Easy access to N,N-Bis(but-3-enyl)-, N-Allyl-N-(but-3-enyl)-, and N-(but-3-ynyl)-N-(but-3-enyl)-amines

Article abstract of DOI:10.1021/jo020118t

N,N-Bis(but-3-enyl)amines 5a-i were prepared in overall 74% yield from 1-(triphenylphosphoroylideneaminoalkyl)benzotriazole using an aza-Wittig reaction with aldehydes followed by a double Grignard reaction with allylmagnesium bromide. Use of vinyl or 1-propynylmagnesium bromide and allylmagnesium bromide in a sequential fashion also formed the expected doubly unsaturated amines 9a,b and 12, respectively.

Full text of DOI:10.1021/jo020118t

SCHEME 1
Ea sy Access to N,N-Bis(bu t-3-en yl)-,
N-Allyl-N-(bu t-3-en yl)-, a n d
N-(Bu t-3-yn yl)-N-(bu t-3-en yl)-a m in es
Alan R. Katritzky,* Satheesh K. Nair, and Alina Silina
Center for Heterocyclic Compounds, Department of
Chemistry, University of Florida, Gainesville, Florida
32611-7200
katritzky@chem.ufl.edu
Received February 20, 2002
Abstr a ct: N,N-Bis(but-3-enyl)amines 5a -i were prepared
in overall 74% yield from 1-(triphenylphosphoroylideneami-
noalkyl)benzotriazole using an aza-Wittig reaction with
aldehydes followed by a double Grignard reaction with
allylmagnesium bromide. Use of vinyl or 1-propynylmagne-
sium bromide and allylmagnesium bromide in a sequential
fashion also formed the expected doubly unsaturated amines
9a ,b and 12, respectively.
acteristics similar to those of phosphorus ylides and react
with carbonyl compounds to form Schiff bases.11a Imino-
phosphoranes also react with carbon dioxide and carbon
disulfide to yield isocyanates and isothiocyanates, re-
spectively.12 We have reported earlier applications of
1-(t r iph en ylph osph or oyliden ea m in om et h yl)ben zo-
triazole to the synthesis of carbodiimides, imines, isothio-
cyanates, aziridines, secondary and primary amines,13
and N-(vinylimino)phosphoranes.14 Grignard displace-
ments of the benzotriazole group followed by the aza-
Wittig reaction with aldehydes give 83% yields of the
corresponding Schiff bases 2 (Scheme 1).13a
We envisioned that aza-Wittig reactions on 1 should
afford imines 3 with the benzotriazole unit intact.
Intermediates 3 could be synthetic equivalents to amine
R,R′-dications 4. Since nucleophilic addition to imines is
known15 to give amines and since benzotriazole is a good
leaving group,16 a double Grignard addition to 3 with
allylmagnesium bromide should give bis(butenyl)amines
5.
1-(Tr iph en ylph osph or oyliden a m in om et h yl)ben zo-
triazoles 1a -c were prepared following known methods.13
Aza-Wittig coupling of 1a -c with aldehydes 6a -g
occurred in THF at room temperature; when 1a was
stirred with 1 equiv of benzaldehyde in THF for 10 h,
TLC indicated complete reaction. However, attempts to
purify the imine using chromatographic techniques failed,
and vacuum distillation of the imine following the
literature reports13 resulted in charring and significant
loss of material. Fortunately, the crude imine 3a in a
Grignard reaction with 2.2 equiv of allylmagnesium
bromide in THF at 20 °C formed bis(butenyl)amine 5a
in 78% yield. Flash chromatography over silica gel
provided an analytically pure sample of 5a characterized
Ring-closing metathesis (RCM) has emerged as a
powerful tool for the construction of carbocycles and
heterocycles.1 N,N-Bis(3-butenyl)amines, diallylamines,2
and other dialkenylamines3 are versatile candidates for
RCM syntheses of nitrogen-containing heterocycles.4 Bis-
(butenyl)amines can be prepared by the allylation of
sulfinylamines and used in the synthesis of piperidines;5
N-allyl-N-(3-butenyl)amines have been used to prepare
pyrrolidine and piperidine alkaloids.6
Previously, N-butenylamines have been prepared by
multistep sequences.5,6 Substituted bis(butenyl)amines
were obtained from commercially available 4-(2-prope-
nyl)-â-lactams and allyltrimethylsilane7 and used in
RCMs.8 Pearson et al. made N,N-bis(3-butenyl)amines
for tetrahydroazepines ring closures9 from 2-(azaallyl)-
stannanes, obtained in a two-step process starting from
tin bearing phthalides.10 A more general synthetic
route to bisbutenyl and related amines with fewer steps
should facilitate their application. We herein report
such easy access to N,N-(bisbutenyl)amines from readily
available 1-(triphenylphosphoroylideneaminoalkyl)benzo-
triazoles.
Synthetic applications of iminophosphoranes11 are well
documented; they possess structural and chemical char-
(1) (a) Grubbs, R. H.; Chang, S. Tetrahedron 1998, 54, 4413. (b)
Taniguchi, T.; Ogasawara, K. Org. Lett. 2000, 2, 3193. (c) Felpin, F.-
X.; Vo-Thanh, G.; Robins, R. J .; Villieras, J .; Lebreton, J . Synlett 2000,
1646. (d) Varray, S.; Gauzy, C.; Lamaty, F.; Lazaro, R.; Martinez, J .
J . Org. Chem. 2000, 65, 6787.
(2) Paquette, L. A.; Leit, S. M. J . Am. Chem. Soc. 1999, 121, 8126.
(3) Pernerstorfer, J .; Schuster, M.; Blechert, S. Synthesis 1999, 138.
(4) (a) Schuster, M.; Blechert, S. Angew. Chem., Int. Ed. Engl. 1997,
36, 2037. (b) Phillips, A. J .; Abell, A. D. Aldrichimica Acta 1999, 32,
75.
(5) Kumareswaran, R.; Balasubramanian, T.; Hassner, A. Tetrahe-
dron Lett. 2000, 41, 8157.
(11) (a) Staudinger, H.; Meyer, J . Helv. Chim. Acta 1919, 2, 635.
(b) Horner, V. L.; Gross, A. Leibigs Ann. Chem. 1955, 591, 117. (c)
Appel, R.; Hauss, A. Chem. Ber. 1960, 93, 405. (d) Appel, R.; Schollhorn,
R. Angew. Chem. 1964, 76, 991.
(12) Staudinger, H.; Hauser, E. Helv. Chim. Acta. 1921, 4, 861.
(13) (a) Katritzky, A. R.; J iang, J .; Urogdi, L. Synthesis 1990, 565.
(b) Katritzky, A. R.; J iang, J .; Urogdi, L. Tetrahedron Lett. 1989, 30,
3303.
(6) Felpin, F.-X.; Girard, S.; Vo-Thanh, G.; Robins, R. J .; Villieras,
J .; Lebreton, J . J . Org. Chem. 2001, 66, 6305.
(7) Barrett, A. G. M.; Ahmed, M.; Baker, S. P.; Baugh, S. P. D.;
Braddock, D. C.; Procopiou, P. A.; White, A. J . P.; Williams, D. J . J .
Org. Chem. 2000, 65, 3716.
(8) Schurer, S. C.; Gessler, S.; Buschmann, N.; Blechert, S. Angew.
Chem., Int. Ed. 2000, 39, 3898. (b) Vo-Thanh, G.; Boucard, V.; Sauriat-
Dorizon, H.; Guibe, F. Synlett 2001, 37.
(14) Katritzky, A. R.; Mazurkiewicz, R.; Stevens, C. V.; Gordeev, M.
F. J . Org. Chem. 1994, 59, 2740.
(15) Volkmann, R. A. In Comprehensive Organic Synthesis; Trost,
B. M., Fleming, I., Schreiber, S. L., Eds.; Pergamon Press: Oxford,
1991; Vol. 1, pp 355-396.
(16) Katritzky, A. R. J . Heterocycl. Chem. 1999, 36, 1501. (b)
Katritzky, A. R.; Lan, X.; Yang, J . Z.; Denisko, O. V. Chem. Rev. 1998,
98, 409.
(9) Pearson, W. H.; Aponick, A. Org. Lett. 2001, 3, 1327.
(10) Pearson, W. H.; Clark, R. B. Tetrahedron Lett. 1999, 4467.
10.1021/jo020118t CCC: $22.00 © 2002 American Chemical Society
Published on Web 09/21/2002
7530
J . Org. Chem. 2002, 67, 7530-7532

her.17 Our general route to the preparation of these
intermediates provides an easy access to these com-
pounds with their potential applications in RCM.
Advantageously, all three steps of Schemes 3 and 4 can
be carried out sequentially in one-pot reactions to provide
good yields of the amines. Thus 1-(triphenylphospho-
roylideneaminoalkyl)benzotriazoles serve as common
precursors for the preparation of bis(butenyl)-, allylbute-
nyl-, and N-butynyl-3-butenyl-amines depending on the
organometallic reagents used.
In conclusion, convenient synthetic methods are de-
scribed for the preparation of amines of types 5, 9, and
12, which should expedite the synthesis of these inter-
mediates and their applications particularly in the
construction of heterocycles.
TABLE 1. N,N-Bis(3-bu ten yl)a m in es 5 P r ep a r ed
R
R1
yield (%)a
5a
5b
5c
5d
5e
5f
5g
5h
5i
H
CH3
H
CH3
H
butyl
H
H
H
Ph
Ph
78
62 (1:2.3)b
2-thienyl
p-CH3C6H4
cyclohexyl
Ph
71
58 (1:3.5)b
82
67 (1:1)b
Et
82
82
80
p-BrC6H4
2-naphthyl
a
All yields refer to pure isolated product. b Diastereomeric ratio.
SCHEME 2
Exp er im en ta l Section
Melting points were determined using a hot-stage microscope
and are uncorrected. 1H (300 MHz) and 13C (75 MHz) NMR
spectra were recorded on a 300 MHz NMR spectrometer in
chloroform-d solution. Column chromatography was performed
on silica gel. All Grignard reagents were procured as solution
in THF. THF was distilled from sodium-benzophenone ketal
prior to use. All reactions were performed under a nitrogen
atmosphere and in flame dried glasswares. 1-(Triphenylphos-
phoroylideneaminoalkyl)benzotriazoles 1 were prepared follow-
ing the literature method.13
Gen er a l P r oced u r e for th e P r ep a r a tion of Bis(bu ten yl)-
a m in es 5a -i. 1-(Triphenylphosphoroylideneaminoalkyl)benzo-
triazole 1 (10 mmol) was taken up in dry THF (50 mL) and was
allowed to react with the corresponding aldehyde (10 mmol) at
room temperature for 5 h. After TLC analysis indicated complete
consumption of the aldehyde, allylmagnesium bromide (20 mmol,
1 M solution in THF) was added dropwise at room temperature.
After the addition, the reaction mixture was stirred for 2 h at
room temperature, poured into cold water, and extracted with
ether (3 × 100 mL). The combined etherial layer was washed
with 2 N NaOH (2 × 50 mL) followed by water (2 × 50 mL).
The amine 5 was purified by acid-base workup. Further
purification was done by flash column chromatography over
silica gel using hexane as the eluent.
by NMR spectra. 1-(Triphenylphosphoroylidenomethyl)-
benzotriazoles 1b and 1c similarly yielded respectively
amines 5b and 5f, which were isolated as mixtures of
diastereomers as indicated by 1H NMR. The method was
extended to other aldehydes as summarized in Table 1.
Attempts to use ketones in the aza-Wittig reaction failed
even in refluxing toluene. Sequential addition of two
different Grignard reagents to the intermediate imine 3
would make the approach more versatile. However, our
results showed that there is not much selectivity between
the imine carbon and the carbon bearing the benzotria-
zole, and initial attempts resulted in a mixture of
products that were difficult to separate and characterize
(e.g., when 1a was treated with benzaldehyde followed
by sequential addition of single equivalents of vinyl- and
allylmagnesium bromide, TLC indicated an intractable
mixture). Adding the first Grignard reagent to displace
the benzotriazole before the aza-Wittig reaction solved
this problem. Subsequent coupling with an aldehyde and
addition of the second Grignard reagent (allylmagnesium
bromide) succeeded.
Benzotriazole derivative 1a was treated in THF with
1 equiv of vinylmagnesium bromide. The resulting in-
termediate 7a was subjected to aza-Wittig with benzal-
dehyde. Imine 8a was then reacted with 1 equiv of
allylmagnesium bromide. The unsymmetrical bisalkeny-
lamine 9a was isolated in 87% yield after workup and
purification (Scheme 3).
We used propynylmagnesium bromide in the sequen-
tial addition in an extension of this approach to the pre-
parationof N-(2-butynyl)-1-phenyl-3-buten-1-amine 12 in
71% yield (Scheme 4). The only example of an amine of
type 12 reported in the literature is 4-[(1-allyl-1-methoxy-
3-butenyl)amino]-2-butyn-1-ol, which is prepared in three
steps starting from the corresponding bisallyl aminoet-
N-(Bu t-3-en yl)-1-p h en yl-3-bu ten -1-a m in e (5a ): Obtained
1
as a pale yellow oil (78%). H NMR δ 1.42 (bs, 1 H), 2.08-2.15
(m, 2 H), 2.28-2.36 (m, 2 H), 2.39-2.44 (m, 2 H), 3.56 (t, J )
6.6, 1 H), 4.90-5.02 (m, 4 H), 5.55-5.71 (m, 2 H), 7.12-7.23
(m, 5 H). 13C NMR δ 34.1, 42.9, 46.4, 62.4, 116.1, 117.4, 126.8,
127.1, 128.2, 135.4, 136.43, 143.9. Anal. Calcd for C14H19N: C,
83.53; H, 9.51; N, 6.96. Found: C, 83.51; H, 9.60; N, 7.45.
N-(1-Meth yl-3-bu ten yl)-N-(1-ph en yl-3-bu ten yl)am in e (5b).
Obtained (mixture of diastereomers, 2.3:1) as a pale yellow oil
1
(62%). H NMR δ 0.84 (d, J ) 6.6 Hz, 2.1 H), 0.92 (d, J ) 6 Hz,
0.88 H), 1.51 (bs, 1 H), 1.99-2.12 (m, 2 H), 2.26-2.34 (2 H),
2.35-2.55 (m, 1 H), 3.68-3.73 (m, 1 H), 4.92-5.02 (m, 4 H),
5.55-5.62 (m, 2 H), 7.19-7.31 (m, 5 H). 13C NMR δ 19.6, 21.3,
40, 42.4, 43.2, 43.3, 48.8, 49.8, 59.3, 59.8, 116.8, 117.1, 117.4,
126.7, 127, 128.2, 135.3, 135.5, 135.9, 144.0, 144.6. HRMS (FAB)
calcd for C15H22N (M + H) 216.1757, found 216.1757.
N-(Bu t -3-en yl)-1-(2-t h ien yl)-3-b u t en -1-a m in e (5c). Ob-
tained as a pale yellow oil (71%). 1H NMR δ 1.62 (bs, 1 H), 2.18-
2.25 (m, 2 H), 2.45-2.52 (m, 2 H), 2.54-2.68 (m, 2 H), 3.96 (t, J
) 6.9 Hz, 1 H), 4.99-5.14 (m, 4 H), 5.67-5.81 (m, 2 H), 6.89-
6.94 (m, 2 H), 7.18-7.20 (m, 1 H). 13C NMR δ 34.0, 43.4, 46.3,
57.9, 116.3, 117.8, 123.7, 123.8, 126.3, 134.7, 136.3, 149.0. Anal.
Calcd for C12H17N: C, 69.51; H, 8.26; N, 6.76. Found: C, 69.52;
H, 8.79; N, 6.73.
N-(1-Meth yl-3-bu ten yl)-N-(1-(4-m eth ylp h en yl)-3-bu ten y-
l)a m in e (5d ). Obtained (mixture of diastereomers, 3.5:1) as a
pale yellow oil (58%). 1H NMR δ 0.83 (d, J ) 6.6 Hz, 2.4 H),
(17) Courtois, G.; Miginiac, L. J . Organometal. Chem. 1988, 340,
127.
J . Org. Chem, Vol. 67, No. 21, 2002 7531

SCHEME 3
SCHEME 4
0.85 (d, J ) 6.0 Hz, 0.62H), 1.39 (bs, 1 H), 1.96-2.19 (m, 2.6 H),
2.25-2.3 (m, 5.4 H), 2.32-2.56 (m, 1 H), 3.67 (t, J ) 6.6 Hz, 1
H), 4.90-5.02 (m, 4 H), 5.53-5.73 (m, 2 H), 7.04 (d, J ) 6.0 Hz,
2 H), 7.08 (d, J ) 6.0 Hz, 2 H). 13C NMR δ 19.6, 21.0, 21.3, 39.9,
42.4, 43.2, 43.3, 48.7, 49.7, 59.0, 59.4, 116.8, 117.0, 117.1, 117.3,
126.9, 128.9, 135.3, 135.6, 136.0, 136.2, 140.8, 141.5. Anal. Calcd
for C16H23N: C, 83.78; H, 10.11; N, 6.11. Found: C, 81.01; H,
9.16; N, 5.91.
N-(Bu t-3-en yl)-1-cycloh exyl-3-bu ten -1-a m in e (5e). Ob-
tained as a pale yellow oil (82%). 1H NMR δ 0.87-1.21 (m, 6 H),
1.31-1.39 (m, 1 H), 1.61-1.69 (m, 5 H), 1.93-2.03 (m, 1 H),
2.10-2.28 (m, 4), 2.56 (t, J ) 6.9 Hz, 1 H), 4.93-5.03 (m, 4 H),
5.64-5.77 (m, 2 H).13C NMR 26.5, 26.6, 26.7, 28.7, 29.4, 34.5,
35.4, 40.6, 46.9, 62.0, 116.0, 116.6, 136.7. Anal. Calcd for
Gen er a l P r oced u r e for th e P r ep a r a tion of 9a ,b a n d 12.
1-(Triphenylphosphoroylideneaminoalkyl)benzotriazole (10
1
mmol) was taken up in dry THF (50 mL), and the corresponding
vinylic or propargyl Grignard reagent (10.2 mmol) was added
dropwise at room temperature. The mixture was allowed to stir
at room temperature for 3 h, diluted with ether (200 mL), and
filtered. The filtrate was dried over sodium sulfate and concen-
trated, and the oily residue was redissolved in THF (50 mL).
The resulting solution was treated with the appropriate aldehyde
(10 mmol) at room temperature for 5 h. After TLC analysis
indicated complete consumption of the aldehyde, allylmagnesium
bromide (10 mmol, 1 M solution in THF) was added dropwise
at room temperature. After the addition, the reaction mixture
was stirred for 2 h at room temperature, poured into cold water,
and extracted with ether (3 × 100 mL). The combined etherial
layer was washed with 2 N NaOH (2 × 50 mL) followed by water
(2 × 50 mL). The amine was purified by acid-base workup.
Further purification was done by flash column chromatography
over silica gel using hexane as the eluent.
C
14H25N: C, 81.09; H, 12.15; N, 6.75. Found: C, 80.84; H, 12.17;
N, 6.98.
N-(1-P h en yl-3-bu ten yl)-N-(1′-pr opyl-3-bu ten yl)am in e (5f).
Obtained (mixture of diastereomers, 1:1) as a pale yellow oil
1
(67%). H NMR δ 0.76 (t, J ) 6.6 Hz, 1.42 H), 0.871 (t, J ) 6.9
Hz, 1.43 H), 0.94-0.99 (m, 0.36 H), 1.12-1.52 (m, 5 H), 1.55-
2.25 (m, 2 H), 2.27-2.40 (m, 3 H), 3.69-3.81 (m, 1 H), 4.96-
5.08 (m, 4 H), 5.58-5.78 (m, 2 H), 7.19-7.31 (m, 5H). 13C NMR
14.0, 14.4, 18.4, 19.0, 35.6, 37.2, 37.3, 39.3, 41.5, 43.143.5, 53.2,
53.5, 59.4, 59.6, 59.8, 116.7, 117.1, 117.3, 126.7, 126.8, 127.1,
127.2, 128.0, 128.1, 135.1, 135.2, 135.6, 135.7, 136.2, 144.5, 144.6.
Anal. Calcd for C17H25N: C, 83.89; H, 10.35; N, 5.75. Found: C,
83.73; H, 10.80; N, 5.82.
N-Allyl-1-p h en yl-3-bu ten -1-a m in e (9a ). Obtained as
a
colorless liquid (87%). 1H NMR δ 1.49 (bs, 1 H), 2.37-2.42 (m,
2 H), 3.05 (dddd, J ) 20.7, 19.5, 6.6, 5.4 Hz, 2 H), 3.66-3.70 (t,
J ) 7.2 Hz, 1 H), 5.63-5.74 (m, 1 H), 5.77-5.90 (m, 1 H), 7.16-
7.40 (m, 5 H). 13C NMR δ 42.80, 49.8, 61.5, 115.4, 117.3, 126.8,
127.0, 128.1, 135.2, 136.7, 143.5. Anal. Calcd for C13H17N: C,
83.37; H, 9.15; N, 7.48. Found: C, 83.36; H, 9.77; N, 7.68.
N-(2-Met h yl-2-p r op en yl)-1-(4-b r om op h en yl)-3-b u t en -1-
a m in e (9b). Obtained as a pale yellow oil (84%). 1H NMR δ 1.58
(bs, 1 H), 1.74-1.75 (m, 3 H), 2.29-2.39 (m, 2 H), 2.89-3.00
(m, 2 H), 3.61 (t, J ) 7.8 Hz, 1 H), 4.84-4.88 (m, 2 H), 5.09-
5.18 (m, 2 H), 5.63-5.77 (m, 1 H), 7.20 (d, J ) 8.4 Hz, 2 H), 7.42
(d, J ) 8.4 Hz, 2 H). 13C NMR δ 20.7, 43.0, 53.0, 60.6, 110.7,
117.8, 120.5, 128.9, 131.3, 135.0, 143.0, 143.7. Anal. Calcd for
14H18BrN: C, 60.01; H, 6.47; N, 5.00. Found: C, 60.31; H, 6.79;
N, 5.24.
N-(Bu t-2-yn yl)-N-(1-p h en yl-3-bu ten e-1-a m in e (12). Ob-
N-(Bu t-3-en yl)-1-eth yl-3-bu ten -1-a m in e (5g). Obtained as
a pale yellow oil (82%). 1H NMR δ 0.89 (t, J ) 7.5 Hz, 3 H),
1.35-1.48 (m, 2 H), 2.08-2.27 (m, 4 H), 2.44-2.50 (m, 1 H),
2.61-2.69 (m, 2 H), 5.01-5.11 (m, 4 H), 5.70-5.82 (m, 2 H). 13
C
NMR δ 9.9, 26.3, 34.4, 37.9, 46.0, 58.2, 116.2, 117.0, 135.8, 136.5.
Anal. Calcd for C11H23N: C, 78.03; H, 13.69; N, 8.27. Found: C,
78.26; H, 11.96; N, 8.27.
C
N-(Bu t-3-en yl)-1-(4-br om op h en yl)-3-bu ten -1-a m in e (5h ).
Obtained as a pale yellow oil (82%). 1H NMR δ 1.53 (bs, 1 H),
2.15-2.22 (m, 2 H), 21.32-2.34 (m, 2 H), 2.36-2.49 (m, 2 H),
3.61 (t, J ) 6.9 Hz, 1 H), 4.99-5.09 (m, 4 H), 5.61-5.79 (m, 2
H), 7.19 (d, J ) 8.4 Hz, 2 H), 7.44 (d, J ) 8.4 Hz, 2 H). 13C NMR
δ 34.1, 42.9, 46.5, 61.9, 116.3, 117.8, 120.5, 128.9, 131.3, 134.9,
136.3, 143.0. Anal. Calcd For C14H18BrN: C, 60.01; H, 6.47; N,
5.00. Found: C, 60.27; H, 6.63; N, 5.27.
N-(Bu t-3-en yl)-1-(2-n a p h th yl)-3-bu ten -1-a m in e (5i). Ob-
tained as a reddish oil (80%). 1H NMR δ 1.63 (bs, 1 H), 2.09-
2.16 (m, 2 H), 2.36-2.46 (m, 4 H), 3.72 (t, J ) 6.9 Hz, 1 H),
4.90-5.04 (m, 4 H), 5.57-5.71 (m, 2 H), 7.32-7.40 (m, 3 H),
7.65-7.74 (m, 4 H). 13C NMR 34.2, 42.9, 62.6, 116.3, 117.6, 125.2,
125.4, 125.8, 125.9, 127.6, 127.7, 128.1, 182.8, 133.3, 135.3, 136.4,
141.3. Anal. Calcd for C18H21N: C, 86.01; H, 8.42; N, 5.57.
Found: C, 86.29; H, 8.71; N, 5.58.
tained as a pale yellow oil (71%). 1H NMR 1.63 (bs, 1 H), 1.80
(t, J ) 4.5, Hz, 3 H), 2.35-2.49 (m, 2 H), 3.04 (dd, J ) 16.5, 2.1
Hz, 1 H), 3.27 (dd, J ) 14.1, 2.4 Hz, 1 H), 3.84 (dd, J ) 7.8, 6.0
Hz, 1 H), 5.01-5.13 (m, 2 H), 5.65-5.79 (m, 1 H), 7.2-7.32 (m,
5 H). 13C NMR δ 3.4, 36.2, 42.6, 60.6, 78.7, 117.6, 127.0, 127.3,
128.2, 128.3, 135.2, 142.8. HRMS (FAB) calcd for C14H18N (M +
H) 200.1458, found 200.1458.
Su p p or tin g In for m a tion Ava ila ble: Copies of NMR
spectra for 5d and 8a . This material is available free of charge
via the Internet at http://pubs.acs.org.
J O020118T
7532 J . Org. Chem., Vol. 67, No. 21, 2002