TBuOLi-mediated alkynylation of aldehydes

Article abstract of DOI:10.1080/00397911.2010.481740

The lithium tert-butoxide reagent was found to promote the addition of terminal aromatic alkynes to various aromatic aldehydes. This reaction was efficiently carried out in anhydrous dimethylformamide at room temperature in air for 50min, and the correspo

Full text of DOI:10.1080/00397911.2010.481740

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tBuOLi-Mediated Alkynylation of
Aldehydes
Chuanbin Li a , Xiaolong Li a , Xu Meng a , Tiansheng Wang a , Jihui Li
a & Baohua Chen a
a State Key Laboratory of Applied Organic Chemistry, Lanzhou
University, Lanzhou, China
Version of record first published: 21 Mar 2011.
To cite this article: Chuanbin Li , Xiaolong Li , Xu Meng , Tiansheng Wang , Jihui Li & Baohua Chen
(2011): tBuOLi-Mediated Alkynylation of Aldehydes, Synthetic Communications: An International
Journal for Rapid Communication of Synthetic Organic Chemistry, 41:8, 1208-1217
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Synthetic Communications1, 41: 1208–1217, 2011
Copyright # Taylor & Francis Group, LLC
ISSN: 0039-7911 print=1532-2432 online
DOI: 10.1080/00397911.2010.481740
tBuOLi-MEDIATED ALKYNYLATION OF ALDEHYDES
Chuanbin Li, Xiaolong Li, Xu Meng, Tiansheng Wang,
Jihui Li, and Baohua Chen
State Key Laboratory of Applied Organic Chemistry, Lanzhou University,
Lanzhou, China
GRAPHICAL ABSTRACT
Abstract The lithium tert-butoxide reagent was found to promote the addition of terminal
aromatic alkynes to various aromatic aldehydes. This reaction was efficiently carried out in
anhydrous dimethylformamide at room temperature in air for 50 min, and the corresponding
propargylic alcohols were obtained in good to excellent yields (up to 95%).
Keywords Alkynylation; lithium tert-butoxide; propargylic alcohol
The alkynylation of carbonyl compounds is one of the most useful carbon–carbon
bond-forming reactions[1] and asymmetric carbon–carbon bond-forming reactions.[2]
The corresponding propargylic alcohols are important and versatile building blocks
for fine chemicals, pharmaceuticals, and natural products.[3] One of the most com-
mon methods to create this type of bond is the nucleophilic addition of alkynylme-
tals containing Ce,[4] B,[5] V,[6] and Al[7] to carbonyl compounds. Another practical
manner is the combined use of Lewis acids, such as Sn(OTf)2,[8] GaI3,[9]
Zn(OTf)2,[10a] ZnCl2,[10b] and InBr3,[11] and Lewis bases, such as amine, in the syn-
thesis of propargylic alcohols. Apart from these methods, stoichiometric amounts
of dialkylzinc reagents are also widely used for synthsis of propargylic alcohols with
or without Lewis acid.[12] Although many significant results have been achieved in
this area, the importance of these compounds in academic research and industrial
applications provides the constant driving force for the development of this reaction.
t
Herein, we report a successful alkynylation of aldehydes using BuOLi as a
base, leading to the corresponding propargylic alcohols in execellent yield under mild
conditions (Scheme 1).
Received May 14, 2009.
Address correspondence to Baohua Chen, State Key Laboratory of Applied Organic Chemistry,
Lanzhou University, Lanzhou 730000, China. E-mail: chbh@lzu.edu.cn
1208

tBuOLi-MEDIATED ALKYNYLATION OF ALDEHYDES
1209
Scheme 1. Alkynylation of aldehydes.
Our initial study began with the reaction of benzaldehyde (0.2 mmol), 2.0 equiv
of tBuOLi, and 1.2 equiv of phenylacetylene in anhydrous tetrahydrofuran (THF) at
room temperature under air for 50 min. The desired product 1,3-diphenylprop-2-yn-
1-ol was isolated in 83% yield (Table 1, entry 1). LiOMe, LiOEt, LiCl, Li2CO3, and
LiClO4 were also investigated. LiOMe and LiOEt provided poor yields (Table 1,
entries 2 and 3); the others did not promote the reaction at all (Table 1, entries
Table 1. Optimization of reaction conditionsa
Entry
Base
Base (equiv)
Solvent
Yield (%)b
1
2
tBuOLi
LiOMe
LiOEt
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
3.0
1.5
1.0
THF
THF
THF
83
Trace
5
NDc
NDc
NDc
40
3
4
LiCl
THF
THF
5
Li2CO3
LiClO4
tBuOLi
tBuOLi
tBuOLi
tBuOLi
tBuOLi
tBuOLi
tBuOLi
tBuOLi
tBuOLi
tBuOLi
tBuOLi
tBuOLi
tBuOLi
tBuOLi
tBuOLi
tBuOLi
6
THF
DCE
7
8
1,4-Dioxane
DMSO
CH3CN
PhCH3
CH2Cl2
CH3OH
DMFd
CHCl3
NMP
Trace
20
72
9
10
11
12
13
14
15
16
17
18
19
20
21
22
50
78
Trace
82
Trace
Trace
24
Hexane
Acetone
DMF
84
89
DMF
DMF
DMF
85
76
63
aAll reactions were carried out in anhydrous solvent at room temperature in air for 50 min.
bIsolated yields based on the benzaldehyde.
cND, not detected.
dCommercial DMF.

1210
C. LI ET AL.
4–6). Then the reaction was carried out using several different solvents (Table 1,
entries 7–18), and anhydrous dimethylformamide (DMF) was the best solvent. To
obtain the optimized reaction condition, we changed the amount of tBuOLi
(Table 1, entries 19–22). The results are summarized in Table 1. Consequently, we
found that the yield of the product was improved to 89% when the mixture of 1.0
t
equiv of benzaldehyde, 2.0 equiv of BuOLi, and 1.2 equiv of phenylacetylene was
conducted in anhydrous DMF at room temperature under air for 50 min.
To extend the general applicability of this alkynylation of aldehydes, the reac-
tion of terminal aromatic alkynes with various aromatic aldehydes under the opti-
mized conditions was investigated. The results are summarized in Table 2.
The reactivity of different aromatic aldehydes was influenced by the nature and
position of the substitutents on the aromatic ring. The benzaldehyde derivatives
Table 2. Alkynylation of aldehydea
Entry
Aldehyde
Alkyne
Yield (%)b
1
2
Benzaldehyde
Phenylacetylene
Phenylacetylene
89
90
4-Chlorobenzaldehyde
2-Bromobenzaldehyde
2-Chlorobenzaldehyde
3-Chlorobenzaldehyde
2,4-Dichloro-benzaldehyde
2-Methoxy-benzaldehyde
4-Methoxy-benzaldehyde
Benzo(d) (1,3)dioxole-4-carbaldehyde
3,4-Dimethyl-benzaldehyde
4-Methylbenzaldehyde
Ferrocenylaldehyde
3
Phenylacetylene
Phenylacetylene
94
94
4
5
Phenylacetylene
Phenylacetylene
trace
88
6
7
Phenylacetylene
Phenylacetylene
87
84
8
9
Phenylacetylene
Phenylacetylene
80
83
10
11
12
13
14
15
16
17
18
19
20
21
22
23
Phenylacetylene
Phenylacetylene
79
80
4-Ferrocenyl-benzaldehyde
4-Nitrobenzaldehyde
4-Hydroxy-benzaldehyde
2-Furaldehyde
Phenylacetylene
Phenylacetylene
Phenylacetylene
66
NDc
NDc
68
4-Fluoro phenylacetylene
4-Fluoro phenylacetylene
4-Methoxy phenylacetylene
2-Chloro phenylacetylene
m-tolyl Phenylacetylene
Naphthyl acetylene
2-Pyridylacetylene
3-Thiophenyl acetylene
Benzaldehyde
Benzaldehyde
87
89
2-Bromobenzaldehyde
4-Chlorobenzaldehyde
2-Bromobenzaldehyde
Benzaldehyde
92
76
95
95
2-Chlorobenzaldehyde
92
t
aAll reactions were carried out using 1.0 equiv of benzaldehyde, 2.0 equiv of BuOLi, 1.2 equiv of
phenylacetylene, and 1.5 ml of DMF at room temperature for 50 min.
bIsolated yield based on the aldehyde.
cND, not detected.

tBuOLi-MEDIATED ALKYNYLATION OF ALDEHYDES
1211
having an electron-withdrawing or electron-donating substituent on the o-=p-
position of the aromatic ring were highly reactive and gave the products in excellent
yields (Table 2, entries 2–4, 6–11). The m-position electron-withdrawing substituent
did not give the expected product (Table 2, entry 3). Under similar conditions,
4-nitrobenzaldehyde and 4-hydroxybenzaldehyde produced a small amount of the
corresponding alcohols (Table 2, entries 14 and 15). Otherwise, 4-ferrocenyl-
benzaldehyde, ferrocenylaldehyde, and 2-furaldehyde also gave satisfactory yields
(Table 2, entries 11, 12, and 16). Similarly, the reaction of aromatic alkynes contain-
ing different groups has also been investigated. 2-Chlorophenylacetylene and 2-bro-
mobenzaldehyde result in 95% yield (Table 2, entry 19). m-Tolylphenylacetylene and
4-chlorobenzaldehyde gave 76% yield (Table 2, entry 18). 4-Furalphenylacetylene
and 4-methoxyphenylacetylene (Table 2, entries 16 and 17) were good terminal
alkyne components in this reaction (89%). It should be noted that the heterocyclic
aromatic alkynes and 2-naphthalethyne were also good substrates for this reaction
(Table 2, entries 21–23).
In summary, we have described a simple and efficient method for preparation
of propargylic alcohols. The process showed considerable advantages in terms of
mild reaction, short reaction time, simplicity of the reaction procedure, easily avail-
able reagents, and good to excellent yields.
REPRESENTATIVE PRODUCTS
1,3-Diphenylprop-2-yn-1-ol[13]: General Procedure for Alkynylation
of Aldehydes
tBuOLi (0.4 mmol), benzaldehyde (0.2 mmol), and phenylacetylene (0.24 mmol)
were added to a 10-ml flask equipped with a magnetic stirring bar. Then DMF
(1.5 ml) was added to the flask by a syringe. Finally, the reaction mixture was stirred
for 50 min at room temperature in air. When the reaction was completed thin-layer
chromatography, (TLC), the mixture was extracted with ethyl acetate (3 ꢀ 5 ml), and
the combined organic layer was washed with water and brine, dried over MgSO4,
filtered, and concentrated under vacuum. The residue was purified by column chro-
matography [silica gel (200–300 mesh)] to give product 1,3-diphenylprop-2-yn-1-ol in
89% yield.
1
Colorless oil. H NMR (300 MHz, CDCl3): d ¼ 2.43 (s, 1H), d ¼ 5.68 (s, 1H),
d ¼ 7.30–7.33 (m, 4H), d ¼ 7.36–7.42 (m, 2H), d ¼ 7.45–7.48 (m, 2H), d ¼ 7.60 (d,
J ¼ 7.5 Hz, 2H). 13C NMR (75 MHz, CDCl3): d ¼ 65.1, 86.6, 88.7, 122.4, 126.7,
128.3, 128.4, 128.6, 128.6, 131.7, 140.6. MS (FAB): m=z (%) ¼ 208 [Mþ]. Anal. calcd.
for C15H12O: C, 86.51; H, 5.81. Found: C, 86.75; H, 5.79.
1-(4-Chlorophenyl)-3-phenylprop-2-yn-1-ol[14]
1
Colorless oil. H NMR (300 MHz, CDCl3): d ¼ 2.48 (s, 1H), d ¼ 5.65 (s, 1H),
d ¼ 7.25–7.34 (m, 4H), d ¼ 7.37 (s, 1H), d ¼ 7.44–7.47 (m, 2H), d ¼ 7.52 (s, 1H),
d ¼ 7.55 (s, 1H). 13C NMR (75 MHz, CDCl3): d ¼ 64.3, 86.8, 88.1, 122.0, 128.0,
128.3, 128.4, 128.7, 131.6, 134.1, 139.0. MS (FAB): m=z (%) ¼ 242 [Mþ]. Anal. calcd.
for C15H11ClO: C, 74.23; H, 4.57. Found: C, 74.32; H, 4.62.

1212
C. LI ET AL.
1-(2-Bromophenyl)-3-phenylprop-2-yn-1-ol[14]
1
Colorless oil. H NMR (300 MHz, CDCl3): d ¼ 2.79 (s, 1H), d ¼ 6.00 (s, 1H),
d ¼ 7.15–7.23 (m, 1H), d ¼ 7.26–7.38 (m, 4H), d ¼ 7.44–7.48 (m, 2H), d ¼ 7.55–7.58
(d, J ¼ 8.1 Hz, 1H), d ¼ 7.81–7.84 (dd, J ¼ 1.5, 7.8 Hz, 1H). 13C NMR (75 MHz,
CDCl3): d ¼ 64.6, 86.7, 87.6, 122.2, 122.7, 127.8, 128.2, 128.6, 129.9, 131.7, 133.0,
139.4. MS (FAB): m=z (%) ¼ 286 [Mþ]. Anal. calcd. for C15H11BrO: C, 62.74; H,
3.86. Found: C, 62.91; H, 3.80.
1-(2-Chlorophenyl)-3-phenylprop-2-yn-1-ol[14]
1
Colorless oil. H NMR (300 MHz, CDCl3): d ¼ 2.75 (s, 1H), d ¼ 6.03 (s, 1H),
d ¼ 7.23–7.34 (m, 5H), d ¼ 7.37–7.40 (dd, J ¼ 2.1, 7.5, 1H), d ¼ 7.44–7.48 (m, 2H),
d ¼ 7.80–7.84 (dd, J ¼ 2.1, 7.5 Hz, 1H). 13C NMR (75 MHz, CDCl3): d ¼ 62.4,
86.6, 87.5, 122.2, 127.2, 128.2, 128.4, 128.6, 129.7, 129.7, 131.7, 132.7, 137.8. MS
(FAB): m=z (%) ¼ 242 [Mþ]. Anal. calcd. for C15H11ClO: C, 74.23; H, 4.57. Found:
C, 74.44; H, 4.51.
1-(2,4-Dichlorophenyl)-3-phenylprop-2-yn-1-ol
1
Colorless oil. H NMR (300 MHz, CDCl3): d ¼ 2.89 (s, 1H), d ¼ 5.96 (s, 1H),
d ¼ 7.23–7.35 (m, 4H), d ¼ 7.38–7.38 (d, J ¼ 1.8 Hz, 1H), d ¼ 7.42–7.45 (m, 2H),
d ¼ 7.72–7.75 (d, J ¼ 8.1 Hz, 1H). 13C NMR (75 MHz, CDCl3): d ¼ 61.8, 86.8,
87.1, 122.0, 127.5, 128.3, 128.8, 129.2, 129.5, 131.7, 133.4, 134.7, 136.5. MS
(FAB): m=z (%) ¼ 276 [Mþ]. Anal. calcd. for C15H10Cl2O: C, 65.01; H, 3.64. Found:
C, 65.37; H, 3.58.
1-(2-Methoxyphenyl)-3-phenylprop-2-yn-1-ol[15]
1
Yellow oil. H NMR (300 MHz, CDCl3): d ¼ 3.87 (s, 3H), d ¼ 5.93 (s, 1H),
d ¼ 6.90–6.92 (d, J ¼ 8.4 Hz, 1H), d ¼ 6.97–7.01 (m, 1H), d ¼ 7.23–7.34 (m, 4H),
d ¼ 7.45–7.49 (m, 2H), d ¼ 7.63–7.66 (dd, J ¼ 1.5, 8.2 Hz, 1H). 13C NMR (75 MHz,
CDCl3): d ¼ 55.5, 61.5, 86.0, 88.3, 110.8, 120.8, 122.7, 127.9, 128.2, 128.3, 128.7,
129.7, 131.7, 156.7. MS (FAB): m=z (%) ¼ 238 [Mþ]. Anal. calcd. for C16H14O2:
C, 80.65; H, 5.92. Found: C, 80.81; H, 5.88.
1-(4-Methoxyphenyl)-3-phenylprop-2-yn-1-ol[13]
1
Yellow oil. H NMR (300 MHz, CDCl3): d ¼ 2.51 (s, 1H), d ¼ 3.72 (s, 3H),
d ¼ 5.62 (s, 1H), d ¼ 6.89–6.92 (d, J ¼ 8.1 Hz, 2H), d ¼ 7.24–7.31 (m, 3H), d ¼ 7.44–
7.48 (m, 2H), d ¼ 7.51–7.54 (m, 2H). 13C NMR (75 MHz, CDCl3): d ¼ 55.3, 64.6,
86.4, 88.9, 113.9, 122.4, 128.1, 128.2, 128.5, 131.7, 132.9, 159.6. MS (FAB): m=z
(%) ¼ 238 [Mþ]. Anal. calcd. for C16H14O2: C, 80.65; H, 5.92. Found: C, 80.81; H, 5.88.
1-(Benzo(d)(1,3)dioxol-5-yl)-3-phenylprop-2-yn-1-ol[16]
1
Yellow oil. H NMR (300 MHz, CDCl3): d ¼ 2.62 (s, 1H), d ¼ 5.57 (s, 1H),
d ¼ 5.92 (s, 2H), d ¼ 6.77–6.80 (d, J ¼ 7.8 Hz, 1H), d ¼ 7.03–7.06 (dd, J ¼ 1.5,

tBuOLi-MEDIATED ALKYNYLATION OF ALDEHYDES
1213
7.8 Hz, 1H), d ¼ 7.10–7.10 (d, J ¼ 1.5 Hz, 1H), d ¼ 7.24–7.33 (m, 3H), d ¼ 7.42–7.47
(m, 2H). 13C NMR (75 MHz, CDCl3): d ¼ 64.8, 86.4, 88.6, 101.1, 107.4, 108.1,
120.4, 122.3, 128.2, 128.5, 131.7, 134.7, 147.6, 147.8. MS (FAB): m=z (%) ¼ 252
[Mþ]. Anal. calcd. for C16H12O3: C, 76.18; H, 4.79. Found: C, 76.42; H, 4.73.
1-(3,4-Dimethylphenyl)-3-phenylprop-2-yn-1-ol
1
Colorless oil. H NMR (400 MHz, CDCl3): d ¼ 2.26 (s, 3H), d ¼ 2.28 (s, 3H),
d ¼ 2.36 (s, 1H), d ¼ 5.62 (s, 1H), d ¼ 7.14–7.16 (d, J ¼ 7.6 Hz, 1H), d ¼ 7.29–7.32
(m, 4H), d ¼ 7.36 (s, 1H), d ¼ 7.45–7.47 (dd, J ¼ 3.6, 7.6 Hz, 2H). 13C NMR
(100 MHz, CDCl3): d ¼ 19.5, 19.8, 65.0, 86.3, 89.0, 122.5, 124.1, 128.0, 128.2,
128.5, 129.9, 131.7, 136.9, 138.2. MS (FAB): m=z (%) ¼ 236 [Mþ]. Anal. calcd. for
C17H16O: C, 86.40; H, 6.82. Found: C, 86.63; H, 6.79.
3-Phenyl-1-p-tolyprop-2-yn-1-ol[13]
1
Colorless oil. H NMR (400 MHz, CDCl3): d ¼ 2.35 (s, 3H), d ¼ 2.45 (s, 1H),
d ¼ 5.63 (s, 1H), d ¼ 7.18–7.20 (d, J ¼ 8.0 MHz, 2H), d ¼ 7.28–7.30 (m, 3H),
d ¼ 7.44–7.49 (m, 4H). 13C NMR (100 MHz, CDCl3): d ¼ 21.1, 64.9, 86.4, 88.9,
122.5, 126.7, 128.2, 128.5, 129.3, 131.7, 137.8, 138.2. MS (FAB): m=z (%) ¼ 222
[Mþ]. Anal. calcd. for C16H14O: C, 86.45; H, 6.35. Found: C, 86.71; H, 6.31.
1-Ferrocenyl-3-phenylprop-2-yn-1-ol
Red oil. 1H NMR (400 MHz, CDCl3): d ¼ 2.40 (s, 1H), d ¼ 4.21 (s, 2H),
d ¼ 4.25 (s, 5H), d ¼ 4.40 (s, 1H), d ¼ 4.46 (s, 1H), d ¼ 5.39 (s, 1H), d ¼ 7.34–7.35
(m, 3H), d ¼ 7.50–7.53 (m, 2H). 13C NMR (100 MHz, CDCl3): d ¼ 60.4, 61.4, 66.6,
68.3, 68.4, 68.5, 68.8, 84.5, 89.2, 122.7, 128.3, 128.4, 131.6. MS (FAB): m=z
(%) ¼ 316 [Mþ]. Anal. calcd. for C19H16FeO: C, 72.18; H, 5.10. Found: C, 72.33;
H, 5.13.
1-(4-Ferrocenylphenyl)-3-phenylprop-2-yn-1-ol
Red oil. 1H NMR (300 MHz, CDCl3): d ¼ 4.02 (s, 5H), d ¼ 4.30 (s, 2H),
d ¼ 4.63 (s, 2H), d ¼ 5.65 (s, 1H), d ¼ 7.30–7.32 (m, 3H), d ¼ 7.47–7.53 (m, 6H).
13C NMR (75 MHz, CDCl3): d ¼ 64.9, 66.5, 69.0, 69.6, 84.7, 86.5, 88.7, 122.4,
126.2, 126.8, 128.2, 128.5, 131.7, 137.9, 139.6. MS (FAB): m=z (%) ¼ 392 [Mþ]. Anal.
calcd. for C25H20FeO: C, 76.55; H, 5.14. Found: C, 76.80; H, 5.11.
3-(4-Fluorophenyl)-1-(furan-2-yl)prop-2-yn-1-ol
1
Colorless oil. H NMR (400 MHz, CDCl3): d ¼ 2.49 (s, 1H), d ¼ 5.68 (s, 1H),
d ¼ 6.37–6.39 (m, 1H), d ¼ 6.51–6.52 (d, J ¼ 3.2 Hz, 1H), d ¼ 7.00–7.05 (m, 2H),
d ¼ 7.44–7.49 (m, 3H). 13C NMR (100 MHz, CDCl3): d ¼ 58.6, 84.7, 85.9, 107.9,
110.4, 115.5, 115.8, 118.1, 118.2, 133.7, 133.8, 143.1, 152.8, 161.5, 164.0. MS
(FAB): m=z (%) ¼ 216 [Mþ]. Anal. calcd. for C13H9FO2: C, 72.22; H, 4.20. Found:
C, 72.47; H, 4.22.

1214
C. LI ET AL.
3-(4-Fluorophenyl)-1-phenylprop-2-yn-1-ol[17]
1
Colorless oil. H NMR (400 MHz, CDCl3): d ¼ 2.42 (s,1H), d ¼ 5.67 (s, 1H),
d ¼ 6.98–7.02 (m, 2H), d ¼ 7.326–7.068 (m, 5H), d ¼ 7.59–7.61 (d, J ¼ 7.2, 2H). 13C
NMR (100 MHz, CDCl3): d ¼ 65.1, 85.6, 88.4, 115.5, 115.7, 118.4, 118.5, 126.7,
128.5, 128.7, 133.6, 133.7, 140.6, 161.4, 163.9. MS (FAB): m=z (%) ¼ 226 [Mþ]. Anal.
calcd. for C15H11FO: C, 79.63; H, 4.90. Found: C, 79.88; H, 4.87.
3-(4-Methoxyphenyl)-1-phenylprop-2-yn-1-ol[13]
1
Colorless oil. H NMR (400 MHz, CDCl3): d ¼ 2.03 (s, 1H), d ¼ 3.80 (s, 3H),
d ¼ 5.67 (s, 1H), d ¼ 6.82–6.84 (d, J ¼ 8.4 Hz, 2H), d ¼ 7.34–7.41 (m, 5H), d ¼ 7.60–
7.62 (d, J ¼ 7.6 Hz, 2H). 13C NMR (100 MHz, CDCl3): d ¼ 55.2, 65.1, 86.6, 87.3,
113.9, 114.4, 126.7, 128.3, 128.6, 133.2, 140.8, 159.7. MS (FAB): m=z (%) ¼ 238
[Mþ]. Anal. calcd. for C16H14O2: C, 80.65; H, 5.92. Found: C, 80.90; H, 5.89.
1-(2-Bromophenyl)-3-(2-chlorophenyl)prop-2-yn-1-ol
1
Colorless oil. H NMR (300 MHz, CDCl3): d ¼ 2.71 (s, 1H), d ¼ 6.06 (s, 1H),
d ¼ 7.17–7.29 (m, 3H), d ¼ 7.36–7.41 (m, 2H), d ¼ 7.46–7.52 (dd, J ¼ 2.1, 7.5 Hz,
1H), d ¼ 7.57–7.60 (m, 1H), d ¼ 7.90–7.94 (dd, J ¼ 1.8, 7.8 Hz, 1H). 13C NMR
(75 MHz, CDCl3): d ¼ 64.7, 83.6, 92.7, 122.2, 122.9, 126.4, 127.9, 128.9, 129.2,
129.7, 130.1, 133.0, 133.5, 136.1, 139.1. MS (FAB): m=z (%) ¼ 320 [Mþ]. Anal. calcd.
for C15H10BrClO: C, 56.02; H, 3.13. Found: C, 56.28; H, 3.16.
1-(4-Chlorophenyl)-3-m-tolylprop-2-yn-1-ol
1
Colorless oil. H NMR (400 MHz, CDCl3): d ¼ 2.33 (s, 4H), d ¼ 5.66 (s, 1H),
d ¼ 7.14 (d, J ¼ 7.2 Hz, 1H), d ¼ 7.19 (t, J ¼ 7.2 Hz, 1H), d ¼ 7.25 (d, J ¼ 13.8 Hz,
2H), d ¼ 7.36 (m, 2H), d ¼ 7.54 (d, J ¼ 8.4 Hz, 2H). 13C NMR (100 MHz, CDCl3):
d ¼ 21.2, 64.4, 87.2, 87.9, 122.0, 128.1, 128.3, 128.7, 128.8, 129.7, 132.3, 134.2,
134.4, 138.1, 139.2. MS (FAB): m=z (%) ¼ 256 [Mþ]. Anal. calcd. for C16H13ClO:
C, 74.85; H, 5.10. Found: C, 75.12; H, 5.04.
1-(2-Bromophenyl)-3-(naphthalene-1-yl)prop-2-yn-1-ol
1
Colorless oil. H NMR (300 MHz, CDCl3): d ¼ 2.77 (s, 1H), d ¼ 6.16 (s, 1H),
d ¼ 7.18–7.24 (m, 1H), d ¼ 7.36–7.43 (m, 2H), d ¼ 7.47–7.52 (m, 4H), d ¼ 7.68–7.71
(d, J ¼ 7.5 Hz, 1H), d ¼ 7.81–7.84 (m, 2H), d ¼ 7.90–7.94 (d, J ¼ 1.5 Hz, d, J ¼ 8.1 Hz,
1H), d ¼ 8.29–8.32 (d, J ¼ 8.4 Hz, 1H). 13C NMR (75 MHz, CDCl3): d ¼ 64.9, 84.9,
92.5, 119.8, 122.7, 125.1, 126.0, 126.4, 126.9, 128.0, 128.3, 128.6, 129.1, 130.0,
130.8, 133.0, 133.1, 133.2, 139.6. MS (FAB): m=z (%) ¼ 336 [Mþ]. Anal. calcd. for
C19H13BrO: C, 67.67; H, 3.89. Found: C, 67.88; H, 3.84.
1-Phenyl-3-(pyridine-3-yl)prop-2-yn-1-ol[18]
1
Colorless oil. H NMR (400 MHz, CDCl3): d ¼ 2.44 (s, 1H), d ¼ 5.67 (s, 1H),
d ¼ 7.12–7.14 (d, J ¼ 7.9 Hz, 1H), d ¼ 7.17–7.23 (q, J ¼ 8.0 Hz, 1H), d ¼ 7.26–7.29

tBuOLi-MEDIATED ALKYNYLATION OF ALDEHYDES
1215
(m, 2H), d ¼ 7.33–7.35 (m, 1H), d ¼ 7.37–7.41 (m, 2H), d ¼ 7.60–7.62 (d, J ¼ 7.2 Hz,
2H). 13C NMR (100 MHz, CDCl3): d ¼ 65.1, 86.9, 88.4, 122.2, 126.8, 128.3, 128.7,
128.8, 129.5, 132.4, 138.0, 140.7. MS (FAB): m=z (%) ¼ 209 [Mþ]. Anal. calcd. for
C14H11NO: C, 80.36; H, 5.30. Found: C, 80.61; H, 5.33.
1-(2-Chlorophenyl)-3-(thiophen-3-yl)prop-2-yn-1-ol
1
Colorless oil. H NMR (300 MHz, CDCl3): d ¼ 2.78 (s, 1H), d ¼ 6.01 (s, 1H),
d ¼ 7.10–7.12 (m, 1H), d ¼ 7.23–7.34 (m, 3H), d ¼ 7.36–7.39 (m, 1H), d ¼ 7.46–7.47
(m, 1H), d ¼ 7.78–7.81 (dd, J ¼ 1.2, 7.2 Hz, 1H). 13C NMR (75 MHz, CDCl3):
d ¼ 62.4, 81.9, 87.3, 121.3, 125.4, 127.3, 128.5, 129.5, 129.7, 129.8, 129.9, 132.8,
137.9. MS (FAB): m=z (%) ¼ 248 [Mþ]. Anal. calcd. for C13H9ClOS: C, 62.78; H,
3.65. Found: C, 63.01; H, 3.61.
ACKNOWLEDGMENTS
The authors are grateful to the project sponsored by the Scientific Research
Foundation for the State Education Ministry (No. 107108) and the National Natural
Science Foundation of China (No. J0730425).
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