Electron transfer induced ring opening of 2-(bromomethyl)aziridines by magnesium in methanol

Article abstract of DOI:10.1016/S0040-4020(02)00728-7

Magnesium metal in methanol was used as a simple electron transfer induced ring-opening reagent of 2-(bromomethyl)aziridines to afford allylamines derivatives in 70-90% yield.

Full text of DOI:10.1016/S0040-4020(02)00728-7

Tetrahedron 58 (2002) 7145–7152
Electron transfer induced ring opening
of 2-(bromomethyl)aziridines by magnesium in methanol
Kourosch Abbaspour Tehrani,† Tuyen NguyenVan, Michinori Karikomi, Mario Rottiers
*
and Norbert De Kimpe
Department of Organic Chemistry, Faculty of Agricultural and Applied Biological Sciences, Ghent University,
Coupure Links 653, B-9000 Ghent, Belgium
Received 14 May 2001; accepted 20 October 2001
Abstract—Magnesium metal in methanol was used as a simple electron transfer induced ring-opening reagent of 2-(bromomethyl)aziridines
to afford allylamines derivatives in 70–90% yield. q 2002 Elsevier Science Ltd. All rights reserved.
1. Introduction
first procedure used a zinc–copper couple8 under sono-
chemical conditions, and the second procedure used
tributyltinhydride and AIBN for the radical initiation.9
Both methods constitute a synthetic method for N-allyl-
amines. However, the former method uses an ultrasonic
generator and the latter method utilized substantial amounts
of toxic tin reagent, in addition requiring elaborate
purification of the final reaction products.
Three-membered heterocycles, including epoxides, oxaziri-
dines and aziridines are prone to ring opening because of the
high ring strain present in these small molecules. As a
consequence, ring-opening reactions of small rings by
radical rearrangement have received much attention
recently (Scheme 1).1 Ring opening of cyclopropanes 1
(Z¼CR1R2) and oxiranes (Z¼O) via cyclopropylmethyl
radicals 2 and 2-oxiranylmethyl radicals 2 (Z¼O), respec-
tively, have been regularly reported in the literature.1 Such
radical-induced ring cleavages have been utilized in a
variety of useful synthetic transformations.2–5 For example,
this ring opening constitutes a useful strategy for the
synthesis of allylic compounds. Analogously, also the
rearrangement of 2-aziridinylmethyl radicals 2 (Z¼NR3)
holds some synthetic potential in organic synthesis.
However, very few such reactions have been reported so
far.6,7
The synthetic utility of magnesium in methanol as electron
transfer agent is being used more and more.10–12 The major
advantage of the Mg–MeOH method is the low cost and
easy handling, contrary to other methods. For example, the
reduction of alkyl halides to alkanes was executed with
magnesium in methanol.13 Another example is the reductive
cleavage of 2-(halomethyl)oxiranes with magnesium in
methanol, which provided a facile method for the synthesis
of allylic alcohols.14
In this article, the use of magnesium in methanol as a
simple electron transfer reagent for the ring opening of
2-(bromomethyl)aziridines towards allylamine derivatives
is reported.
Recently, we have shown that 2-(halomethyl)aziridines are
easily accessible starting materials for the generation of
2-aziridinylmethyl radicals by two alternative methods. The
Scheme 1.
Keywords: aziridines.
*
Corresponding author. Tel.: þ32-9-264-59-51; fax: þ32-9-264-62-43; e-mail: norbert.dekimpe@rug.ac.be
†
Post-doctoral Fellow of the F.W.O.-Flanders (Belgium).
0040–4020/02/$ - see front matter q 2002 Elsevier Science Ltd. All rights reserved.
PII: S0040-4020(02)00728-7

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2. Results and discussion
N-Methanesulfonyl- and N-p-toluenesulfonyl-2-(bromo-
methyl)aziridines 8f,g were synthesized via an alternative
method (Scheme 2).16 N-allyl-p-toluenesulfonamide 9a
and N-allylmethanesulfonamide 9b were brominated by
bromine in dichloromethane at 08C to give N-tosyl and
N-mesyl-2,3-dibromopropylamines 10a,b, which were
subsequently treated with aqueous sodium hydroxide
(1 M) in ethanol at room temperature to afford the
corresponding N-tosyl- and N-mesyl-2-(bromomethyl)aziri-
dines 8f,g in 83–90% yield (Scheme 2). 2-Bromomethyl-N-
( p-toluenesulfonyl)aziridine 8e has been prepared very
recently by another group by aziridination of allylbromide
with chloramine-T and pyridinium hydrobromide per-
bromide.17 Surprisingly, the spectral data (1H NMR,
13C NMR, MS, IR) reported in this reference were
2-(Bromomethyl)aziridines 8a–d are accessible from
aldehydes 5a–d by a three-step synthetic sequence (Scheme
2). Condensation of aldehydes 5a–d with allylamine in
dichloromethane in the presence of magnesium sulfate
afforded the corresponding N-allylimines 6a–d (Scheme 2),
which were subsequently brominated by bromine in
dichloromethane to give N-(arylidene)-2,3-dibromopropyl-
amines 7a–d. The latter dibromoimines 7a–d were
not further purified because of their instability and
hence reacted with sodium borohydride in methanol
under reflux to produce 2-(bromomethyl)aziridines 8a–d
in 86–90% yield.15 In the case of the synthesis of 8e,
3-cyclohexene-1-carboxaldehyde 11 was condensed
with 2,3-dibromo-1-propylammonium bromide in the
presence of 1 equiv. triethylamine and magnesium sulfate
as drying agent. Reduction of 7e by means of sodium
borohydride in methanol afforded a 1/1 mixture of
diastereoisomeric aziridines 8e, which could not be
separated by column chromatography or by preparative
gas chromatography. Because of the unrelevance for the
next reaction, no further efforts were undertaken to separate
these isomers.
1
different from our data and even not correct. In the H
NMR spectrum, the typical coupling between
NC(H)Htrans, NC(Hcis)H and the NCH was not visible.
Moreover, integrations in the region 3.50–5.25 ppm were
not correct and in a very bad ratio with the aromatic
signals. In addition, in the literature, a melting point
was reported at 76–778C, while our product never solidi-
fied, even not after distillation (boiling point 1468C/
0.1 mmHg).
Scheme 2.

K. Abbaspour Tehrani et al. / Tetrahedron 58 (2002) 7145–7152
7147
Scheme 3.
Ring opening of 2-(bromomethyl)aziridines 8a–e in dry
methanol at room temperature in the presence of 5 equiv. of
magnesium metal was first executed at room temperature
during 3 days. In the case of aziridines 8f,g with a strong
electron-withdrawing group the corresponding ring-opening
product was isolated in excellent yield, after non-aqueous
workup by filtration over silica gel. The same workup
procedure, performed on the aziridines 8a–e, however,
furnished the corresponding hydrobromide salts 17a–e.
This reductive cleavage of N-benzyl- and N-p-chloro-
benzylaziridine 8a,d with magnesium in methanol has
been recently reported by Pak et al.12 By using the same
workup procedure these authors identified the reaction
products as N-allyl-N-benzylamine 17a and N-allyl-(4-
chlorobenzyl)amine 17d, respectively. Since the reported
spectrometric data were identical with our own results, it
was concluded that also in this reference the hydrobromide
salts had been isolated and as such mistakenly assigned to
the free amines. To prove unequivocally that the hydro-
bromide salts were isolated, the free amines were treated
with hydrogen bromide gas in diethyl ether at room
temperature. The question remaining is why hydrobromide
salts persist in a basic medium such as magnesium
methoxide in methanol. The conversion of 2-(bromo-
methyl)aziridines 8a–g can be interpreted as occurring
via single electron transfer from magnesium metal to the
substrate, followed by loss of bromide from the radical
anion 12 to form the radical 13. The latter radical 13 could
rearrange to the aminyl radical 14, which further gives the
final allylamine derivatives 17a–e.HBr (Scheme 3). A
second electron transfer to the carbon-centered radical 13
might intervene, resulting in a carbanionic species 16, which
undergoes ring opening to give the corresponding N-allyl-
amide anion 15. Protonation of the latter amide by the
solvent affords allylamines 17. From this hypothesis it was
thought that after reaction the mixture contains 1 equiv. of a
free allylamine 17, 4.5 equiv. of magnesium methoxide and
0.5 equiv. of magnesium dibromide. To explain the origin of
the hydrogen bromide a mixture, consisting of 4.5 equiv. of
magnesium methoxide, 1 equiv. of N-allyl-N-benzylamine
and 0.5 equiv. of commercial anhydrous magnesium
bromide in dry methanol, was filtered over a silica gel
column and eluted with methanol. In this case the
hydrobromide salt of N-allyl-N-benzylamine 17a was
isolated after evaporation of methanol in vacuo. An
analogous mixture without magnesium methoxide,
furnished the free amine after filtration over silica gel.
Alternatively it is possible and probably more likely that
instead of 0.5 equiv. magnesium dibromide, 1 equiv. of
methoxymagnesium bromide is formed. An indication for
the presence of the latter species is found by mixing clear
solutions of magnesium dibromide and magnesium
methoxide in dry methanol (exothermic reaction!). A grey
colloidal suspension was formed, very similar to the
reaction mixture obtained by reaction of 2-(bromomethyl)-
aziridines 8a–g with magnesium. The addition of 1 equiv.
of N-allyl-N-benzylamine 17a to the latter mixture, and
filtration over silica gel also afforded N-allyl-N-benzyl-
ammonium bromide 17a.HBr. It is known that the
magnesium ion has a strong affinity for oxygen; therefore
methoxymagnesium bromide will bind to the silica gel,
releasing 1 equiv. of methanol. The presence of a strong
base-like methoxide or hydroxide is required to deprotonate
the weakly acidic silanol groups (pKa¼5.5–7.5) and thus

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660/H ultrason bath (35 kHz). Dichloromethane was dried
over calcium hydride. Methanol was dried by distillation
over magnesium and diethyl ether by distillation over
sodium benzophenone ketyl. Other solvents were used as
received from the supplier. Silica gel had a pore diameter of
ca. 6 nm, and 0.035–0.070 mm size. The synthesis and
spectral data of 1-benzyl-2-(bromomethyl)aziridine 8a
and 2-(bromomethyl)-1-(4-chlorobenzyl)aziridine 8d is
reported elsewhere.15 Compounds 9a and 9b were prepared
in quantitative yield through reaction of allylamine with
p-toluenesulfonyl chloride and methanesulfonyl chloride,
respectively.20 2,3-Dibromo-1-propylammonium bromide
was prepared by a literature method.21
3.1. N-Arylidene-2-propenylamines 6a–c15
Scheme 4.
enhance the affinity of oxygen for magnesium.18 Next,
bromide will be expelled by another silanol group, thus
giving rise to hydrogen bromide, which will be trapped by
the free allylamines 17a–e (Scheme 4).
A mixture of 0.1 mol of the appropriate aromatic aldehyde
5a–c in 100 mL of dichloromethane was treated with
0.11 mol of allylamine and 13 g of magnesium sulfate. The
mixture was stirred at room temperature for 1 h, and then
filtered. The filter cake was washed with dichloromethane.
The combined filtrates were evaporated, after which the
N-allylaldimines 6 were distilled in vacuo. Despite the fact
that these compounds are known, spectrometric data have
never been published, therefore they are reported here.
It is worth mentioning that in the case of the reaction of
N-tosylated aziridine 8f with magnesium in methanol only
ring-opened product was isolated, and no trace of
N-detosylated compounds have been found. In the literature,
a similar reaction between 2-phenyl-N-tosylaziridine and
magnesium gave rise to the ring-opened products and
2-phenylaziridine.19 Sonication of 2-(bromomethyl)aziri-
dines 8a,d in methanol in the presence of 5 equiv. of
magnesium turnings during 4 h at room temperature
resulted in clean ring opening of the aziridine, leading to
allylamines 17a,d after filtration of the reaction mixture
over silica gel. Because of the fact that in these cases the
reaction time could be drastically reduced (from 3 days to
4 h) also the less reactive 1-( p-chlorobenzyl)-2-(chloro-
methyl)aziridine was treated with magnesium in methanol
under sonochemical conditions. In this case, however,
3.1.1. N-(Phenylmethylidene)-N-(2-propenyl)amine 6a.
Yield 94%; bp 588C/0.05 mmHg. 1H NMR (270 MHz,
CDCl3): d 4.19–4.20 (2H, m, NCH2); 5.08–5.20 (2H, m,
CHvCH2); 5.97–6.13 (1H, m, CHvCH2); 7.30–7.40 (3H,
m, HCmeta and HCpara); 7.67–7.79 (2H, m, HCortho); 8.18
(1H, s, CHvN). 13C NMR (68 MHz, CDCl3): d 63.41
(NC H2CH); 115.88 (CHvC H2); 128.08 and 128.5 (HCortho
and HCmeta or vice versa); 130.58 (HCpara); 135.90
(C HvCH2); 136.19 (C–CHvN); 167.72 (CvN). IR
(NaCl, cm21): n¼1643 (CvN). MS (70 eV) m/z (%): 145
(Mþ; 61); 144 (100); 130 (4); 118 (13); 117 (39); 115 (5);
104 (38); 92 (6); 91 (31); 90 (32); 89 (16); 78 (6); 77 (19); 68
(10); 65 (7); 63 (8); 58 (7); 54 (10); 51 (18); 50 (6).
1
even after 4 h sonication only traces (,5%, H NMR) of
ring-opened product was observed.
In conclusion, magnesium in methanol showed to be a
suitable and simple electron transfer reagent in the ring
opening of 2-(bromomethyl)aziridines to obtain allylamine
derivatives in 70–90% yield. It was possible to isolate the
reaction products as free amines or as their hydrobromide
salts, depending on the workup procedure. Erroneous data
from the literature have been corrected.
3.1.2. N-((4-Methoxyphenyl)methylidene)-N-(2-pro-
penyl)amine 6b. Yield 93%; bp 788C/0.05 mmHg. 1H
NMR (270 MHz, CDCl3): d 3.83 (3H, s, OCH3); 4.22 (2H,
d, J¼5.6 Hz, NCH2); 5.11–5.25 (2H, m, CHvCH2); 5.98–
6.10 (1H, m, CHvCH2); 6.89 and 7.68 (each 2H, each d,
J¼8.9 Hz, HCortho and HCpara); 8.21 (1H, s, CHvN). 13C
NMR (68 MHz, CDCl3): d 55.24 (OCH3); 63.40 (CH2N);
113.92 (2£HCmeta); 115.79 (vCH2); 129.14 (C–CHvN);
129.65 (2£HCortho); 136.21 (C HvCH2); 161.20 (CHvN);
161.63 (C–OCH3). IR (NaCl, cm21): n¼1689 (CvN);
1648; 1606; 1578; 1512. MS (70 eV) m/z (%): 175 (Mþ;
36); 174 (Mþ21, 74); 171 (14); 160 (10); 157 (72); 149
(12); 148 (15); 134 (23); 130 (58); 121 (28); 117 (100); 104
(62); 103 (39); 91 (48); 86 (27); 77 (54); 67 (16); 63 (15); 57
(28); 54 (12); 51 (52); 43 (40).
3. Experimental
1H NMR spectra were recorded at 60 MHz (JEOL PMX 60
SI) or 270 MHz (JEOL JNM-EX 270) with CCl4, CDCl3 or
DMSO-d6 as solvent and tetramethylsilane as an internal
standard. 13C NMR spectra were recorded at 20 or 68 MHz
(JEOL JNM-EX 270) with CDCl3, CCl4 or DMSO-d6 as
solvent. Mass spectra were obtained with a mass spectro-
meter (VARIAN MAT 112, 70 eV) using a GC–MS
coupling (RSL 200, 20 m glass capillary column, 0.53 mm
i.d., He carrier gas). IR spectra were measured with a Perkin
Elmer 1310 spectrophotometer or a Spectrum One FT-IR.
Melting points were determined on a Bu¨chi 540 apparatus.
Sonication experiments were performed with a Transsonic
3.1.3. N-((4-Bromophenyl)methylidene)-N-(2-propenyl)-
amine 6c. Yield 90%; bp 918C/1 mmHg. 1H NMR
(270 MHz, CDCl3): d 4.22 (2H, d, J¼5.6 Hz, NCH2);
5.13–5.25 (2H, m, CHvCH2); 5.97–6.12 (1H, m,
CHvCH2); 7.51 and 7.61 (each 2H, each d, J¼8.2 Hz,
HCortho and HCpara); 8.20 (1H, s, CHvN). 13C NMR
(68 MHz, CDCl3): d 63.39 (CH2N); 116.15 (vCH2);

K. Abbaspour Tehrani et al. / Tetrahedron 58 (2002) 7145–7152
7149
125.11 (vC–Br); 129.49 and 131.73 (HCortho and HCmeta
or vice versa); 135.00 (C–CHvN); 135.58 (CHvCH2);
160.46 (CHvN). IR (NaCl, cm21): n¼1649 (CvN); 1589;
1487. MS (70 eV) m/z (%): 224/6 (Mþ; 100); 223 (54); 222
(98); 197 (14); 184 (23); 183 (9); 169 (19); 144 (32); 117
(16); 116 (43); 115 (12); 98 (9); 90 (16); 89 (16); 77 (9); 68
(15); 63 (16); 50 (20); 54 (33); 43 (7).
116 (12); 111 (17); 102 (14); 90 (18); 89 (34); 76 (15); 75
(21); 63 (17); 51 (15); 50 (14); 41 (36).
3.2.3. 2,3-Dibromo-N-(3-cyclohexen-1-yl-methylidene)-
1-propanamine 7e. Crude yield 95%, yellow oil.
Attempted distillation under vacuum (0.5 mmHg, oil bath
1008C) resulted in a very exothermic decomposition of the
crude product. Therefore, the product was used as such in
the next step (purity.96%). 1H NMR (270 MHz, CDCl3): d
1.4–2.6 (8H, m, CH2CHvCHCH2CH2CH ); 3.7–4.0 (4H,
m, CH2N and CH2Br); 4.35–4.48 (1H, m, CHBr); 6.69 (2H,
broad s, CHvCH); 7.67 (1H, d, J¼4.6 Hz, NCHv). 13C
NMR (68 MHz, CDCl3): d 24.08 (CH2); 25.52 (CH); 27.78
(C H2CHv); 33.82 (C H2CHv); 39.35 (CHBr); 51.12
(CH2Br); 64.08 (CH2N); 125.26 (C HvCH); 126.97 and
127.02 (CHvC H); 171.91 and 172.00 (CvN). IR (NaCl,
cm21): n¼1670 (CvN); 1652 (CvC). It was not possible to
obtain a correct mass spectrum of this compound due to its
lability.
3.1.4. N-((4-Chlorophenyl)methylidene)-N-(2-propenyl)-
1
amine 6d. Yield 94%; bp 61–638C/0.05 mmHg. H NMR
(270 MHz, CDCl3): d 4.19 (2H, d, J¼5.48 Hz, NCH2);
5.08–5.25 (2H, m, CHvCH2); 5.94–6.09 (1H, m,
CHvCH2); 7.31 and 7.60 (each 2H, each d, J¼8.44 Hz,
HCortho and HCpara); 8.17 (1H, s, CHvN). 13C NMR
(68 MHz, CDCl3): d 63.07 (CH2N); 115.81 (vCH2);
128.50 and 129.00 (HCortho and HCmeta or vice
versa); 134.41 (C–CHvN); 135.42 (CHvCH2); 136.21
(vC–Cl); 159.96 (CHvN). IR (NaCl, cm21): n¼1646
(CvN). MS (70 eV) m/z (%): 179/81 (Mþ; 52); 178 (100);
152 (27); 151 (27); 144 (15); 138 (24); 124 (15); 117 (9);
111 (9); 95 (13); 89 (26); 75 (12); 63 (9); 54 (14); 51 (17); 49
(42).
3.3. 2-(Bromomethyl)aziridines 8a–c15
A stirred solution of 0.1 mol of N-arylidene-2,3-dibromo-
propylamine 7a–c in 150 mL of absolute methanol was
treated portionwise with 0.2 mol of sodium borohydride.
The reaction was refluxed for 2 h, then cooled to room
temperature. The solution was poured into water, and
extraction was performed with dichloromethane (three
times 100 mL). The combined extracts were dried
(MgSO4) and evaporated in vacuo to give the crude
aziridines, which were purified by flash chromatography
on silica gel (n-hexane/ethyl acetate: 8/2) affording pure
compounds 8a–d. Spectral data of compounds 8a and 8d
have been reported elsewhere.15
3.2. N-Arylidene-2,3-dibromopropylamines 7a–d15
A stirred and cooled (08C) solution of 0.1 mol of
N-(arylidene)allylamines 6 in 150 mL of dry dichloro-
methane was treated dropwise with a solution of 0.1 mol of
bromine in 30 mL of dichloromethane. After complete
addition, stirring was continued at 08C for 30 min and the
solvent was removed in vacuo to afford the N-arylidene-2,
3-dibromopropylamines 7a–d in quantitative yield
(purity.97%). These labile dibromoaldimines 7 were
used as such for the next step.
3.2.1. N-(Benzylidene)-2,3-dibromopropylamine 7a.
1
Crude yield 100%, yellow oil. H NMR (60 MHz, CCl4):
3.3.1. 2-Bromomethyl-1-(4-methoxybenzyl)aziridine 8b.
1
Yield 86%; colorless oil. H NMR (270 MHz, CDCl3): d
d 3.88 (2H, d, J¼6.8 Hz, CH2N); 4.0–4.2 (2H, m, CH2Br);
4.2–4.7 (1H, m, CHBr); 7.3–7.6 (3H, m, vCHpara, meta);
7.6–7.9 (2H, m, vCHortho); 8.33 (1H, broad s, CHvN).
13C NMR (20 MHz, CDCl3): d 34.00 (t, CH2Br); 51.10
(d, CHBr); 64.00 (t, CH2N); 128.30 and 128.50 (each d,
vCmeta and vCpara); 130.96 (d, vCortho); 135.63 (s, Cquat);
163.59 (d, CHvN). IR (NaCl, cm21): n¼1645 (CvN). MS
(70 eV) m/z (%): 303/5/7 (Mþ; 1); 224/6 (24); 169/71 (2);
149 (9); 145 (7); 144 (12); 121 (5); 118 (100); 117 (10); 106
(5); 105 (7); 104 (15); 92 (7); 91 (86); 90 (12); 89 (12); 77
(19); 76 (5); 65 (7); 63 (5); 58 (5); 57 (5); 51 (14); 50 (7); 44
(3); 43 (5); 41 (33).
1.62 (1H, d, J¼6.3 Hz, NC(H)Hcis); 1.78 (1H, d, J¼3.3 Hz,
NC(Htrans)H); 1.91–1.95 (1H, m, NCH); 3.30 (1H, d£d,
J¼6.3, 2.7 Hz, CH2Br); 3.34 and 3.51 (each 1H, each d,
J¼12.9 Hz, C6H4CH2); 3.80 (3H, s, OCH3); 6.87 and 7.25
(each 2H, each d, J¼8.6 Hz, C6H4). 13C NMR (68 MHz,
CDCl3): d 35.11 and 35.26 (CH2N and CH2Br or vice
versa); 39.84 (NCH); 54.97 (OCH3); 63.40 (C6H4C H2);
113.51 and 129.18 (HCorthoþmeta); 130.39 (C–CH2); 158.60
(C–OMe). IR (NaCl, cm21): n¼1613; 1514; 1274; 1026.
MS (70 eV) m/z (%): 255/257 (Mþ, 1); 176 (11); 121 (100);
91 (96); 70 (84); 65 (7). Anal. calcd for C11H14BrNO: C
51.58%; H 5.51%; N 5.47%. Found: C 51.76%; H 5.62%; N
5.33%.
3.2.2. N-(4-Chlorobenzylidene)-2,3-dibromopropyl-
amine 7d. Crude yield 100%, yellow oil. 1H NMR
(60 MHz, CCl4): d 3.93 (2H, d, J¼7.2 Hz, CH2N); 4.1–
4.3 (2H, m, CH2Br); 4.3–4.8 (1H, m, CHBr); 7.52 and 7.84
(each 2H, each d, J¼8.8 Hz, vCHpara, meta); 8.40 (1H,
broad s, CHvN). 13C NMR (20 MHz, CDCl3): d 33.89 (t,
CH2Br); 50.61 (d, CHBr); 63.34 (t, CH2N); 129.06 and
130.09 (each d, vCmeta and vCpara); 130.84 and 137.92 (s,
Cquat); 163.31 (d, CHvN). IR (NaCl, cm21): n¼1648
(CvN). MS (70 eV) m/z (%): 337/39/41/43 (Mþ; 10); 263
(21); 262 (21); 259/61 (12); 258/60 (42); 179 (12); 155 (15);
154 (49); 153 (30); 152 (100); 140 (12); 138 (21); 128 (12);
127 (45); 126 (22); 125 (84); 124 (15); 121 (15); 117/9 (14);
3.3.2. 1-(4-Bromobenzyl)-2-bromomethylaziridine 8c.
1
Yield 90%; colorless oil. H NMR (270 MHz, CDCl3): d
1.79 (1H, d, J¼6.3 Hz, NC(H)Hcis); 1.82 (1H, d, J¼3.3 Hz,
N(Htrans)H); 1.89–1.96 (1H, m, NCH); 3.28 (1H, d£d,
J¼10.1, 6.9 Hz, C(H )HBr); 3.33 (1H, d£d, J¼10.1, 6.1 Hz,
C(H)HBr); 3.36 and 3.50 (each 1H, each d, J¼13.5 Hz,
C6H4CH2); 7.23 and 7.46 (each 2H, each d, J¼8.6 Hz,
C6H4). 13C NMR (68 MHz, CDCl3): d 34.95 and 35.60
(CH2N and CH2Br); 40.20 (NCH); 63.38 (C6H4C H2);
120.94 (vC–CH2); 129.69 and 131.30 (HCorthoþmeta);
137.41 (vC–Br). IR (NaCl, cm21): n¼1592; 1487; 1404;
1222; 1070; 1010; 801. MS (70 eV) m/z (%): no Mþ;

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K. Abbaspour Tehrani et al. / Tetrahedron 58 (2002) 7145–7152
224/226 (Mþ2Br, 6); 212/214 (2); 188/190 (3); 170/172
(13); 84 (13); 51 (28); 49 (100). Anal. calcd for
C10H11Br2N: C 39.38%; H 3.64%; N 4.59%. Found: C
39.49%; H 3.52%; N 4.49%.
2.67 (1H, d, J¼4.0 Hz, NC(H)Htrans); 2.79 (1H, d, J¼
6.9 Hz, NC(Hcis)H); 3.05–3.18 (1H, m, NCH); 3.14 (3H, s,
CH3); 3.20 (1H, d£d, J¼10.5, 8.2 Hz, C(H)HBr); 3.51
(1H, d£d, J¼10.5, 4.6 Hz, C(H )HBr). 13C NMR (68 MHz,
CDCl3): d 21.25 (CH3); 33.49 (CH2N); 39.70 (CH2Br);
40.00 (NCH). IR (NaCl, cm21): n¼3028; 1648; 1428; 1314.
MS (70 eV) m/z (%): 215/213 (Mþ, 1); 134 (87); 55 (100).
Anal. calcd for C4H8BrSO2N: C 22.44%; H 3.77%; N
6.54%. Found: C 22.38%; H 3.86%; N 6.69%.
3.3.3. 2-(Bromomethyl)-1-(3-cyclohexen-1-yl-methyl)-
aziridine 8e. Yield 75%; light yellow oil. An inseparable
mixture of two diastereomers was obtained as observed in
the 13C NMR spectrum. Capillary GC analysis however
showed only one peak, though broadened. Spectra were
recorded on the purified mixture of two diastereomers.
Eluent EtOAc/n-hexane 40/60, Rf¼0.41. 1H NMR
(270 MHz, CDCl3): d 1.2–1.4 and 1.7–1.8 (2£1H, 2£m,
CH2); 1.2–1.4 and 1.9–2.1 (2£1H, 2£m, CH2, other
diastereomer); 1.7–2.2 (2H, m, CH2); 2.0–2.3 (2£1H,
2£m, CH overlap); 1.7–2.0 (1H, m, CH overlap); 1.47–
1.51 and 1.7–1.8 (2£1H, m, CH2); 6.67 (2H, broad s,
CHvCH). 13C NMR (68 MHz, CDCl3): d 24.69 and 24.74
(CH2); 26.75 and 27.04 (CH2); 29.97 and 30.08 (CH); 34.27
(2£CH); 35.76 and 35.83 (CH2Br); 36.08 (2£CH2); 39.98
(2£CH2); 66.76 and 67.12 (CH2N); 125.91; 126.13; 126.83
and 127.19 (CHvCH). IR (NaCl, cm21): n¼1651 (CvC);
3020; 2913; 2835; 1450; 1435; 1220. MS (70 eV) m/z (%):
230/32 (Mþ; 11); 187/9 (4); 151 (70); 149 (11); 110 (3); 96
(7); 95 (11); 94 (18); 81 (6); 80 (18); 71 (100); 69 (7); 68
(13); 56 (5); 55 (6); 53 (6). Anal. calcd for C10H16BrN: C
52.19%; H 7.01; N 6.09%. Found: C 52.02%; H 7.12%; N
6.20%.
3.5. Reaction of 2-(bromomethyl)aziridines with
magnesium in methanol
Method 1. To a stirred solution of 3 mmol of 2-(bromo-
methyl)aziridine 8 in 10 mL of dry methanol was added
0.36 g (15 mmol) of magnesium metal (turnings). The
reaction mixture was stirred at room temperature for 3 days
under nitrogen atmosphere. Afterwards the reaction mixture
was passed through a silica gel column (diameter 2 cm,
20 cm length) and the column was eluted with 50 mL of
methanol. The elutes were concentrated in vacuo to give the
pure ammonium bromide 17a–e.HBr or N-allylamide
17f,g. Compounds 17f,g could be purified by high vacuum
distillation. Basic workup of the hydrobromides 17a–e.HBr
with 2 M aqueous sodium hydroxide solution and extraction
with dichloromethane furnished the free amines 17a–e as
colorless to light yellow oils after drying (MgSO4) and
evaporation of the solvent in vacuo.
3.4. 1-Mesyl- and 1-tosyl-2-(bromomethyl)aziridines
8d,e
Method 2. To a solution of 3 mmol of 2-(bromomethyl)-
aziridine 8 in 10 mL of dry methanol was added 0.36 g
(15 mmol) of magnesium metal (turnings). The reaction
mixture was sonicated for 4 hours under nitrogen atmos-
phere. The reaction was started at room temperature and
gradually the temperature rose to 50–608C after 4 h. The
workup procedure is identical to method 1.
A stirred and cooled (08C) solution of 150 mmol of N-allyl-
p-toluenesulfonamide 9a or N-allylmethanesulfonamide 9b
in 150 mL of dry dichloromethane was treated dropwise
with a solution of 150 mmol of bromine in 50 mL of
dichloromethane. After complete addition, stirring was
continued at 08C for 1 h and the solvent was removed in
vacuo. Then the reaction mixture was dissolved in 100 mL
of ethanol and this solution was added to 1 M aqueous
sodium hydroxide solution (750 mL). The reaction mixture
was stirred for 10 min at room temperature and extracted
with ether. The organic solution was dried (MgSO4) and
concentrated in vacuo to give the crude products.
3.5.1. N-Allyl-N-benzylamine hydrobromide 17a.HBr.
Yield 90%; white crystals; mp 139.5–140.18C. The 1H
NMR and 13C NMR are in agreement between certain limits
with the literature data published for the so-called free
amine 17a (see text).12 1H NMR (270 MHz, CDCl3): d 3.48
(2H, d, J¼6.9 Hz, CH2NH); 4.08 (2H, s, C6H5CH2N);
5.41–5.49 (2H, m, CH2vCH); 6.04–6.19 (1H, m,
CH2vCH); 7.36–7.44 (3H, m, HCmeta and HCpara);
7.59–7.63 (2H, m, HCortho); 9.5 (2H, broad s, þNH2). 13C
NMR (68 MHz, CDCl3): d 48.16 (C H2C6H4); 49.40
(CH2NH); 124.49 (C H2vCH); 127.46; 129.09 (2£
vCHarom); 129.54; 129.77; 130.65 (2£vCHarom). IR
(KBr pellet, cm21): n¼3130–2551; 2399; 1646; 1612;
1572; 1501; 1455; 1424; 1213; 989; 942. Anal. calcd for
C10H14BrN: C 52.65%; H 6.19%; N 6.14%. Found: C
52.55%; H 6.26%; N 6.22%.
3.4.1. 1-(Bromomethyl)-1-( p-toluenesulfonyl)aziridine
8e. Yield 90%; colorless oil; bp 1468C/0.1 mmHg. Flash
chromatography on silica gel: EtOAc/n-hexane: 1/4, Rf¼
0.24. 1H NMR (270 MHz, CDCl3): d 2.21 (1H, d, J¼4.0 Hz,
NC(H)Htrans); 2.43 (3H, s, CH3); 2.82 (1H, d, J¼6.6 Hz,
NC(Hcis)H); 3.05–3.10 (1H, m, NCH); 3.25 (2H, d, J¼
6.3 Hz, CH2Br); 7.36 and 7.82 (2H, d, J¼8.3 Hz, HCmeta
and HCortho). 13C NMR (68 MHz, CDCl3): d 21.61 (CH3);
30.73 (CH2N); 34.20 (CH2Br); 39.83 (NCH); 128.24
(2£HCarom); 129.72 (2£HCarom); 134.30 (Cquat); 144.89
(Cquat). IR (KBr, cm21): n¼1647; 1596; 1425; 1162; 1093.
MS (70 eV) m/z (%): 289/291 (Mþ, 1); 210 (Mþ2Br, 35);
155 (49); 134 (63); 91 (100); 55 (71). Anal. calcd for
C10H12BrSO2N: C 41.39%; H 4.17%; N 4.83%. Found: C
41.25%; H 4.27%; N 4.76%.
3.5.2. N-Allyl-N-benzylamine 17a. Yield 70%; colorless
oil. 1H NMR (270 MHz, CDCl3): d 1.44 (1H, broad s, NH);
3.25 (2H, d£d, J¼5.9, 1.3 Hz, NHCH2); 3.76 (2H, s,
C6H5CH2); 5.07–5.21 (2H, m, CHvCH2); 5.84–5.99 (1H,
m, CHvCH2); 7.19–7.31 (5H, m, C6H5). 13C NMR
(68 MHz, CDCl3): d 51.75 (NHCH2); 53.24 (C6H4CH2);
115.94 (C H2vCH); 126.92 (HCpara); 128.16 and 128.37
(HCorthoþmeta); 136.80 (CH2vC H); 140.27 (Carom, quat). IR
(NaCl, cm21): n¼3314 (NH); 1643; 1604; 1495; 1454
3.4.2. 2-(Bromomethyl)-1-(methanesulfonyl)aziridine 8f.
1
Yield 83%; colorless oil. H NMR (270 MHz, CDCl3): d

K. Abbaspour Tehrani et al. / Tetrahedron 58 (2002) 7145–7152
7151
(CvC). MS (70 eV) m/z (%): 148 (Mþ; 31); 91 (100); 57
(31). These spectra are in accordance with the literature
data.22
(CH2vC H); 139.12 (Cquat); IR (NaCl, cm21): n¼3312
(NH); 1643 (CHvCH2); 1592; 1487; 1403; 1104; 1070;
1011; 994. MS (70 eV) m/z (%): 225/227 (Mþ, 37); 214/212
(15); 172/170 (100); 122 (55); 121 (57). Anal. calcd for
C10H12BrN: C 53.12%; H 5.35%; N 6.19%. Found: C
52.97%; H 5.25%; N 6.31%.
3.5.3. N-Allyl-N-(4-methoxybenzyl)amine hydrobromide
17b.HBr. Yield 90%; white crystals; mp 136.7–137.68C.
1H NMR (270 MHz, CDCl3): d 3.43 (2H, t£d, J¼5.9,
5.1 Hz, vCH2CH2N); 3.72 (3H, s, OCH3); 3.98 (2H, t,
J¼5.4 Hz, CH2NH2); 5.38–5.45 (2H, m, CH2vCH); 5.99–
6.15 (1H, m, CH2vCH ); 6.86 (2H, d, J¼8.6 Hz, 2£
HCHarom); 7.49 (2H, d, J¼8.6 Hz, 2£HCarom); 9.3 (2H,
broad s, þNH2). 13C NMR (CDCl3): d 48.00 and 48.98
(CH2C6H4 and CH2NH); 55.20 (OCH3); 114.37 (2£
HCarom); 121.62 and 124.35 (CH2vCH and C–CH2);
127.56 (CH2vCH); 132.22 (2£HCarom); 160.37
(C–OMe). IR (KBr pellet, cm21): n¼3130–2300; 1614;
1584; 1568; 1516; 1455; 1431; 1299; 1250; 1180; 1036.
Anal. calcd for C11H16BrNO: C 51.18%; H 6.25%; N
5.43%. Found: C 51.30%; H 6.31%; N 5.31%.
3.5.7. N-Allyl-N-(4-chlorobenzyl)amine hydrobromide
17d.HBr. Yield 85%; white crystals; mp 194.8–195.68C.
The 1H NMR and 13C NMR spectral data are in agreement
between certain limits with the literature data published
for the so-called free amine 17d.16 1H NMR (270 MHz,
CDCl3): d 3.46 (2H, d, J¼6.9 Hz, þNH2CH2CHv); 4.04
(2H, s, C6H4CH2); 5.42–5.51 (2H, m, CHvCH2); 6.08 (1H,
d£d£t, J¼17.2, 10.9, 6.9 Hz, CHvCH2); 7.37 and 7.56
(2£2H, 2£d, J¼8.4 Hz, C6H4). 1H NMR (270 MHz,
DMSO): d 3.62 (2H, d, J¼6.3 Hz, þNH2CH2CHv); 4.16
(2H, s, C6H4CH2); 5.40–5.51 (2H, m, CHvCH2); 5.88–
6.03 (1H, m, CHvCH2); 7.51 and 7.59 (2£2H, 2£d,
J¼8.3 Hz, C6H4); 9.1 (2H, broad s, þNH2). 13C NMR
(68 MHz, DMSO): d 48.34 and 48.39 (NHCH2 and
C6H4C H2); 122.51 (CH2vCH); 128.46 (HCortho); 128.84
(CH2vC H); 130.83 (ClCquat); 132.06 (HCortho); 133.56
(Carom, quat). IR (KBr pellet, cm21): n¼3170–2450; 2399;
1568; 1495; 1434; 1094; 1019. Anal. calcd for C10H13-
BrClN: C 45.74%; H 4.99%; N 5.33%. Found: C 45.64%; H
4.10%; N 5.24%.
3.5.4. N-Allyl-N-(4-methoxybenzyl)amine 17b. This com-
pound has been reported before in the literature, spectro-
metric data however are lacking.23 Yield 71%, colorless oil.
1H NMR (270 MHz, CDCl3): d 1.5 (1H, broad s, NH); 3.26
(2H, d, J¼5.9 Hz, CH2NH); 3.73 (2H, s, C6H5CH2N); 3.80
(3H, s, OCH3); 5.09–5.22 (2H, m, CH2vCH); 5.86–6.00
(1H, m, CH2vCH ); 6.86 (2H, d, J¼8.6 Hz, 2£HCarom);
7.23 (2H, d, J¼8.6 Hz, 2£HCarom). 13C NMR (68 MHz,
CDCl3): d 52.0 (CH2C6H4); 53.0 (CH2NH); 55.7 (OCH3);
114.2 (C H2vCH); 116.6 (2£HCarom); 129.7 (2£HCarom);
130.4 (Cquat); 137.0 (CH2vC H); 159.0 (Cquat). IR (NaCl,
cm21): n¼3317 (NH); 1612 (Cv); 1513; 1463; 1301; 1247;
1176; 1036. MS (70 eV) m/z (%): 177 (Mþ, 33); 149 (10);
121 (100); 83 (58); 56 (10).
3.5.8. N-Allyl-N-(4-chlorobenzyl)amine 17d. Yield 79%;
colorless oil. 1H NMR (270 MHz, CDCl3): d 1.5 (1H, broad
s, NH); 3.25 (2H, d£t, J¼5.9, 1.3 Hz, NHCH2CHv); 3.76
(2H, s, C6H4CH2); 5.12 (1H, d£d£t, J¼10.9, 1.7, 1.3 Hz,
CHvC(H)H ); 5.19 (1H, d£d£t, J¼17.2, 1.7, 1.7 Hz,
CHvC(H )H); 5.92 (1H, d£d£t, J¼17.2, 10.9, 5.9 Hz,
CHvCH2); 7.18–7.30 (4H, m, C6H4). 13C NMR (68 MHz,
CDCl3): d 51.66 (NHCH2); 52.43 (C6H4C H2); 116.19
(C H2vCH); 128.48 and 129.50 (HCorthoþmeta); 132.59
(vC–Cl); 136.57 (CH2vC H); 138.74 (Carom, quat). IR
(NaCl, cm21): n¼3315 (NH); 1643; 1597; 1491; 1453
(CvC). MS (70 eV) m/z (%): 182/4 (Mþ; 34); 126/8 (100);
57 (17). Anal. calcd for C10H12ClN: C 66.12%; H 6.66%; N
7.71%. Found: C 66.01%; H 6.75%; N 7.62%.
3.5.5. N-Allyl-N-(4-bromobenzyl)amine hydrobromide
17c.HBr. Yield 86%; white crystals; mp 195.8–196.28C.
1H NMR (270 MHz, CDCl3): d 3.46 (2H, d, J¼6.9 Hz,
CH2NH2); 4.02 (2H, s, C6H5CH2N); 5.40–5.52 (2H, m,
CH2vCH); 6.00–6.15 (1H, m, CH2vCH ); 7.48 and 7.53
(each 2H, each d, J¼8.6 Hz, HCorthoþmeta); 9.5 (2H, broad s,
þNH2). 1H NMR (270 MHz, DMSO): d 3.62 (2H, d,
J¼6.6 Hz, CH2NH2); 4.14 (2H, s, C6H5CH2N); 5.40–5.51
(2H, m, CH2vCH); 5.88–6.03 (1H, m, CH2vCH ); 7.50
and 7.65 (each 2H, each d, J¼8.3 Hz, HCorthoþmeta); 9.2
(2H, broad s, þNH2). 13C NMR (68 MHz, DMSO): d
48.43 (C H2C6H4 and CH2NH); 122.31 (Cquat); 122.32
(CH2vCH); 128.73 (CH2vC H); 131.07 (Cquat); 131.39
and 132.38 (HCorthoþmeta). IR (KBr pellet, cm21): n¼3070–
2500; 2411; 1576; 1492; 1432; 1074. Anal. calcd for
C10H13Br2N: C 39.12%; H 4.27%; N 4.56%. Found: C
39.02%; H 4.35%; N 4.65%.
3.5.9. N-Allyl-N-(3-cyclohexen-1-yl-methyl)amine hydro-
bromide 17e.HBr. Flash chromatography with CH2Cl2/
MeOH: 9/1, Rf¼0.15. Yield 78%; light yellow waxy solid.
1H NMR (270 MHz, CDCl3): d 1.32–1.46 and 1.81–1.99
(overlap) (2£1H, 2£m, CH(H ) and CH(H)); 2.09 (2H,
broad s, CH2CHvCH (overlap)); 1.81–1.99 (overlap) and
2.16–2.36 (2£1H, 2£m, CH(H) and CH(H )); 2.16–2.36
(1H, m (overlap), CHCH2N); 2.86 (2H, d, J¼6.6 Hz,
CHCH2N); 3.68 (2H, d, J¼6.9 Hz, NHCH2CHv); 5.08
(1H, d£d£t, J¼10.1, 2.0, 1.6 Hz, CHvC(H )H); 5.17 (1H,
d£d£t, J¼17.2, 1.6, 1.6 Hz, CHvC(H)H ); 5.67 (2H, broad
s, CHvCH); 5.91 (1H, d£d£t, J¼17.2, 10.1, 5.9 Hz,
CHvCH2); 6.9 (2H, broad s, NHþ2 ). 13C NMR (68 MHz,
CDCl3): d 24.04 (C H2CHvCH); 26.31 (CHCH2CH2);
3.5.6. N-Allyl-N-(4-bromobenzyl)amine 17c. Yield 70%;
colorless oil. 1H NMR (270 MHz, CDCl3): d 1.70 (1H,
broad s, NH); 3.24 (2H, d£t, J¼5.9, 1.3 Hz, CH2NH); 3.73
(2H, s, C6H5CH2N); 5.11 (1H, d£d£t, J¼10.2, 1.7, 1.3 Hz,
CHvC(H)H ); 5.18 (1H, d£d£t, J¼17.2, 1.7, 1.7 Hz,
CHvC(H)H); 5.85–5.95 (1H, d£d£t, J¼17.2, 10.2,
5.9 Hz, CHvCH2); 7.19 and 7.43 (each 2H, each d,
J¼8.4 Hz, HCorthoþmeta). 13C NMR (68 MHz, CDCl3): d
51.52 (CH2C6H4); 52.33 (CH2NH); 116.10 (CH2vCH);
120.58 (Cquat); 129.76 and 131.30 (HCorthoþmeta); 136.42
29.47
(CH2vCHC H2NH);
(CHvCHCH2);
30.93 (C HCH2);
(CHCH2NH);
50.48
124.04
51.73
(C H2vCH); 124.71 and 126.95 (C HvC H); 128.17
(CH2vC H). IR (NaCl, cm21): n¼3414; 1651 (CvC).
Anal. calcd for C10H18BrN: C 51.73%; H 7.81%; N 6.03%.
Found: C 51.55%; H 7.92%; N 6.13%.

7152
K. Abbaspour Tehrani et al. / Tetrahedron 58 (2002) 7145–7152
States. de Mayo, P., Ed.; Academic: New York, 1980. (c) Felix,
N. M.; Schlegel, H. B.; Martin, N. J. Org. Chem. 1996, 61,
8547–8550. (d) Venkat, K.; Viresh, H. R. J. Org. Chem. 1997,
62, 1572–1573. (e) Daniel, J. P. J. Org. Chem. 1996, 61,
252–256. (f) Derek, C. N. Chem. Soc. Rev. 1993, 347–359.
(g) Martin, N.; Daryl, L. C. J. Am. Chem. Soc. 1994, 116,
9753–9754. (h) Frederick, E. Z.; Anders, K. P. J. Org. Chem.
1995, 60, 2666–2667.
3.5.10. N-Allyl-N-(3-cyclohexen-1-yl-methyl)amine 17e.
Yield 73%. These spectra are in accordance with the
literature data.24 For the sake of completeness full spectro-
scopic data are reported here. 1H NMR (270 MHz, CDCl3):
d 1.15–1.35 (2H, m, CH(H) and NH); 1.65–1.81 (3H, m,
2£CH(H) and CH2CH ); 2.00–2.15 (3H, m, CHCH2CHv
and CH(H )); 2.53 (2H, d, J¼6.3 Hz, CHCH2N); 3.25 (2H,
d£d, J¼5.9, 1.3 Hz, NHCH2CHv); 5.08 (1H, d£d£t, J¼
10.1, 2.0, 1.6 Hz, CHvC(H)H); 5.17 (1H, d£d£t, J¼17.2,
1.6, 1.6 Hz, CHvC(H)H ); 5.67 (2H, broad s, CHvCH );
5.91 (1H, d£d£t, J¼17.2, 10.1, 5.9 Hz, CHvCH2). 13C
NMR (68 MHz, CDCl3): d 24.92 (C H2CHvCH); 27.04
(CHCH2CH2); 30.10 (CHvCHC H2); 33.96 (C HCH2);
53.72 (CH2vCHCH2NH); 55.40 (CHC H2NH); 115.85
(C H2vCH); 126.13 and 127.11 (C HvC H); 137.00
(CH2vCH). IR (NaCl, cm21): n¼3401; 3023; 2926;
1650; 1456; 1378; 1195; 1075; 995; 940; 940; 1670
(CvN); 1652 (CvC). MS (70 eV) m/z (%): 151 (Mþ; 3);
136 (2); 122 (2); 109 (10); 108 (4); 94 (4); 79 (8); 70 (100);
68 (6); 56 (3).
2. Dowd, P.; Zhang, W. Chem. Rev. 1993, 93, 2019–2115.
3. Barton, D. H. R.; Motherwell, R. S. H.; Motherwell, W. B.
J. Chem. Soc., Perkin Trans. 1 1981, 2363–2367.
4. Johns, A.; Murphy, A. Tetrahedron Lett. 1988, 29, 837–840.
5. (a) Clive, D. L. J.; Deigneault, S. J. Org. Chem. 1991, 56,
3801–3814. (b) Newcomb, M.; Glenn, A. G. J. Am. Chem.
Soc. 1989, 111, 275–277. (c) Destabel, C.; Kilburn, J. D.;
Knight, J. Tetrahedron 1994, 50, 11267–11288. (d) Weng,
W. W.; Luh, T. J. J. Org. Chem. 1993, 58, 5574–5575.
(e) Hariharan, V.; Marc, M. G. J. Org. Chem. 1995, 60,
1053–1059.
6. (a) Dickinson, J. M.; Murphy, J. A. Tetrahedron 1992, 48,
1317–1326. (b) Brian, A. M.; Richard, C. T. Tetrahedron Lett.
1999, 40, 4873–4876. (c) Schwan, A. L.; Refvik, M. D.
Tetrahedron Lett. 1993, 34, 4901–4904.
3.5.11. N-Tosylallylamine 17f.20,25 Since no spectra have
been published in the literature full spectroscopic data are
given here. Crude yield 93%; white solid; mp 63–648C.
After Kugelrohr distillation the yield was 57%; bp 170–
1808C/0.1 mmHg. 1H NMR (270 MHz, CDCl3): d 2.44 (3H,
s, CH3); 3.59 (2H, t, J¼5.9 Hz, CH2NH); 4.82 (1H, broad s,
NH); 5.08–5.82 (2H, m, CH2vCH); 5.66–5.80 (1H, m,
CH2vCH ); 7.32 (2H, d, J¼8.0 Hz, C6H4); 7.78 (2H, d,
J¼8.0 Hz, C6H4). 13C NMR (68 MHz, CDCl3): d 21.50
(CH3); 45.71 (CH2NH); 117.53 (CH2vCH); 127.09 (2£
HCarom); 129.72 (2£HCarom); 133.03 (CH2vC H); 136.94
(Cquat); 143.42 (Cquat). IR (NaCl, cm21): n¼3283; 1601;
1415; 1153; 1091. MS (70 eV) m/z (%): 211 (Mþ, 45); 155
(81); 139 (44); 120 (46); 105 (35); 91 (100).
7. De Smaele, D.; Bogaert, P.; De Kimpe, N. Tetrahedron Lett.
1998, 39, 9797–9800.
8. De Kimpe, N.; Jolie, R.; De Smaele, D. J. Chem. Soc., Chem.
Commun. 1994, 121–122.
9. De Kimpe, N.; De Smaele, D.; Bogaert, P. Synlett 1994, 4,
287–288.
10. Pak, C. S. Korean-Hungarian Collect., Conf. Proc. 1999,
69–73.
11. Madabhushi, S.; Ashok, K. B.; Narender, R. Tetrahedron Lett.
1998, 39, 2847–2850.
12. Pak, C. S.; Kim, T. H.; Ha, S. J. J. Org. Chem. 1998, 63,
10006–10010, and references cited therein.
13. Hutchins, R. O.; Suchismita, Z. R. E.; Taffer, I. M. Synth.
Commun. 1989, 19, 1519–1522.
3.5.12. N-Mesylallylamine 17g.20,25 Since no spectra have
been published in the literature full spectroscopic data are
given here. Yield 91%; colorless oil. After Kugelrohr
distillation the yield was 81%; bp 104–1078C/0.25 mmHg.
1H NMR (270 MHz, CDCl3): d 2.98 (3H, s, CH3); 3.76 (2H,
t, J¼4.6 Hz, CH2NH); 4.95 (1H, broad s, NH); 5.19–5.35
(2H, m, CH2vCH); 5.80–5.94 (1H, m, CH2vCH ). 13C
NMR (68 MHz, CDCl3): d 40.38 (CH3); 45.27 (CH2NH);
117.25 (C H2vCH); 133.35 (CH2vC H). IR (NaCl, cm21):
n¼3292; 1647; 1434; 1413; 1314.
14. Lee, E.; Lee, G. H.; Pak, C. S. J. Org. Chem. 1993, 58,
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The authors are indebted to the ‘Fund for Scientific
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I.W.T. and Ghent University for financial support.
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