Reaction of 1-ethoxyisoindole with maleimide and its derivatives

Article abstract of DOI:10.3987/COM-12-12501

We have reported1 the possibility of conducting the Diels-Alder [4+2]-cycloaddition reaction with isoindoles that exist predominantly in the isoindoline form, due to the Curtin-Hammet principle. Pursuing our research, we used 1-ethoxyisoindole as the most evident analog of 1-aminoisoindole. This compound is a typical simple isoindole existing chiefly as the isoindoline tautomer. We have studied the reactions of 1-ethoxyisoindoles with maleimide and its derivatives as active dienophiles. In addition, this paper describes the synthesis of a novel compound - tri-(2-methoxycarbonyl)benzylamine.

Full text of DOI:10.3987/COM-12-12501

HETEROCYCLES, Vol. 85, No. 7, 2012
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HETEROCYCLES, Vol. 85, No. 7, 2012, pp. 1671 - 1681. © 2012 The Japan Institute of Heterocyclic Chemistry
Received, 2nd May, 2012, Accepted, 29th May, 2012, Published online, 5th June, 2012
DOI: 10.3987/COM-12-12501
REACTION OF 1-ETHOXYISOINDOLE WITH MALEIMIDE AND ITS
DERIVATIVES
Igor V. Levkov,a Stephanie Cassel,c Zoia V. Voitenko,a* Gennady V.
Palamarchuk,b Oleg V. Shishkin,b Svetlana V. Shishkina,b Armand Lattes,c
and Isabelle Rico-Lattesc
aKiev National Taras Shevchenko University, 64 Str Volodymyrs’ka, 01033 Kiev,
Ukraine
bSTC "Institute for Single Crystals" NASU, 60 Lenina ave, 61001 Kharkiv,
Ukraine
c Laboratory IMRCP, UMR CNRS 5623, University Paul Sabatier, 118 route de
Narbonne, 31066 Toulouse Cedex 4, France
*Zoia V. Voitenko. Tel.: +38-096-449-2900; fax: +38-044-235-1273; e-mail:
z_voitenko@mail.univ.kiev.ua
Abstract – We have reported1 the possibility of conducting the Diels-Alder
[4+2]-cycloaddition reaction with isoindoles that exist predominantly in the
isoindoline form, due to the Curtin-Hammet principle. Pursuing our research, we
used 1-ethoxyisoindole as the most evident analog of 1-aminoisoindole. This
compound is a typical simple isoindole existing chiefly as the isoindoline
tautomer. We have studied the reactions of 1-ethoxyisoindoles with maleimide
and its derivatives as active dienophiles. In addition, this paper describes the
synthesis of a novel compound – tri-(2-methoxycarbonyl)benzylamine.
INTRODUCTION
Isoindole derivatives have found use in versatile fields: they are employed as antihypertensive,2
antiinflamatory,2 anorectic3,4 agents. Some of these compounds have fungicidal properties.5 A family of
isoindole-based dyes with specific properties was created.6-8
Isoindole possesses interesting structural properties. The isoindole-isoindoline tautomerism is one of the
key aspects in the chemistry of isoindole.9-14 Notable is the Diels-Alder [4+2]-cycloaddition reaction,

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HETEROCYCLES, Vol. 85, No. 7, 2012
which can be used both for identification of unstable isoindoles, and to obtain unusual spatial structures,
unaccessible by other methods.15
The cycloaddition reactions have been carried out for those isoindoles that exist predominantlyin the diene
form. In earlier reports1 we have shown that though 1-aminoisoindole's most favorable tautomeic form is
the isoindoline one, it can undergo Diels-Alder cycloaddition due to the Curtin–Hammett principle.
In the current publication we describe our ongoing investigation of the isoindole-isoindoline tautomerism
and the possibility of reactions with dienophiles when the isoindoline form is prevalent. 2-Unsubstituted
1-ethoxyisoindole, which also exists chiefly in the isoindoline form, was chosen as a suitable analog of
1-aminoisoindole.16 This compound is of interest because it is able to undergo condensation reactions
with the formation of various fused isoindoles, and its derivatives are used to obtain anticholesterol
medications.17
RESULTS AND DISCUSSION
The reactivity of isoindoles in [4+2]-cycloaddition reactions is generally attributed to tautomerism. For
unsubstituted isoindole two tautomeric forms are relevant: the isoindoline 1а and the isoindole 1b. The
presence of the isoindole diene tautomer in the equilibium gives us the possibility of Diels-Alder
cycloaddition for isoindoles.
Scheme 1. Tautomerism of unsubstituted isoindole 1 and 1-ethoxyisoindole 2
1-Ethoxyisoindole, in the same way as 1-aminoisoindole, exists predominantly in the isoindoline form 2а.
In contrast to unsubstituted 1-ethoxyisoindole, the 2-substituted analogs smoothly undergo
cycloaddition,18,19 as the isoindole form is their only possible tautomer. We therefore sought to use the
Curtin–Hammett principle when conducting reactions of 1-ethoxyisoindoles with maleimide derivatives
as dienophiles.
1-Ethoxyisoindole was obtained via alkylation of phthalimidine 4 with triethyloxonium tetrafluoroborate.
Phthalimidine 4 was synthesized from the methyl ester of 2-bromomethylbenzoic acid20 3.

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When methyl 2-bromomethylbenzoate 3 was reacted with aqueous ammonia (25%),20 besides the
expected phthalimidine an earlier undescribed compound 5 was isolated. The reaction mixture was easily
separated due to the difference in solubilities of the products in methanol. The mixture was stirred with
methanol, product 5 was filtered off and the solution of phthalimidine 4 in methanol was evaporated
under reduced pressure. The formation of compound 5 is explained by synchronous triple alkylation of
ammonia with the 2-bromomethylbenzoic acid ester, which is not followed by a successive condensation
involving the methoxycarbonyl group. The structure of compound 5 is confirmed by spectral and X-ray
data.
Scheme 2. Synthesis of 1-ethoxyisoindolium tetrafluoroborate 6
According to X-ray diffraction data the nitrogen atom in amine 5 has pyramidal configuration (sum of
bond angles centered at the N(1) atom is 330.0º). Substituents adopt the propeller-like conformation. All
aromatic rings are almost co-planar to the corresponding C-N(1) bond (the N(1)-C(9)-C(8)-C(7) torsion
angles are -4.4(4)º for ring A, -10.4(4)º for B and -11.0(3)º for C). The benzene rings adopt antiperiplanar
conformation with
respect to
one N(1)-C(9) bond (the C(8A)-C(9A)-N(1)-C(9C),
C(8B)-C(9B)-N(1)-C(9A) and the C(8C)-C(9C)-N(1)-C(9B) torsion angles are 157.1(2)º, 161.0(2)º and
158.7(2)º, respectively) and they are almost orthogonal with respect to other N(1)-C(9) bond (the the
C(8A)-C(9A)-N(1)-C(9B), C(8B)-C(9B)-N(1)-C(9C) and the C(8C)-C(9C)-N(1)-C(9A) torsion angles
are -81.4(3)o, -78.3(3)o and -79.5(3)o, respectively). The orientation of the substituents at the nitrogen
atom differs from the orientation of ester groups. In the case of ring A methoxy group is oriented toward
the nitrogen atom (the C(8)-C(3)-C(2)-O(1) torsion angle is 14.4(4)º) while in rings B and C it has an
opposite orientation (the same torsion angle is -165.3(3)º for B and -161.3(2) for C).

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HETEROCYCLES, Vol. 85, No. 7, 2012
Figure 1. Structure of compound 5 according to X-ray diffraction data
1-Ethoxyisoindole tetrafluoroborate 6 obtained by a literature procedure21 was then reacted with
N-substituted maleimides 7а-d. The reaction was carried out in methanol at room temperature. The free
base 1-ethoxyisoindole was generated in situ by the addition of triethylamine. The reaction was
performed using the 1:1 and 1:2 ratio of reactants.
Ratio 1:1
Ratio 1:2
Maleimide
R
Yield of 8
Yield of 9
4%
Yield of 8
Yield of 9
9%
Ph
Me
48%
53%
7a
7b
7c
7d
-
49%
-
42%
-
-
51%
-
47%
-
H
p-C6H4-Me
44%
46%
Scheme 3. Interaction of 1-ethoxyisoindole with maleimides 7a–d in the ratio 1:1 and 1:2
Eminently, regardless of the ratio of reactants, each maleimide yielded the same products in both cases.
Slightly better yields of the adducts were observed for 1:2 ratio.

HETEROCYCLES, Vol. 85, No. 7, 2012
1675
It is notable that by varying substituents at the maleimide nitrogen atom we can selectively obtain either
mono- or bis-Michael adduct. Thus, in the case of methyl group, the final product is the bis-adduct. On
the contrary, using unsubstituted maleimide results in mono-adduct as the final product. The major
product at the reaction of 1-ethoxyisoindole with N-phenylmaleimide is the mono-adduct. If it is filtered
off and the reaction mixture allowed to stand for some more time, a small amount of the bis-Michael
adduct can be isolated. For tolyl group, the final product is the bis-adduct. The reason for the described
situation is the different solubilities of 8 and 9 with different substituents: if the mono-adduct is soluble, it
can react with the second molecule of maleimide, thus forming the bis-adduct which is less soluble and
precipitates out.
The structure of the obtained adducts was confirmed by spectral data. The structure of bis-adduct 9b was
in addition confirmed by X-ray diffraction study.
Figure 2. Structure of compound 9b according to X-ray diffraction data
Asymmetric part of unit cell of crystals 9b contains two molecules (A and B) differing in orientation of
ethoxy group (the C(8)-O(1)-C(9)-C(10) torsion angle is 81.2º for molecule A and -94.1o for molecule B).
Five-membered rings of succinimidyl fragments adopt an envelope conformation. The deviations of the
C(12) and C(19) atoms from the mean plane of the remaining atoms of the ring are 0.10(2) Å and -0.10(1)
Å in molecule A and 0.13(3) Å and 0.17(1) Å in B. Non-planarity of rings is promoted by steric repulsion
between succinimidyl and isoindole fragments (shortened intramolecular contacts H(12A)…C(2A) 2.61
Å in molecule A, H(12D)…C(2B) 2.59 Å in molecule B (van der Waals radii sum22 is 2.87 Å),
H(12A)…C(7) 2.76 Å A and B, H(12A)…C(8) 2.74 Å A, 2.78 Å B, H(19A)…C(2) 2.77 Å A and B,
H(19A)…C(8) 2.70 Å A and B, H(16A)…C(14) 2.70 Å A and B H(16A)…O(3) 2.41 Å A, 2.40 Å B (van
der Waals radii sum is 2.46 Å), H(19A)…N(1) 2.58 Å A and B (van der Waals radii sum is 2.66 Å).
These substituents have similar orientation with respect to the isoindole fragment (the
N(1)-C(1)-C(11)-C(12) and N(1)-C(1)-C(16)-C(19) torsion angles are 57.0(6)° and -54.2(6)° in molecule

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HETEROCYCLES, Vol. 85, No. 7, 2012
A, 57.3(6)° and -59.5(6)° in molecule B, respectively).
We successfully obtained phthalimidine derivatives of mono-Michael adducts with high yields. The
reactions were performed in 0.01 M aqueous HCl at room temperature for 24 h, the products were
collected by filtration.
Scheme 4. Hydrolysis of compound 8a,c with the formation of phtalimidine derivatives 10a,c
In the case of bis-Michael adducts no corresponding products were formed. Increasing the concentration
of HCl and using elevated temperatures resulted in the degradation of the substrates due to amide bonds
hydrolysis in the maleimide and phthalimidine fragments.
CONCLUSIONS
Our work presents the reaction of 1-ethoxyisoindole with maleimides. We have shown that the reactions
afforded 1:1 or 1:2 adducts, depending on the substituents at the nitrogen atom in maleimide. In addition,
we
have
proposed
a
procedure
for
the
synthesis
of
the
novel
compound
tri-(2-methoxycarbonyl)benzylamine. The structure of the obtained products is confirmed by spectral data
and X-ray diffraction data.
EXPERIMENTAL
The NMR spectra (400.396 MHz) were recorded with a Varian Mercury 400 with TMS as internal
standard. The IR-spectra were recorded on Specord M82. The chromatomass-spectra were recorded on
Agilent 1100 Series with selective detector Agilent LC/MSD SL. Elemental analysis was realised with a
Carlo Erba Strumenization analyser.
Procedure of the reaction of methyl ester of 2-bromomethylbenzoic acid20 3 with ammonia
Methyl ester of 2-bromomethylbenzoic acid20 3 (4.0 g, 0.017 mol) was added dropwise to the cooled

HETEROCYCLES, Vol. 85, No. 7, 2012
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aqueous ammonia solution (25%) at 5 °C with intensive stirring. The solution was kept at room
temperature for 12 h. The solvent was evaporated under reduced pressure. The residue was dissolved in
water und heated to 90 °C. The oil phase was removed and charcoal was added. The mixture was heated
for 1 h and the charcoal was filtered off from the hot solution. After cooling the formed precipitate was
filtered. The mixture was dissolved in hot methanol and unsoluble product 5 was filtered and washed with
MeOH. The filtrate was evaporated under reduced pressure with the formation of phthalimidine 4 with
78% yield (1.77 g). Spectral data for phthalimidine 4 was fully identical to the previously described in the
literature.23
(5). 0.94 g, 12%, white solid, mp 135 °C; Anal. Calcd for C27H27NO6: C, 70.27; H, 5.90; N, 3.03. Found:
C, 70.39; H, 5.85; N, 2.78; νmax (KBr) 3408, 3132, 3016, 2964, 2852, 1712, 1600, 1580, 1444, 1304, 1280,
1096, 1084, 1028, 768 cm-1 ; δH (400 MHz, DMSOd6) 3.78 (s, 9H), 3.89 (s, 6H), 7.29 (t, 3H), 7.49 (t, 3H),
7.71 (d, 3H); 7.73 (d, 3H); δC (100 MHz, DMSOd6) 52.4, 55.9, 127.3, 129.8, 130.1, 130.8, 132.2, 140.0,
168.0; MS (EI): M+, found 461. C27H27NO6 required 461.
Common procedure for the reaction of 1-ethoxyisoindolium tetrafluoroborate21 6 with maleimides
7a–d
To a solution of 1-ethoxyisoindolium tetrafluoroborate 6 (0.7 g, 2.0 mmol) in MeOH (5 mL) was added the
relevant maleimide 7a–d (4.0 mmol). Triethylamine (1 mL, 7.2 mmol) was then added and the flask was
sealed tightly with a stopper. After 24 h the mixture produced white plate-formed crystals. The residue was
filtered and washed with MeOH. In the case of N-phenylmaleimide 7a the filtrate was left for 24 h more to
give compound 9a as a precipitate.
(8a). 0.35 g, 53%, white solid, mp 177 °C; Anal. Calcd for C20H18N2O3: C, 71.84; H, 5.43; N, 8.38.
Found: C, 70.86; H, 5.32; N, 8.46; νmax (KBr) 3468, 3064, 2976, 2944, 1712, 1620, 1596, 1572, 1500,
1408, 1388, 1344, 1192, 1028, 712 cm-1; δH (400 MHz, DMSOd6) 1.25 (dd, J = 4.0, 17.6 Hz, 1H), 1.39 (t,
3H), 2.43 (dd, J = 9.2, 17.6 Hz, 1H), 3.84 (ddd, J = 3.6, 4.0, 9.2 Hz, 1H), 4.43 (q, 2H), 5.19 (d, J = 3.6 Hz,
1H), 7.25 (d, 2H), 7.42-7.57 (m, 6H), 7.73 (d, 1H); δC (100 MHz, DMSOd6) 14.7, 28.9, 42.3, 64.4, 68.0,
120.8, 123.3, 127.5, 128.8, 129.5, 130.4, 133.1, 133.5, 151.5, 170.3, 176.0, 178.2; MS (EI): M+, found
334. C20H18N2O3 required 334.
(8c). 0.26 g, 51%, white solid, mp 234 °C; Anal. Calcd for C14H14N2O3: C, 65.11; H, 5.46; N, 10.85.
Found: C, 64.92; H, 5.34; N, 10.74; νmax (KBr) 3462, 3132, 2974, 2746, 1712, 1604, 1584, 1552, 1404,

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1372, 1336, 1186, 1176, 1024, 798, 752 cm-1; δH (400 MHz, DMSOd6) 1.16 (dd, J = 4.0, 17.6 Hz, 1H),
1.40 (t, 3H), 2.13 (dd, J = 9.2, 17.6 Hz, 1H), 3.62 (ddd, J = 3.6, 4.0, 9.2 Hz, 1H), 4.40 (q, 2H), 5.09 (d, J
= 3.6 Hz, 1H), 7.43-7.53 (m, 3H), 7.65 (d, 1H), 11.12 (s, NH); δC (100 MHz, DMSOd6) 14.7, 29.6, 43.3,
64.4, 67.3, 120.7, 123.1, 128.6, 130.3, 133.3, 151.9, 170.1, 178.2, 180.3; MS (EI): M+, found 258.
C14H14N2O3 required 258.
(9a). 0.09 g, 9%, white solid, mp 256 °C; Anal. Calcd for C30H25N3O5: C, 70.99; H, 4.96; N, 8.28. Found:
C, 70.8.3; H, 4.83; N, 8.57; νmax (KBr) 3432, 3064, 2972, 2912, 2844, 1692, 1560, 1488, 1376, 1180, 700
cm-1; δH (400 MHz, DMSOd6) 1.13 (dd, J = 3.2, 18.0 Hz, 1H), 1.33 (dd, J = 4.8, 18.0 Hz, 1H), 1.41 (t,
3H), 2.57 (dd, J = 8.8, 18.0 Hz, 1H), 2.70 (dd, J = 9.6, 18.0 Hz, 1H), 4.46 (q, 2H), 4.67 (dd, J = 3.2, 8.8
Hz, 1H), 4.81 (dd, J = 4.8, 9.6 Hz, 1H), 7.17 (d, 2H), 7.22 (d, 2H), 7.42-7.66 (m, 10H); δC (100 MHz,
DMSOd6) 14.7, 31.1, 31.4, 42.4, 42.5, 65.0, 76.2, 121.7, 122.8, 127.5, 128.9, 129.0, 129.5, 129.6, 130.2,
131.6, 132.6, 133.0, 134.7, 150.1, 170.6, 175.2, 175.5, 177.1, 177.4; MS (EI): M+, found 507.
C30H25N3O5 required 507.
(9b). 0.36 g, 47%, white solid, mp 227 °C; Anal. Calcd for C20H21N3O5: C, 62.65; H, 5.52; N, 10.96.
Found: C, 62.78; H, 5.37; N, 10.74; νmax (KBr) 3396, 3056, 3000, 2940, 2864, 2820, 1700, 1588, 1420,
1280, 1252, 1180, 1120, 1064, 748 cm-1; δH (400 MHz, DMSOd6) 0.93 (dd, J = 3.2, 18.0 Hz, 1H), 1.07
(dd, J = 4.8, 18.0 Hz, 1H), 1.36 (t, 3H), 2.26 (dd, J = 8.8, 18.0 Hz, 1H), 2.47 (dd, J = 9.6, 18.0 Hz, 1H),
2.85 (s, 3H), 2.88 (s, 3H), 4.35 (q, 2H), 4.54 (dd, J = 3.2, 8.8 Hz, 1H), 4.69 (dd, J = 4.8, 9.6 Hz, 1H), 7.20
(d, 1H), 7.51 (m, 2H), 7.57 (d, 1H); δC (100 MHz, DMSOd6) 14.4, 24.7, 30.7, 30.9, 42.1, 42.2, 64.9, 75.7,
121.4, 122.4, 129.9, 131.4, 134.5, 150.1, 170.3, 176.0, 176.3, 178.0, 178.4; MS (EI): M+, found 383.
C20H21N3O5 required 383.
(9d). 0.49 g, 46%, white solid, mp 258 °C; Anal. Calcd for C32H29N3O5: C, 71.76; H, 5.46; N, 7.85.
Found: C, 71.63; H, 5.37; N, 7.71; νmax (KBr) 3460, 3036, 2984, 2920, 2864, 1704, 1620, 1572, 1516,
1388, 1348, 1192, 804, 776, 712 cm-1; δH (400 MHz, DMSOd6) 1.11 (dd, J = 3.2, 18.0 Hz, 1H), 1.31 (dd,
J = 4.8, 18.0 Hz, 1H), 1.42 (t, 3H), 2.42 (s, 6H), 2.57 (dd, J = 8.8, 18.0 Hz, 1H), 2.68 (dd, J = 9.6, 18.0 Hz,
1H), 4.47 (q, 2H), 4.67 (dd, J = 3.2, 8.8 Hz, 1H), 4.82 (dd, J = 4.8, 9.6 Hz, 1H), 7.05 (d, 2H), 7.11 (d, 2H),
7.29 (d, 4H), 7.41 (d, 1H), 7.60 (m, 2H), 7.65 (d, 1H); δC (100 MHz, DMSOd6) 14.7, 21.2, 31.0, 31.4,
42.4, 65.0, 76.2, 121.6, 122.8, 127.3, 129.9, 130.0, 130.2, 130.4, 131.5, 134.7, 138.4, 138.6, 150.1, 170.5,
175.3, 175.5, 177.2, 177.4; MS (EI): M+, found 535. C32H29N3O5 required 535.
Common procedure for the synthesis of phtalimidine 10a,c

HETEROCYCLES, Vol. 85, No. 7, 2012
1679
Compound 8a,c (1.0 mmol) was dispersed in 10 mL of an aqueous solution of hydrogen chloride (0.01M)
and kept at room temperature with vigorous stirring for 24 h. The residue was filtered and washed with
water and i-PrOH.
(10a). 0.29 g, 96%, white solid, mp 285 °C; Anal. Calcd for C18H14N2O3: C, 70.58; H, 4.61; N, 9.15.
Found: C, 70.67; H, 4.49; N, 8.98; νmax (KBr) 3404, 3160, 3060, 2916, 2856, 1708, 1488, 1376, 1176, 756,
700 cm-1; δH (400 MHz, DMSOd6) 1.68 (dd, J = 4.8, 18.0 Hz, 1H), 2.23 (dd, J = 9.2, 18.0 Hz, 1H), 3.61
(dd, J = 4.8, 9.2 Hz, 1H), 5.00 (s, 1H), 7.15-7.30 (m, 6H), 7.40 (t, 1H), 7.48 (t, 2H), 8.74 (s, NH); δC (100
MHz, DMSOd6) 28.6, 43.4, 55.4, 123.4, 123.7, 127.7, 128.8, 129.2, 132.6, 132.9, 133.1, 145.6, 170.7,
175.6, 176.9; MS (EI): M+, found 306. C18H14N2O3 requires 306.
(10c). 0.22 g, 94%, white solid, mp 268 °C; Anal. Calcd for C12H10N2O3: C, 62.60; H, 4.38; N, 12.17.
Found: C, 62.31; H, 4.27; N, 12.03; νmax (KBr) 3458, 3222, 3076, 2986, 2768, 1704, 1658, 1454, 1404,
1344, 1272, 1196, 1174, 874, 856, 774, 704 cm-1; δH (400 MHz, DMSOd6) 1.66 (dd, J = 4.8, 18.0 Hz,
1H), 2.22 (dd, J = 9.2, 18.0 Hz, 1H), 3.61 (dd, J = 4.8, 9.2 Hz, 1H), 5.07 (s, 1H), 7.47 (t, 1H), 7.58 (t, 1H),
7.65 (m, 2H), 8.80 (s, NH), 11.25 (s, 1H); δC (100 MHz, DMSOd6) 29.4, 44.5, 55.1, 123.3, 123.6, 129.0,
132.5, 133.1, 145.8, 170.6, 177.9, 179.2; MS (EI): M+, found 230. C12H10N2O3 required 230.
X-Ray diffraction study of compounds 5 and 9b
Crystallographic data and parameters of data collection and structure solution and refinement are listed in
Table 1. Intensities of reflections were measured on an automatic «Xcalibur 3» diffractometer (graphite
monochromated MoKα radiation, CCD-detector, ω scanning). Both structures were solved by direct
method using SHELX97 package.24 Positions of the hydrogen atoms were located from electron density
difference maps and refined using riding model with Uiso=nUeq of carrier non-hydrogen atom (n=1.5 for
methyl groups and 1.2 for other H atoms). Full-matrix least-squares refinement against F2 within
anisotropic approximation for non-hydrogen atom was performed. Final atomic coordinates, geometrical
parameters and crystallographic data have been deposited at the Cambridge Crystallographic Data Centre,
12 Union Road, Cambridge, CB2 1EZ, UK (fax: +44 1223 336033; e-mail: deposit@ccdc.cam.ac.uk).
CCDC dep. numbers of compounds 5 and 9b are 793684 and 793785, respectively.

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HETEROCYCLES, Vol. 85, No. 7, 2012
Table 1. Crystal data and structure refinement for 5 and 9b
Structure
5
C27H27NO6
461.50
a= 7.851(7),
b= 0.011(7),
c= 13.128(4),
β= 96.58(3)
293
9b
C20H21N3O5
383.40
a= 19.366(3),
b= 10.103(1),
c= 21.639(4),
β= 114.34(2),
293
Formula
M, (g/mmol)
Unit cell
dimensions, (Å, deg.)
Temperature, (K)
V, (Å3)
4659(3)
monoclinic
C2/c
3857.4(10)
monoclinic
P 21/c
Syngony
Space group
Z
8
8
F, (000)
1952
1616
Dcalc, (g/sm3)
μ(MoKα), (mm-1)
2θmax, (deg.)
Measured refl.
Independent refl.
Rint
1.316
1.320
0.093
0.096
60
50
27086
8881
6785
7919
0.170
0.128
Refl. With F>4σ(F)
Number of parameters
wR2
2018
3934
310
506
0.097
0.143
R1(F>4σ(F))
S
0.066
0.079
0.84
0.97
CCDC dep. Number
793684
793685
ACKNOWLEDGEMENTS
Researches were carried out in the context of IRG "Franco-Ukrainian Collaboration in Molecular
Chemistry". This work is supported by CNRS (16 avenue Edouard Belin, 31055 Toulouse Cedex 4,
France).
REFERENCES
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HETEROCYCLES, Vol. 85, No. 7, 2012
1681
66, 508.
2. D. Guy Dominic, Patent DE 2140099, 1972.
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