Tetramethyldiamidophosphoric acid chloride mediated epoxide-diene conversion and steroidal aromatization

Article abstract of DOI:10.1016/S0040-4020(00)01002-4

The reaction of tetramethyldiamidophosphoric acid chloride with epoxides in the presence of a trace amount of water furnished 1,3-dienes in good yield. The conversion works with open chain and cyclic epoxides. A C-C bond cleavage reaction occurs if the epoxide contains a quaternary carbon. Application of this method to epoxy sterols afforded ring A aromatic steroids in good yield. The aromatization works via dienol-benzene rearrangements and is independent of the C-3 stereochemistry.

Full text of DOI:10.1016/S0040-4020(00)01002-4

TETRAHEDRON
Pergamon
Tetrahedron 57 (2001) 227±233
Tetramethyldiamidophosphoric acid chloride mediated
epoxide±diene conversion and steroidal aromatization
*
Ayhan S. Demir
Department of Chemistry, Middle East Technical University, 06531 Ankara, Turkey
Received 16 May 2000; revised 2 October 2000; accepted 19 October 2000
AbstractÐThe reaction of tetramethyldiamidophosphoric acid chloride with epoxides in the presence of a trace amount of water furnished
1,3-dienes in good yield. The conversion works with open chain and cyclic epoxides. A C±C bond cleavage reaction occurs if the epoxide
contains a quaternary carbon. Application of this method to epoxy sterols afforded ring A aromatic steroids in good yield. The aromatization
works via dienol-benzene rearrangements and is independent of the C-3 stereochemistry. q 2000 Elsevier Science Ltd. All rights reserved.
1. Introduction
While the deoxygenation of an epoxide to an ole®n is a well
known reaction,1 there is little by way of precedent2 for the
direct conversion of epoxides to dienes other than reactions
of selected epoxides with phosphates,3 phosphoranes,4 and
ethyl metaphosphates.5a Recently Hendrickson et al.
described the direct elimination of epoxides to dienes in
50±85% yields using phosphonium anhydrides.5b Pre-
liminary investigations of the scope and mechanism of
this epoxide±diene interconversion revealed that the
generality of the published methods is limited.6
2. Results and discussion
Although the HMPA-mediated dehydration of alcohols to
ole®ns is well known, the conversion of an epoxide to a
diene under similar conditions represented an interesting
According to Scheme 1, epoxycyclooctane (4a) was heated
at 140±1508C with 2 (5 ml per mmol of epoxide) in the
extension of this reaction. But studies of this epoxide to
presence of a trace amount of water, and the reaction was
diene interconversion show that the generality was also
conveniently monitored by GLC using internal standards.
limited. The suggested mechanism ascribes that tetra-
methyldiamidophosphoric acid (1), formed by hydrolysis
After 30 min no more starting material was present. The
crude reaction mixture was worked up by dilution with
of HMPA, could have an important role.7a±f
water and was extracted with ether or hexane. The analysis
of the product by NMR, IR and GLC indicated that the
The aim of this work was to generate tetramethyldiamido-
epoxide was effectively dehydrated to give 1,3-cyclo-
phosphoric acid (1) and react it with epoxides. For this
octadiene (5a) in 92% yield. Repeating this reaction under
purpose tetramethyldiamidophosphoric acid chloride (2)
was chosen as a starting material according to the procedure
anhydrous conditions with distilled 2 under argon gave only
a trace amount of diene 5a. This result indicated that water
was necessary for this conversion.
of Heath et al.8 Le Roux et al.9 showed that this compound is
stable in acidic medium (JP±Meˆ9 Hz) but gives octamethyl-
diamidopyrophosphate (3) (JP±Meˆ10.3 Hz) in alkali
medium. The free acid 1 should be produced from its
chloride 2 under Heath's conditions.8
Keywords: epoxides; dienes; steroid and sterols; aromatization.
* Tel.: 190-312-2103242; fax: 190-312-210-1280;
e-mail: asdemir@metu.edu.tr
Scheme 1.
0040±4020/01/$ - see front matter q 2000 Elsevier Science Ltd. All rights reserved.
PII: S0040-4020(00)01002-4

228
A. S. Demir / Tetrahedron 57 (2001) 227±233
Table 1. Tetramethyldiamidophosphoric acid chloride mediated epoxide±diene conversion
aCommercially available epoxides are used.
bcis-trans Mixture.
cThe yields are determined by GLC (column: HP-1, detector: FID, initial: 1208C, oven: 1508C, ®nal: 2008C) using internal standards.
dPart of the ester is hydrolyzed during the conversion.
ecis±cis Isomer.
fMixture of isomers (92:8).
gIsolated yield of the isomeric mixture.
The commercial cyclododecane epoxide, a mixture of cis
and trans isomers (2:1) (4b), is also dehydrated using the
same procedure as for 4a.10 The cyclododecadiene (5b) was
isolated in 74% yield as a mixture of isomers (GLC: 92:8,
1E, 3Z is the major isomer).
before isomerization was detected when the reaction was
stopped after 10 min and the crude product was analysed
by 1H NMR spectrum (d 4.76 CH2 protons) and
GC±MS.11a,12 From the same crude mixture the compounds
7 was also detected using GC±MS (4±5%, M1 132) and
characterised as 2,4-DNP derivative.11b
The deoxygenation of the open chain epoxide methyl oleate
epoxide6 (4c) affords an isomeric mixture of 1,3-diene 5c in
76% yield. Under similar conditions cyclopentene oxide
(4d) furnished dimeric cyclopentadiene (5d) in 52% yield
and the crude product contains unde®ned polymeric
material. Heating of 4-vinyl-1-cyclohexene-1,2-epoxide
(4e) with 2 furnished ethylbenzene (5e) in 78% yield and
limonene oxide (4f) afforded 1-isopropyl-4-methyl
benzene (5f) in 76% yield after epoxide±diene conversion
and isomerization of the triene to the aromatic ring.
Triene 5-isopropenyl-2-methyl-1,3-cyclohexadiene (6)
Interestingly, 1-isopropyl-4-methylbenzene (5f) was also
obtained from deoxygenation of a-pinene oxide (4g) in
71% yield. During this conversion, C±C bond cleavage
and elimination, followed by isomerization, occurs to give
benzene derivative 5f via formation of stable carbonium
ions. Treatment of (20R)-5a,6a-epoxycholestane (4h)
with 2 as described above afforded a mixture of products.
The products are identi®ed as cholesta-4,6-diene (5g)
(major product) and cholesta-3,5-diene (5h) (minor
product)(GLC 5:1 mixture, mp 78±798C, total yield 73%).

A. S. Demir / Tetrahedron 57 (2001) 227±233
229
Scheme 2.
The chromatographic separation of the isomers was
unsuccessful. The product mixture was characterised using
NMR spectroscopy (d 5.38±5.98 ole®nic protons) and GLC
(comparing of the mixture with authentic samples12). Only
one reaction is described in the literature for the formation
of 3,5- and 4,6-cholestadiene in 1:1 ratio starting from
isomeric 5,6-epoxycholestanes by using aluminum
alkoxides.13,14 The deoxygenation reactions of epoxides
with 2 in the presence of a trace amount of water are
summarised in Table 1.
tion by the phosphonate departing would be followed by a
series of elimination to give the double bonds.
As shown in the following illustrative examples the simple
elimination process with secondary alcohols with tetra-
methyldiamidophosphoric acid chloride (2) for 1±4 h in
the presence of trace amount of water afforded ole®ns in
good yields (yields by distillation or chromatography):
This simple conversion of alkenes through their epoxides to
the dienes has been applied to epoxy sterols in order to
prepare ring A aromatized steroids. Monoaromatic steroids
are of considerable interest both from a biological and
chemical viewpoint. They represent one of the important
classes of naturally occurring, biologically active
compounds, namely the estrogens that comprise the female
sex hormones. The estrogens enjoy an extensive range of
use in therapy. Considerable effort has been directed
towards the synthesis of estrogens and other analogues of
ring A aromatic steroids.15 Investigation of possible routes
to the synthesis of estrogenic hormones has led to numerous
approaches to access the A ring aromatic skeleton.16±23
1. cyclohexanol!cyclohexene (55%)
2. menthol!3-menthene and 2-menthene (61 and 23%)
3. cholesterol!cholesta-3,5-diene (85%)
4. borneol!camphene (77%)
5. cis-1,5-cycloocatanediol!cis, cis-1.5-cyclooctadiene
(82%)
With this additional information we considered that in the
dehydration reaction with tetramethyldiamidophosphoric
acid chloride (2) in the presence of trace amount of water
the formation of tetramethyldiamidophosphoric acid (1) and
HCl is the key step. As suggested in Scheme 2 the conversion
may work via monophosphonate, and or bis-phosphonate
intermediates. No cyclic 1,3,2-dioxaphospholan is detected
during the reactions.
The dienol±benzene aromatization reaction of ring A of the
steroids is one example of a more general class of steroid
aromatization reactions which requires two double bond
equivalents and a carbonium ion source in order to
proceed.24,25 The cationic spiro intermediate, which is char-
acteristic of the dienol±benzene rearrangement, may be
derived from a range of compounds including the 3b-mesyl-
oxy-5a-6a-epoxides. Our initial attention was focused on
the reaction of tetramethyldiamidophosphoric acid chloride
with epoxy sterols for obtaining ring A aromatization via
dienol-benzene rearrangement. The methanesulfonate of
In the reaction of a-pinene oxide (4g) with 2, epoxide ring
opening, followed by polarisation of a C-2a±O bond (8) and
axial cleavage mode of reaction via formation of carboca-
Scheme 3.

230
A. S. Demir / Tetrahedron 57 (2001) 227±233
aromatization occurred (during the ®rst 5±10 min the triene
is the major product). This showed that the aromatization
and migration of the methyl group may proceed via forma-
tion of the 2,4,6-triene.
Heating of the methanosulfonate of 3b-hydroxyl-5,6-epoxy
cholestane (9a) with tetramethyldiamidophosphoric acid
chloride (2) for 3 h (the reaction was monitored by TLC
using reference compounds) furnished aromatized
compound 10a as a major product in 66% yield after puri-
®cation. Under similar conditions 3b-methanosulfonate of
5a,6a-androstan-17-one (9d) and stigmasterol (9f) gave A
ring aromatization products 4-methylestra-1,3,5(10)-triene-
17-one (10b) and 4-methylstigmast-1,3,5(10),22-tetraene
(10c) in 71% and 73% respectively (Scheme 4).
Scheme 4.
3b-hydroxyl-5a,6a-epoxy cholestane (9a) and tetramethyl-
diamidophosphoric acid chloride (2) was heated with a trace
amount of water and the reaction was monitored by TLC.
After 2 h almost all of the starting material was consumed
and two UV active spots were observed with Rf values of
0.64 and 0.60. The fractions were separated by column
chromatography and identi®ed as 4-methyl-19-nor-
cholesta-1,3,5(10)-triene (10a, 45%)26 and cholesta-2,4,6-
The sterols are converted to the 5a,6a-epoxide derivatives
with m-chloroperbenzoic acid.27,30 The methanesulfonate of
5a,6a-epoxy sterols are prepared using methane sulfonyl
chloride and triethylamine according to the literature
procedure.31,32
triene (11, 16%).27 The H NMR spectrum of 10a showed
the migration of C-19 (methyl group) from C-10 to C-4
giving a singlet at 2.18 ppm (3 protons) and three aromatic
protons between 7.01±7.19 as multiplet (Scheme 3).
1
The conversion of methanosulfonates 9a, 9d and 9f to the
aromatized derivatives involved the thermal elimination of
methanesulfonic acid, epoxide±diene conversion and proto-
tropic rearrangements. That the methanesulfonic acid was
not essential for the conversion of the epoxide to the diene
and subsequent aromatization was demonstrated by the
reaction of 9b, 9c, 9e, and 9g in tetramethyldiamidopho-
sphoric acid chloride, which also afforded the expected
ring A aromatization products 10a, 10b and 10c in one
step and good yields as shown in Scheme 4. Treatment of
3a-hydroxy-5a,6a-epoxycholestane 9c with tetramethyl-
diamidophosphoric acid chloride gave 4-methylestra-
Assignment of the 2,4,6-triene 11 structure rather than the
isomeric 1,3,5-triene rested on the analysis of the NMR
1
spectrum (1H, 13C, DEPT, COSY). The H NMR spectrum
shows two spin system for H-6 and H-7, three spin system
for H-2, H-3 and H-4 consistent only with 2,4,6-triene. In
addition, the allylic H-1 ethylene signals in COSY NMR of
2,4,6-triene 11 showed only geminal and allylic coupling to
H-2. The chemical shift of d 0.95 for the C-19 angular
methyl group in 11 was consistent with the values reported
in the literature for related systems.28,29 Monitoring of the
reaction by GLC showed that the triene formed ®rst then
Table 2. Ring A aromatization of 5a,6a-epoxy-sterols
Starting materiala 9
C-3 Stereochem.
R1
R2
Reaction time (h)
3
Product 10
Yield (%)
66
ab
b
CH3SO22
ai
bc
cd
b
a
H
H
4
4
a
a
63
64
de
ef
b
b
CH3SO22
H
O
O
3
4
bj
b
71
70
fg
b
b
CH3SO22
3
3
ck
73
69
g2h
H
c
a The starting materials are synthesized according to the literature procedure and the spectroscopic data are in agreement with the published values.
b Mp 148±1508C (Lit.32 146±1508C.
c Mp 143±1458C (Lit.30 144±1458C).
d Mp 124±1258C (Lit.33 124±1258C).
e Mp 168±1708C (Lit.34 168±1728C).
f Mp 228±2298C (Lit.35 229±2308C).
g Mp 157±1608C (Lit.21 162±1648C).
h Mp 147±1508C (Lit.21 149±1518C).
i Mp 48±498C (Lit.26a 498C).
j Mp 190±1928C (Lit.36a 191±1928C).
k Mp 115±1168C (Lit.21 116±1188C).

A. S. Demir / Tetrahedron 57 (2001) 227±233
231
Aromatization of 3-substituted 5a,6a-epoxides proceeds
with hydroxy and methanosulfonate and is independent of
the C-3 stereochemistry. This process offers an attractive
alternative to other multistep procedures.
4. Experimental
All reagents were of commercial quality and reagent quality
solvents were used without further puri®cation. IR spectra
were determined on a Philips model PU9700 spectrometer.
1H NMR spectra were determined on a Bruker 400 MHz FT
spectrometer. GLC analyses were determined on a HP 5890
gas chromatograph. Mass spectra were obtained on
VGTrio2 spectrometer at ionisation energy of 70 eV.
4.1. Reactions with tetramethyldiamidophosphoric acid
chloride. General procedure
1 mmol of epoxide was dissolved in 5 ml tetramethyl-
diamidophosphoric acid chloride and to this solution was
added 1±2 drops of water. The mixture was heated at 140±
1508C and then diluted with 5 ml of water while still warm
and extracted with 30 ml of ether or hexane. Organic layer
was washed with 5 ml of 1N HCl solution and brine, dried
over MgSO4. Evaporation of solvent gave the 1.3-diene.
GLC conditions (Inlet temp. 1508C, oven 908C, detec.
temp. 2008C).
Scheme 5.
4.2. Representative examples
1,3,5(10)-triene-17-one (10a) in 64% yield. This experiment
showed that the aromatization reaction is independent of the
C-3 stereochemistry. The results of the ring A aromatization
are summarized in Table 2.
4.2.1. 1,3-Cyclooctadiene (5a). According to the general
procedure, the reaction of cyclooctene oxide (126 mg,
1 mmol) afforded cyclooctane-1.3-diene in 92.5% yield
(GLC; column: HP-1, detector: FID, initial: 1208C, oven:
1508C, ®nal: 2008C).
A proposed mechanism for this tetramethyldiamido-
phosphoric acid chloride mediated reaction of epoxy sterols
is shown in Scheme 5. The initial reaction of epoxide with
tetramethyldiamidophosphoric acid involves proton transfer
and ring opening. A series of elimination reactions
(elimination of methanesulfonate, water and tetramethyl-
diamidophosphate) and prototropic rearangements furnishes
the 2,4,6-triene. The 2,4,6-triene would then isomerize to
the 1,3,5-triene and could then be protonated at C-6 to
generate the spiro intermediate characteristic of the
dienol-benzene rearrangements.18±20
4.2.2. 1,3-Cyclododecadiene (5b). According to the general
procedure, cyclododecane epoxide (4b) (182 mg, 1 mmol)
gave cyclododecadiene (5b) (122 mg, 74%) as a colourless
liquid after puri®cation of the crude product (PTLC, silica
gel 60, EtOAc/ hexane 1:20). IR(TF): 2950±2850, 1455,
1366 cm21 1H NMR (CDCl3): d 1.11±1.73 (m,12, 6
.
CH2), 2.01±2.48 (m, 4, 2 allyl. CH2), 5.31±5.78 (m, 2,
CH±CH2±), 6.12± 6.47 (m, 2, CH±CH±CH±CH). 13C
NMR (CDCl3): d 21.92, 22.18, 22.52, 22.62, 22.72, 23.07,
23.46, 23.60, 23.76, 23.81, 24.16, 24.47, 24.98, 25.28,
25.90, 26.97, 27.21, 27.97, 28.97, 29.7, 127.10, 128.26,
129.50, 129.60, 130.27, 131.56, 134.2. GC±MS (isomeric
mixtures, 92:8): (m/z) (%bp) 164 (M1), 149, 135, 121, 107,
91, 79(bp), 67, 55. The structural data agree with those of
lit.5b,10
3. Conclusions
In conclusion, we have developed an ef®cient and con-
venient route for epoxide±diene conversion. These results
show that epoxide±diene conversion occurs when epoxides
are treated with tetramethyldiamidophosphoric acid
chloride (2). The conversion works with open chain and
cyclic epoxides. A C±C bond cleavage reaction occurs if
the epoxide contains a quaternary carbon. The formed
polyenes are isomerizing to the most stable structures. The
reaction is simple, tetramethyldiamidophosphoric acid
chloride (2) is commercially available and the yields are
good Application of this method to the epoxy sterols
furnished A ring aromatized steroids in good yields. The
aromatization works via formation of a 2,4,6-triene.
4.2.3. Reaction of 5a,6a-epoxycholestane with 2: the
synthesis of cholesta-4,6-diene (5g) and cholesta-3,5-
diene (5h). In accordance with the general procedure the
mixture of 5a,6a-epoxycholestane 4h (3.3 g, 8 mmol) and 2
was re¯uxed for 4 h (checked by TLC. Petroleum ether:
ether 10:1). The mixture was cooled and extracted with
ether three times and was washed with water and
NaHCO3 solution three times and dried over anhydrous
MgSO4. The solution was ®ltered, concentrated and chro-
matographed on silica gel (Petroleum ether±ether 10:1) to

232
A. S. Demir / Tetrahedron 57 (2001) 227±233
give a mixture of 5g and 5h (2.54 g, 73%) (5:1; GLC, OV
101 capillary column, 908C) as a colourless solid, mp 77±
798C. H NMR (CDCl3): d 0.66, 0.71, 0.82, 0.89 (methyl
protons), 5.38±5.98 (vinylic protons). The structural data
agree with those of literature.12
128.3, 131.2 (5 ole®nic C±H),143.2(one ole®nic quatenary
carbon). The structural data agree with those of literature.26
1
4.5.2.
4-Methylestra-1,3,5(10)-triene-17-one
(9b).36
1H NMR (CDCl3): d 0.93 (s, 3H, C-18 CH3), 2.24 (s, 3H,
C-19 CH3), 7.03, 7.16, and 7.23 (3 m, 3H, Ar-H). 13C NMR
(CDCl3): d 13.6, 20.2, 21.5, 25.7, 26.3, 26.8, 32.1, 35.8,
37.3, 45.1, 47.6, 51.2, 123.4, 125.7, 128.1, 134.8, 136.6,
139.9, 220.1. The structural data agree with those of litera-
ture.36
4.3. General procedure for epoxidation of sterols:30±35
To 25 mmol of sterol in 300 ml of CHCl3 at 08C was added
40 mmol of m-chloroperbenzoic acid portionwise. The
mixture was stirred at 80C for 1 h and ®ltered. The ®ltrate
was washed successively with saturated NaHCO3, H2O, and
brine. The solution was dried over anhydrous MgSO4 and
the crude product was puri®ed by column chromatography
or crystallization.
4.5.3. (20R, 22E,24S)-4-Methylstigmast-1,3,5(10),22-tetra-
ene (10c).21 1H NMR (CDCl3): 0.74 (s, 3H, C-18 CH3), 0.81
(t, Jˆ7.2 Hz, 3H, C-29 CH3), 0.83 (d, Jˆ6.5 Hz, 3H, CH3),
0.89 (d, Jˆ6.5 Hz, 3H, CH3), 1.03 (d, Jˆ6.5 Hz, 3H, C-21
CH3), 2.22 (s, 3H, C-4 CH3), 4.92-5.23 (m, 2H, vinylic H),
6.98±7.25 (m, 3H, Ar-H). The structural data agree with
those of literature.21
4.4. General procedure for methanesulfonate of epoxy-
sterols:21,32,34
To a 20 mmol solution of epoxysterol in 60 ml of CH2Cl2 at
08C under argon atmosphere was added 60 mmol of Et3N
followed by slow addition of 25 mmol of methanesulfonyl
chloride. The mixture was stirred for 1 h at 08C and diluted
with cold water. The solution was extracted twice with
100 ml of CH2Cl2. The organic layer was washed succes-
sively with H2O to neutral pH and with brine. The solution
was dried over MgSO4, ®ltered, and concentrated to afford
crude product which was chromatographed on silica gel
using 3:1 hexane±EtOAc.
Acknowledgements
This research was supported by the Middle East Technical
University (AFP- 1999) and the Turkish State Planning
Organisation (DPT) (400 MHz NMR instrument).
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4.5. Reactions with tetramethyldiamidophosphoric acid
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(10 equiv.) tetramethyldiamidophosphoric acid chloride
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5 ml of water while still warm and extracted with 25 ml of
ether. The ether layer was washed with 10 ml of 1N HCl
solution and brine, dried over MgSO4. Evaporation of
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fused silica gel capillary column (15 M).
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4.5.1. Synthesis of 4-methyl-19-norcholesta-1,3,5(10)-
triene (10a) and cholesta-2,4,6-triene (11). According to
the general procedure 9a (480 mg,1 mmol) afforded after
2 h re¯ux and chromatographic separation (EtOAc: hexane
1:5) of 10a (164 mg, 45%) as a colourless solid (mp 48±
1
498C, Lit.26 498C): H NMR (CDCl3): d 0.76 (s, 3H, C-18
CH3), 0.82 (d, Jˆ7.4 Hz, 3H,C-21 CH3), 0.92,(d, 6H, C-26,
27 CH3), 2.18 (s, 3H, C-4 CH3), 7.01, 7.13, and 7.19 (3m,
3H, Ar-H), and 11 (59 mg, 16%) as a colourless solid (mp
70±728C, Lit.27 70±718C):1H NMR (CDCl3): d 0.74 (s, 3H,
C-18 CH3), 0.81 (d, Jˆ6.4 Hz, 3H, CH3), 0.87 (d, Jˆ6.4 Hz,
3H, CH3), 0.95 (s, 3H, C-19 CH3), 1.07 (d, Jˆ6.5 Hz, 3H,
C-21 CH3), 5.54 (dd, Jˆ1.1 and 5.5 Hz, 1H, C-4 H), 5.62
(dd, Jˆ9.5 Hz, 1H, C-6 H), 5.66 (dddd, Jˆ2.6, 6.4, 9.1, and
1.1 Hz, 1H, C-2 H), 5.72 (ddd, Jˆ3.2, 9.1 and 5.5 Hz, 1H,
C-3 H), 5.93 (dd, Jˆ1.9 Hz, 1H, C-7 H). 13C NMR (CDCl3):
d ppm 12.1 15.2 18.9, 21.2, 23.1, 23.3, 24.4, 24.5, 28.4,
28.6, 35.9, 36.2, 36.6, 36.8, 37.3, 39.9, 40.3, 43.5, 51.9,
54.9, 56.8 (21 saturated carbons),119.1 123.9, 125.2,
8. Heath, D. F.; Casapieri, P. Trans. Faraday Soc. 1951, 47,
1093.
9. Le Roux, Y.; Jacques, B.; Grangette, H.; Norfe, C. Bull. Chem.
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11. (a) 1H NMR (CDCl3) d 1.71 and 1.74 (2 s, 2 CH3), 4.75 (broad
s, 2H, CH2), 5.42 and 5.71 (Olef. H). MS (70 eV) (m/z): 134
(M1), 119, 105, 91, 77, 65. (b) The 1H NMR spectrum of the
ketone is identical to the commercially available carvone; 1H
NMR of DNP-derivative (CDCl3): d 1.25 (d, Jˆ7 Hz, 3H,

A. S. Demir / Tetrahedron 57 (2001) 227±233
233
CH3), 1.27±1.42 (m, 1H, CH), 1.51±1.62 (m, 1H, CH), 1.78
(broad s, 3H, CH3), 1.88±2.01 (m, 2H, CH2), 2.02±2.20 (m,
2H, CH2), 2.35±2.45 (m, 1H, CH), 2.87 (m,1H, CH), 4.80 (m,
2H, CH2), 7.98, 8.26, 9.18 (3H, Ar-H), 11.25 (broad s, 1H,
NH). 13C NMR (CDCl3): d 16.7, 20.8, 31.14, 32.50, 35.93,
39.98, 45.89, 96.30, 110.63, 116.32, 123.56, 130.0, 145.66,
147.33, 162.21. MS (70 eV, m/z): 332 (M1), 317, 297, 271,
255, 135, 122, 107, 93, 79, 67, 55.
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