Efficient synthesis of 16-28 membered macrocyclic crown amides via ring closing metathesis

Article abstract of DOI:10.1016/S0040-4020(03)01174-8

Ring closing metathesis of suitable diamides containing 1,ω-dienes led to efficient synthetic approaches towards macrocylic polyoxadiamides 1-18 with 16-28 membered ring sizes in good to excellent yields using Grubbs' catalyst.

Full text of DOI:10.1016/S0040-4020(03)01174-8

Tetrahedron 59 (2003) 7273–7282
Efficient synthesis of 16–28 membered macrocyclic crown amides
via ring closing metathesis
*
Yehia A. Ibrahim, Haider Behbehani, Maher R. Ibrahim and Rana N. Malhas
Department of Chemistry, Faculty of Science, Kuwait University, PO Box 5969, Safat 13060, Kuwait
Received 2 May 2003; revised 27 June 2003; accepted 25 July 2003
Abstract—Ring closing metathesis of suitable diamides containing 1,v-dienes led to efficient synthetic approaches towards macrocylic
polyoxadiamides 1–18 with 16–28 membered ring sizes in good to excellent yields using Grubbs’ catalyst.
q 2003 Elsevier Ltd. All rights reserved.
1. Introduction
using ring closing metathesis as the key macrocyclization
step.
The development of neutral ionophores useful in measure-
ments of intracellular as well as extracelluar cation
concentrations is a subject of considerable current interest.1
In general, crown compounds and azacrown compounds
constitute important macrocyclic groups in supramolecular
chemistry. They have been shown to exhibit important
applications including selective ion separation and detec-
tion, molecular recognition, catalysis, biological appli-
cations as well as many other interesting applications in
diverse fields of supramolecular chemistry.2,3 Of particular
interest are crown ethers incorporating amide groups, since
such groups modify the binding properties of the crown
compounds with respect to alkali metal ions.1,3 Moreover,
the number of ether oxygen, amide carbonyl groups, ring
size, lipophilic groups as well as other structural features
control the selectivity towards different ions.1,3 Synthetic
approaches towards such macrocycles usually suffer from
low yields, the loss of considerable amounts of the starting
precursors during the macrocyclization step due to polymer
formation, in addition to the need for high dilution
conditions and template effect.2 We and others reported
several moderate-to-good yielding synthetic approaches
towards macrocyclic crown-amides some of which showed
useful applications in ion selective electrodes.3 However,
previous synthetic approaches suffer from a considerable
decrease in yields as the ring size increases, in favor of
polymer formation.3f In the present investigation we report
an efficient synthetic approach towards crown diamides
with ring sizes extending from 16–28 membered rings,
Recently, ring closing metathesis (RCM) has been widely
used as a versatile technique for the formation of cyclic
olefins. It has been mainly applied for the formation of five-
to seven-membered carbocycles and heterocycles.4–8 Some
examples of macrocycle synthesis via RCM have been
reported.8–17 Several reviews dealing with RCM and illu-
strating its wide range of applications have recently been
published.18 Molybdenum alkylidene (Schrock catalysts)19
and ruthenium alkylidene (Grubbs’ catalysts)17,20 have
shown the best catalytic activity in the area of RCM. The
commercial availability and ease of handling of some of the
Grubbs’ catalysts (e.g. I) in addition to their tolerance of
normal reaction conditions and to a wide range of functional
groups attracted our attention for possible utility in the
synthesis of crown and azacrown macrocycles. In a recent
publication we demonstrated the versatile application of this
technique for the efficient atom economic synthesis of a
number of azacrowns, crowndiamides and crown-forma-
zans with cyclic olefinic function with variable ring sizes.21
Recently, isophthaloyl benzylic amide macrocycles
possessing an internal olefin were prepared and shown
to spontaneously self-assemble via interlocking to
give [2]catenanes in .95% yield.22 A special issue of
advanced synthesis and catalysis was devoted to olefin
metathesis.23
2. Results and discussion
Keywords: ring closing metathesis; 1,v-dienes; bis-N-allyl-o-
oxybenzamides; bis-o-allyloxybenzamides; bis-o-allyloxyanilides;
tetrabenzodiazapolyoxacycloalkenediones; pentabenzodiazapolyoxa-
cycloalkenediones.
In the present work we report our investigations (Scheme 1)
on the application of RCM with catalyst I as the key
macrocyclization step in the synthesis of macrocyclic
polyethers containing amide groups in the macrocyclic
ring. Results obtained in Table 1 provide reasonably good
*
Corresponding author. Tel.: þ965-9464215; fax: þ965-4816482;
e-mail: yehiaai@kuc01.kuniv.edu.kw
0040–4020/$ - see front matter q 2003 Elsevier Ltd. All rights reserved.
doi:10.1016/S0040-4020(03)01174-8

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Y. A. Ibrahim et al. / Tetrahedron 59 (2003) 7273–7282
Scheme 1.
synthetic procedure towards macrocyclic crowndiamides
with 16–22 membered rings. On the other hand, the results
obtained in Tables 2 and 3 provide an efficient atom
economic synthetic approach towards macrocylic polyox-
adiamides with 22–28 membered rings.
readily obtained by reacting the appropriate bisamine
dihydrochlorides 35–40 with o-allyloxybenzoyl chloride.
RCM of dienes 21–26 were investigated using different
ratios of the catalyst I (2.5–10 mol%) and the best yields
(40–60%) were obtained using 10 mol% of I in refluxing
CH2Cl2 for 3 h (Table 1). On the other hand RCM of the
dienes 29–34 and 41–46 (Tables 2 and 3) proceeded well
with 1–5 mol% of I in refluxing CH2Cl2 for 3 h to give
excellent yield of the corresponding macrocyclic products.
In all RCM reactions the progress of the reaction was
Schemes 2 and 3 illustrate our synthetic routes towards the
precursor 1,v-dienes 21–26, 29–34 needed for the RCM
synthesis of 1–6, 7–12. The starting N-allylsalicylamide
(19) and N-(o-allyloxyphenyl)salicylamide (27) were con-
verted into the desired 1,v-dienes via their potassium salt 20
and 28 upon treatment with the appropriate dihalo or
ditosylate compounds.
1
monitored by TLC and H NMR analysis where no further
increase in products was noticed after 3 h of reflux in
CH2Cl2. The larger amount of catalyst required in the RCM
of 21–26 might be due to the proximity effect of the CvO
On the other hand, the 1,v-dienes 41–46 (Scheme 4) were
Table 1. Synthesis of macrocytes 1–6
Entry
Substratea
Conditions/yield (%)a
Productb E:Z (%) ratio
1H NMR of E/Z products
J (Hz)
13C NMR
NH
NCH2
NCH2CHv
CH2CHv
1
2
3
4
5
21
22
23
24
25
a/5, b/10, c/40
a/5, b/15, c/47
a/5, b/25, c/50
a/12, b/25, c/50
a/10, b/25, c/50
1c
2c
3c
4c
5
5:1
6
3:1
7.34
7.86
7.90
8.16
8.22
8.30
7.74
7.74
4.10 (s)
4.16 (s)
4.17 (s)
4.15 (s)
4.12 (s)
4.12 (m)
3.92 (s)
3.92 (s)
6.04 (s)
6.00 (s)
5.98 (s)
5.91 (s)
5.86 (s)
5.69 (t)
5.58 (s)
5.41 (t)
42.3
39.9
41.2
41.5
41.3
37.1
40.3
36.0
3.9
4.2
6
26
a/13, b/26, c/60
(a) Substrate (0.2 mM), Grubbs’ catalyst I (2.5 mol%); CH2Cl2 (5 mL), reflux 3 h. (b) Substrate (0.2 mM), I (5 mol%); CH2Cl2 (5 mL), reflux 3 h. (c) Substrate
(0.2 mM), I (10 mol%); CH2Cl2 (5 mL), reflux 3 h.
a
b
c
1
The yield was determined by 400 MHz H NMR, unreacted starting substrates account for most of the remaining percent in each case.
All substrates and products were analyzed by 1H, 13C NMR, GC-MS, and gave satisfactory elemental analysis.
Only one isomer was detected most probably the E-isomer.

Y. A. Ibrahim et al. / Tetrahedron 59 (2003) 7273–7282
7275
Table 2. Synthesis of macrocytes 7–12
Entry
Substratea
Conditions/yield (%)a
Productb E:Z (%) ratio
1H NMR of E/Z products
J (Hz)
13C NMR
NH
OCH2
OCH2CHv
CH2CHv
1
2
3
4
5
6
29
30
31
32
33
34
a/78, b/100
a/81, b/100
a/80, b/100
b/90, c/100
a/80, c/100
a/100
7
5:1
8
5:1
9
5:1
10
3:1
11
3:1
12
3:1
10.40
10.35
10.19
10.19
10.29
10.37
10.20
10.22
10.32
10.26
10.56
10.75
4.69 (s)
4.84 (d)
4.60 (s)
4.71 (d)
4.63 (s)
4.81 (d)
4.75 (s)
4.86 (d)
4.76 (s)
4.83 (t)
4.15 (s)
4.52 (d)
6.36 (s)
6.18 (t)
6.22 (s)
6.04 (t)
6.26 (s)
6.08 (t)
6.28 (s)
6.14 (t)
6.17 (s)
6.03 (t)
5.84 (s)
6.85 (t)
68.5
65.1
69.0
64.1
68.9
63.4
68.9
64.7
69.4
65.5
69.5
65.4
5.0
3.7
3.7
3.7
2.9
3.2
(a) Substrate (0.2 mM), Grubbs’ catalyst I (1 mol%); CH2Cl2 (5 mL), reflux 3 h. (b) Substrate (0.2 mM), I (2 mol%); CH2Cl2 (5 mL), reflux 3 h. (c) Substrate
(0.2 mM), I (5 mol%); CH2Cl2 (5 mL), reflux 3 h.
a
The yield was determined by 400 MHz 1H NMR, unreacted starting substrates account for most of the remaining percent in each case.
b
1
All substrates and products were analyzed by H, 13C NMR, GC-MS, and gave satisfactory elemental analysis.
Table 3. Synthesis of macrocytes 13–18
Entry
Substratea
Conditions/yield (%)a
Productb E:Z (%) ratio
1H NMR of E/Z products
J (Hz)
13C NMR
CH2CHv
67.8
NH
OCH2
OCH2CHv
1
2
3
4
5
6
41
42
43
44
45
46
b/67, c/90
b/60, c/80
b/82, c/82
b/60, c/100
b/65, c/100
a, b/100
13
4:1
14
3:1
15
4:1
16
5:1
17
3:1
18
10.40
10.45
10.37
10.30
10.20
10.29
10.32
10.47
10.44
10.58
10.57
10.43
4.75 s
4.98 d
4.84 s
4.96 s
4.83 s
5.01 s
4.81 s
5.09 d
4.83 s
5.16 d
4.36 s
4.49 d
6.30 s
6.18 t
6.21 s
6.21 s
6.23 s
6.05 s
6.29 s
6.29 t
6.26 s
6.18 t
5.96 s
5.63 t
3.2
69.5
65.9
69.4
65.6
70.6
65.1
68.5
65.5
3.1
3.2
2.8
2:1
(a) Substrate (0.2 mM), I (1 mol%); CH2Cl2 (5 mL), reflux 3 h. (b) Substrate (0.2 mM), I (2 mol%); CH2Cl2 (5 mL), reflux 3 h. (c) Substrate (0.2 mM), I
(5 mol%); CH2Cl2 (5 mL), reflux 3 h.
a
The yield was determined by 400 MHz 1H NMR, unreacted starting substrates account for most of the remaining percent in each case.
b
1
All substrates and products were analyzed by H, 13C NMR, GC-MS, and gave satisfactory elemental analysis.
Scheme 2.
group which would chelate with ruthenium carbene, the
catalyst thus being sequestered in the form of unproductive
complex.16
occurred with only 1% catalyst (entries 6 Tables 2 and 3) in
which the two isomeric pentabenzo-24-crowndiamides 12
and 18 were obtained in almost quantitative yields.
From Table 3 it is clear that larger amount of the catalyst I
was needed in comparable entries to accomplish the systems
of macrocycles of similar ring sizes to those in Table 2.
Exception occurred in one case where olefin metathesis
The E:Z isomers of the olefinic crown diamides were readily
assigned and their ratios were determined from the 1H NMR
and 13C NMR spectra. The major products in all RCM
reactions were shown to be the E isomers with the

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Y. A. Ibrahim et al. / Tetrahedron 59 (2003) 7273–7282
Scheme 3.
Scheme 4.
characteristic 13C signal of the OCH2 (of the OCH22
CHvCHCH2O) which appears more downfield than that for
the corresponding Z isomer. On the contrary in 1H NMR the
OCH2 of E isomers appears as almost singlet and more
upfield than that of the Z isomer which splits into a doublet
with J¼3–5 Hz. Also, in 1H NMR the CHv of the E
isomers also appears as a singlet and further downfield than
that of Z isomer which appears as a triplet (Tables 2 and 3).
Similar observations were also, detected for the products
1–6 (Table 1) however, only the E isomers in the case of
compounds 1–4 were detected.
4. Experimental
4.1. General
Melting points are uncorrected. IR: (KBr) Shimadzu IR-740
spectrometer. 1H and 13C NMR: Bruker Avance 400
spectrometer. MS: GC/MS INCOS XL Finnigan MAT.
Microanalysis: LECO CHNS-932. Separation of reaction
products was performed using preparative HPLC WATER
PREP 4000 series with PDA detector WATER 2996 and
ABZþ column with a solvent mixture of acetonitrile and
water (70:30).
4.1.1. N-Allylsalicylamide 19. To a solution of allylamine
(5.7 g, 0.1 mol) in DCM (50 mL) at 08C was added TEA
(5 mL) followed by a dropwise addition of a solution of
salicoyl chloride (15.65 g., 0.1 mol) in DCM (50 mL) over a
period of 30 min. The reaction mixture was then kept
stirring at room temperature overnight. The mixture was
then diluted with DCM (50 mL) and washed with
hydrochloric acid (2 M, 200 mL), then twice with a
saturated solution of sodium carbonate and finally with
water, the organic layer was then dried over anhydrous
sodium sulfate and evaporated to dryness. The remaining
product was crystallized from petroleum ether (40–60) to
give 19 as colorless crystals, yield 74%; mp 50–528C
3. Conclusions
The present work demonstrates the efficient application
of RCM techniques for the synthesis of macrocyclic
crowndiamide derivatives with potential diverse appli-
cations in supramolecular chemistry and as starting
compounds for further synthetic transformations. The
examples of RCM presented here represent one of the best
macrocyclization reaction techniques for the synthesis of
crown compounds. This paper also, expands the utility of
RCM methodology and its application to the synthesis of
cyclic olefins of large ring sizes with different functional
groups.
1
(literature27 mp 51.58C). H NMR (CDCl3) d¼4.06 (s, 2H,

Y. A. Ibrahim et al. / Tetrahedron 59 (2003) 7273–7282
7277
NCH2CHv), 5.19 (m, 2H, CHvCH2), 5.91 (m, 1H,
CHvCH2), 6.83 (t, 1H, J¼8 Hz), 6.96 (d, 1H, J¼8 Hz),
7.08 (br, 1H, NH), 7.37 (dt, J¼8, 1 Hz), 7.51 (dd, 1H, J¼8,
1 Hz), 11.53 (br, 1H, OH).
J¼6.1 Hz, OCH2CH2), 5.11, 5.22 (2d, 4H, J¼10.4,
17.2 Hz, CH2vCH), 5.93 (m, 2H, CH2vCHCH2), 6.97
(d, 2H, J¼8 Hz), 7.12 (t, 2H, J¼8 Hz), 7.45 (dt, 2H, J¼8,
1.6 Hz), 8.20 (dd, 2H, J¼8, 1.6 Hz), 7.79 (br, 2H, NH). MS:
m/z (%)¼394 (20) [Mþ]. Anal. calcd for C23H26N2O4
(394.5): C, 70.03, H, 6.64, N, 7.10. Found C, 69.96, H, 6.61,
N, 7.27.
4.1.2. N-(o-Allyloxyphenyl)salicylamide 27. To a solution
of o-allyloxyaniline hydrochloride24 (18.45 g, 0.1 mol) in
DCM (50 mL) at 08C was added TEA (5 mL) followed by a
dropwise addition of a solution of salicoyl chloride
(15.65 g., 0.1 mol) in DCM (50 mL) over a period of
30 min. The reaction mixture was then kept stirring at room
temperature overnight. The mixture was then diluted with
DCM (50 mL) and washed with hydrochloric acid (2 M,
200 mL), then twice with a saturated solution of sodium
carbonate and finally with water, the organic layer was then
dried over anhydrous sodium sulfate and evaporated to
dryness. The remaining product was crystallized from
ethanol/water to give 27 as colorless crystals, yield 74%;
mp 84–868C. IR: 3287, 3070 (br), 2697, 2554, 1692, 1605,
1548, 1487, 1455, 1225, 1343, 1284, 1241, 1212, 1159,
1089, 1017, 994, 943, 902, 761, 746, 694. 1H NMR (CDCl3)
d¼4.69 (d, 2H, J¼4.9 Hz, OCH2CHv), 5.40, 5.48 (2d, 2H,
J¼10.4, 17.2 Hz, CHvCH2), 6.12 (m, 1H, CHvCH2), 6.95
(t, 2H, J¼8 Hz), 7.07 (d, 2H, J¼8 Hz), 7.12 (t, 1H, J¼8 Hz),
7.45 (t, 1H, J¼8 Hz), 7.52 (d, 1H, J¼8 Hz), 8.43 (d, 1H,
J¼8 Hz), 8.80 (s, 1H, NH), 12.17 (s, 1H, OH). Anal. calcd
for C16H15NO3 (269.3): C, 71.38, H, 5.61, N, 5.20. Found C,
71.00, H, 5.62, N, 5.24.
4.2.3. Compound 23. (From 20 and 1,4-dibromobutane),
yield 78%; mp 138–1408C (colorless crystals from EtOH).
IR: 3337, 3074, 2931, 2874, 1637, 1597, 1537, 1486, 1452,
1306, 1241, 1166, 1107, 1045, 980, 926, 846, 755, 655. 1H
NMR (CDCl3) d¼2.09 (br, 4H, OCH2CH2), 4.12 (d, 4H,
J¼5.2 Hz, NCH2CHv), 4.22 (br, 4H, OCH2CH2), 5.15,
5.27 (2d, 4H, J¼10.4, 17.2 Hz, CH2vCH), 5.96 (m, 2H,
CH2vCHCH2), 6.98 (d, 2H, J¼8.2 Hz), 7.12 (t, 2H, J¼
7.6 Hz), 7.46 (t, 2H, J¼7.8 Hz), 8.23 (d, 2H, J¼7.6 Hz),
7.91 (s, 2H, NH). MS: m/z (%)¼408 (100) [Mþ]. Anal.
calcd for C24H28N2O4 (408.5): C, 70.57, H, 6.91, N, 6.86.
Found C, 70.58, H, 6.86, N, 6.86.
4.2.4. Compound 24. (From 20 and diethyleneglycol
ditosylate), yield 75%; mp 93–958C (colorless crystals
1
from EtOH). H NMR (CDCl3) d¼3.86, 4.22 (2t, 4H, 4H,
J¼4.3, 4.3 Hz, (OCH2CH2O)2), 4.01 (t, 4H, J¼5.1 Hz,
NCH2CHv), 4.99, 5.15 (2d, 4H, J¼10.3, 17.2 Hz,
CH2vCH), 5.85 (m, 2H, CH2vCHCH2), 6.89 (d, 2H,
J¼8.2 Hz), 7.05 (t, 2H, J¼7.6 Hz), 7.38 (t, 2H, J¼7.6 Hz),
8.15 (d, 2H, J¼8.2 Hz), 8.04 (br, 2H, NH). LC/MS; m/z
(%)¼425 [Mþ1]. Anal. calcd for C24H28N2O5 (424.5): C,
67.91, H, 6.65, N, 6.60. Found C, 67.99, H, 6.65, N, 6.75.
4.2. Reaction of 19 and 27 with dihalo and ditosylates:
synthesis of 21–26 and 29–34. General procedure
Each of compound 19 and 27 (10 mmol) was added to a
solution of KOH (0.57 g, 10 mmol) in methanol (10 mL).
The mixture was then stirred at room temperature for 15 min
and the solvent was then removed in vacuo. The remaining
solid was washed with dry ether, collected, dried to give the
potassium salt 20 and 28. To the latter was added DMF
(10 mL) and the appropriate dihalo or ditosylates (5 mmol).
The reaction mixture was then heated under reflux for
15 min. The mixture was cooled, diluted with water (20 mL)
and the precipitate was collected, washed with cold water
and finally crystallized from the proper solvent.
4.2.5. Compound 25. (From 20 and triethyleneglycol
ditosylate), yield 70%; mp 80–828C (colorless crystals
from petroleum ether (60–80)). IR: 3266, 3075, 2978, 2902,
1651, 1633, 1599, 1559, 1484, 1451, 1388, 1347, 1310,
1291, 1270, 1239, 1228, 1164, 1106, 1007, 921, 757, 749,
1
685. H NMR (CDCl3): d¼3.62, 3.80, 4.17 (s, 2t, 4H, 4H,
4H, J¼4.4, 4.4 Hz, (OCH2CH2O)3), 4.04 (4H, t, J¼4.7 Hz,
NCH2CHv), 5.07, 5.20 (2d, 4H, J¼10.2, 17.4 Hz,
CH2vCH), 5.88 (m, 2H, CH2vCH), 6.86 (d, 2H,
J¼8 Hz), 7.02 (t, 2H, J¼8 Hz), 7.35 (t, 2H, J¼8 Hz), 8.14
(d, 2H, J¼8 Hz), 8.14 (br, 2H, NH). MS: m/z (%)¼468 (20)
[Mþ]. Anal. calcd for C26H32N2O6 (468.6): C, 66.65, H,
6.88, N, 5.98. Found C, 66.61, H, 6.47, N, 6.50.
4.2.1. Compound 21. (From 20 and 1,2-dibromoethane),
yield 70%; mp 150–1528C (colorless crystals from EteOH).
IR: 3324, 3079, 2956, 2891, 1637, 1600, 1538, 1491, 1472,
1451, 1309, 1239, 1166, 1112, 1052, 1036, 993, 916, 752,
665. 1H NMR (CDCl3) d¼3.92 (t, 4H, J¼6 Hz, NCH2CHv),
4.54 (s, 4H, OCH2CH2O), 4.69, 4.92 (2d, 4H, J¼10.1,
17.2 Hz, CH2vCH), 5.65 (m, 2H, CH2vCHCH2), 6.99 (d,
2H, J¼8 Hz), 7.16 (t, 2H, J¼8 Hz), 7.48 (dt, 2H, J¼8,
1.6 Hz), 8.24 (dd, 2H, J¼8, 1.6 Hz), 7.78 (br, 2H, NH). MS:
m/z (%)¼380 (100) [Mþ]. Anal. calcd for C22H24N2O4
(380.5): C, 69.46, H, 6.36, N, 7.36. Found C, 69.24, H, 6.38,
N, 7.51.
4.2.6. Compound 26. (From 20 and a,a-dibromo-o-
xylene), yield 80%; mp 90–928C (colorless crystals from
EtOH). IR: 3404, 3054, 2985, 2921, 1654, 1600, 1530,
1481, 1452, 1421, 1379, 1297, 1265, 1226, 1162, 1105,
1048, 996, 927, 738, 703. 1H NMR (CDCl3) d¼3.95 (t, 4H,
J¼5.3 Hz, NCH2CHv), 4.95, 4.97 (2d, 4H, J¼9.6, 18.8 Hz,
CH2vCH), 5.29 (s, 4H, OCH2Ar), 5.71 (m, 2H, CH2-
vCHCH2), 7.01 (d, 2H, J¼8 Hz), 7.12 (t, 2H, J¼7.6 Hz),
7.42–7.56 (m, 6H), 8.22 (d, 2H, J¼7.8 Hz), 10.28 (br, 2H,
NH). 13C NMR (CDCl3): d¼42.1, 68.9, 112.7, 116.0, 122.0,
122.1, 129.5, 130.0, 132.5, 132.9, 133.9, 134.1, 156.4,
164.9. MS: m/z¼456 (Mþ). Anal. calcd for C28H28N2O4
(456.6): C, 73.66, H, 6.18, N, 6.14. Found C, 73.70, H, 6.12,
N, 6.10.
4.2.2. Compound 22. (From 20 and 1,3-dibromopropane),
yield 75%; mp 140–1428C (colorless crystals from EtOH).
IR: 3331, 3076, 2946, 2924, 1635, 1600, 1537, 1489, 1465,
1450, 1411, 1310, 1241, 1161, 1110, 1062, 992, 976, 927,
760, 650. 1H NMR (CDCl3) d¼2.43 (quintet, 2H, J¼6.1 Hz,
OCH2CH2), 4.07 (m, 4H, NCH2CHv), 4.35 (t, 4H,
4.2.7. Compound 29. (From 28 and 1,2-dibromoethane),
yield 78%; mp 113–1158C (colorless crystals from MeOH).

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Y. A. Ibrahim et al. / Tetrahedron 59 (2003) 7273–7282
IR: 3358, 3069, 2937, 2868, 1664, 1599, 1535, 1479, 1452,
1421, 1331, 1290, 1235, 1161, 1133, 1090, 1045, 1013, 995,
917, 746, 674, 644. 1H NMR (CDCl3) d¼4.42 (d, 4H,
J¼5.1 Hz, OCH2CHv), 4.66 (s, 4H, OCH2CH2O), 5.19,
5.30 (2d, J¼10.8, 16.8 Hz, 4H, CH2vCH), 5.93 (m, 2H,
CH2vCHCH2), 6.76, 7.02, 7.12, 7.38, 8.18, 8.48 (m, 2H,
6H, 2H, 2H, 2H, 2H, ArH), 10.09 (s, 2H, NH). 13C NMR
(CDCl3): d¼67.93, 69.46, 111.45, 113.55, 118.11, 120.09,
121.41, 122.36, 123.30, 123.69, 128.16, 132.53, 132.81,
132.98, 147.25, 156.10, 162.64. MS: m/z (%)¼564 (100)
[Mþ]. Anal. calcd for C34H32N2O6 (564.6): C, 72.33, H,
5.71, N, 4.96. Found C, 72.12, H, 5.70, N, 5.18.
6.04 (m, 2H, CH2vCHCH2), 6.89, 7.03, 7.13, 7.44, 8.27,
8.59 (m, 2H, 6H, 2H, 2H, 2H, 2H, ArH), 10.29 (s, 2H, NH).
Anal. calcd for C38H40N2O8 (652.7): C, 69.92, H, 6.12, N,
4.29. Found C, 69.65, H, 6.02, N, 4.45.
4.2.12. Compound 34. (From 28 and a,a-dibromo-o-
xylene), yield 85%; mp 185–1868C (colorless crystals
from DMF). IR: 3331, 3064, 2923, 2870, 1650, 1600, 1542,
1478, 1454, 1423, 1340, 1312, 1287, 1255, 1220, 1160,
1135, 1089, 1045, 1020, 936, 897, 748, 682. 1H NMR
(CDCl3) d¼4.19 (d, 4H, J¼4.6 Hz, OCH2CHv), 5.04, 5.15
(2d, 4H, J¼10.4, 17.2 Hz, CH2vCH), 5.46 (s, 4H,
OCH2Ar), 5.72 (m, 2H, CH2vCHCH2), 6.80, 6.91, 7.01,
7.09, 7.21, 7.52, 8.23, 8.65 (m, 2H, 2H, 6H, 2H, 2H, 2H, 2H,
2H, ArH), 10.25 (s, 2H, NH). 13C NMR (CDCl3): d¼69.20,
69.25, 111.34, 113.12, 117.66, 120.62, 121.29, 121.93,
122.86, 123.61, 128.42, 128.75, 128.83, 132.51, 132.96,
133.02, 134.12, 147.16, 155.92, 163.12. MS: m/z¼640
(Mþ). Anal. calcd for C40H36N2O6 (640.6): C, 74.78, H,
5.66, N, 4.37. Found C, 74.88, H, 5.47, N, 4.52.
4.2.8. Compound 30. (From 28 and 1,3-dibromopropane),
YIELD 85%; mp 146–1488C (colorless crystals from
1
DMF). H NMR (CDCl3) d¼2.40 (quintet, 2H, J¼6 Hz,
OCH2CH2), 4.31 (t, 4H, J¼6 Hz, OCH2CH2), 4.44 (d, 4H,
J¼5.3 Hz, OCH2CHv), 5.14, 5.24 (2d, 4H, J¼10.4,
17.2 Hz, CH2vCH), 5.90 (m, 2H, CH2vCHCH2), 6.74,
6.83, 6.96, 7.03, 7.25, 8.16, 8.59 (m, 2H, 2H, 4H, 2H, 2H,
2H, 2H, ArH), 10.09 (s, 2H, NH). 13C NMR (CDCl3):
d¼28.70, 67.88, 69.55, 111.73, 112.79, 118.01, 120.76,
121.49, 121.81, 122.98, 123.65, 128.42, 132.44, 132.92,
133.03, 147.22, 156.06, 163.27. MS: m/z (%)¼578 (50)
[Mþ]. Anal. calcd for C35H34N2O6 (578.7): C, 72.65, H,
5.92, N, 4.84. Found C, 72.45, H, 5.52, N, 5.09.
4.3. Reaction of o-allyloxybenzoyl chloride with bis-
amines 35–40: synthesis of 41–46. General procedure
To a solution of each of the appropriate bis-amine
hydrochlorides 35–4025 (10 mmol) in DCM (10 mL) at
08C was added dropwise TEA (3 mL) followed by a
dropwise addition of a solution of o-allyloxybenzoyl
chloride26 (4.1 g, 21 mmol) in DCM (10 mL) over a period
of 30 min at 08C. The reaction mixture was then kept
stirring at room temperature overnight. The mixture was
then diluted with DCM (50 mL) and washed with
hydrochloric acid (2 M, 100 mL), then twice with saturated
sodium carbonate solution and finally with water. The
organic layer was then dried over anhydrous sodium sulfate
and evaporated to dryness. The remaining bis-anilides
41–46 were recrystallized from the proper solvent.
4.2.9. Compound 31. (From 28 and 1,4-dibromobutane),
yield 85%; mp 147–1488C (colorless crystals from DMF).
IR: 3348, 3074, 2975, 2929, 1661, 1597, 1534, 1478, 1453,
1334, 1291, 1231, 1132, 1090, 1045, 998, 942, 918, 748,
675. 1H NMR (CDCl3) d¼2.07 (s, 4H, OCH2CH2), 4.20 (s,
4H, OCH2CH2), 4.57 (d, 4H, J¼3.6 Hz, OCH2CHv), 5.20,
5.29 (2d, 4H, J¼10.5, 17.2 Hz, CH2vCH), 5.97 (m, 2H,
CH2vCHCH2), 6.86, 6.92, 7.03, 7.11, 7.41, 8.25, 8.64 (m,
2H, 2H, 4H, 2H, 2H, 2H, 2H, ArH), 10.19 (s, 2H, NH). Anal.
calcd for C36H36N2O6 (592.7): C, 72.95, H, 6.12, N, 4.73.
Found C, 72.75, H, 5.94, N, 4.73.
4.3.1. Compound 41. Yield 75%; mp 175–1778C (pale
yellow crystals from DMF/EtOH). 1H NMR (CDCl3)
d¼4.46 (dd, 4H, J¼3.2, 1.5 Hz, OCH2CHv), 4.50 (s, 4H,
OCH2CH2O), 5.06, 5.11 (2dd, 4H, J¼10.4, 1.5, 17.6,
1.4 Hz, CH2vCH), 5.72 (m, 2H, CH2vCHCH2), 6.77 (d,
2H, J¼8.4 Hz), 6.98 (m, 4H), 7.08 (m, 4H), 7.35 (dt, 2H,
J¼8.4, 1.6 Hz), 8.05 (m, 2H), 8.69 (m, 2H), 10.37 (s, 2H,
NH). 13C NMR (CDCl3): d¼67.09, 69.65, 111.02, 113.17,
117.50, 121.16, 121.44, 121.93, 122.05, 123.49, 128.80,
132.26, 132.41, 132.98, 147.16, 156.10, 163.28. Anal. calcd
for C34H32N2O6 (564.6): C, 72.33, H, 5.71, N, 4.96. Found
C, 72.05, H, 5.75, N, 5.28.
4.2.10. Compound 32. (From 28 and diethyleneglycol
ditosylate), yield 70%; mp 86–888C (colorless crystals from
MeOH). IR: 3335, 3068, 2917, 2881, 1658, 1598, 1537,
1477, 1454, 1424, 1335, 1288, 1251, 1220, 1161, 1132,
1
1089, 1045, 1017, 1002, 936, 745, 678. H NMR (CDCl3)
d¼3.84, 4.22 (2t, 4H, 4H, J¼4, 4 Hz, OCH2CH2OCH2-
CH22O), 4.56 (d, 4H, J¼4.5 Hz, OCH2CHv), 5.23, 5.37
(2d, 4H, J¼10.2, 17.2 Hz, CH2vCH), 6.02 (m, 2H,
CH2vCHCH2), 6.87 (m, 4H), 7.01 (m, 4H), 7.10 (t, 2H,
J¼7.6 Hz), 7.38 (t, 2H, J¼7.6 Hz), 8.25 (dd, 2H, J¼8,
1.6 Hz), 8.58 (d, 2H, J¼8.4 Hz), 10.27 (s, 2H, NH). 13C
NMR (CDCl3): d¼68.98, 69.29, 69.80, 111.94, 113.75,
118.11, 121.19, 121.53, 121.93, 123.13, 123.71, 128.63,
132.45, 132.93, 133.08, 147.63, 156.49, 164.00. MS; m/z
(%)¼608 (40) [Mþ]. C36H36 N2O7 (608.7): C, 71.04, H,
5.96, N, 4.64. Found C, 70.82, H, 5.84, N, 4.71.
4.3.2. Compound 42. Yield 78%; mp 128–1308C (colorless
crystals from EtOH). IR: 3354, 3068, 2968, 2946, 2881,
1659, 1598, 1533, 1480, 1451, 1331, 1288, 1252, 1219,
1133, 1090, 1048, 1015, 991, 926, 893, 750, 675. 1H NMR
(CDCl3) d¼2.33 (quintet, 2H, J¼6.2 Hz, OCH2CH2), 4.28
(t, 4H, J¼4.6 Hz, OCH2CH2), 4.67 (d, 4H, J¼5 Hz,
OCH2CHv), 5.22, 5.30 (2d, 4H, J¼10.4, 17.2 Hz,
CH2vCH), 5.98 (m, 2H, CH2vCHCH2), 6.87, 6.92, 6.97,
7.00, 7.14, 7.45, 8.29, 8.62 (m, 2H, 2H, 2H, 2H, 2H, 2H, 2H,
2H, ArH), 10.30 (s, 2H, NH). 13C NMR (CDCl3): d¼28.99,
65.12, 70.32, 111.31, 113.61, 118.27, 121.25, 121.47,
121.82, 122.68, 123.80, 128.52, 132.33, 132.46, 133.01,
4.2.11. Compound 33. (From 28 and triethyleneglycol
ditosylate), yield 70%; yellowish oil. IR: 3345, 3071, 2875,
1661, 1598, 1534, 1480, 1455, 1423, 1332, 1292, 1233,
1161, 1133, 1091, 1047, 1017, 930, 895, 753, 681. 1H NMR
(CDCl3) d¼3.49, 3.72, 4.42 (s, 2t, 12H, J¼5.2, 5.2 Hz,
OCH2(CH2OCH2)2CH2O), 4.62 (d, 4H, J¼5.2 Hz, OCH2-
CHv), 5.27, 5.39 (2d, 4H, J¼10.6, 17.6 Hz, CH2vCH),

Y. A. Ibrahim et al. / Tetrahedron 59 (2003) 7273–7282
7279
147.84, 156.34, 163.25. MS: m/z (%)¼578 (50) [Mþ]. Anal.
calcd for C35H34N2O6 (578.7): C, 72.65, H, 5.92, N, 4.84.
Found C, 72.55, H, 5.54, N, 4.86.
4.3.8. Compound 1. Mp 163–1658C, purified by ptlc
(eluent: DCM/EtOAc/petroleum ether (40–60), 1:2:2,
1
Rf¼0.65). H NMR (CDCl3): d¼4.10 (s, 4H, CH2N), 4.59
(s, 4H, CH2O), 6.04 (s, 2H, CHvCH), 6.96 (d, 2H,
J¼8.2 Hz), 7.13 (t, 2H, J¼7.6 Hz), 7.45 (t, 2H, J¼8.1 Hz),
8.05 (d, 2H, J¼7.6 Hz) 7.34 (br, 2H, NH). MS; m/z
(%)¼352 (40) [Mþ]. Anal. calcd for C20H20N2O4 (352.39):
C, 68.17, H, 5.72, N, 7.95. Found C, 67.95, H, 5.65, N, 8.20.
4.3.3. Compound 43. Yield 85%; mp 146–1488C (colorless
crystals from DMF). 1H NMR (CDCl3) d¼2.01 (s, 4H,
OCH2CH2), 4.15 (s, 4H, OCH2CH2), 4.69 (d, 4H, J¼4.7 Hz,
OCH2CHv), 5.20, 5.30 (2d, 4H, J¼10.6, 17.2 Hz,
CH2vCH), 5.98 (m, 2H, CH2vCHCH2), 6.91, 7.03, 7.10,
7.40, 8.27, 8.63 (m, 4H, 4H, 2H, 2H, 2H, 2H, ArH), 10.26 (s,
2H, NH). 13C NMR (CDCl3): d¼25.88, 68.08, 70.28,
111.10, 113.54, 118.20, 121.14, 121.31, 121.76, 122.73,
123.71, 128.49, 132.31, 132.41, 132.96, 147.61, 156.28,
163.22. Anal. calcd for C36H36N2O6 (592.7): C, 72.95, H,
6.12, N, 4.73. Found C, 72.80, H, 5.94, N, 4.73.
4.3.9. Compound 2. Mp 151–1538C, purified by ptlc
(eluent: DCM/EtOAc/petroleum ether (40–60), 1:1:1,
Rf¼0.7). IR: 3054, 2919, 2850, 1651, 1601, 1534, 1467,
1
1382, 1295, 1265, 1105, 1051, 1018, 739, 705. H NMR
(CDCl3): d¼2.45 (quintet, 2H, J¼6.4 Hz, CH2CH2O), 4.16
(s, 4H, CH2N), 4.34 (t, 4H, J¼6.4 Hz, CH2O), 6.00 (s, 2H,
CHvCH), 7.02 (d, 2H, J¼8.1 Hz), 7.15 (t, 2H, J¼7.6 Hz),
7.46 (t, 2H, J¼7.6 Hz), 8.18 (d, 2H, J¼8.1 Hz), 7.86 (br,
2H, NH). 13C NMR (CDCl3): d¼29.9, 40.7, 66.6, 114.2,
122.5, 122.9, 129.1, 132.3, 132.7, 156.3, 164.9. MS; m/z
(%)¼366 (20) [Mþ]. Anal. calcd for C21H22N2O4 (366.4):
C, 68.84, H, 6.05, N, 7.65. Found C, 68.64, H, 5.85, N,
7.56.
4.3.4. Compound 44. Yield 80%; mp 95–978C (colorless
crystals from MeOH). IR: 3332, 3067, 2916, 2874, 1656,
1597, 1535, 1478, 1454, 1333, 1287, 1252, 1221, 1161,
1133, 1092, 1046, 993, 946, 918, 751, 676. 1H NMR
(CDCl3) d¼3.84, 4.20 (2t, 8H, J¼4.6, 4.6 Hz, OCH2CH22
OCH2CH2O), 4.75 (d, 4H, J¼5 Hz, OCH2CHv), 5.23, 5.40
(2d, 4H, J¼10.4, 17.2 Hz, CH2vCH), 6.03 (m, 2H,
CH2vCHCH2), 6.88, 7.04, 7.39, 8.24, 8.66 (m, 4H, 6H,
2H, 2H, 2H, ArH), 10.39 (s, 2H, NH). MS; m/z (%)¼608
(80) [Mþ]. Anal. calcd for C36H36N2O7 (608.7): C, 71.04,
H, 5.96, N, 4.64. Found C, 70.82, H, 5.84, N, 4.71.
4.3.10. Compound 3. Mp 128–1308C, purified by ptlc
(eluent: DCM/EtOAc/petroleum ether (40–60), 1:1:1,
Rf¼0.8). IR: 3333, 3069, 2948, 1732, 1659, 1598, 1533,
1478, 1453, 1384, 1334, 1291, 1220, 1090, 1047, 1014, 994,
897, 751, 683. 1H NMR (CDCl3): d¼2.09 (s, 4H,
CH2CH2O), 4.17 (s, 4H, CH2N), 4.25 (s, 4H, CH2O), 5.98
(s, 2H, CHvCH), 6.99 (d, 2H, J¼8.4 Hz), 7.12 (t, 2H,
J¼7.6 Hz), 7.46 (t, 2H, J¼8.1 Hz), 8.23 (d, 2H, J¼8.0 Hz),
7.90 (br, 2H, NH). MS; m/z (%)¼380 (20) [Mþ]. Anal. calcd
for C21H22N2O4 (380.5): C, 69.46, H, 6.36, N, 7.36. Found
C, 69.36, H, 6.57, N, 6.94.
1
4.3.5. Compound 45. Yield 70%; yellowish oil. H NMR
(CDCl3) d¼3.57, 3.78, 4.20 (s, 2t, 12H, J¼4.6, 4.6 Hz,
OCH2(CH2OCH2)2CH2O), 4.83 (d, 4H, J¼5.2 Hz, OCH2-
CHv), 5.29, 5.38 (2d, 4H, 10.8, 17.8, CH2vCH), 6.09 (m,
2H, CH2vCHCH2), 6.94, 7.04, 7.12, 7.41, 8.27, 8.65 (m,
4H, 4H, 2H, 2H, 2H, 2H, ArH), 10.38 (s, 2H, NH). Anal.
calcd for C38H40N2O8 (652.7): C, 69.92, H, 6.12, N, 4.29.
Found C, 70.23, H, 5.85, N, 4.55.
4.3.11. Compound 4. Mp 163–1658C, purified by ptlc
(eluent: DCM/EtOAc/hexane 1:1:1, Rf¼0.75). IR: 3394,
3070, 2929, 2875, 1649, 1600, 1533, 1483, 1448, 1298,
4.3.6. Compound 46. Yield 80%; mp 134–1368C (colorless
crystals from EtOH). IR: 3368, 3326, 2979, 2892, 1656,
1599, 1538, 1479, 1453, 1334, 1290, 1252, 1217, 1088,
1047, 1004, 928, 895, 755, 739, 681, 664. 1H NMR (CDCl3)
d¼4.15 (d, 4H, J¼4.8 Hz, OCH2CHv), 5.06, 5.11 (2d, 4H,
J¼10.4, 17.2 Hz, CH2vCH), 5.28 (s, 4H, OCH2Ar), 5.68
(m, 2H, CH2vCHCH2), 6.88, 6.97, 7.12, 7.41, 7.51, 8.32,
8.66 (m, 6H, 2H, 2H, 4H, 2H, 2H, 2H, ArH), 10.49 (s, 2H,
NH). MS: m/z (%)¼640 (80) [Mþ]. Anal. calcd for
C40H36N2O6 (640.6): C, 74.78, H, 5.66, N, 4.37. Found C,
74.75, H, 5.73, N. Anal. calcd for 4.40.
1
1234, 1161, 1125, 1106, 1048, 960, 940, 753. H NMR
(CDCl3) d¼3.97, 4.29 (2t, 8H, J¼3.6, 3.6 Hz, OCH2
groups), 4.15 (s, 4H, NCH2CHv), 5.91 (br, 2H,
CHvCH), 6.95 (d, 2H, J¼8.2 Hz), 7.12 (t, 2H,
J¼7.6 Hz), 7.44 (dt, J¼8.1, 1.5 Hz), 8.24 (dd, 2H, 7.7,
1.5), 8.16 (s, 2H, NH). 13C NMR (CDCl3) (E-isomer):
d¼41.5, 67.7, 68.2, 112.6, 122.1, 128.3, 132.6, 132.7, 132.9,
156.7, 165.0. MS; m/z (%): 396 (30) [Mþ]. Anal. calcd for
C22H24N2O5 (396.5): C, 66.65, H, 6.10, N, 7.07. Found C,
66.39, H, 6.31, N, 6.62.
4.3.7. Ring closing metathesis of 21–26, 29–34 and
41–46: synthesis of 1–18. General procedure. A solution
of each of the substrates 21–26, 29–34 and 41–46
(0.12 mmol) in DCM (10 mL) and Grubbs’ Catalyst (I,
1–10 mg, ca. 1–10 mol% of the substrate) was heated
under reflux for 3 h (Tables 1–3). The reaction mixture was
then mixed well with silica gel (100–200 mm, 0.5 g) and
filtered, and the silica was extracted twice with DCM
(25 mL). The solvent was removed from the mixed DCM
extract in vacuo and the remaining reaction products were
analyzed by 1H NMR. The product mixture was purified and
separated either by column chromatography, preparative
thin layer chromatography, or preparative HPLC (cf.
Tables 1–3).
4.3.12. Compound 5. (E and Z): mp 134–1368C, purified
by ptlc (eluent: DCM/EtOAc/hexane 1:1:1, Rf¼0.65). IR:
3387, 3053, 2926, 1727, 1657, 1601, 1531, 1485, 1449,
1302, 1265, 1252, 1133, 1106, 1086, 1051, 925, 737, 703.
1H NMR (CDCl3) d¼3.72, 3.90, 4.27 (s, 2t, 12H, J¼4, 4 Hz,
OCH2 groups), 4.12 (m, 4H, NCH2CHv), 5.69 (t, 2H,
J¼3.9 Hz, Z-CHvCH), 5.86 (s, 2H, E-CHvCH), 6.94 (d,
2H, J¼8.2 Hz), 7.09 (t, 2H, J¼7.6 Hz), 7.42 (dt, 2H, J¼8.2,
1.5 Hz), 8.21 (dd, 2H, J¼8.0, 1.5 Hz), 8.22 (br, 2H, NH, E),
8.30 (br, 2H, NH, Z). 13C NMR (CDCl3) (E-isomer):
d¼41.3, 68.1, 69.5, 70.5, 112.7, 121.9, 128.7, 132.6, 132.7,
132.8, 156.7, 165.2; (Z-isomer): d¼37.1, 68.2, 69.6, 70.4,
112.6, 122.1, 129.3, 132.5, 132.7, 132.84, 156.7, 165.3. MS;
m/z (%): 440 (40) [Mþ]. Anal. calcd for C24H28N2O6

7280
Y. A. Ibrahim et al. / Tetrahedron 59 (2003) 7273–7282
(440.5): C, 65.44, H, 6.41, N, 6.36. Found C, 65.19, H, 6.49,
N, 6.12.
67.9, 68.9, 110.6, 112.4, 121.2, 121.5, 121.6, 122.4, 123.7,
1
128.4, 130.2, 132.8, 133.2, 147.4, 156.0, 163.4. H NMR
(CDCl3) (Z-isomer): d¼1.98 (br, 4H, CH2CH2O), 4.25 (br,
4H, OCH2CH2), 4.81 (d, 4H, J¼3.7 Hz, OCH2CHv), 6.08
(t, 2H, J¼3.7 Hz, CHvCH), 6.90–8.66 (m, 16H, ArH),
10.37 (s, 2H, NH). MS; m/z (%): 564 (100) [Mþ]. Anal.
calcd for C34H32N2O6 (564.6): C, 72.33, H, 5.71, N, 4.96.
Found C, 72.70, H, 5.70, N, 5.13.
4.3.13. Compound 6. (E and Z): mp 240–2428C, purified
by ptlc (eluent: DCM/EtOAc/petroleum ether (40–60),
1
1:1:1, Rf¼0.71). H NMR (CDCl3) (E-isomer): d¼3.92 (s,
4H, CH2N), 5.32 (s, 4H, CH2O), 5.58 (s, 2H, CHvCH),
7.13 (m, 4H), 7.45–7.59 (m, 6H), 8.21 (d, 2H, J¼7.6 Hz),
7.74 (br, 2H, NH), (Z-isomer): d¼5.23 (s, 4H, OCH2), 5.41
(t, 2H, J¼4.2 Hz, CHvCH). 13C NMR (CDCl3) (E-isomer):
d¼40.3, 68.7, 113.4, 122.3, 122.5, 128.8, 129.5, 130.0,
132.4, 132.7, 133.9, 156.9, 164.4, (Z-isomer): d¼36.0, 68.6,
112.5, 121.6, 122.0, 129.6, 129.9, 131.4, 132.5, 133.9,
134.3, 157.0, 164.7 MS; m/z (%)¼428 (50) [Mþ]. Anal.
calcd for C26H24N2O4 (428.5): C, 72.88, H, 5.65, N, 6.54.
Found C, 72.62, H, 5.85, N, 6.33.
4.3.17. Compound 10. (E and Z): mp 190–1928C, purified
by pHPLC (eluent: CH3CN/H2O, 7:3). IR: 3364, 3332,
3065, 3035, 2938, 2875, 1657, 1598, 1533, 1478, 1453,
1385, 1330, 1290, 1217, 1162, 1132, 1088, 1044, 1000, 966,
894, 750, 661. 1H NMR (CDCl3) (E-isomer): d¼3.97, 4.27
(2t, 8H, J¼5.8, 5.8 Hz, (OCH2CH2O)2), 4.75 (s, 4H,
OCH2CHv), 6.28 (s, 2H, CHvCH), 6.90–8.62 (m, 16H,
ArH), 10.20 (s, 2H, NH). 13C NMR (CDCl3) (E-isomer):
d¼68.5, 68.8, 69.00, 111.5, 113.2, 121.7, 121.72, 121.9,
122.8, 123.9, 128.5, 128.6, 132.7, 133.1, 147.8, 156.3,
4.3.14. Compound 7. (E and Z): mp 200–2028C, purified
by ptlc (eluent: MeOH/DCM/petroleum ether (40–60),
0.1:1:2, Rf¼0.31). IR: 3343, 3066, 2962, 1662, 1599, 1537,
1478, 1454, 1383, 1335, 1290, 1251, 1216, 1162, 1134,
1092, 1044, 1019, 797, 750, 682. 1H NMR (CDCl3)
(E-isomer): d¼4.69 (s, 8H, CH2OAr, OCH2CHv), 6.36
(s, 2H, CHvCH), 6.99–8.75 (m, 16H, ArH), 10.40 (s, 2H,
NH). 13C NMR (CDCl3): d¼65.30, 68.53, 110.75, 113.05,
120.52, 121.80, 122.54, 123.14, 123.71, 128.39, 129.45,
1
163.4. H NMR (CDCl3) (Z-isomer): d 4.02, 4.31 (2t, 8H,
J¼5.6, 5.6 Hz, (OCH2CH2O)2), 4.86 (d, 4H, J¼3.7 Hz,
OCH2CHv), 6.14 (t, 2H, J¼3.7 Hz, CHvCH), 6.98–8.65
(m, 16H, ArH), 10.22 (s, 2H, NH). 13C NMR (CDCl3) (Z
isomer): d¼67.7, 68.8, 69.2, 111.4, 113.4, 121.7, 121.8,
122.1, 122.8, 123.1, 128.5, 132.7, 133.1, 147.5, 156.4,
163.3. MS; m/z (%): 580 (60) [Mþ]; LCMS; m/z¼581
[Mþ1]. Anal. calcd for C34H32N2O7 (580.6): C, 70.33, H,
5.56, N, 4.82. Found C, 69.78, H, 5.60, N, 4.91.
1
132.71, 133.29, 147.34, 155.50, 162.83. H NMR (CDCl3)
(Z-isomer): d¼4.69 (s, 4H, OCH2 CH2O), 4.84 (d, 4H,
J¼5 Hz, OCH2CHv), 6.18 (t, 2H, J¼5 Hz, CHvCH),
6.99–8.64 (m, 16H, ArH), 10.35 (s, 2H, NH). 13C NMR
(CDCl3): d¼65.10, 65.37, 110.99, 113.31, 120.53, 121.97,
122.64, 123.14, 123.71, 128.83, 129.45, 132.85, 133.42,
147.34, 155.50, 162.83. MS; m/z (%)¼536 (100) [Mþ].
Anal. calcd for C32H28N2O6 (536.6): C, 71.63, H, 5.26, N,
5.22. Found C, 71.50, H, 5.34, N, 4.85.
4.3.18. Compound 11. (E and Z): mp 196–1988C, purified
by ptlc (eluent: EtOAc/DCM/hexane 1:1:2, Rf¼0.42). IR:
3164, 3061, 2990, 2916, 2848, 1736, 1444, 1376, 1270,
1246, 1045, 918, 849, 738, 704. 1H NMR (CDCl3)
(E-isomer): d¼3.51, 3.74, 4.22 (s, 2t, 12H, J¼5.6, 5.6 Hz,
OCH2CH2O), 4.76 (s, 4H, OCH2CHv), 6.17 (s, 2H,
CHvCH), 6.92–8.56 (m, 16H, ArH), 10.32 (s, 2H, NH).
1H NMR (CDCl3) (Z-isomer): d 3.52, 3.85, 4.36 (s, 2t, 12H,
J¼5.6, 5.6 Hz, OCH2CH2O), 4.83 (d, 4H, J¼2.9 Hz,
OCH2CHv), 6.03 (t, 2H, J¼2.9 Hz, CHvCH), 6.94–
8.54 (m, 16H, ArH), 10.26 (s, 2H, NH). LC/MS; m/z¼625
[Mþ1]. Anal. calcd for C36H36N2O8 (624.7): C, 69.22, H,
5.81, N, 4.48. Found C, 69.50, H, 5.68, N, 4.50.
4.3.15. Compound 8. (E and Z): mp 203–2068C, purified
by ptlc (eluent: EtOAc/DCM/petroleum ether (40–60),
1:2:3, Rf¼0.85). 1H NMR (CDCl3) (E-isomer): d¼2.52
(quintet, 2H, J¼6.1 Hz, OCH2CH2), 4.36 (t, 4H, J¼6.1 Hz,
OCH2CH2), 4.60 (s, 4H, OCH2CHv), 6.22 (s, 2H,
CHvCH), 6.89–8.60 (m, 16H, ArH), 10.19 (s, 2H, NH).
13C NMR (CDCl3): d¼29.11, 67.42, 69.00, 111.63, 113.16,
121.43, 121.78, 121.94, 122.81, 123.85, 128.47, 128.96,
4.3.19. Compound 12. (E and Z): mp 240–2428C, purified
by ptlc (eluent: EtOAc/DCM/hexane 5:2:5, Rf¼0.95). IR:
3328, 3069, 3035, 2938, 2881, 1657, 1599, 1541, 1479,
1455, 1408, 1336, 1293, 1257, 1219, 1162, 1133, 1091,
1
132.91, 133.21, 147.65, 156.33, 163.31. H NMR (CDCl3)
(Z-isomer): d¼2.53 (quintet, 2H, J¼6.1 Hz, OCH2CH2),
4.36 (t, 4H, J¼6.1 Hz, OCH2CH2), 4.71 (d, 4H, J¼3.7 Hz,
OCH2CHv), 6.04 (t, 2H, J¼3.7 Hz, CHvCH), 6.84–8.58
(m, 16H, ArH), 10.19 (s, 2H, NH). 13C NMR (CDCl3):
d¼29.11, 64.09, 66.90, 112.39, 112.61, 121.43, 121.78,
122.16, 122.50, 123.91, 128.53, 128.86, 132.47, 133.21,
147.40, 156.33, 163.25. MS; m/z (%)¼550 (100) [Mþ].
Anal. calcd for C33H30N2O6 (550.6): C, 71.99, H, 5.49, N,
5.09. Found C, 71.73, H, 5.65, N, 4.85.
1
1045, 1110, 965, 907, 753, 732, 675. H NMR (CDCl3)
(E-isomer): d¼4.15 (s, 4H, OCH2CHv), 5.35 (s, 4H,
OCH2Ar), 5.84 (s, 2H, CHvCH), 6.85–8.68 (m, 20H,
1
ArH), 10.56 (s, 2H, NH). H NMR (CDCl3) (Z-isomer):
d¼4.53 (d, 4H, J¼3.2 Hz, OCH2CHv), 5.44 (s, 4H,
OCH2Ar), 6.85 (t, 2H, J¼3.2 Hz, CHvCH), 6.84–8.77
(m, 20H, ArH), 10.75 (s, 2H, NH). 13C NMR (CDCl3): (E
and Z isomer) d¼65.36, 65.73, 65.90, 69.53. 111.18, 111.64,
113.39, 120.70, 121.09, 121.60, 121.66, 122.17, 122.33,
123.00, 123.75, 123.83, 126.77, 128.47, 128.50, 128.69,
132.45, 132.84, 133.19, 147.24, 156.14, 156.43, 163.07,
163.14. MS; m/z (%): 612 (60) [Mþ]. Anal. calcd for
C38H32N2O6 (612.7): C, 74.50, H, 5.26, N, 4.57. Found C,
74.65, H, 5.56, N, 4.62.
4.3.16. Compound 9. (E and Z): mp 238–2408C, purified
over short column of silca gel using DCM as an eluent. IR:
3347, 3069, 2965, 2886, 1656, 1597, 1532, 1478, 1455,
1331, 1293, 1252, 1217, 1135, 1089, 1041, 1015, 747, 678.
1H NMR (CDCl3) (E-isomer): d¼1.99 (br, 4H, CH2CH2O),
4.25 (br, 4H, OCH2CH2), 4.63 (d, 4H, J¼3.7 Hz, OCH22
CHv), 6.26 (t, 2H, J¼3.7 Hz, CHvCH), 6.91–8.68 (m,
16H, ArH), 10.29 (s, 2H, NH). 13C NMR (CDCl3): d¼25.5,
4.3.20. Compound 13. (E and Z): mp 224–2268C, purified

Y. A. Ibrahim et al. / Tetrahedron 59 (2003) 7273–7282
7281
by ptlc (eluent: EtOAc/DCM/petroleum ether (40–60) 2:1:3
1
121.9, 122.9, 123.7, 128.1, 128.9, 132.7, 133.0, 147.4,
156.4, 163.2; 13C NMR (CDCl3): (Z isomer) d¼65.6, 68.2,
69.6, 111.4, 112.7, 121.0, 121.7, 121.9, 122.6, 123.6, 128.7,
129.0, 132.5, 132.9, 147.3, 156.0, 163.1. MS; m/z (%): 580
(60) [Mþ]; LCMS; m/z¼581 [Mþ1]. Anal. calcd for
C34H32N2O7 (580.6): C, 70.33, H, 5.56, N, 4.82. Found C,
70.33, H, 5.58, N, 5.03.
Rf¼0.48). H NMR (CDCl3) (E-isomer): d¼4.40 (s, 4H,
OCH2CH2O), 4.75 (s, 4H, OCH2CHv), 6.30 (s, 2H,
CHvCH), 6.94–8.66 (m, 16H, ArH), 10.40 (s, 2H, NH).
1H NMR (CDCl3) (Z-isomer): d¼4.51 (s, 4H, OCH2CH2O),
4.98 (d, 4H, J¼3.2 Hz, OCH2CHv), 6.18 (t, 2H, J¼3.2 Hz,
CHvCH), 6.94–8.64 (m, 16H, ArH), 10.45 (s, 2H, NH).
13C NMR (CDCl3) (EþZ): d¼67.1, 69.6 (2 OCH2, OCH22
CHv), 111.1, 113.2, 117.5, 121.2, 121.4, 121.9, 122.0,
123.5, 128.8, 132.3, 132.4, 132.9, 147.2, 156.1, 163.3 (all
13C-signals of both E and Z isomers coincide except one in
the sp 2 region most probably the CHvCH). MS; m/z
(%)¼536 (30) [Mþ]. Anal. calcd for C32H28N2O6 (536.6):
C, 71.63, H, 5.26, N, 5.22. Found C, 71.54, H, 5.16, N, 4.87.
4.3.24. Compound 17. (E and Z): mp 182–1848C, purified
by ptlc (eluent: EtOAc/DCM/hexane 1:1:2, Rf¼0.6). 1H
NMR (CDCl3) (E-isomer): d¼3.64 (s, 4H, OCH2CH2O),
3.88, 4.21 (2t, 8H, J¼4.3, 4.3 Hz, (OCH2CH2O)2), 4.97 (s,
4H, OCH2CHv), 6.26 (s, 2H, CHvCH), 6.87–8.68 (m,
16H, ArH), 10.44 (s, 2H, NH). 1H NMR (CDCl3)
(Z-isomer): d 3.61, (s, 4H, OCH2CH2O), 3.89, 4.26 (2t,
8H, J¼4.6, 4.6 Hz, (OCH2CH2O)2), 5.16 (d, 4H, J¼3.2 Hz,
OCH2CHv), 6.18 (t, 2H, J¼3.1 Hz, CHvCH), 6.84–8.76
(m, 16H, ArH), 10.58 (s, 2H, NH). 13C NMR (CDCl3): (E
isomer) d¼68.18, 68.25, 69.26, 69.73, 111.43, 113.71,
121.01, 121.58, 121.88, 122.52, 123.59, 128.59, 128.79,
132.53, 132.87, 147.33, 156.24, 163.17. LCMS; m/z¼625
[Mþ1]. Anal. calcd for C36H36N2O8 (624.7): C, 69.22, H,
5.81, N, 4.48. Found C, 69.50, H, 5.68, N, 4.50.
4.3.21. Compound 14. (E and Z): mp 236–2388C, purified
by ptlc (eluent: EtOAc/DCM/petroleum ether (40–60),
1:1:3, Rf¼0.45). IR: 3342, 3069, 3035, 2930, 2881, 1656,
1598, 1535, 1478, 1453, 1378, 1333, 1291, 1250, 1214,
1133, 1090, 1048, 1003, 751, 674. 1H NMR (CDCl3)
(E-isomer): d¼2.36 (quintet, 2H, J¼6 Hz, CH2CH2O), 4.28
(t, 4H, J¼6 Hz, OCH2CH2), 4.84 (s, 4H, OCH2CHv), 6.21
(s, 2H, CHvCH), 6.92–8.70 (m, 16H, ArH), 10.37 (s, 2H,
1
NH). H NMR (CDCl3) (Z-isomer): d¼2.42 (quintet, 2H,
J¼6 Hz, CH2CH2O), 4.29 (t, 4H, J¼6 Hz, OCH2CH2), 4.96
(s, 4H, OCH2CHv), 6.21 (s, 2H, CHvCH), 6.92–8.70 (m,
16H, ArH), 10.30 (s, 2H, NH). 13C NMR (CDCl3): d¼28.63
(Z), 29.26 (E), 65.36 (E), 65.73 (Z), 65.90 (Z), 69.53 (E),
111.18, 111.64, 113.39, 120.70, 121.09, 121.60, 121.66,
122.17, 122.33, 122.96, 123.75, 123.83, 126.77, 128.47,
128.60, 128.69, 132.55, 132.84, 133.19, 147.24, 156.14,
156.53, 163.07, 163.14 (sp 2 carbons of both E and Z
isomers). MS; m/z (%): 550 (100) [Mþ]. Anal. calcd for
C33H30N2O6 (550.6): C, 71.99, H, 5.49, N, 5.09. Found C,
71.84, H, 5.47, N, 5.00.
4.3.25. Compound 18. (E and Z): mp 277–2798C, purified
by ptlc (eluent: EtOAc/DCM/hexane 1:1:1, Rf¼0.93). IR:
3342, 3068, 3036, 2930, 2878, 1655, 1598, 1536, 1478,
1453, 1384, 1334, 1290, 1251, 1215, 1161, 1133, 1090,
1
1049, 1001, 896, 750, 675. H NMR (CDCl3) (E-isomer):
d¼4.36 (s, 4H, OCH2CHv), 5.39 (s, 4H, OCH2Ar), 5.96 (s,
2H, CHvCH), 6.92–8.77 (m, 20H, ArH), 10.57 (s, 2H,
NH). 1H NMR (CDCl3) (Z-isomer): d¼4.49 (d, 4H,
J¼2.8 Hz, OCH2CHv), 5.35 (s, 4H, OCH2Ar), 5.64 (t,
2H, J¼2.8 Hz, CHvCH), 6.87–8.65 (m, 20H, ArH), 10.43
(s, 2H, NH). 13C NMR (CDCl3): (E and Z isomer) d¼65.46,
67.75, 67.93, 68.54. 110.80, 111.49, 112.67, 112.98, 120.88,
121.05, 121.45, 121.90, 121.97, 123.53, 123.41, 127.38,
127.65, 128.67, 128.77, 128.87, 132.78, 132.91, 133.03,
134.51, 146.89, 147.58, 155.87, 156.12, 162.94, 163.03.
MS; m/z (%): 612 (60) [Mþ]. Anal. calcd for C38H32N2O6
(612.7): C, 74.50, H, 5.26, N, 4.57. Found C, 74.33, H, 5.28,
N, 4.49.
4.3.22. Compound 15. (E and Z): mp 256–2588C, purified
by ptlc (eluent: EtOAc/DCM/petroleum ether (40–60),
2:1:3, Rf¼0.72). 1H NMR (CDCl3) (E-isomer): d¼2.03 (br,
4H, CH2CH2O), 4.16 (br, 4H, OCH2CH2), 4.83 (s, 4H,
OCH2CHv), 6.23 (s, 2H, CHvCH), 6.90–8.69 (m, 16H,
1
ArH), 10.20 (s, 2H, NH). H NMR (CDCl3) (Z-isomer):
d¼2.07 (br, 2H, CH2CH2O), 4.16 (br, 4H, OCH2CH2), 5.01
(s, 4H, OCH2CHv), 6.05 (s, 2H, 1H, CHvCH), 6.90–8.69
(m, 16H, ArH), 10.29 (s, 2H, NH). 13C NMR (CDCl3) (E
and Z isomer): d¼25.9, 68.1, 70.3, 110.6, 111.4, 118.2,
121.2, 121.22, 121.8, 123.7, 128.5, 129.1, 132.4, 133.0,
147.6, 156.3, 163.2. MS; m/z (%): 564 (50) [Mþ]. Anal.
calcd for C34H32N2O6 (564.6): C, 72.33, H, 5.71, N, 4.96.
Found C, 72.50, H, 6.10, N, 4.62.
Acknowledgements
The support of the University of Kuwait received through
research grant no. SC01/00 and the facilities of ANALAB
and SAF (grants no. GS01/01, GS03/01) are gratefully
acknowledged.
4.3.23. Compound 16. (E and Z): mp 198–2008C, purified
by pHPLC (eluent: CH3CN/H2O, 7:3). IR: 3342, 3067,
3033, 2932, 2877, 1656, 1598, 1538, 1478, 1455, 1333,
1292, 1253, 1219, 1163, 1133, 1091, 1050, 985, 967, 747,
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