FeCl3-catalyzed propargylation of aromatic compounds with propargylic acetates

Article abstract of DOI:10.1016/j.tetlet.2006.10.038

A new method for the synthesis of propargylated aromatic compounds is developed. The reaction was carried out at room temperature in the presence of a catalytic amount of FeCl₃ in acetonitrile, high product yields were obtained with excellent r

Full text of DOI:10.1016/j.tetlet.2006.10.038

Tetrahedron Letters 47 (2006) 9143–9146
FeCl -catalyzed propargylation of aromatic compounds with
3
propargylic acetates
*
Zhuang-Ping Zhan, Yuan-Yuan Cui and Hui-Juan Liu
Department of Chemistry and The Key Laboratory for Chemical Biology of Fujian Province,
College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, PR China
Received 29 July 2006; revised 30 September 2006; accepted 8 October 2006
Available online 3 November 2006
Abstract—A new method for the synthesis of propargylated aromatic compounds is developed. The reaction was carried out at
room temperature in the presence of a catalytic amount of FeCl in acetonitrile, high product yields were obtained with excellent
3
regioselectivity and the reaction proceeded smoothly without exclusion of moisture or air.
Ó 2006 Elsevier Ltd. All rights reserved.
Friedel–Crafts alkylation is one of the most important
C–C bond forming reactions, which provides an efficient
synthetic route to numerous functionalized aromatic
compounds possessing special properties. Thus, the
research of this reaction has got much attention, a series
of aromatic substances with various electrophilic sub-
strates such as active carbonyl compounds, epoxides,
and electron-deficient olefins have been extensively stud-
argylation. However, the peculiarity and high cost of
such catalysts are a barrier to their large-scale use.
Therefore, development of a general, efficient, cheap,
and readily available catalyst for propargylation of
aromatic compounds is highly desirable.
Herein, we wish to report an efficient FeCl -catalyzed
3
propargylation of aromatic compounds with propargy-
lic acetates bearing not only a terminal alkyne group
1
ied. However, little attention has been paid to the reac-
3
tion of propargylic alcohol derivatives with aromatic
compounds, despite such reactions playing an important
role in the synthesis of some natural products such as
O-methyldetrol, mimosifoliol, and b-apopicropodophyl-
but also internal alkyne group, sp -C–C bonds were
formed after the propargylation event (Scheme 1). To
the best of our knowledge, there was no report in the
literature on the reaction of propargylic esters with
aromatic compounds. The reaction was carried out at
room temperature in the presence of a catalytic amount
of FeCl3 in acetonitrile. High product yields were
obtained with excellent reaction regioselectivity and
the reaction proceeded smoothly without exclusion of
2
,4
lin and so on. The Nicholas reaction has been known
to be effective for propargylation of aromatic com-
pounds by using a stoichiometric amount of Co (CO) ,
2
8
where several steps are necessary to obtain propargy-
lated products from propargylic alcohols via cationic
+
3
8
propargyl complexes [Co (CO) (propargyl)] . Recently,
moisture or air from the reaction mixture.
2
6
4
5
Toste and co-workers and Uemura and co-workers
have described efficient rhenium [(dppm) ReOCl ] and
3
*
diruthenium [[Cp RuCl(SR)] ] catalyzed propargylation
2
OAc
Nu
of aromatic compounds with propargylic alcohols,
6
5 mol% FeCl3
respectively. In addition, Campagne and co-workers
Ph
+
NuH
Ph
7
CH CN
3
and Dyker and co-workers introduced the gold [NaAu-
R
R
Cl Æ2H O; AuCl ] as an alternative catalyst for the prop-
4
2
3
R = Ph,
NuH =
n-Bu, TMS, H
Keywords: Propargylation of aromatic compounds; Propargylic acet-
ates; Iron(III) chloride.
,
,
O
N
R'
H
*
Corresponding author. Tel.: +86 592 2180318; fax: +86 592
185780; e-mail: zpzhan@xmu.edu.cn
2
Scheme 1.
0040-4039/$ - see front matter Ó 2006 Elsevier Ltd. All rights reserved.
doi:10.1016/j.tetlet.2006.10.038

9144
Z.-P. Zhan et al. / Tetrahedron Letters 47 (2006) 9143–9146
In order to determine the scope and limitation of this
reaction, a series of propargylic acetates with various
aromatic compounds were investigated. First, reactions
of 1,3-diphenylprop-2-ynyl acetate (1a) with various
aromatic compounds were carried out. Typical results
were shown in Table 1. The corresponding propargyl
adducts were obtained in high yields with a complete
regioselectivity (Table 1, entries 1–7). In the cases of
electron-rich arenes such as phenol, b-naphthol, meth-
oxybenzene, 1,3-dimethoxybenzene, and b-methoxy-
a
Table 1. Propargylation of aromatic compounds with propargylic acetates via Scheme 1
c
Entry
R
Nu
Time (h)
0.5
Product
Yields of 2 (%)
1
1a, Ph
HO
2a
91
93
OH
2
1a, Ph
0.5
2b
3
4
1a, Ph
1a, Ph
O
O
0.5
3.0
2c
2d
83
80
O
O
5
1a, Ph
0.5
2e
92
81
6
7
8
9
1a, Ph
0.5
4.0
2.0
3.0
2f
2g
2h
2i
O
b
1a, Ph
60
N
O
1b, TMS
1b, TMS
80
78
O
O
1
1
1
1
1
0
1
2
3
4
1b, TMS
1c, n-Bu
1c, n-Bu
1c, n-Bu
1d, H
5.0
0.5
0.5
1.0
3.0
2j
80
85
93
86
68
O
O
2k
2l
HO
O
2m
2n
OH
15
1d, H
6.0
2o
55
O
a
b
c
The reactions of 1 (1 mmol) with NuH (3 mmol) were carried out in the presence of FeCl
The reaction was carried out at 60 °C.
Isolated yields.
3
(0.05 mmol) in CH
3
CN (2 mL) at room temperature.

Z.-P. Zhan et al. / Tetrahedron Letters 47 (2006) 9143–9146
9145
Acknowledgements
OAc
OH 5 mol% FeCl3
rt, CH CN
HO
R1
+
The project was supported by the National Natural
Science Foundation of China (No. 30572250) and
Natural Science Foundation of Fujian Province of
China (No. C0510002).
3
R1
R2
Ph
R2
Ph
1
1
e (R1, R2 = CH3)
2p (R1, R2 = CH , 1.5 h, 91%)
3
f (R1 = H, R2 = CH3)
2q (R = H, R = CH , no reaction)
1
2
3
References and notes
Scheme 2.
1
2
3
. (a) Zhuang, W.; Gathergood, N.; Hazell, R. G.; J ø´ rgensen,
K. A. J. Org. Chem. 2001, 66, 1009; (b) Lyle, M. P. A.;
Draper, N. D.; Wilson, P. D. Org. Lett. 2005, 7, 901;
(c) Bandini, M.; Cozzi, P. G.; Melchiorre, P.; Umani-
Ronchi, A. Angew. Chem., Int. Ed. 2003, 43, 84; (d) Zhou,
J.; Tang, Y. J. Am. Chem. Soc. 2002, 124, 9030; (e) Evans,
D. A.; Fandrick, K. R.; Song, H. J. J. Am. Chem. Soc. 2005,
naphthalene, the corresponding Friedel–Crafts propar-
gylated products (2a–e) were obtained in 91%, 93%,
8
1
3%, 80%, and 92% isolated yields, respectively (entries
–5). Heterocyclic aromatic compound furan can also be
propargylated with 1a at room temperature, the propar-
gylation occurred selectively at the a-position of furan,
giving the propargylic adduct 2f in 81% isolated yield
1
27, 8942; (f) Jia, Y. X.; Zhu, S. F.; Yang, Y.; Zhou, Q. L.
J. Org. Chem. 2006, 71, 75.
. (a) Andersson, P. G.; Schink, H. E.; Osterlund, K. J. Org.
Chem. 1998, 63, 8067; (b) Botteghi, C.; Corrias, T.;
Marchetti, M.; Paganelli, S.; Piccolo, O. Org. Process
Res. Dev. 2002, 6, 379; (c) Lee, K.-H. Med. Res. Rev. 1999,
19, 569; (d) Gordaliza, M.; Castro, M. A.; Miguel del
Corral, J. M.; Lopez-Vazquez, M. L.; San Feliciano, A.;
Faircloth, G. T. Bioorg. Med. Chem. Lett. 1997, 7, 2781;
(
entry 6). Nevertheless, in the case of pyrrole, longer
reaction time and higher reaction temperature were
required to obtain 2g in 60% isolated yield (entry 7).
In all cases, propargylation occurred selectively at the
electron-rich position of the aromatic compounds.
These results indicated that the reaction proceeded
electrophilically.
(
e) Andrews, R. C.; Teague, S. J.; Meyers, A. I. J. Am.
Chem. Soc. 1988, 110, 7854.
. Review articles: (a) Nicholas, K. M. Acc. Chem. Res. 1987,
On the other hand, the reaction could also be extended
to propargyl acetates bearing a variety of alkyne substi-
tuents. Variation in the alkyne substituent from an aryl
to an alkyl or trimethylsilyl (1a–c) was well tolerated,
without noticeable difference observed in the reaction
temperature, time, and product yield. Gratifyingly,
2
0, 207; (b) Caffyn, A. J. M.; Nicholas, K. M. In
Comprehensive Organometallic Chemistry II; Abel, E. W.,
Stone, F. G. A., Wilkinson, J., Eds.; Pergamon Press:
Oxford, 1995; Vol. 12, p 685, Chapter 7.1; (c) Green, J. R.
Curr. Org. Chem. 2001, 5, 809; (d) Teobald, B. J. Tetra-
hedron 2002, 58, 4133; (e) Kuhn, O.; Rau, D.; Mayr, H. J.
Am. Chem. Soc. 1998, 120, 900; (f) Nicholas, K. M.;
Mulvaney, M.; Bayer, M. J. Am. Chem. Soc. 1980, 102,
1
-phenylprop-2-ynyl acetate (1d) bearing a terminal
alkyne substituent was successfully arylated in moderate
yields and no polymerization was detected, although
compared to internal alkyne substituent, longer reaction
time was required (entries 14 and 15). Nonbenzylic
propargyl acetates also participated in the aromatic
propargylation. Iron(III)-catalyzed coupling of tertiary
aliphatic acetate (1e) with b-naphthol allowed for the
construction of a quaternary carbon (Scheme 2, 2p);
however, secondary aliphatic acetate (1f) failed to get
the propargylated aromatic compound after 24 h
2
508.
. Kennedy-Smith, J. J.; Young, L. A.; Toste, F. D. Org. Lett.
004, 6, 1325.
4
5
2
. (a) Nishibayashi, Y.; Inada, Y.; Yoshikawa, M.; Hidai, M.;
Uemura, S. Angew. Chem., Int. Ed. 2003, 42, 1495; (b)
Nishibayashi, Y.; Yoshikawa, M.; Inada, Y.; Hidai, M.;
Uemura, S. J. Am. Chem. Soc. 2002, 124, 11846.
. Georgy, M.; Boucard, V.; Campagne, J. M. J. Am. Chem.
Soc. 2005, 127, 14180.
6
7. Liu, J. H.; Muth, E.; Fl o¨ rke, U.; Henkel, G.; Merz, K.;
(
Scheme 2, 2q). The experimental results suggested a
Sauvageau, J.; Schwake, E.; Dyker, G. Adv. Synth. Catal.
2
006, 348, 456.
. Typical experimental procedure:
a) Preparation of propargylic acetates. Bartels, A.; Mahr-
wald, R.; M u¨ ller, K. Adv. Synth. Catal. 2004, 346, 483.
b) Preparation of propargylated aromatic compounds. A
mechanism through the formation of propargylic cation
intermediate. Unstability of the propargylic cation inter-
mediate clearly made the substitution reaction less
favorable.
8
(
(
typical experimental procedure for the reaction of propar-
gylic acetates with aromatic compounds catalyzed by
5 mol % FeCl3 is described below: to a 5 mL flask, 1,3-
diphenylprop-2-ynyl acetate (1a) (250 mg, 1 mmol), phenol
(282 mg, 3.0 mmol), CH CN (2 mL), and anhydrous FeCl
3 3
(8 mg, 0.05 mmol) were successively added, and then the
mixture was magnetically stirred at room temperature for
In conclusion, we have developed a general and efficient
FeCl -catalyzed propargylation of aromatic com-
3
pounds, leading to the construction of C–C bonds.
The corresponding propargylic adducts were obtained
in high yields with complete regioselectivity. In compar-
ison with rhenium, ruthenium, and gold complexes,
which were used to catalyze the propargylation of
0
.5 h. The solvent was concentrated under reduced pressure
by an aspirator, and then the residue was purified by silica
gel column chromatography (EtOAc/hexane) to afford
aromatic compounds, FeCl as the catalyst offer several
3
relevant advantages including cheapness, commercial
availability, and mild reaction conditions of this trans-
formation. Further investigations for the elucidation of
the detailed reaction mechanism and broadening the
scope of this methodology are currently going on in
our laboratory.
4
-(1,3-diphenylprop-2-ynyl)phenol (2a) as a yellow solid
(
258 mg, 91% yield).
1
13
As for the known compounds, H NMR and C NMR are
provided, data are in accordance with previously reported
results. For the new compounds, H NMR, C NMR, IR,
and elemental analysis data are provided.
1
13

9146
Z.-P. Zhan et al. / Tetrahedron Letters 47 (2006) 9143–9146
4
-(1,3-Diphenylprop-2-ynyl)phenol (2a): Yield 91%. A yel-
(s, 3H), 5.40 (s, 1H), 6.41 (d, 1H, J = 2.4 Hz), 6.48 (dd, 1H,
J = 8.4 and 2.4 Hz), 7.13–7.19 (m, 1H), 7.22–7.28 (m, 2H),
7.35–7.40 (m, 2H), 7.42 (d, 1H, J = 8.4 Hz) ppm; C NMR
1
low solid (mp 82–86 °C). H NMR (CDCl
.91 (br s, 1H), 5.14 (s, 1H), 6.76 (apparent d, 2H,
J = 8.5 Hz), 7.20–7.34 (m, 8H), 7.39–7.49 (m, 4H) ppm;
3
, 400 MHz): d
1
3
4
(CDCl , 100 MHz): d 0.19, 36.5, 55.4, 55.5, 87.4, 98.6,
3
1
3
C NMR (CDCl
3
, 100 MHz): d 42.8, 84.7, 90.4, 115.4,
104.5, 107.8, 122.7, 126.4, 127.7, 128.2, 129.4, 141.9, 157.0,
1
1
1
1
9
6
7
23.4, 126.8, 127.7, 127.9, 128.2, 128.6, 129.1, 131.6, 134.0,
159.9 ppm; IR (film) mmax: 3027, 2169, 1612, 1588, 1503,
À1
41.9, 154.2 ppm; IR (film) mmax: 3353, 3058, 3027, 2216,
1452, 1249, 1036 cm
.
À1
618, 1602, 1509, 1490 cm
.
(3-(Furan-2-yl)-3-phenylprop-1-ynyl)trimethylsilane
(2j):
, 400 MHz): d
0.02 (s, 9H), 4.85 (s, 1H), 6.01 (d, 1H, J = 3.1 Hz), 6.08 (dd,
1
-(1,3-Diphenylprop-2-ynyl)naphthalen-2-ol (2b): Yield
Yield 80%. A clear oil. H NMR (CDCl
3
1
3%. A pale yellow oil. H NMR (CDCl , 400 MHz): d
3
1
3
.27 (s, 1H), 6.38 (s, 1H), 7.16 (d, 1H, J = 8.9 Hz), 7.20–
1H, J = 3.1 Hz and 1.7 Hz), 7.02–7.22 (m, 6H) ppm;
C
.50 (m, 12H), 7.75 (d, 1H, J = 8.9 Hz), 7.80 (d, 1H,
NMR (CDCl , 100 MHz): d 0.0, 38.2, 88.4, 103.7, 106.5,
3
1
3
J = 8.0 Hz), 8.03 (d, 1H, J = 8.6 Hz) ppm; C NMR
CDCl , 100 MHz): d 33.7, 86.0, 88.3, 117.6, 119.1, 122.5,
110.2, 127.3, 127.8, 128.6, 138.6, 142.2, 153.7 ppm; IR (film)
À1
(
mmax: 3063, 3029, 2177, 1603, 1495, 1453, 1076, 843 cm
.
3
1
1
3
1
23.0, 123.3, 126.8, 127.0, 127.2, 128.3, 128.5, 128.7, 128.8,
Anal. Calcd for C16
75.45; H, 7.42.
H18OSi: C, 75.54; H, 7.13. Found: C,
29.6, 129.8, 131.8, 132.3, 139.5, 152.3 ppm; IR (film) mmax
:
À1
420, 3054, 3027, 2217, 1631, 1595, 1520, 1490 cm
.
1-Methoxy-4-(1-phenylhept-2-ynyl)benzene (2k): Yield
1
-(3-(4-Methoxyphenyl)-3-phenylprop-1-ynyl)benzene (2c):
85%. A clear oil. H NMR (CDCl , 400 MHz): d 0.92 (t,
3
1
Yield 83%. A clear oil. H NMR (CDCl
3
, 400 MHz): d 3.78
3H, J = 7.2 Hz), 1.39–1.48 (m, 2H), 1.50–1.58 (m, 2H), 2.27
(
s, 3H), 5.16 (s, 1H), 6.85 (d, 2H, J = 8.8 Hz), 7.19–7.48 (m,
(td, 2H, J = 7.2 Hz and 2.3 Hz), 3.76 (s, 3H), 4.92 (s, 1H),
6.80–6.84 (m, 2H), 7.16–7.36 (m, 7H) ppm; C NMR
13
13
1
9
1
3
1
2H) ppm; C NMR (CDCl , 100 MHz): d 43.1, 55.4, 84.6,
3
0.4, 113.7, 123.2, 126.4, 127.4, 127.5, 127.8, 128.2, 128.5,
(CDCl , 100 MHz): d 13.7, 18.7, 22.1, 31.1, 42.5, 55.3, 80.8,
3
31.2, 133.5, 141.5, 157.8 ppm; IR (film) mmax: 3060, 3029,
85.0, 113.9, 126.6, 127.8, 128.5, 128.8, 134.8, 142.8,
À1
À1
002, 1608, 1584, 1509, 1251 cm
-(3-(2,4-Dimethoxyphenyl)-3-phenylprop-1-ynyl)benzene
.
158.3 ppm; IR (film) mmax: 1600, 1509, 1452, 1248 cm
.
Anal. Calcd for C H O: C, 86.29; H, 7.97. Found: C,
20 22
1
(
(
6
2
2d): Yield 80%. A white solid (mp 101–102 °C). H NMR
CDCl , 400 MHz): d 3.78 (s, 3H), 3.80 (s, 3H), 5.58 (s, 1H),
.44 (d, 1H, J = 2.4 Hz), 6.49 (dd, 1H, J = 8.4 Hz and
86.15; H, 8.08.
4-(1-Phenylhept-2-ynyl)phenol (2l): Yield 93%. A yellow oil.
3
1
3
H NMR (CDCl , 400 MHz): d 0.92 (t, 3H, J = 7.2 Hz),
1
3
.4 Hz), 7.16–7.31 (m, 6H), 7.43–7.51 (m, 5H) ppm;
, 100 MHz): d 36.1, 55.3, 55.5, 83.4, 91.1,
8.6, 104.5, 122.9, 123.8, 126.4, 127.7, 128.1, 128.3, 129.5,
C
1.38–1.59 (m, 4H), 2.27 (td, 2H, J = 7.2 and 2.0 Hz), 4.66–
NMR (CDCl
3
4.76 (br s, 1H), 4.91 (s, 1H), 6.72–6.77 (m, 2H), 7.16–7.25 (m,
1
3
9
1
3
1
3H), 7.29 (t, 2H, J = 7.6 Hz), 7.32–7.37 (m, 2H); C NMR
31.7, 142.1, 157.1, 159.9 ppm; IR (film) mmax: 3059, 3027,
(CDCl , 100 MHz): d 13.7, 18.7, 22.1, 31.1, 42.5, 80.8, 85.0,
3
À1
001, 2224, 1610, 1588, 1504, 1453, 1264 cm
-(1,3-Diphenylprop-2-ynyl)-2-methoxynaphthalene
.
115.3, 126.6, 127.8, 128.5, 129.1, 135.0, 142.8, 154.2; IR
À1
(2e):
(film) mmax: 3387, 1598, 1510, 1452 cm . Anal. Calcd for
1
Yield 92%. A white solid (mp 110–111 °C). H NMR
C
19
H20O: C, 86.32; H, 7.63. Found: C, 86. 51; H, 7.35.
(
CDCl , 400 MHz): d 3.88 (s, 3H), 6.52 (s, 1H), 7.10–7.29
2-(1-Phenylhept-2-ynyl)furan (2m): Yield 86%. A pale
3
1
(
m, 9H), 7.39–7.43 (m, 2H), 7.48–7.51 (m, 2H), 7.71
3
yellow oil. H NMR (CDCl , 400 MHz): d 0.91 (t, 3H,
(
apparent d, 1H, J = 8.8 Hz), 7.75 (d, 1H, J = 8.8 Hz),
.15 (apparent d, 1H, J = 8.7 Hz) ppm; C NMR (CDCl ,
3
00 MHz): d 32.9, 57.1, 84.3, 90.7, 113.6, 122.1, 123.6,
24.1, 125.7, 126.2, 126.4, 127.3, 128.1, 128.4, 128.5, 128.6,
J = 7.3 Hz), 1.38–1.48 (m, 2H), 1.49–1.57 (m, 2H), 2.26 (td,
2H, J = 6.8 Hz and 2.3 Hz), 5.01 (s, 1H), 6.18 (d, 1H,
J = 3.2 Hz), 6.27 (dd, 1H, J = 3.2 Hz and 1.8 Hz), 7.21–7.42
(m, 6H) ppm; C NMR (CDCl , 100 MHz): d 13.6, 18.5,
3
22.0, 30.9, 37.3, 77.8, 84.3, 106.2, 110.2, 127.1, 127.7, 128.5,
1
3
8
1
1
1
3
2
1
3
29.9, 130.2, 131.9, 132.2, 141.1, 154.3 ppm; IR (film) mmax
:
À1
059, 3029, 1623, 1596, 1512, 1490, 1250 cm
.
139.5, 142.0, 154.6 ppm; IR (film) mmax: 3063, 3029, 1599,
À1
-(1,3-Diphenylprop-2-ynyl)furan (2f): Yield 81%. A yellow
1502, 1453, 1073 cm . Anal. Calcd for C H O: C, 85.67;
1
7
18
1
oil. H NMR (CDCl
3
, 400 MHz): d 5.26 (s, 1H), 6.28
H, 7.61. Found: C, 85.75; H, 7.42.
(
(
apparent d, 1H, J = 3.0 Hz), 6.30–6.33 (m, 1H), 7.23–7.39
m, 7H), 7.45–7.51 (m, 4H) ppm; C NMR (CDCl3,
1-(1-Phenylprop-2-ynyl)naphthalen-2-ol (2n): Yield 68%. A
1
3
1
colorless oil. H NMR (CDCl , 400 MHz): d 2.60 (d, 1H,
3
100 MHz): d 37.8, 83.9, 87.4, 106.6, 110.3, 123.1, 127.3,
J = 3.9 Hz), 6.08 (s, 1H), 6.14 (d, 1H, J = 3.9 Hz), 7.13 (d,
1
27.8, 128.1, 128.2, 128.6, 131.7, 138.8, 142.2, 153.7 ppm;
1H, J = 8.8 Hz), 7.18–7.45 (m, 7H), 7.74 (d, 1H, J = 8.8 Hz),
1
3
IR (film) mmax: 3117, 3061, 3030, 1598, 1501, 1491, 1453,
1
7.78 (d, 1H, J = 8.0 Hz), 7.94 (d, 1H, J = 8.6 Hz) ppm;
C
À1
071 cm
.
NMR (CDCl , 100 MHz): d 32.9, 73.9, 83.4, 117.3, 119.1,
3
2
-(1,3-Diphenylprop-2-ynyl)-1H-pyrrole (2g): Yield 60%. A
123.1, 123.4, 126.9, 127.1, 128.7, 128.9, 129.7, 130.0, 132.3,
1
brown solid (mp 68–71 °C). H NMR (CDCl
5
2
3
, 400 MHz): d
.28 (s, 1H), 6.02–6.06 (m, 1H), 6.15 (dd, 1H, J = 6.0 and
.8 Hz), 6.68–6.71 (m, 1H), 7.23–7.37 (m, 6H), 7.42–7.49
138.9, 152.1 ppm; IR (film) mmax: 3455, 3284, 3058, 3027,
À1
2112, 1630, 1599, 1520, 1490 cm . Anal. Calcd for
C H O: C, 88.34; H, 5.46. Found: C, 88.51; H, 5.40.
1
9
14
1
3
(
m, 4H), 8.16 (br s, 1H) ppm;
C NMR (CDCl
3
,
2-(1-Phenylprop-2-ynyl)furan (2o): Yield 55%. A pale yellow
1
100 MHz): d 37.3, 84.2, 88.6, 106.6, 108.7, 117.4, 123.2,
3
oil. H NMR (CDCl , 400 MHz): d 2.44 (d, 1H, J = 2.5 Hz),
1
27.3, 127.8, 128.2, 128.3, 128.8, 130.6, 131.8, 140.2 ppm;
5.06 (d, 1H, J = 2.5 Hz), 6.21–6.24 (m, 1H), 6.29–6.32 (m,
À1
13
IR (film) mmax: 3431, 1597, 1489, 1452 cm
.
3-(4-Methoxyphenyl)-3-phenylprop-1-ynyl)trimethylsilane
1H), 7.24–7.44 (m, 6H) ppm; C NMR (CDCl , 100 MHz):
3
(
d 37.0, 72.0, 81.9, 106.7, 110.3, 127.5, 127.7, 128.6, 138.2,
1
(2h): Yield 80%. A clear oil. H NMR (CDCl
3
, 400 MHz): d
142.3, 153.1 ppm; IR (film) mmax: 3293, 3063, 3030, 2122,
À1
0
.27 (s, 9H), 3.82 (s, 3H), 5.05 (s, 1H), 6.90 (d, 2H,
1599, 1503, 1453 cm
.
1-(2-Methyl-4-phenylbut-3-yn-2-yl)naphthalen-2-ol
1
3
J = 8.1 Hz), 7.26–7.45 (m, 7H) ppm; C NMR (CDCl
3
,
(2p):
1
1
1
3
(
00 MHz): d 0.2, 43.3, 55.3, 88.9, 107.1, 114.0, 126.8, 127.8,
28.6, 128.9, 133.8, 141.9, 158.5 ppm; IR (film) mmax: 3062,
028, 2171, 1603, 1510, 1453, 1249, 840 cm
3-(2,4-Dimethoxyphenyl)-3-phenylprop-1-ynyl)trimethyl-
Yield 91%.
A
pale yellow oil.
H
NMR (CDCl ,
3
400 MHz): d 1.39 (s, 6H), 5.59 (s, 1H), 6.88–7.19 (m, 9H),
À1
13
.
7.59 (d, 2H, J = 8.8 Hz) ppm; C NMR (CDCl , 100 MHz):
3
d 26.3, 75.3, 116.0, 118.8, 122.9, 125.0, 126.3, 127.2, 127.8,
1
silane (2i): Yield 78%. A colorless solid (mp 82–84 °C). H
NMR (CDCl , 400 MHz): d 0.19 (s, 9H), 3.77 (s, 3H), 3.78
128.3, 129.8, 130.1, 130.3, 130.4, 135.4, 141.6, 153.0 ppm; IR
À1
(film) mmax: 3473, 3054, 2248, 1623, 1590, 1505, 1453 cm
.
3