H, R2 = Me (11´); R1 = Me, R2 = H (11″)

Nitrous oxide oxidation of monoterpenoids
Russ.Chem.Bull., Int.Ed., Vol. 56, No. 6, June, 2007
1241
Scheme 4
R1 = H, R2 = Me (14´); R1 = Me, R2 = H (14″)
Scheme 5
methylꢀ1,3,5ꢀcycloheptatriene (18) resulting from oxidaꢀ
tive dehydrogenation of 3ꢀcarene.
2ꢀCarene (5) is isomerized at the reaction temperaꢀ
ture to transꢀisolimonene (19).8 Although the accessibilꢀ
ity of the endocyclic double bond in diene 19 is somewhat
higher than in limonene (2), the products of oxidation
of the isopropenyl double bond, carbonyl compounds
20—22, are still the major reaction products (Scheme 5).
Like 2ꢀcarene, dehydrolinalool (6) cannot withstand
the drastic reaction conditions: at 250 °C, the starting
monoterpenoid undergoes carbocyclization to give cyclic
dienol 23 as a mixture of two diastereomers.9 Presumably,
oxidation of dienol 23 affords carbonyl compounds 24
and 25. However, these compounds are missing from the
product mixture, the reaction giving unsaturated keto
alcohols 26 and 27 (yields 16 and 31%), resulting from
the sigmatropic rearrangement of the enol form of 24
and 25 (Scheme 6). Comparison of the heats of formation
Scheme 6

1242
Russ.Chem.Bull., Int.Ed., Vol. 56, No. 6, June, 2007
Romanenko et al.
with AcOEt concentration gradient from 0 to 50% or a hexꢀ
ane—CH2Cl2 mixture with CH2Cl2 concentration gradient from
0 to 100%) and preparative gas chromatography (a 4.5 m × 6 mm
column, 15% OVꢀ101/NꢀAWꢀDMCS; nitrogen as a carrier gas,
60 mL min–1; column temperature 150 °C).
of compounds 24—27 estimated by AM1 and PM3 calcuꢀ
lations attests to higher thermodynamic stability of keꢀ
tones 26 and 27 with respect to their isomers. Unsaturated
keto alcohol 28, formed probably upon migration of the
methyl group in isomer 27, is formed in 35% yield.
5RꢀAcetylꢀ2ꢀmethylꢀ2ꢀcyclohexenꢀ1ꢀone (12). Rf 0.22
(CH2Cl2), [α]19
–13 (c 6.67, CHCl3). The NMR and mass
578
spectra agree with published data.11
Experimental
2ꢀMethylꢀ5Rꢀ(1ꢀmethylcyclopropyl)cyclohexꢀ2ꢀenꢀ1ꢀone
Commercial (–)ꢀβꢀpinene (>99%, Fluka), (R)ꢀ(+)ꢀliꢀ
monene (97%, Aldrich), (L)ꢀ(–)ꢀcarvone (99%, Acros), and
(+)ꢀ2ꢀcarene (97%, Aldrich) were used. (+)ꢀ3ꢀCarene with
[α]D +16.0 (d4 0.863) was obtained by distillation of comꢀ
mon pine (Pinus silvestris) needle oil, racemic dehydrolinalool
was prepared by condensation of acetylene with 6ꢀmethylꢀ5ꢀ
heptenꢀ2ꢀone. Medical nitrous oxide (99.8%) produced by the
Cherepovets plant Azot was used as the oxidant. All solvents
were freshly distilled prior to use.
(13). Rf 0.44 (CH2Cl2), [α]19
+8.9 (c 4.27, CHCl3). The
578
1H NMR spectrum coincides with published data.12 13C NMR
(CDCl3), δ: 199.2 (s, C(1)); 144.1 (d, C(3)); 135.7 (s, C(2));
44.3 (d, C(5)); 42.1 (t, C(6)); 29.6 (t, C(4)); 19.2 (q, C(9)); 18.5
(s, C(8)); 15.9 (q, C(7)); 12.5, 12.6 (both t, C(10), C(11)). MS,
m/z (Irel (%)): 164 [M]+ (6), 136 (38), 122 (25), 121 (15), 109
(51), 108 (61), 107 (38), 106 (15), 95 (35), 94 (16), 93 (65), 91
(19), 82 (100), 81 (78), 80 (12), 79 (42), 77 (16), 72 (17), 67
(20), 55 (14), 54 (35), 53 (24), 41 (25), 39 (27).
20
20
GC/MS analysis of reaction mixtures was performed on a
HewlettꢀPackard G1081A instrument consisting of an HP 5890
gas chromatograph, series II, and an HP MSD 5971 mass
selective detector; ionizing electron energy 70 eV; an
HР5 column (5% diphenyl, 95% dimethylsiloxane),
30 m × 0.25 mm × 0.25 µm; helium as the carrier gas,
1 mL min–1; column temperature programming mode: 2 min at
50 °C, heating at 10 °C min–1, and 5 min at 280 °C; temperature
of the ion source 173 °C; data collection rate 1.2 scan s–1 in the
mass range of 30—650 amu. The components of mixtures were
identified by comparing their full mass spectra and retention
indexes with the corresponding data for reference compounds.10
The contents of the components in the mixture were calculated
from the peak areas without correction factors.
5,5ꢀDimethyloctaꢀ3E,6Zꢀdienꢀ2ꢀone (15). Rf 0.66 (hexꢀ
ane—AcOEt, 2 : 1 v/v). 1H NMR (CDCl3), δ: 1.21 (s, 6 H,
CMe2); 1.57 (dd, 3 H, C(8)H3, J8,7 = 7.0 Hz, J8,6 = 1.1 Hz);
2.24 (s, 3 H, C(1)H3); 5.33 (dq, 1 H, H(6), J6,7 = 11.3 Hz, J6,8
=
1.1 Hz); 5.43 (dq, 1 H, H(7), J7,6 = 11.3 Hz, J7,8 = 7.0 Hz); 6.04
(d, 1 H, H(3), J3,4 = 16.2 Hz); 6.88 (d, 1 H, H(4), J4,3 = 16.2 Hz).
13C NMR (CDCl3), δ: 199.0 (s, C(2)); 156.3 (d, C(4)); 136.6
(d, C(6)); 126.9 (d, C(3)); 125.9 (d, C(7)); 38.4 (s, C(5)); 28.3
(2 q, CMe2); 26.9 (q, C(1)); 14.3 (s, C(8)). MS, m/z (Irel (%)):
152 [M]+ (2), 138 (7), 137 (65), 123 (17), 110 (9), 109 (92),
107 (5), 95 (20), 94 (9), 93 (10), 91 (9), 82 (11), 81 (17), 79 (31),
77 (12), 69 (6), 67 (50), 65 (6), 55 (22), 53 (9), 43 (100), 41
(20), 39 (14).
transꢀpꢀMenthaꢀ2(3),8(9)ꢀdiene (19) was obtained by therꢀ
molysis of 2ꢀcarene for 3 h at 220 °C. The 1H NMR spectrum of
compound 19 coincides with published data.13 13C NMR
(CDCl3), δ: 149.4 (s, C(8)); 134.0 (d, C(3) or C(2)); 129.2 (d,
C(2) or C(3)); 109.6 (t, C(9)); 43.5 (d, C(4)); 31.0 (t, C(6));
30.3 (d, C(1)); 28.0 (t, C(5)); 21.7 (q, C(10)); 20.4 (q, C(7)).
MS, m/z (Irel (%)): 136 [M]+ (55), 122 (5), 121 (52), 108 (13),
107 (68), 105 (13), 95 (8), 94 (21), 93 (84), 92 (10), 91 (36), 81
(12), 80 (13), 79 (100), 78 (7), 77 (31), 68 (33), 67 (31), 65 (9),
55 (18), 53 (16), 51 (8), 43 (8), 41 (24), 39 (22).
1RꢀAcetylꢀ4Rꢀmethylꢀ2ꢀcyclohexene (20). Rf 0.61 (CH2Cl2).
1H NMR (CDCl3), δ: 0.96 (d, 3 H, C(9)H3, J9,4 = 7.1 Hz); 2.15
(s, 3 H, C(8)H3); 3.07 (m, 1 H, H(1)); 5.68 (m, 2 H, H(2),
H(3)). MS, m/z (Irel (%)): 138 [M]+ (30), 123 (12), 96 (8), 95
(100), 94 (15), 93 (14), 91 (6), 80 (9), 79 (19), 77 (11), 67 (41),
65 (5), 55 (18), 53 (7), 43 (61), 41 (9), 39 (8).
1SꢀAcetylꢀ4Rꢀmethylꢀ2ꢀcyclohexene (21). Rf 0.61 (CH2Cl2).
1H NMR (CDCl3), δ: 0.95 (d, 3 H, C(9)H3, J9,4 = 7.1 Hz); 2.16
(s, 3 H, C(8)H3); 3.01 (m, 1 H, H(1)); 5.73 (br.s, 2 H, H(2),
H(3)). MS, m/z (Irel (%)): 138 [M]+ (17), 123 (7), 96 (9), 95
(100), 94 (16), 93 (11), 91 (4), 80 (9), 79 (13), 77 (9), 67 (37),
65 (4), 55 (16), 53 (6), 43 (60), 41 (9), 39 (7).
NMR spectra were recorded on a Bruker DRXꢀ500 specꢀ
trometer (500.132 (1H) and 125.758 MHz (13C)) at room temꢀ
perature (+25 °C) for solutions in CDCl3 with a concentration
of 25—50 mg mL–1. The solvent signals δ 7.24 (CHCl3) and
H
δ
76.90 (CDCl3) were used as internal standards. IR spectra
C
were recorded on a Bruker Vectorꢀ22 instrument for 2% soluꢀ
tions in CHCl3. Highꢀresolution mass spectra were measured on
a Finnigan MAT 8200 spectrometer (50—100 °C, EI, 70 eV).
The optical rotation was determined on a Polamat A polarimꢀ
eter at λ = 578 nm.
Oxidation of olefins with nitrous oxide (general procedure).
The oxidation experiments were carried out in a 25ꢀcm3 stainꢀ
lessꢀsteel autoclave type reactor (Parr) equipped with a manomꢀ
eter and a magnetic stirrer. A solution of olefin (0.5 g) in benꢀ
zene (10 cm3) was placed into the reactor and the reactor was
tightly covered with a lid. Air was removed from the reactor by
vacuum pump for 30 s, the reactor was purged with nitrous
oxide, and then N2O was introduced to an equilibrium pressure
of 25 atm. After addition of the reactants, the reactor was heated
at a rate of 6 °C min–1 to 250 °C (during heating, the pressure in
the reaction system increased to 50—70 atm) and the system was
kept for 12 h at this temperature. After completion of the experiꢀ
ment, the reactor was cooled to room temperature, pressure was
slowly reduced, and the composition of the reaction mixture was
analyzed by GC/MS. The resulting benzene solution was conꢀ
centrated in vacuum of a waterꢀjet pump. The mixture compoꢀ
nents were separated using a combination of column chromaꢀ
tography (KSK silica gel with particle size of 0.140—0.315 mm
activated for 6 h at 130 °C; a hexane—ethyl acetate mixture
1R,4RꢀpꢀMenthꢀ2ꢀenꢀ9ꢀal (22) (1 : 1 diastereomer mixture).
(2)
Rf 0.55 (CH2Cl2). 1H NMR (CDCl3), δ: 0.95 (3 H, C(10)H3
,
J10,8 = 2.8 Hz); 0.97 (3 H, C(10)H3(1), J10,8 = 2.8 Hz); 1.03
(3 H, C(7)H3(1), J7,1 = 7.0 Hz); 1.04 (3 H, C(7)H3(2), J7,1
7.0 Hz); 5.44 (d, 2 H, H(2)(1) + H(2)(2), J2,3 = 10.0 Hz); 5.59 (d,
=
2 H, H(3)(1) + H(3)(2), J3,2 = 10.0 Hz); 9.67 (d, 1 H, H(9)(1)
J9,8 = 1.8 Hz); 9.69 (d, 1 H, H(9)(2), J9,8 = 1.5 Hz). MS,
m/z (Irel (%)): 152 [M]+ (7), 123 (14), 121 (7), 109 (9), 95 (56),
,

Nitrous oxide oxidation of monoterpenoids
Russ.Chem.Bull., Int.Ed., Vol. 56, No. 6, June, 2007
1243
94 (100), 93 (16), 91 (10), 81 (27), 79 (51), 77 (14), 68 (13),
67 (34), 55 (20), 53 (9), 43 (7), 41 (17), 39 (12).
2. T. Yamada, K. Hashimoto, Y. Kitaichi, K. Suzuki, and
T. Ikeno, Chem. Lett., 2001, 268; R. BenꢀDaniel, L. Weiner,
and R. Neumann, J. Am. Chem. Soc., 2002, 124, 8788;
T. Yamada, Bull. Chem. Soc. Jpn, 2004, 77, 1905.
3. B. Ohtani, S. Takamiya, Y. Hirai, M. Sudoh, S. Nishimoto,
and T. Kagiya, J. Chem. Soc., Perkin Trans., 1992, 175;
K. Hashimoto, Y. Kitaichi, H. Tanaka, T. Ikeno, and
T. Yamada, Chem. Lett., 2001, 922; R. BenꢀDaniel and
R. Neumann, Angew. Chem., 2003, 115, 96; T. L.
Stuchinskaya and I. V. Kozhevnikov, Catal. Commun., 2004,
609; T. L. Stuchinskaya, M. Musawir, E. F. Kozhevnikova,
and I. V. Kozhevnikov, J. Catal., 2005, 231, 41.
4. G. I. Panov, K. A. Dubkov, E. V. Starokon, and V. N.
Parmon, React. Kinet. Catal. Lett., 2002, 76, 401; G. I. Panov,
K. A. Dubkov, and E. V. Starokon, React. Kinet. Catal. Lett.,
2002, 77, 197; S. V. Semikolenov, K. A. Dubkov, E. V.
Starokon´, D. E. Babushkin, and G. I. Panov, Izv. Akad.
Nauk. Ser. Khim., 2005, 925 [Russ. Chem. Bull., Int. Ed.,
2005, 54, 948].
3ꢀIsopropenylꢀ1ꢀmethylꢀ2ꢀmethylidenecyclopentanol (23)
(a 7 : 3 diastereomer mixture) was obtained by thermolysis of
dehydrolinalool for 1 h at 240 °C. The diastereomers were sepaꢀ
rated by column chromatography on SiO2 (a hexane—AcOEt
mixture with AcOEt concentration gradient from 0 to 30% was
used as the eluent); Rf 0.56 and 0.49 (hexane—AcOEt, 1 : 1 v/v).
The NMR spectra of the isolated isomers were identical to
those described previously.14 MS for the major diastereomer,
m/z (Irel (%)): 152 [M]+ (1), 137 (50), 134 (16), 123 (11), 121
(20), 119 (43), 109 (47), 105 (11), 97 (14), 95 (85), 94 (89), 93
(27), 91 (32), 84 (14), 81 (35), 80 (10), 79 (100), 77 (26), 71
(12), 69 (22), 67 (41), 65 (10), 55 (18), 53 (16), 43 (88), 41
(25), 39 (22). MS for the minor diastereomer, m/z (Irel (%)):
152 [M]+ (1), 137 (100), 134 (71), 123 (13), 119 (48), 109 (58),
105 (10), 95 (23), 94 (13), 93 (23), 91 (32), 84 (22), 81 (31), 79
(78), 77 (25), 71 (12), 69 (26), 67 (40), 55 (18), 53 (15), 43 (85),
41 (26), 39 (23).
1ꢀAcetylꢀ3ꢀhydroxyꢀ2,3ꢀdimethylcyclopentꢀ1ꢀene (26).
Rf 0.27 (hexane—AcOEt, 1 : 1 v/v). H NMR (CDCl3), δ: 1.27
5. E. V. Starokon, K. A. Dubkov, D. E. Babushkin, V. N.
Parmon, and G. I. Panov, Adv. Synth. Catal., 2004, 346, 268.
6. S. V. Semikolenov, K. A. Dubkov, L. G. Echevskaya, M. A.
Mats´ko, E. B. Burgina, D. E. Babushkin, V. A. Zakharov,
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V. N. Parmon, and G. I. Panov, J. Polym. Sci., Part A:
Polym. Chem., 2006, 44, 2510.
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hedron Lett., 1969, 4651; J. P. Daub and J. A. Berson, Tetraꢀ
hedron Lett., 1984, 25, 4463; Y.ꢀL. Lin and E. Turos, J. Am.
Chem. Soc., 1999, 121, 856.
1
(s, 3 H, C(9)H3); 1.85 (ddd, 1 H, H(4), J4,4´ = 13.4 Hz, J4,5
7.2 Hz, J4,5´ = 9.2 Hz); 1.91 (br.s, OH); 1.99 (t, 3 H, C(8)H3,
8,5´ = 2.0 Hz); 2.01 (ddd, 1 H, H(4´), J4´,4 = 13.4 Hz, J4´,5
=
J
=
8.1 Hz, J4´,5´ = 2.0 Hz); 2.22 (s, 3 H, C(7)H3); 2.42 (ddd, 1 H,
H(5), J5,5´ = 15.8 Hz, J5,4´ = 8.1 Hz, J5,4 = 7.2 Hz); 2.60 (dddq,
1 H, H(5´), J5´,5 = 15.8 Hz, J5´,4 = 9.2 Hz, J5´,4´ = 2.0 Hz,
J5´,8 = 2.0 Hz). 13C NMR (CDCl3), δ: 199.2 (s, C(6)); 154.9
(s, C(2)); 135.3 (s, C(1)); 84.7 (s, C(3)); 38.8 (t, C(4)); 30.0
(q, C(7)); 29.7 (t, C(5)); 24.7 (q, C(9)); 11.5 (q, C(8)).
IR (CHCl3), ν/cm–1: 3598, 1678, 1653. MS, m/z (Irel (%)):
154.09916 (154.09937 for C9H14O2) [M]+ (5), 139 (29), 136
(15), 127 (6), 121 (7), 111 (13), 99 (5), 97 (8), 93 (5), 85 (10),
77 (5), 69 (6), 67 (6), 57 (5), 55 (8), 53 (5), 43 (100), 41 (9),
39 (8), 29 (5), 28 (10), 27 (6).
8. G. Ohloff, Tetrahedron Lett., 1965, 3795.
2ꢀHydroxyꢀ5ꢀisopropylideneꢀ2ꢀmethylcyclopentanone (27).
Rf 0.42 (hexane—AcOEt, 1 : 1 v/v). The H NMR spectrum of
compound 27 coincides with published data.15 13C NMR
(CDCl3), δ: 208.0, 151.7, 127.7, 78.1 (all s); 33.9, 24.2 (both t);
24.1, 23.8, 20.9 (all q).
9. M. B. Erman, G. V. Cherkaev, S. E. Gulyi, and V. B.
Mochalin, Zh. Org. Khim., 1991, 27, 655 [Russ. J. Org. Chem.,
1991, 27, 565 (Engl. Transl.)].
10. A. V. Tkachev, Biblioteka khromatoꢀmassꢀspektrometriꢀ
cheskikh dannykh letuchikh veshchestv rastitel´nogo
proiskhozhdeniya [Library of GC/MS Data for Volatile Comꢀ
pounds of Plant Origin], Novosibirskii Inst. Organ. Khimii
im. N. N. Vorozhtsova SO RAN, Novosibirsk, 2006 (in
Russian).
11. W. Engel, J. Agric. Food Chem., 2002, 50, 1686.
12. J.ꢀC. Limasset, P. Amice, and J.ꢀM. Conia, Bull. Soc.
Chim. Fr., 1969, 3981.
13. K. Gollnick and G. Schade, Tetrahedron, 1966, 22, 123; I. I.
Berdyshev, V. I. Lysenkov, D. A. Fesenko, and B. G. Udarov,
Zh. Organ. Khim., 1975, 11, 593 [J. Org. Chem. USSR, 1975,
11 (Engl. Transl.)].
1
2ꢀHydroxyꢀ3ꢀisopropylideneꢀ2ꢀmethylcyclopentanone (28).
1
Rf 0.42 (hexane—AcOEt, 1 : 1 v/v). H NMR (CDCl3), δ: 1.25
(s, 3 H); 1.79 (ddq, 3 H, J = 2.3 Hz, J = 1.5 Hz, J = 0.8 Hz);
1.91 (q, 3 H, J = 0.8 Hz). 13C NMR (CDCl3), δ: 202.1, 154.8,
127.8, 72.0 (all s); 35.0, 30.8 (both t); 24.3, 21.2, 11.2 (all q).
Retention indexes of the compounds: 1136 (7), 1182 (8),
1130 (9), 1215 and 1217 (10), 1197 (11´), 1205 (11″), 1332 (12),
1348 (13), 1194 (14´), 1187 (14″), 1142 (15), 1022 (17a), 1024
(17b), 970 (18), 973 (19), 1097 (20), 1087 (21), 1175 and 1176
(22), 1071 and 1092 (23), 1272 (26), 1209 (27), 1220 (28).
14. B. M. Trost, M. Lautens, C. Chan, D. J. Jebaratnam, and
T. Mueller, J. Am. Chem. Soc., 1991, 113, 636; S. Araki,
A. Imai, K. Shimizu, M. Yamada, A. Mori, and Y. Butsugan,
J. Org. Chem., 1995, 60, 1841.
15. C. Maignan and F. Rouessac, Bull. Soc. Chim. Fr.,
1973, 1454.
References
1. G. I. Panov, A. K. Uriarte, M. A. Rodkin, and V. I. Sobolev,
Catal. Today, 1998, 4, 365; A. V. Leont´ev, O. A. Fomicheva,
M. V. Proskurnina, and N. S. Zefirov, Usp. Khim., 2001, 70,
107 [Russ. Chem. Rev., 2001, 70 (Engl. Transl.)]; V. N.
Parmon, G. I. Panov, A. K. Uriarte, and A. S. Noskov,
Catal. Today, 2005, 100, 115.
Received April 3, 2007;
in revised form May 8, 2007