The synthesis of unsubstituted cyclic imides using hydroxylamine under microwave irradiation

Article abstract of DOI:10.3390/molecules13010157

Unsubstituted cyclic imides were synthesized from a series of cyclic anhydrides, hydroxylamine hydrochloride (NH₂OH·HCl), and 4-N,N-dimethylamino-pyridine (DMAP, base catalyst) under microwave irradiation in monomode and multimode microwaves. This novel microwave synthesis produced high yields of the unsubstituted cyclic imides for both the monomode (61-81%) and multimode (84-97%) microwaves.

Full text of DOI:10.3390/molecules13010157

Molecules 2008, 13, 157-169
molecules
ISSN 1420-3049
© 2008 by MDPI
www.mdpi.org/molecules
Full Paper
The Synthesis of Unsubstituted Cyclic Imides Using
Hydroxylamine under Microwave Irradiation†
Ellis Benjamin 1,* and Yousef Hijji 2
1
Department of Chemistry and Physics, Arkansas State University, State University, AR 72467, USA
E-mail: ellisbenjamin@astate.edu
2 Department of Chemistry, Morgan State University, Baltimore, MD 21251, USA
E-mail: yhijji@morgan.edu
† Initial data presented at the 11th International Electronic Conference on Synthetic Organic Chemistry,
ECSOC-11, http://www.usc.es/congresos/ecsoc/11/ECSOC11.htm, 1-30 November 2007, paper e007
* Author to whom correspondence should be addressed. ellisbenjamin@astate.edu
Received: 26 December 2007; in revised form: 21 January 2008 / Accepted: 22 January 2008 /
Published: 25 January 2008
Abstract: Unsubstituted cyclic imides were synthesized from a series of cyclic anhydrides,
hydroxylamine hydrochloride (NH2OH·HCl), and 4-N,N-dimethylamino-pyridine (DMAP,
base catalyst) under microwave irradiation in monomode and multimode microwaves. This
novel microwave synthesis produced high yields of the unsubstituted cyclic imides for
both the monomode (61 - 81%) and multimode (84 - 97%) microwaves.
Keywords: Hydroxylamine·HCl; unsubstituted cyclic imides; DMAP; microwaves.
Introduction
The unsubstituted cyclic imide is an important functionality which has been found to maintain
significant biological activity [1-3]. The synthesis of unsubstituted cyclic imides either by
conventional methods or microwave irradiation is often carried out under harsh conditions thereby
increasing byproduct formation [4]. Currently, there are several conventional and microwave
techniques to produce unsubstituted cyclic imides. Many conventional syntheses of unsubstituted

Molecules 2008, 13
158
cyclic imides use the reaction of cyclic anhydrides with reactants including ammonia, urea,
formamide, and lithium nitride [5-7]. Other conventional reactions catalyze the cyclization of acid-
amide functionalities forming unsubstituted cyclic imides.
These catalysts include
carbonyldiimidazole (CDI), DMAP, and AlCl3 [8, 9]. Additional microwave syntheses use the reaction
of cyclic anhydrides with urea or thiourea, formamide, benzonitrile, cyanate, thiocyanate,
DMAP/ammonium chloride, and ammonium acetate [10-15].
The application of microwave technology in many conventional syntheses offers many advantages
including increased product yields and decreased reaction times [16-19]. We wish to report the
synthesis of a series of unsubstituted cyclic imides using cyclic anhydrides, NH2OH·HCl, and DMAP
via a novel microwave technique. This novel microwave synthesis produced unsubstituted cyclic
imides in good yields within minutes.
Results and Discussion
Microwave Synthesis
The novel syntheses were conducted under microwave irradiation using hydroxylamine
hydrochloride, DMAP, and an array of cyclic anhydrides yielding the corresponding unsubstituted
cyclic imide. (Scheme 1) [20]. Although modifications of several experimental parameters gave
moderate yields of the N-hydroxy cyclic imides (~30 percent), repeated studies found that the
unsubstituted cyclic imides were the major products. Increased N-hydroxy cyclic imides yields were
identified at lower temperatures and shorter reaction times. These results contradict Sugamoto et al.,
whoreported that N-hydroxy cyclic imides were synthesized in high yield under similar conditions
[20]. The current data supports research done by Consonni et al., which found that cyclic N-
hydroxyimides are converted to unsubstituted cyclic imides under basic conditions [21]. Application of
this novel microwave technique can be used to synthesize many biologically important molecules
including that of streptimidone, a glutarimide antibiotic [22].
Scheme 1. The Synthesis of Unsubstituted Cyclic Imides
O
O
O
DMAP
NH
+
N OH
NH2OH·HCl
O
+
O
O
O
Major Product Minor Product
Whereas this novel microwave synthesis produced high yields of the unsubstituted cyclic imides,
no definite mechanism has been identified. One possible mechanism for unsubstituted cyclic imide
formation is the breakdown of hydroxylamine·HCl into ammonia and water (Scheme 2). Ammonia
production then promotes unsubstituted cyclic imide formation. A second possibility is the conversion
of cyclic N-hydroximide to the unsubstituted cyclic imide. Unsubstituted cyclic imides formation
appears to be enhanced by the addition of a base catalyst and additional heating.

Molecules 2008, 13
Scheme 2. Possible Mechanisms for the Hydroxylamine and Cyclic Anhydride Synthesis
159
O
O
O
NH3
Fast
+
DMAP
+
O
NH2OH(HCl)
NH
H2O
O
Major Product
O
O
O
O
O
Slow
NH
N OH
+
NH2OH(HCl) DMAP
O
O
Major Product
Minor Product
Monomode Microwave Synthesis
The monomode microwave synthesis furnished unsubstituted cyclic imides using hydroxylamine as
a source for nitrogen, DMAP, and cyclic anhydrides for the cyclic carbon backbone. The microwave
synthesis was done at 150 °C over 5 minutes with a maximum energy output of 300W, producing
between 61 and 81 isolated percent yields.
Table 1. Monomode Synthesis of Unsubstituted Cyclic Imides using NH2OH(HCl)/ DMAP.
NH2OH(HCl)/ DMAP (CEM Discover)
Entry
Imides
Time (min)
Temp (oC)
Yield (%)
O
1
5
150
70
NH
O
H
N
O
O
2
3
5
5
150
150
71
61
O
NH
O
O
4
5
150
61
NH
O
O
5
6
5
5
150
150
61
81
NH
O
O
NH
O

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160
Multimode Microwave Synthesis
A series of multimode microwave reactions were used to identify a cost effective alternative to the
more expensive monomode synthesis. This technique used similar reaction conditions and anhydrides
to that of the monomode microwave syntheses. The reaction times ranged from 1 to 3 minutes at full
power until the material melted and started to vigorously bubble. Isolated percent yields were between
84 and 97 percent.
Table 2. Multimode Synthesis of Unsubstituted Imides Using NH2OH and DMAP.
NH2OH and DMAP (Multimode)
Entry
1
Imides
Time (min)
Yield (%)
97
O
NH
2.68
O
H
N
O
O
2
3
1.82
1.20
96
96
O
NH
O
O
NH
4
1.57
84
O
Unsubstituted cyclic imides were produced in good yields in both the multimode and monomode
microwaves. Slightly higher isolated yields were found in the multimode reactions compared to the
monomode result. This variation may stem from energy output differences for the multimode (1100
W) and the monomode (300 W) microwaves.
Crystals isolated from this and previous unsubstituted cyclic imide syntheses were analyzed by
single crystal X-ray diffraction generating good structural data for the desired cyclic imide products
[23]. Specifically, the unsubstituted cyclic imide 3a,4,5,6,7,7a-hexahydro-1H-isoindole-1,3(2H)-dione
(4, Figure 1) was characterized by X-ray diffraction studies [24]. The crystal structure of this
compound has previously been reported by Wang and co-workers [25]. Our unpublished crystal data
found an unsubstituted cyclic imide bound in the cis position of a well defined cyclohexane ring (R
factor = 0.0393).

Molecules 2008, 13
161
Figure 1. Molecular Diagram of 3a,4,5,6,7,7a-Hexahydro-1H-isoindole-1,3(2H)-dione (4) [24].
Experimental
General
The monomode microwave reactions were carried out in a CEM Discover Microwave. Multimode
microwave reactions were done in a Kennmore Microwave Oven (Household) Output: 1100 Watts
(Frequency: 2450 MHz). All Gas Chromatograph Mass Spectrometry (GC-MS) was performed using a
Shimadzu GC-17A and GCMS-QP5050A Labsolutions system. All reagents were purchased from
Aldrich Chemical Company and were used without further purification. Since two different methods
are described in this article Method 1 will refer to synthesis carried out under monomode conditions,
while, Method 2 will refer to synthesis under multimode conditions. Only the GCMS data is given,
however unsubstituted cyclic imides data matched that reported earlier [15].
Phthalimide (1): Method 1. Phthalic anhydride (0.20 g, 1.35 mmol), NH2OH·HCl (0.09 g, 1.30 mmol),
and DMAP (0.04 g, 0.33 mmol) were thoroughly mixed in a CEM vial with a stirrer. This was capped
and heated in a CEM Discover microwave for 5 minutes at 150 oC. This was rapidly cooled to room
temperature yielding a dark brown solid. The reaction mixture was dissolved in AcOEt (4 mL) and
was washed with distilled water (2 x 2 mL). The organic layer was concentrated to obtain a white
solid (0.14 g, 70%); MS m/z 147 (M+) 104, 76, 50.
Phthalimide (1): Method 2. Phthalic anhydride (1.0 g, 6.75 mmol), NH2OH·HCl (0.54 g, 7.7 mmol),
and DMAP (0.08 g, 0.65 mmol) were mixed in an 8 mL Teflon capped vial. The mixture was allowed
to heat for 4 minutes and 11 seconds at 30 percent power in the multimode microwave and then cooled
to room temperature. The sample was dissolved in acetone and flash chromatographed using silica
(~30 g) with pure acetone as the mobile phase to obtain a yellow solid. Yield: 0.96 g (97%); MS m/z
147 (M+) 104, 76, 50.
Succinimide (2): Method 1. Succinic anhydride (0.20 g, 2.00 mmol), NH2OH·HCl (0.14 g, 2.0 mmol),
and DMAP (0.04 g, 0.33 mmol) were thoroughly mixed in a CEM vial with a stirrer. This was capped

Molecules 2008, 13
162
and heated in a CEM Discover microwave for 5 minutes at 150 °C. This was rapidly cooled to room
temperature yielding a dark brown solid. The reaction mixture was dissolved in AcOEt (4 mL) and
was washed with distilled water (2 x 2 mL). The organic layer was concentrated to obtain a white
solid (0.14 g, 71%); MS m/z 99 (M+) 56.
Succinimide (2): Method 2. Succinic anhydride (1.0 g, 10 mmol), NH2OH·HCl (0.80 g, 11 mmol), and
DMAP (0.12 g, 0.98 mmol) were mixed in an 8 mL Teflon capped vial. The mixture was allowed to
heat for 1 minute 49 seconds at full power in the multimode microwave and then cooled to room
temperature. The sample was dissolved in acetone and flash chromatographed using silica (~30 g)
with pure acetone as the mobile phase to obtain a yellow solid (0.95 g, 96%); MS m/z 99 (M+) 56.
cis-1,2-Cyclobutanedicarboximide (3): Method 1. cis-1,2-Cyclobutanedicarboxylic acid anhydride
(0.20 g, 1.59 mmol), NH2OH·HCl) (0.11 g, 1.58 mmol), and DMAP (0.04 g, 0.33 mmol) were
thoroughly mixed in a CEM vial with a stirrer. This was capped and heated in a CEM Discover
microwave for 5 minutes at 150 °C. This was rapidly cooled to room temperature yielding a white
solid. The reaction mixture was dissolved in AcOEt (4 mL) and was washed with distilled water (2 x 2
mL). The organic layer was concentrated to obtain a white solid (0.12 g, 61%); MS m/z 125 (M+) 82,
54.
cis-1,2-Cyclobutanedicarboximide (3): Method 2. cis-1,2-Cyclobutanedicarboxylic acid anhydride
(1.0 g, 7.9 mmol), NH2OH·HCl (0.63 g, 9.1 mmol), and DMAP (0.10 g, 0.82 mmol) were mixed in an
8 mL Teflon capped vial. The mixture was allowed to heat for 1 minute 12 seconds at full power in the
multimode microwave and then cooled to room temperature. The sample was dissolved in acetone and
flash chromatographed using silica (~30 g) with pure acetone as the mobile phase to obtain a light
brown solid, (0.95 g, 96%); MS m/z 125 (M+) 82, 54.
3a,4,5,6,7,7a-Hexahydro-1H-isoindole-1,3(2H)-dione (4): Method 1. cis-1,2-Cyclohexanedicarbo-
xylic acid anhydride (0.20 g, 1.30 mmol), NH2OH·HCl (0.09 g, 1.29 mmol), and DMAP (0.04 g, 0.33
mmol) were thoroughly mixed in a CEM vial with a stirrer. This was capped and heated in a CEM
Discover microwave for 5 minutes at 150 °C. This was rapidly cooled to room temperature yielding a
white solid. The reaction mixture was dissolved in AcOEt (4 mL) and was washed with distilled water
(2 x 2 mL). The organic layer was concentrated to obtain a white solid (0.12 g, 61%); MS m/z 153
(M+) 125, 99, 82, 67, 54, 41.
3a,4,5,6,7,7a-Hexahydro-1H-isoindole-1,3(2H)-dione (4): Method 2. cis-1,2-Cyclohexanedicarboxylic
acid anhydride (1.0 g, 6.5 mmol), NH2OH·HCl (0.51 g, 7.3 mmol), and DMAP (0.08 g, 0.65 mmol)
were mixed in an 8 mL Teflon capped vial. The mixture was allowed to heat for 1 minute 49 seconds
at full power in the multimode microwave and then cooled to room temperature. The sample was
dissolved in acetone and flash chromatographed using silica (~30 g) with pure acetone as the mobile
phase to obtain a white solid (0.83 g, 84%); MS m/z 153 (M+) 125, 99, 82, 67, 54, 41.

Molecules 2008, 13
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Glutarimide (5): Method 1. Glutaric anhydride (0.20 g, 1.75 mmol), NH2OH·HCl (0.12 g, 1.73 mmol),
and DMAP (0.04 g, 0.33 mmol) were thoroughly mixed in a CEM vial with a stirrer. This was capped
and heated in a CEM Discover microwave for 5 minutes at 150 °C. This was rapidly cooled to room
temperature yielding a dark brown solid. The reaction mixture was dissolved in AcOEt (4 mL) and
was washed with distilled water (2 x 2 mL). The organic layer was concentrated to obtain a light
brown solid (0.12 g, 61%); MS m/z 113 (M+) 70, 42.
3a,4,7,7a-Tetrahydro-4,7-ethano-1H-isoindole-1,3(2H)-dione (6): Method 1. cis-Bicyclo[2.2.2]oct-5-
ene-2,3-dicarboxylic acid anhydride (0.10 g, 0.56 mmol), NH2OH·HCl (0.05 g, 0.72 mmol) and
DMAP (0.02 g, 0.16 mmol) were mixed thoroughly in a CEM-sealed vial with a magnetic stirrer. The
mixture was heated for 5 min at 150 °C in a CEM Discover microwave powered at 150 W. The sample
was then cooled rapidly to 40 °C. The reaction mixture was dissolved in AcOEt (4 mL) and was
washed with distilled water (2 x 2 mL). The organic layer was concentrated to obtain a light brown
solid (0.08 g, 81 %); MS m/z 177 (M+) 149, 99, 78, 51.
Acknowledgements
The author would like to thank Earl Benjamin for his editorial work.
References and Notes
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crystalline dimers. Tetrahedron Lett. 2006, 47, 8993-8997.
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Sample Availability: Samples of the compounds are commerically available.
© 2008 by MDPI (http://www.mdpi.org). Reproduction is permitted for noncommercial purposes.

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Supporting Data
Table 1. Crystal Data for 3a,4,5,6,7,7a-Hexahydro-1H-isoindole-1,3(2H)-dione.
Identification code
Empirical formula
Formula weight
Temperature
3a,4,5,6,7,7a-Hexahydro-1H-isoindole-1,3(2H)-dione
C8H11NO2
153.18
203(2) K
0.71073 Å
Orthorhombic
P21 21 21
Wavelength
Crystal system
Space group
Unit cell dimensions
a = 6.7185(4) Å
b = 7.8339(4) Å
c = 14.2861(10) Å
751.91(8) Å3
α= 90°
β= 90°
γ = 90°
Volume
Z
4
Density (calculated)
Absorption coefficient
F(000)
1.353 Mg/m3
0.098 mm-1
328
Crystal size
0.65 x 0.55 x 0.35 mm3
4.91 to 32.46°.
Theta range for data collection
Index ranges
-4<=h<=9, -9<=k<=11, -20<=l<=18
5210
Reflections collected
Independent reflections
Completeness to theta = 25.00°
Absorption correction
Max. and min. transmission
Refinement method
Data / restraints / parameters
Goodness-of-fit on F2
Final R indices [I>2sigma(I)]
R indices (all data)
Absolute structure parameter
Largest diff. peak and hole
2427 [R(int) = 0.0317]
99.1 %
Semi-empirical from equivalents
1.00000 and 0.90324
Full-matrix least-squares on F2
2427 / 0 / 100
0.873
R1 = 0.0393, wR2 = 0.0772
R1 = 0.0674, wR2 = 0.0821
-1.2(9)
0.248 and -0.202 e.Å-3

Molecules 2008, 13
166
Table 2. Atomic coordinates ( x 104) and equivalent isotropic displacement parameters (Å2x 103)
for 3a,4,5,6,7,7a-Hexahydro-1H-isoindole-1,3(2H)-dione. U(eq) is defined as one third of the trace of
the orthogonalized Uij tensor.
Atoms
O(1)
O(2)
N
x
y
z
U(eq)________
36(1)
14804(1)
9681(1)
12075(1)
13916(1)
14594(1)
15963(1)
14865(1)
13199(1)
11673(1)
12617(1)
11271(1)
4204(1)
1315(1)
3090(1)
2996(1)
1165(1)
537(1)
35(1)
1252(1)
2592(1)
2005(1)
1573(1)
1644(1)
866(1)
-21(1)
36(1)
28(1)
C(1)
C(2)
C(3)
C(4)
C(5)
C(6)
C(7)
C(8)
27(1)
27(1)
34(1)
34(1)
-1214(1)
-391(1)
196(1)
1519(1)
201(1)
850(1)
1778(1)
2197(1)
33(1)
28(1)
27(1)
27(1)________
Table 3. Bond lengths [Å] for 3a,4,5,6,7,7a-Hexahydro-1H-isoindole-1,3(2H)-dione.
Bonds
Lengths______________________________________
O(1)-C(1)
O(2)-C(8)
N-C(8)
1.2089(7)
1.2185(9)
1.3718(8)
N-C(1)
1.3840(9)
N-H(0A)
0.8700
C(1)-C(2)
C(2)-C(3)
C(2)-C(7)
C(2)-H(2A)
C(3)-C(4)
C(3)-H(3A)
C(3)-H(3B)
C(4)-C(5)
C(4)-H(4A)
C(4)-H(4B)
C(5)-C(6)
C(5)-H(5A)
C(5)-H(5B)
C(6)-C(7)
C(6)-H(6A)
C(6)-H(6B)
C(7)-C(8)
C(7)-H(7A)
1.5091(8)
1.5241(10)
1.5419(9)
0.9900
1.5179(10)
0.9800
0.9800
1.5208(10)
0.9800
0.9800
1.5246(10)
0.9800
0.9800
1.5401(10)
0.9800
0.9800
1.5000(10)
0.9900_______________________________________

Molecules 2008, 13
167
Table 4. Bond Angles [°] for 3a,4,5,6,7,7a-Hexahydro-1H-isoindole-1,3(2H)-dione.
Atoms
Angles____________________________
C(8)-N-C(1)
113.19(5)
C(8)-N-H(0A)
123.4
C(1)-N-H(0A)
123.4
O(1)-C(1)-N
124.68(6)
O(1)-C(1)-C(2)
N-C(1)-C(2)
128.35(6)
106.88(5)
C(1)-C(2)-C(3)
C(1)-C(2)-C(7)
C(3)-C(2)-C(7)
C(1)-C(2)-H(2A)
C(3)-C(2)-H(2A)
C(7)-C(2)-H(2A)
C(4)-C(3)-C(2)
C(4)-C(3)-H(3A)
C(2)-C(3)-H(3A)
C(4)-C(3)-H(3B)
C(2)-C(3)-H(3B)
H(3A)-C(3)-H(3B)
C(3)-C(4)-C(5)
C(3)-C(4)-H(4A)
C(5)-C(4)-H(4A)
C(3)-C(4)-H(4B)
C(5)-C(4)-H(4B)
H(4A)-C(4)-H(4B)
C(4)-C(5)-C(6)
C(4)-C(5)-H(5A)
C(6)-C(5)-H(5A)
C(4)-C(5)-H(5B)
C(6)-C(5)-H(5B)
H(5A)-C(5)-H(5B)
C(5)-C(6)-C(7)
C(5)-C(6)-H(6A)
C(7)-C(6)-H(6A)
C(5)-C(6)-H(6B)
C(7)-C(6)-H(6B)
H(6A)-C(6)-H(6B)
C(8)-C(7)-C(6)
C(8)-C(7)-C(2)
C(6)-C(7)-C(2)
C(8)-C(7)-H(7A)
C(6)-C(7)-H(7A)
C(2)-C(7)-H(7A)
O(2)-C(8)-N
116.13(5)
102.49(5)
116.87(5)
106.9
106.9
106.9
113.50(6)
108.9
108.9
108.9
108.9
107.7
110.48(6)
109.6
109.6
109.6
109.6
108.1
110.47(6)
109.6
109.6
109.6
109.6
108.1
111.88(6)
109.2
109.2
109.2
109.2
107.9
107.52(6)
103.25(5)
113.23(6)
110.8
110.8
110.8
123.75(6)
O(2)-C(8)-C(7)
N-C(8)-C(7)
128.51(6)
107.61(6)___________________________

Molecules 2008, 13
168
Symmetry transformations used to generate equivalent atoms:
Table 5. Anisotropic displacement parameters (Å2x 103) for eb1a. The anisotropic
displacement factor exponent takes the form: -2π2[ h2 a*2U11 + ... + 2 h k a* b* U12 ]_________
U11
U22
U33
U23
1(1)
-1(1)
-1(1)
0(1)
2(1)
0(1)
-2(1)
-6(1)
-6(1)
4(1)
1(1)
U13
7(1)
U12__
-8(1)
-4(1)
-1(1)
-5(1)
-3(1)
4(1)
O(1)
O(2)
N
42(1)
38(1)
32(1)
31(1)
25(1)
25(1)
37(1)
36(1)
27(1)
29(1)
31(1)
28(1)
28(1)
20(1)
26(1)
24(1)
29(1)
30(1)
29(1)
23(1)
23(1)
27(1)
39(1)
42(1)
33(1)
23(1)
31(1)
47(1)
34(1)
34(1)
35(1)
28(1)
23(1)
14(1)
4(1)
C(1)
C(2)
C(3)
C(4)
C(5)
C(6)
C(7)
C(8)
-4(1)
-5(1)
5(1)
9(1)
1(1)
2(1)
2(1)
-4(1)
1(1)
1(1)
0(1)
-1(1)
-2(1)
______________________________________________________________________________
Table 6. Hydrogen coordinates ( x104) and isotropic displacement parameters (Å2x 103)
for 3a,4,5,6,7,7a-Hexahydro-1H-isoindole-1,3(2H)-dione.__________________________________
atom
x
y
z
U(eq)________
H(0A)
H(2A)
H(3A)
H(3B)
H(4A)
H(4B)
H(5A)
H(5B)
H(6A)
H(6B)
H(7A)
11488
15344
16922
16715
15798
14308
13755
12546
10610
11075
12791
4048
1059
1439
-452
-491
1057
-2233
-1569
-1213
595
2141
2237
716
34
32
40
40
40
40
40
40
34
34
32
1094
-462
-317
502
-380
983
535
780
2211
________________________________________________________________________________

Molecules 2008, 13
169
Table 7. Torsion angles [°] for for 3a,4,5,6,7,7a-Hexahydro-1H-isoindole-1,3(2H)-dione.________
Torsional Atoms
Atoms_______________________________________
C(8)-N-C(1)-O(1)
C(8)-N-C(1)-C(2)
O(1)-C(1)-C(2)-C(3)
N-C(1)-C(2)-C(3)
O(1)-C(1)-C(2)-C(7)
N-C(1)-C(2)-C(7)
C(1)-C(2)-C(3)-C(4)
C(7)-C(2)-C(3)-C(4)
C(2)-C(3)-C(4)-C(5)
C(3)-C(4)-C(5)-C(6)
C(4)-C(5)-C(6)-C(7)
C(5)-C(6)-C(7)-C(8)
C(5)-C(6)-C(7)-C(2)
C(1)-C(2)-C(7)-C(8)
C(3)-C(2)-C(7)-C(8)
C(1)-C(2)-C(7)-C(6)
C(3)-C(2)-C(7)-C(6)
C(1)-N-C(8)-O(2)
C(1)-N-C(8)-C(7)
C(6)-C(7)-C(8)-O(2)
C(2)-C(7)-C(8)-O(2)
C(6)-C(7)-C(8)-N
C(2)-C(7)-C(8)-N
171.80(6)
-11.56(7)
-32.24(10)
151.28(6)
-160.86(7)
22.66(7)
-80.77(7)
40.46(8)
-52.03(7)
61.99(7)
-59.17(7)
159.28(5)
45.88(7)
-24.88(6)
-153.05(6)
91.07(6)
-37.09(8)
178.41(6)
-5.39(7)
75.38(9)
-164.68(7)
-100.59(6)
19.36(7)
_______________________________________________________________________________
Symmetry transformations used to generate equivalent atoms:
Table 8. Hydrogen bonds for 3a,4,5,6,7,7a-Hexahydro-1H-isoindole-1,3(2H)-dione [Å and °].___
D-H...A
d(D-H)
0.87
d(H...A)
1.98
d(D...A)
<(DHA)_________
175.8
N-H(0A)...O(2)#1
2.8472(7)
_______________________________________________________________________________
Symmetry transformations used to generate equivalent atoms:
#1 -x+2,y+1/2,-z+1/2