The effective preparation of secondary amines bearing a vinylsilane functionality via the reaction of primary amines with α-chlorine- substituted allylsilanes catalysed by CuCl

Article abstract of DOI:10.3184/030823407X237795

The reaction of α-chlorine-substituted allylsilanes with primary amines was promoted by CuCl to result in the selective formation of secondary amines bearing the vinylsilane functionality by a probable S_N2′ -allylation keeping the silyl group intact.

Full text of DOI:10.3184/030823407X237795

464 RESEARCH PAPER
AUGUST, 464–467
JOURNAL OF CHEMICAL RESEARCH 2007
The effective preparation of secondary amines bearing a vinylsilane
functionality via the reaction of primary amines with a-chlorine-
substituted allylsilanes catalysed by CuCl
Makoto Kozuka and Michiharu Mitani*
Department of Chemistry and Material Engineering, Faculty of Engineering, Shinshu University, Wakasato 4-17-1, Nagano 380-8551,
Japan
The reaction of a-chlorine-substituted allylsilanes with primary amines was promoted by CuCl to result in the
selective formation of secondary amines bearing the vinylsilane functionality by a probable SN2'-allylation keeping
the silyl group intact.
Keywords: vinylsilane, allylsilane, copper catalyst, secondary amine
The preparation of secondary amines has commonly been
NH2
SiMe3
accomplished by the reactions of primary amines with a range
of electrophiles including alkyl halides. Alkylated secondary
amines, however, tend to undergo further alkylation because
of their enhanced nucleophilicity compared with that of
the parent primary amines. Thus, primary amines usually
incline to the formation of a complex mixture by multi-
alkylation caused by reaction with electrophiles. Therefore,
the selective formation of secondary amines has necessitated
some manipulation in order to avoid multi-alkylation, such as
the introduction of a protecting group on the nitrogen atom,1
the use of primary amines in a large excess,2 the effecting of
reactions via π-allylpalladium complexes,3 and employment
of a method utilising the intermediary generation of a reactive
amide anion species.4
We have recently reported that a CuCl catalyst promoted
the formation of the three-component coupling products of
primary amines with a-halogen-substituted allylsilanes and
electrophiles such as electron-deficient olefins, alkyl halides,
alkyl tosylates or epoxides.5 In the present investigation,
we have shown that the selective formation of secondary
amines with an allyl group is readily brought about by the
CuCl-catalysed reaction of primary amines with a-chlorine-
substituted allylsilanes in the absence of another electrophile.
A mixture of copper(II) perchlorate and copper metal has
been reported to promote the reaction of allyl chlorides
with amines to form allyl amines.6 In this previous method,
however, use of the copper promoter in an equivalent amount
was necessary, and the concomitant formation of diallylated
amines in large amounts occurred. Allylamines are an
interesting class of compounds leading to useful synthetic
intermediates7 along with their physiological properties.8
Furthermore, the carbon–carbon double bond of the allyl group
in the obtained secondary amines is substituted with a silyl
group to constitute a vinylsilane functionality. Vinylsilanes
are building blocks that allow versatile transformations by
reactions with a range of electrophiles,9 e.g. acyl halides to
form conjugated enones.
HN
SiMe3
Additive
+
Cl
1a
2a
Scheme 1
TiCl4 are destroyed with protic compounds containing a N–H
or O–H bond. Actually, the reaction of 1a and aniline in the
presence of TiCl4 in a t-BuOH or CH2Cl2 solution resulted
in no formation of 2a along with recovery of 1a (Table 1,
runs 2 and 3, Scheme 1). The reaction in the presence of
B(OMe)3 also failed to give the enhanced formation of 2a
compared with the reaction without a promoter (Table 1,
run 4). Next, copper(I) chloride was examined, resulting in
the selective formation of 2a (93%) along with accelerated
consumption of 1a. The catalytic activity of the copper(I)
halide for the selective formation of 2a proved to descend in
the order chloride, bromide and iodide (Table 1, runs 5–7),
and copper(II) chloride afforded a low yield of 2a (Table 1,
run 8). Furthermore, the reaction using a palladium catalyst,
in which the formation of the allyl amine derivatives via
a π-allyl complex might be expected,3 was examined. The
result after the reaction in 200 min was only recovery of
1a or the production of 2a in a trace amount (Table 1, runs
9–11). From the above-mentioned results, it seems certain
that copper(I) halide, especially chloride, does not diminish
the nucleophilicity of the amine by formation of a complex,
but rather it enhances the susceptibility of the a-chlorine-
substituted allylsilane to nucleophilic attack by the amine.
Table 1 Effect of metallic species on the reaction of 1a and
anilinea
Run No. Additive
solvent
Time/minb 2acYield/%d
1
2
none
TiCl4
TiCl4
t-BuOH
t-BuOH
CH2Cl2
t-BuOH
t-BuOH
r-BuOH
t-BuOH
t-BuOH
DMF
700
100
100
700
20
12
Initially,
(1-chloro-2-methyl-2-propenyl)trimethylsilane
0
0
1a was subjected to the reaction with aniline (3 equiv.) in a
t-BuOH solution in the absence of a promoter as a control
experiment. The result was a sluggish consumption of 1a
(700 min) and formation of the secondary amine 2a, i.e., N-
(2-methyl-3-trimethylsilyl-2-propenyl)aniline in a low yield
(12%) (Table 1, run 1). Thus, activation of 1a by a Lewis acid
seems to be requisite for the effective allylation of aniline
with 1a. However, common Lewis acids may not bring about
activation of halides owing to the complex-formation with
amines and, furthermore, halogen-containing ones such as
3
4
B(OMe)3
CuCl
CuBr
CuI
12
5
93(92)e
6
20
65
20
25
7
7
0
7
20
8
CuCl2
20
f
9
Pd(OAc)2f
Pd(OAc)2f
Pd(OAc)2
200
200
200
10
11
t-BuOH
CH3CN
aReaction conditions; 1a (1 mmol), aniline (3 mmol), additive
(0.2 mmol), solvent (2.5 ml). bTime at which 1a was consumed.
cA 3/1 mixture of (E) and (Z) stereoisomers. dDetermioned by
GC analysis. eDetermined by column chromatography isolation.
fIn the presence of PPh3 as a ligand.
* Correspondent. E-mail: mitanim@shinshu-u.ac.jp
PAPER: 07/4699

JOURNAL OF CHEMICAL RESEARCH 2007 465
R1
R1
R1
SiMe3
SiMe3
N
R2
CuCl
SiMe3
R2NH2
Me3Si
+
+
+
R1
R1
R2NH
R2NH
X
1
a
b
c
X
R1
Cl Me
3
4
2
Cl
Br
H
H
Scheme 2
We next investigated the effects of the molar ratio of aniline to
1a on the formation of 2a. While use of an equivalent amount
gave only a moderate yield of 2a (48%), use of aniline in two
times excess brought about an almost quantitative yield of 2a
(92%).
The reactions of some a-halogen-substituted allylsilanes
with a range of amines were performed under the best
conditions examined above, i.e., use of 2 equiv. of an amine
and a CuCl catalyst (0.1 equiv.) in a t-BuOH solution. The
results are collected in Table 2 (Scheme 2).
(pKa = 2.65) and m-anisidine (pKa = 4.23) compared with
aniline (pKa = 4.63).10 Next, alkyl amines instead of aromatic
amines were subjected to the reaction with 1. As a result, the
reactions of 1a with benzylamine, and 1b with ethanolamine
gave the products of type 2 in good yields, although formation
of doubly alkylated tertiary amines 4 in trace amounts was
observed (runs 12 and 13). Furthermore, the reaction of the a-
bromine-substituted allylsilane 1c with ethanolamine brought
about diminution in the yield of the product of type 2 and
increase of the product of type 4, compared with the reaction
of the a-chlorine analogue 1b (runs 13 and 14). While 1c
disappeared after 3 hours in the reaction with ethanolamine in
the absence of CuCl, 1b was not consumed without CuCl in a
reaction time of 3 hours (runs 16 and 17).
Finally, 2-methylallyl chloride was subjected to the CuCl-
catalysed reaction with aniline in order to evaluate the effect
of the silyl substituent. The result was promotion of multi-
allylation compared with the reaction of 1a, as revealed in
Scheme 3.
The silyl group in 1 appears to allow avoidance of multi-
alkylation and promote the selective formation of the
secondary amine.
(1-Chloro-2-propenyl)trimethylsilane
1b
gave
the
corresponding secondary amine in an almost quantitative
yield by the reaction with aniline in 20 min., similar to the
case using 1a (runs 1–2). The reactions of 1a with aniline
derivatives bearing alkyl substituents or the amines of aromatic
systems other than benzene (i.e., 2-naphthylamine and 2-
aminofluorene) also gave the products of type 2 in excellent
to good yields (runs 3–7). In the reaction of 1a with aniline
derivatives bearing an electron-withdrawing group (i.e., nitro
or cyano), however, a secondary amine 3 based on introduction
of a 2-methylallyl group without a silyl group was selectively
obtained (runs 8 and 9). The basicities of the aniline derivatives
bearing these electron-withdrawing groups are low. Thus,
hydrogen chloride generated by the reaction with 1a is rather
hard to trap with these amines and may promote desilylation
of the product of type 2 to result in the formation of 3. Also,
in the reactions of 1a with o-chloroaniline or m-anisidine, the
products of type 3 were formed, although in low yields, along
with the products of type 2. Formation of 3 in these reactions
probably results from the lower basicities of o-chloroaniline
Experimental
1H and 13C NMR spectra were recorded on a JNM QX400 (400 and
100 MHz) spectrometer for solutions in CDCl3 using TMS as internal
standard (δ = 0). MS and HRMS were obtained using Shimadzu
GCMS-QP5000 and Hitachi M-80B GC-MS instruments equipped
with a 30 m DB-1 columun.
Table 2 Reaction of a-chlorine substituted allylsilanes with aminesa
Run No.
1
R2NH2
Time/minb
Yield/%c
2
3
4
1
2
a
b
a
a
a
a
a
a
a
a
a
a
b
c
PhNH2
20
20
25
25
35
45
20
35
40
15
25
40
60
40
180
180l
ad
b
92
90
90
95
90
94
90
0
0
0
PhNH2
0
0
0
3
4-EtC6H4NH2
2,4-Me2C6H3NH2
2,4,6-Me3C6H2NH2
2-naphthylamine*
2-aminofluorene
4-NO2C6H4NH2
4-NCC6H4NH2
2-ClC6H4NH2
3-MeOC6H4NH2
PhCH2NH2
HO(CH2)2NH2
HO(CH2)2NH2
HO(CH2)2NH2
HO(CH2)2NH2
cd
de
ef
fd
gh
h
0
4
0
0
5
0
0
6
0
0
7g
8
0
0
88
85
31
25
0
0
9i
i
0
0
10i
11
12
13
14
15k
16k
jd
62
72
83
88
61
65
0
0
kj
lf
0
1.5
1
m
m
m
m
0
0
10
13
0
c
0
b
0
aReaction conditions; 1a (1 mmol), amine (2 mmol), CuCl (0.1 mmol), t-BuOH (2.5 ml) under reflux. bTime at which 1 was consumed.
cDetermined by column chromatography isolation. dE/Z = 3/1. eE/Z = 2/1. fE/Z = 1/1. gConditions; 1a (1 mmol)/amine (2 mmol)/CuCl
(0.1 mmol)/EtOH (12 ml). hE/Z = 5/1. iConditions; 1a (0.5 mmol)/amine (2 mmol)/CuCl (0.1 mmol)/EtOH (2.5 ml). jE/Z = 4/1. kWithout
CuCl. l1b was not consumed.
PAPER: 07/4699

466 JOURNAL OF CHEMICAL RESEARCH 2007
NH2
HN
N
Cl
+
CuCl
+
t-BuOH
50%
28%
Scheme 3
6.43–7.44 (m, 7H, benzene ring); 13C NMR δ –0.3, 20.1, 24.9, 36.5,
49.3, 49.7, 108.6, 111.4, 117.7, 119.9, 124.0, 125.9, 127.7, 131.3,
141.4, 141.6, 144.4, 147.3, 152.0; MS (GC-EI) m/z (%) component A
= 307 (M+, 94), 292 (59), 266 (51), 234 (33), 194 (64), 180 (36), 165
(47), 73 (100): component B = 307 (M+, 74), 292 (25), 266 (18), 234
(25), 194 (100), 180 (29), 165 (37), 73 (51); (Found: M+ 307.1785.
C20H25NSi requires 307.1755).
CAUTION: The importation, manufacture and use of 2-
naphthylamine for all purposes is prohibited in the UK due
to its potent human carcinogenicity (COSHH Regulations).
An amine (2 mmol), 1 (1 mmol), CuCl (0.01 g, 0.1 mmol) and tert-
BuOH (2.5 mmol) were added to a flask. The resulting solution was
stirred under reflux. The reaction mixture was then poured into H2O
and extracted with Et2O. After the solvent was mostly removed
under reduced pressure, the residue was subjected to column
chromatography using hexane/ethyl acetate (1:2) as an eluent.
1
(3h): H NMR δ 1.71 (s, 3H, MeC=C), 2.95 (s, 1H, NH), 3.71
(s, 2H, CH2C=C), 4.86 (s, 2H, C=CH2), 6.46 (d, J = 8.4 Hz, 2H,
aromatic C(2) and C(6)H), 7.99 (d, J = 8.4 hz, aromatic C(3) and
C(5)H); 13C NMR δ 20.3, 49.2, 111.1, 111.6, 126.2, 137.6, 140.6,
153.0; MS (DI) m/z (%) 192 (M+, 45), 177 (25), 151 (100), 130
(14), 105 (45), 76 (15), 55 (30); (Found: M+ 192.0917. C10H12N2O2
requires 192.0898).
1
(2a, E and Z mixture): H NMR δ 0.05 (s, 9H, SiMe3), 1.74 and
1.82 (s, 3H, MeC=CSi), 3.57 and 3.66 (s, 2H, CH2C=CSi), 4.78 (s,
1H, NH), 5.40 and 5.43 (s, 1H, C=CHSi), 6.52–7.10 (m, 5H, phenyl);
13C NMR δ –0.3, 19.6, 25.2, 49.3, 53.1, 112.5, 117.9, 128.1, 128.7,
148.0, 152.3; MS (GC-EI) m/z (%) component A = 219 (M+, 27),
204 (42), 178 (22), 146 (49), 106 (100), 73 (65, 59 (28): component
B = 219 (M+, 19), 204 (22), 178 (11), 146 (37), 106 (100), 73 (49),
59 (19); (Found: M+ 219.1473. C13H21NSi requires M, 219.1443).
(3i): 1H NMR δ 1.63 (s, 3H, MeC=C), 3.58 (s, 2H, CH2C=C), 4.42
(s, 1H, NH), 4.78 (s, 2H, C=CH2), 6.42 (d, J = 8.9 Hz, 2H, aromatic
C(2) and C(6)H), 7.26 (d, J = 8.9 Hz, aromatic C(3) and C(5)H); 13
C
NMR δ 20.1, 49.0, 109.5, 111.6, 122.3, 114.5, 133.7, 133.9, 141.3;
MS (GS-EI) m/z (%) 172 (M+, 62), 157 (71), 131 (100), 102 (19), 55
(23); (Found: M+ 172.0971. C11H12N2 requires 172.0999).
1
(2b): H NMR δ 0.05 (s, 9H, SiMe3), 3.68 (d, J = 4.8 Hz, 2H,
CH2CH=CSi), 3.90 (s, 1H, NH), 5.84 (d, J = 18.8 Hz, 1H, C=CHSi),
6.04 (dt, 2J = 18.8 Hz, 3J = 4.8 Hz, 1H, CH=CSi), 6.49–7.10 (m, 5H,
phenyl); 13C NMR δ –0.4, 48.5, 112.6, 117.0, 128.6, 130.6, 142.6,
144.9; MS (GC-EI) m/z (%) 205 (M+, 30), 190 (28), 132 (100), 106
(81), 77 (46), 73 (68), 59 (46); (Found: M+ 205.1283. C12H19NSi
requires M, 205.1285).
(2j, E and Z mixture): 1H NMR δ 0.06 (s, 9H, SiMe3), 1.68 and 1.79
(s, 3H, MeC=CSi), 3.59 and 3.67 (s, 2H, CH2C=CSi), 4.23 (s, 1H,
NH), 5.41 and 5.44 (s, 1H, C=CHSi), 6.46–7.13 (m, 4H, aromatic);
13C NMR δ –0.86, 20.0, 24.9, 49.1, 52.4, 110.5, 111.0, 116.6, 118.4,
127.1, 128.4, 143.6, 151.3; MS (GC-EI) m/z (%) component A = 255
[M(Cl37)+, 8], 253 [M(Cl35)+, 21], 238 (46), 180 (44), 140 (53), 73
(100), 59 (38): component B = 255 [M(Cl37)+, 10], 253 [M(Cl35)+,
28], 238 (33), 180 (53), 140 (76), 73 (100), 59 (30); [Found: M(Cl35)+
253.1039. C13H20NSiCl requires 253.1052].
1
(2c, E and Z mixture): H NMR δ 0.05 (s, 9H, SiMe3), 1.05 (t,
J = 7.6 Hz, 3H, CH3CH2), 1.68 and 1.77 (s, 3H, MeC=CSi), 2.40
(q, J = 7.6 Hz, CH2CH3), 3.45 (s, 1H, NH), 3.49 and 3.59 (s, 2H,
CH2C=CSi), 5.34 and 5.40 (s, 1H, C=CHSi), 6.42 (d, J = 8.4 Hz, 2H,
aromatic C(2)H), 6.87 (d, J = 8.4 Hz, 2H, aromatic C(3)H); 13C NMR
δ –0.3, 15.6, 19.3, 24.9, 27.5, 49.3, 53.2, 112.3, 127.5, 132.3, 145.7,
152.3; MS (GC-EI) m/z (%) component A = 247 (M+, 38), 232 (56),
206 (35), 174 (35), 134 (1009, 83 (31), 73 (87), 59 (42): component
B = 247 (M+, 18), 232 (17), 206 (10), 174 (20), 134 (100), 83 (18), 73
(46), 59 (25); (Found: M+ 247.1770. C15H25NSi requires 247.1755).
(2d, E and Z mixture): 1H NMR δ 0.05 (s, 9H, SiMe3), 1.70
and 1.79 (s, 3H, MeC=CSi), 1.95 (s, 3H, aromatic C(4)Me), 2.09
(s, 3H, aromaticC(2)Me), 3.25 (s, 1H, NH), 3.55 and 3.62 (s, 2H,
CH2C=CSi), 5.36 and 5.40 (s, 1H, C=CHSi), 6.40 (d, J = 8.4 Hz, 1H,
aromatic C(2)H), 6.74 (s, 1H, aromatic C(3)H), 6.79 (d, J = 8.4 Hz,
1H, aromatic C(3)H); 13C NMR δ –0.3, 17.1, 19.3, 20.0, 25.0, 49.3,
53.1, 109.4, 121.3, 125.5, 126.7, 130.2, 143.5, 152.4; MS (GC-EI)
m/z (%) component A = 247 (M+, 36), 232 (31), 206 (8), 190 (11),
174 (55), 134 (100), 73 (64), 59 (37): component B = 247 (M+, 22),
232 (10), 206 (5), 190 (5), 174 (22), 134 (100), 73 (57), 59 (25);
(Found: M+ 247.1759. C15H25NSi requires 247.1755).
1
(2k, E and Z mixture): H NMR δ 0.05 (s, 9H, SiMe3), 1.68 and
1.77 (s, 3H, MeC=CSi), 3.51 (s, 1H, NH), 3.58 and 3.61 (s, 2H,
CH2C=CSi), 3.61 (s, 3H, OMe), 5.34 and 5.39 (s, 1H, C=CHSi),
6.04 (s, 1H, aromatic C(2)H), 6.09–6.95 (m, 3H, aromatic C(4),
C(5) and C(6)H); 13C NMR δ –1.0, 19.5, 24.9, 49.0, 52.9, 54.5, 98.2,
102.0, 105.4, 127.8, 129.3, 149.1, 152.0, 160.0; MS (GC-EI) m/z (%)
component A = 249 (M+, 40), 234 (50), 176 (68), 136 (100), 73 (85):
component B = 249 (M+, 30), 234 (25), 176 (42), 136 (100), 73 (48);
(Found: M+ 249.1559. C14H23NOSi requires 249.1548).
1
(2l, E and Z mixture): H NMR δ 0.07 (s, 9H, SiMe3), 1.67 and
1.79 (s, 3H, MeC=CSi), 3.06 and 3.14 (s, 2H, CH2C=CSi), 3.61 (s,
2H, PhCH2N), 3.98 (s, 1H, NH), 5.25 and 5.32 (s, 1H, C=CHSi),
7.18 (s, 5H, phenyl); 13C NMR δ –1.0, 19.9, 25.0, 53.0, 54.2, 58.2,
126.4, 127.3, 127.7, 128.0, 140.1, 153.2; MS (GC-EI) m/z (%)
component A = 218 (6), 178 (10), 160 (14), 142 (35), 120 (24), 91
(100), 73 (68): component B = 218 (5), 178 (10), 160 (15), 142 (25),
120 (32), 91 (100), 73 (37); MS (GC-CI) m/z component A = 234
(M + 1)+: component B = 234 (M + 1)+; [Found: (M – Me)+ 218.1369.
C13H20NSi requires 218.1364].
(2e, E and Z mixture): 1H NMR δ 0.05 (s, 9H, SiMe3), 1.75 and 1.77
(s, 3H, MeC=CSi), 2.11 (s, 3H, aromatic C(4)Me), 2.19 (s, 6H, aromatic
C(2) and C(6)Me), 3.31 and 3.44 (s, 2H, CH2C=CSi), 5.30 and 5.51 (s,
1H, C=CHSi), 6.70 (s, 2H, aromatic C(3) and C(5)H); 13C NMR δ –0.4,
18.1, 18.4, 20.4, 25.4, 53.8, 57.9, 123.1, 127.7, 129.0, 130.7, 143.4,
152.3; MS (GC-EI) m/z (%) component A = 261 (M+, 50), 246 (29),
188 (74), 148 (100), 134 (59), 91 (24), 73 (55), 59 (37): component B =
261 (M+, 20), 246 (7), 188 (30), 105 (100), 134 (28), 91 (13), 73 (30),
59 (24); (Found: M+ 261.1934. C16H27NSi requires 261.1911).
1
(2m): H NMR δ 0.05 (s, 9H, SiMe3), 2.61 (t, J = 5.6 Hz, 2H,
NCH2CH2OH), 2.80 (s, 2H, OH and NH), 3.08 (d, J = 4.8 Hz, 2H,
NCH2CH=C), 3.53 (2H, J = 5.6 Hz, 2H, NCH2CH2OH, 5.62 (d,
2
3
J = 18.8 Hz, 1H, C=CHSi), 5.83 (dt, J = 18.8 Hz, J = 4.8 Hz, 1H,
CH=CSi); 13C NMR δ –1.0, 50.5, 54.2, 60.6, 123.1, 127.9; MS
(GC-EI) m/z (%) 173 (M+, 8), 158 (10), 142 (36), 128 (17), 73 (100),
59 (42); (Found: M+ 173.3021. C8H19NOSi requires 173.3042).
(2f, E and Z mixture): 1H NMR δ 0.05 (s, 9H, SiMe3), 1.70 and 1.81
(s, 3H, MeC=CSi), 3.61 and 3.71 (s, 2H, CH2C=CSi), 4.30 (s, 1H,
NH), 5.42 and 5.44 (s, 1H, C=CHSi), 6.45–7.61 (m, 7H, naphthyl);
13C NMR δ –0.3, 19.7, 25.2, 49.2, 52.0, 104.0, 117.0, 119.2, 122.8,
124.1, 125.1, 126.0, 128.0, 128.1, 133.7, 142.8, 151.8; MS (GC-EI)
m/z (%) component A = 269 (M+, 67), 254 (42), 196 (62), 156 (46),
127 (25), 92 (40), 73 (100), 59 (49): component B = 269 (M+, 40),
254 (21), 196 (48), 156 (65), 127 (33), 115 (26), 73 (100), 59 (52);
(Found: M+ 269.1578. C17H23NSi requires 269.1597).
Received 14 June 2007; accepted 2 August 2007
Paper 07/4699 doi: 10.3184/030823407X237795
References
1(a) J. Jacobus, M. Raban and K. Mislow, J. Org. Chem., 1968, 33,
1142; (b) P. Nussbaumer, K. Baumann, T. Dechat and M. Harasek,
Tetrahedron, 1991, 47, 4591; (c) M.B. Sassaman, Tetrahedron, 1996,
52, 10835.
2 (a) J.H. Speer and A.J. Hill, J. Org. Chem., 1937, 2, 139;
(b) W.J. Hickinbottom, J. Chem. Soc., 1930, 992.
1
(2g, E and Z mixture): H NMR δ 0.05 (s, 9H, SiMe3), 1.72 and
1.78 (s, 3H, MeC=CSi), 3.51 and 3.60 (s, 2H, CH2C=CSi), 3.62 (s,
2H, fluoren CH2), 3.87 (s, 1H, NH), 5.34 and 5.37 (s, 1H, C=CHSi),
PAPER: 07/4699

JOURNAL OF CHEMICAL RESEARCH 2007 467
3 (a) S.-I. Murahashi, Y. Imada, Y. Taniguchi and Y. Kodera, Terahedron
Lett., 1988, 29, 2973; (b) S.-C. Yang and C.-W. Hung, Synthesis,
1999, 1747.
4 W. Ando and H. Tsumaki, Chem. Lett., 1981, 693.
5 M. Kozuka, A. Inoue, T. Tsuchida and M. Mitani, Adv. Synth. Cat.,
2006, 348, 953.
8 (a) Y. Genisson, M. Mehmandoust, C. Marazano and B.C. Das,
Heterocycles, 1994, 39, 811; (b) P. Jain, H.M. Garraffo, T.F. Spande,
H.J.C. Yeh and J.W. Daly, J. Nat. Prod., 1995, 58, 100.
9 (a) E.W. Colvin, Silicon Reagents in Organic Synthesis, Academic
Press, London, 1988, p. 14; (b) I. Fleming, A. Barbero and D. Walter,
Chem. Rev., 1997, 97, 2063.
6 J.B. Baruah and A.G. Samuelson, Tetrahedron, 1991, 47, 9449.
7 A. Stutz, Angew. Chem., Int. Ed. Engl., 1987, 26, 320.
10 CRC Handbook of Chemistry and Physics, D.R. Lide (ed.),
CRC Press, Boca Raton, 1993, pp.8-43.
PAPER: 07/4699