A Novel Transformation of Esters to Alkynes with 1-Substituted Benzotriazoles

Article abstract of DOI:10.1021/jo962291t

Reactions of lithio benzotriazol-1-yl derivatives 2, 11, and 25 with aromatic and aliphatic esters 3, 12, and 26 gave α-(benzotriazol-l-yl) ketones 4, 13, and 27, respectively, in high yields. Alternatively, α-(benzotriazol-l-yl) ketones 22 can be accessed by the reaction of α-(benzotriazol-1-yl) esters 20 with Grignard reagents. Condensation of 4, 13, 22, and 27 with (p-toluenesulfonyl)hydrazine provided p-tosylhydrazones 5, 14, 21, and 28. Treatment of hydrazones 5, 21, and 28 with n-butyllithium in diethyl ether resulted in the elimination of the tosyl group, dinitrogen, and benzotriazolyl group to afford the corresponding acetylenes 9, 23, and 29 in good yields. When α-(benzotriazol-l-yl) 1-α-phenoxy hydrazones 14 were treated with methyllithium, n-butyllithium, or phenyllithium, alkynes 18 were obtained, in which phenoxy groups were replaced by the lithium reagents.

Full text of DOI:10.1021/jo962291t

4142
J . Org. Chem. 1997, 62, 4142-4147
A Novel Tr a n sfor m a tion of Ester s to Alk yn es w ith 1-Su bstitu ted
Ben zotr ia zoles
Alan R. Katritzky,* J in Wang, Nazira Karodia, and J ianqing Li
Center for Heterocyclic Compounds, Department of Chemistry, University of Florida,
Gainesville, Florida 32611-7200
Received December 9, 1996X
Reactions of lithio benzotriazol-1-yl derivatives 2, 11, and 25 with aromatic and aliphatic esters 3,
12, and 26 gave R-(benzotriazol-1-yl) ketones 4, 13, and 27, respectively, in high yields.
Alternatively, R-(benzotriazol-1-yl) ketones 22 can be accessed by the reaction of R-(benzotriazol-
1-yl) esters 20 with Grignard reagents. Condensation of 4, 13, 22, and 27 with (p-toluenesulfonyl)-
hydrazine provided p-tosylhydrazones 5, 14, 21, and 28. Treatment of hydrazones 5, 21, and 28
with n-butyllithium in diethyl ether resulted in the elimination of the tosyl group, dinitrogen, and
benzotriazolyl group to afford the corresponding acetylenes 9, 23, and 29 in good yields. When
R-(benzotriazol-1-yl) 1-R-phenoxy hydrazones 14 were treated with methyllithium, n-butyllithium,
or phenyllithium, alkynes 18 were obtained, in which phenoxy groups were replaced by the lithium
reagents.
In tr od u ction
is of significant interest, but few such methods have been
reported. Kowalski and co-workers10 treated esters with
(dibromomethyl)lithium in the presence of tetrameth-
ylpiperidine to generate carbon-carbon triple bonds for
siloxyalkyne derivatives. The most general and efficient
acetylenation of esters was independently reported by
Bartlett11 and Lythgoe,12,13 acylation of sulfonyl carban-
ions by esters led to â-keto sulfones, which were con-
verted to enol phosphates by direct phosphorylation;
reductive elimination of both the phosphate and the
sulfonyl group resulted in the corresponding acetylenes.
However, this method requires the use of (i) 2 equiv of
the metalated sulfone to generate the R-keto sulfone, (ii)
toxic diethyl phosphorochloridate, and (iii) harsh reduc-
tive elimination conditions such as sodium metal in liquid
ammonia or sodium amalgam, which may lead to further
reduction to alkenes.
Alkyne preparations by the combination of two frag-
ments with the formation of a triple bond are of consider-
able interest in organic synthesis.1 However, the devel-
opment of such transformations has received relatively
little attention. In principle, such alkyne formation
involves a nucleophilic species and an electrophilic spe-
cies.2,3 Among the electrophiles reported, carbonyl-
containing compounds, especially aldehydes and ketones,
are most widely used due to their great availability.
Several efficient methods using this strategy have been
documented: (i) Coupling of Wittig reagents bearing
R-halogen (Cl, Br, or F) with aldehydes followed by base-
assisted elimination is most frequently used in the syn-
thesis of terminal alkynes.3 (ii) Base-promoted reactions
of dialkyl (diazomethyl)phosphonates or (diazomethyl)-
trimethylsilane with aldehydes and aryl ketones lead
directly to the corresponding homologous alkynes;4-6
however, this method is not effective for the conversion
of dialkyl ketones to alkynes. (iii) Double-elimination
reaction of â-acetoxy or â-alkoxy sulfones prepared from
R-sulfonyl carbanions and aldehydes affords the corre-
sponding acetylenes,7,8 but is applicable only when there
are no allylic hydrogens in the vinyl sulfone intermedi-
ates.
We now report a novel and convenient alkyne synthesis
from esters and benzotriazole derivatives via the forma-
tion of R-(benzotriazol-1-yl) ketones, subsequent treat-
ment with (p-toluenesulfonyl)hydrazine, and base-as-
sisted elimination of a tosyl group, dinitrogen, and
benzotriazolyl group (Schemes 1-4).
Resu lts a n d Discu ssion
1-Substituted benzotriazoles 1a -d and 10 were readily
prepared by our previously reported methods.14-16 Treat-
ment of 1-methylbenzotriazole (1a ) with 1 equiv of
n-butyllithium in THF at -78 °C for 2 h followed by
addition of methyl decanoate, dropwise, gave the R-(ben-
zotriazol-1-yl) ketone 4c in a 40% yield along with
unreacted 1a . Rapid addition of the ester to a solution
of R-lithio methylbenzotriazole 2a at -78 °C improved
the yield of the desired product 4c to 88%, and no starting
Other carbonyl-containing compounds including car-
boxylic acids9 and acyl halides3 were less frequently
employed in such alkynations due to handling difficulties.
The transformation of esters, another class of widely
available carbonyl-containing compounds, into alkynes
X Abstract published in Advance ACS Abstracts, April 15, 1997.
(1) Furber, M. In Comprehensive Organic Functional Group Trans-
formations; Katritzky, A. R., Meth-Cohn, O., Rees, C. W., Eds.;
Pergamon Press: New York, 1995; Vol. 1, p 997.
(2) Ben-Efraim, D. A. In The Chemistry of the Carbon-Carbon Triple
Bond; Patai, S. Ed.; J ohn Wiley & Sons: NewYork, 1978; p 755.
(3) Larock, R. C. In Comprehensive Organic Transformations; VCH
Publishers, Inc.: New York, 1989; p 289.
(4) Colvin, E. W.; Hamill, B. J . J . Chem. Soc., Perkin Trans. 1 1977,
869.
(5) Gilbert, J . C.; Weerasooriya, U. J . Org. Chem. 1979, 44, 4997.
(6) Gilbert, J . C.; Weerasooriya, U. J . Org. Chem. 1982, 47, 1837.
(7) Mandai, T.; Yanagi, T.; Araki, K.; Morisaki, Y.; Kawada, M.;
Otera, J . J . Am. Chem. Soc. 1984, 106, 3670.
(8) Otera, J .; Misawa, H.; Sugimoto, K. J . Org. Chem. 1986, 51, 3830.
(9) Kano, S.; Yokomatsu, T.; Shibuya, S. J . Org. Chem. 1978, 43,
4366.
(10) Kowalski, C. J .; Lal, G. S.; Haque, M. S. J . Am. Chem. Soc.
1986, 108, 7127.
(11) Bartlett, P. A.; Green, F. R., III; Rose, E. H. J . Am. Chem. Soc.
1978, 100, 4852.
(12) Lythgoe, B.; Waterhouse, I. Tetrahedron Lett. 1978, 1, 2625.
(13) Lythgoe, B.; Waterhouse, I. J . Chem. Soc., Perkin Trans. 1 1979,
2429.
(14) Katritzky, A. R.; Rachwal, S.; Caster, K. C.; Mahni, F.; Law,
K. W.; Rubio, O. J . Chem. Soc., Perkin Trans. 1 1987, 781.
(15) Katritzky, A. R.; Drewniak-Deyrup, M.; Lan, X.; Brunner, F.
J . Heterocycl. Chem. 1989, 26, 829.
(16) Katritzky, A. R.; Wu, J .; Kuzmierkiewicz, W.; Rachwal, S.
Liebigs Ann. Chem. 1994, 1.
S0022-3263(96)02291-8 CCC: $14.00 © 1997 American Chemical Society

Transformation of Esters to Alkynes with Benzotriazoles
J . Org. Chem., Vol. 62, No. 12, 1997 4143
Ta ble 1. Syn th esis of Acetylen es 9 fr om Ester s 3 a n d 1-Su bstitu ted Ben zotr ia zoles 1 via r-(Ben zotr ia zol-1-yl) Keton es 4
substituents
R2
4
5
6
entry
R1
R3
yield (%)
mp (°C)
yield (%)
mp (°C)
yield (%)
73
75
82
68
85
42
mp (°C)
a
b
c
d
e
f
H
H
H
H
n-C5H11
n-C8H17
n-C9H19
p-CH3-C6H4
Ph
n-C16H33
p-CH3-C6H4
n-C17H35
CH3CH2
CH3CH2
CH3
CH3
CH3
CH3
CH3
CH3
78
83
88
88
98
78
93
81
78-80
87-89
95-96
137-138
171-172
79-80
113-114
82-83
98a
91a
98a
72b
92b
95a
78b
91a
139-141
136-138
140-142
180-181
174-175
128-129
166-167
94-95
oil
oil
oil
oil
59-60
oil
oil
36-38
Ph
1-pyrrolyl
PhS
PhS
g
h
65 (R1 ) H)
58 (R1 ) H)
a
b
Without using Amberlyst-15. In the presence of Amberlyst-15.
wise could be difficult to prepare,17 is also accessible in
moderate yield from the above transformation.
Sch em e 1
In the case of 5g,h , lithiation of these compounds with
6 equiv of n-butyllithium failed to give the desired
product 1-(phenylthio)acetylenes. Instead, terminal
alkynes 9g,h and 1-(phenylthio)butane were obtained.
Presumably, 1-(phenylthio)acetylenes 8 formed first,
which were attacked by n-butyllithium to generate the
products 9g,h and 1-(phenylthio)butane as in an analo-
gous reaction shown by Comasseto and co-workers.18 The
formation of the acetylenes theoretically needs only 2
equiv of n-butyllithium. However, attempts to trap
compound 9g under the same reaction conditions using
2 equiv of n-butyllithium failed, either at room temper-
ature or under reflux, and only starting material was
recovered. When the above reaction was carried out in
toluene under reflux, the starting material decomposed
to give a complex mixture. It was found that 6 equiv of
n-butyllithium gave the best yields (see Note at end).
(Phenoxymethyl)benzotriazole (10) behaved similarly
in the transformations of 10 to ketones 13a -f and
hydrazones 14a -f as illustrated in Scheme 2 and Table
2. Interestingly, the reactions of hydrazones 14a ,b with
6 equiv of n-butyllithium in diethyl ether afforded 1-(p-
methylphenyl)-1-hexyne (18a ) and 5-decyne (18b), re-
spectively, in good yields after column chromatography.
We envisaged that the reaction pathway for the formation
of 18a ,b involved the 1,4-elimination of phenol from
14a ,b to generate intermediate azo-enes 16 which un-
derwent nucleophilic addition with n-butyllithium and
subsequent deprotonation to give dianions 7. Intermedi-
ate 7 decomposed, affording alkynes 18a ,b as shown in
Scheme 2. This reaction mechanism is supported by 1,4-
elimination/addition reaction of R-(halotosyl)hydrazones.19
Similarly, the reaction of hydrazones 14c,d with meth-
yllithium and phenyllithium afforded both aromatic and
aliphatic acetylenes in good yields (Table 2). However,
use of secondary and tertiary butyllithium resulted in
complex mixtures. Nevertheless, the above transforma-
tion of esters and (phenoxymethyl)benzotriazole (10) to
aliphatic acetylenes complemented the present methods
for alkyne synthesis since the alkylation of 1-alkylben-
zotriazoles with carbonyl-containing compounds failed to
give the expected products16 and no aliphatic alkyne could
be obtained by the method of Scheme 1.
material was detected by GCMS. Treatment of the other
substituted benzotriazoles 2b-d with 1 equiv of n-
butyllithium at -78 °C, and subsequent reaction with
an appropriate ester, provided R-(benzotriazol-1-yl) ke-
tones 4a ,b and 4d -h in good to excellent yields (Scheme
1 and Table 1).
Intermediates 4a -c, 4f, and 4h , where R2 was an
aliphatic group, reacted readily with (p-toluenesulfonyl)-
hydrazine in benzene under reflux using a Dean-Stark
trap to give (p-toluenesulfonyl)hydrazones 5a -c, 5f, and
5h , respectively, in good to excellent isolated yields. The
aromatic ketones 4d -e and 4g (where R2 was an
aromatic group) required Amberlyst-15 as a catalyst and
excess (p-toluenesulfonyl)hydrazine for conversion into
the corresponding (p-toluenesulfonyl)hydrazones 5d ,e
and 5g in satisfactory yields as shown in Table 1. All of
the ketones 4a -h and the (p-toluenesulfonyl)hydrazones
5a -h thus prepared were new, and the structures of the
1
products were characterized by H and 13C NMR spec-
Alternatively, R-(benzotriazol-1-yl) ketones 22a -c can
be prepared, in moderate yields, from the reaction of
Grignard reagents with R-(benzotriazol-1-yl) esters 20a ,b
troscopy and elemental analyses.
Treatment of the corresponding (p-toluenesulfonyl)-
hydrazones 5a -f with 6 equiv of n-butyllithium in diethyl
ether at -78 °C under nitrogen for 2 h and then the
solutions were kept at 20 °C for 2 days with stirring,
resulted, after column chromatography, in the formation
of the expected acetylenes 9a -f in generally good yields.
Significantly, the heterocyclic ynamine 9f, which other-
(17) Booker-Milburn, K. I. In Comprehensive Organic Functional
Group Transformations; Katritzky, A. R., Meth-Cohn, O., Rees, C. W.,
Eds.; Pergamon Press: New York, 1995; Vol. 2, p 1039.
(18) Braga, A. L.; Comasseto, J . V.; Petragnani, N. Tetrahedron Lett.
1984, 25, 1111.
(19) Sacks, C. E.; Fuchs, P. L. J . Am. Chem. Soc. 1975, 97, 7372.

4144 J . Org. Chem., Vol. 62, No. 12, 1997
Katritzky et al.
Ta ble 2. Syn th esis of Acetylen es 18 fr om (P h en oxym eth yl)ben zotr ia zoles 10 a n d Ester s 12
substituents
R2
13
14
18
entry
R1
R3
yield (%)
mp (°C)
yield (%)
mp (°C)
yield (%)
mp (°C)
a
b
c
d
e
f
p-CH3-C6H4
n-C4H9
Ph
Ph
n-C7H15
n-C7H15
CH3
CH3CH2
CH3
CH3
CH3CH2
CH3CH2
n-C4H9
n-C4H9
CH3
Ph
Ph
92
75
95
95
88
88
130-131
oil
108-109
108-109
oil
71a
80b
68a
68a
95b
95b
162-163
129-130
138-139
138-139
108-110
108-110
63
72
74
78
83
68
oil
oil
oil
56-58
oil
oil
CH3
oil
a
b
In the presence of Amberlyst-15. Without using Amberlyst-15.
Sch em e 2
Sch em e 4
suberate (26) reacted with 2 equiv of 1-(R-lithiobenzyl)-
benzotriazole (25), generated from the reaction of n-
butyllithium and 1-benzylbenzotriazole (24), to give the
1,10-bis(benzotriazol-1-yl)-1,10-diphenyl-2,9-decanedi-
one (27) which was treated with (p-toluenesulfonyl)-
hydrazine to afford 1,10-bis(benzotriazol-1-yl)-1,10-diphe-
nyl-2,9-decanedione bis(p-tosylhydrazone) (28). The
reaction of tosylhydrazone 28 with 12 equiv of n-butyl-
lithium furnished the expected product 1,10-diphenyl-
1,9-decadiyne (29) (Scheme 4).
Sch em e 3
In summary, we have developed a new, efficient, and
convenient synthetic methodology for the preparation of
various aromatic, aliphatic, and terminal acetylenes from
both aromatic and aliphatic esters.
Exp er im en ta l Section
Gen er a l Com m en ts. Melting points were determined on
a hot stage apparatus without correction. 1H and 13C NMR
spectra were recorded on a 300 MHz spectrometer in CDCl3
or DMSO-d6. Diethyl ether and THF were freshly distilled
from sodium-benzophenone ketyl immediately before use. All
lithiations were carried out in a nitrogen atmosphere.
P r ep a r a tion of r-(Ben zotr ia zol-1-yl) Keton es 4a -h
a n d 13a -f. Gen er a l P r oced u r e. To a stirred solution of
the corresponding 1-substituted benzotriazole 2 (10 mmol)
(Schemes 1 and 2 and Tables 1 and 2) in THF was added
n-butyllithium (4.5 mL, 10 mmol, 2.22 M in hexane) at -78
°C under nitrogen followed by the appropriate ester 3 or 12
(10 mmol) in THF (10 mL). The mixture was stirred for
another 12 h while the temperature was allowed to rise to 20
°C. The reaction was quenched with water, extracted with
ethyl acetate, and dried over anhydrous magnesium sulfate.
Removal of the solvent via rotary evaporation gave a residue
which was subjected to column chromatography or crystal-
lization to provide the desired ketones 4 or 13 (Tables 1 and
2).
derived from R-bromo ketones 19a ,b and benzotriazole
in high yields (Scheme 3).20 Similarly, as in Scheme 1,
compounds 22a -c were converted to hydrazones 21a -c
and alkynes 23a -c in satisfactory yields. Thus, R-(ben-
zotriazol-1-yl) esters 20a ,b can be considered as the
acetylenic cation synthons for the synthesis of various
alkynes.
Analogous transformations can also be applied to the
preparation of bifunctional acetylenes. Thus, diethyl
1-(Ben zotr ia zol-1-yl)-2-h ep ta n on e (4a ): purified by col-
umn chromatography using EtOAc/hexane (1:3) as the eluent;
(20) Katritzky, A. R.; Wu, J . Synthesis 1994, 597.

Transformation of Esters to Alkynes with Benzotriazoles
J . Org. Chem., Vol. 62, No. 12, 1997 4145
1H NMR δ 8.10 (d, J ) 8.2 Hz, 1 H), 7.54-7.49 (m, 1 H), 7.40
(d, J ) 7.8 Hz, 2 H), 5.44 (s, 2 H), 2.48 (t, J ) 7.2 Hz, 2 H),
1.68-1.58 (m, 2 H), 1.37-1.23 (m, 4 H), 0.88 (t, J ) 6.8 Hz, 3
H); 13C NMR δ 202.3, 145.9, 133.4, 127.8, 124.0, 120.1, 109.1,
56.2, 39.7, 31.0, 22.9, 22.2, 13.7. Anal. Calcd for C13H17N3O:
C, 67.51; H, 7.41; N, 18.17. Found: C, 67.61; H, 7.63; N, 18.21.
1-(Ben zotr ia zol-1-yl)-2-d eca n on e (4b): purified by col-
umn chromatography using EtOAc/hexane (1:3) as the eluent;
1H NMR δ 8.06 (d, J ) 8.9 Hz, 1 H), 7.52-7.44 (m, 1 H), 7.42-
7.33 (m, 2 H), 5.42 (s, 2 H), 2.46 (t, J ) 7.3 Hz, 2 H), 1.67-
1.54 (m, 2 H), 1.35-1.17 (m, 10 H), 0.87 (t, J ) 6.7 Hz, 3 H);
13C NMR δ 202.2, 145.9, 133.4, 127.8, 124.0, 120.0, 109.1, 56.2,
39.7, 31.6, 29.1, 29.0, 28.0, 23.1, 22.5, 13.9. Anal. Calcd for
C16H23N3O: C, 70.30; H, 8.48; N, 15.37. Found: C, 70.12; H,
8.64; N, 15.30.
119.9, 116.2, 111.8, 85.4, 21.8. Anal. Calcd for C21H17N3O2:
C, 73.45; H, 4.99; N, 12.24. Found: C, 73.63; H, 4.98; N, 12.27.
1-(Ben zotr ia zol-1-yl)-1-p h en oxyh exa n -2-on e (13b): pu-
rified by column chromatography using EtOAc/hexane (1:3)
as the eluent; 1H NMR δ 8.03 (d, J ) 8.4 Hz, 1 H), 7.62-7.54
(m, 1 H), 7.51-7.40 (m, 1 H), 7.39-7.30 (m, 1 H), 7.28 -7.14
(m, 3 H), 7.12-6.94 (m, 3 H), 3.01-2.88 (m, 1 H), 2.79-2.60
(m, 1 H), 1.78-1.50 (m, 2 H), 1.40-1.20 (m, 2 H), 0.87 (t, J )
6.7 Hz, 3 H); 13C NMR δ 199.9, 156.0, 146.3, 131.7, 129.8,
128.3, 124.5, 123.6, 120.0, 116.2, 110.7, 87.6, 38.4, 25.1, 22.0,
13.6. Anal. Calcd for C18H19N3O2: C, 69.88; H, 6.19; N, 13.58.
Found: C, 69.49; H, 6.34; N, 13.85.
1-(Ben zotr ia zol-1-yl)-1-p h en oxya cetop h en on e (13c )
13d ): purified by recrystallization from EtOAc/hexane (1:4);
1H NMR δ 8.16-8.04 (m, 3 H), 8.02 (d, J ) 8.1 Hz, 1 H), 7.73
(d, J ) 8.3 Hz, 1 H), 7.64-7.53 (m, 1 H), 7.52-7.38 (m, 3 H),
7.37-7.16 (m, 3 H), 7.10 (d, J ) 8.4 Hz, 2 H), 7.02 (t, J ) 7.1
Hz, 1 H); 13C NMR δ 187.6, 155.4, 146.5, 134.5, 133.0, 132.1,
129.9, 129.2, 128.9, 128.3, 124.5, 123.7, 119.9, 116.1, 111.7,
85.3. Anal. Calcd for C20H15N3O2: C, 72.94; H, 4.59; N, 12.76.
Found: C, 72.70; H, 4.61; N, 12.98.
1-(Ben zotr iazol-1-yl)-1-ph en oxy-2-n on an on e (13e ) 13f):
purified by column chromatography using EtOAc/hexane (1:
3) as the eluent; 1H NMR δ 8.05 (d, J ) 9.3 Hz, 1 H), 7.58 (d,
J ) 9.3 Hz, 1 H), 7.48 (t, J ) 8.1 Hz, 1 H), 7.38 (t, J ) 8.1 Hz,
1 H), 7.25 (t, J ) 8.1 Hz, 2 H), 7.15 (s, 1 H), 7.10-7.00 (m, 3
H), 3.01-2.89 (m, 1 H), 2.78-2.62 (m, 1 H), 1.78-1.60 (m, 2
H), 1.40-1.20 (m, 8 H), 0.89 (t, J ) 6.7 Hz, 3 H); 13C NMR δ
199.9, 155.7, 146.4, 131.8, 129.9, 128.3, 124.6, 123.8, 120.2,
116.3, 110.8, 87.7, 38.8, 31.5, 28.9, 28.8, 23.2, 22.5, 14.0. Anal.
Calcd for C21H25N3O2: C, 71.77; H, 7.17; N, 11.96. Found: C,
71.81; H, 7.17; N, 12.23.
P r ep a r a tion of p-Tosylh yd r a zon es 5a -h , 14a -f, a n d
21a -c. Gen er a l P r oced u r e. A mixture of (p-toluenesulfo-
nyl)hydrazine (5 mmol) and the appropriate R-(benzotriazol-
1-yl) ketone 4a , 4c-e, 4h , or 22a -c (5 mmol) in benzene (50
mL) (for the preparation of compound 5d , 5e, 5g, 14a , 14c,d ,
and 21c, a catalytic amount of Amberlyst-15 was needed) was
refluxed, using a Dean-Stark trap, for 12 h. Removal of the
solvent via rotary evaporation gave a residue which was
recrystallized from a mixture of ethyl acetate and hexane to
provide the expected product 5a -h , 14a -f, or 21a -c (Tables
1-3).
1-(Ben zotr ia zol-1-yl)-2-h ep ta n on e p-Tosylh yd r a zon e
(5a ) 21a ): 1H NMR δ 8.35 (s, 1 H), 8.00 (d, J ) 8.4 Hz, 1 H),
7.74 (d, J ) 8.2 Hz, 2 H), 7.37-7.21 (m, 4 H), 7.09 (d, J ) 8.2
Hz, 1 H), 5.32 (s, 2 H), 2.48 (s, 3 H), 2.09-2.03 (m, 2 H), 1.37-
1.22 (m, 2 H), 1.20-1.05 (m, 4 H), 0.75 (t, J ) 6.7 Hz, 3 H);
13C NMR δ 153.1, 146.1, 144.3, 134.9, 133.0, 129.7, 128.0,
127.5, 124.0, 119.9, 109.9, 53.4, 31.4, 27.3, 24.2, 22.1, 21.6, 13.6.
Anal. Calcd for C20H25N5O2S: C, 60.13; H, 6.31; N, 17.53.
Found: C, 60.39; H, 6.33; N, 17.65.
1-(Ben zotr iazol-1-yl)-2-decan on e p-Tosylh ydr azon e (5b):
1H NMR δ 8.46 (s, 1 H), 8.00 (d, J ) 8.3 Hz, 1 H), 7.72 (d, J )
8.3 Hz, 2 H), 7.35-7.19 (m, 4 H), 7.08 (d, J ) 8.2 Hz, 1 H),
5.30 (s, 2 H), 2.47 (s, 3 H), 2.06 (t, J ) 7.4 Hz, 2 H), 1.35-1.03
(m, 12 H), 0.85 (t, J ) 7.0 Hz, 3 H); 13C NMR δ 153.1, 146.1,
144.2, 134.9, 133.0, 129.6, 127.9, 127.4, 124.0, 119.8, 109.9,
53.4, 31.6, 29.4, 29.0, 28.9, 27.3, 24.5, 22.5, 21.6, 14.0. Anal.
Calcd for C23H31N5O2S: C, 62.56; H, 7.08; N, 15.86. Found:
C, 62.56; H, 7.26; N, 15.87.
1-(Ben zotr ia zol-1-yl)-2-u n d eca n on e (4c): purified by
column chromatography using EtOAc/hexane (1:3) as the
1
eluent; H NMR δ 8.06 (d, J ) 8.2 Hz, 1 H), 7.51-7.45 (m, 1
H), 7.40-7.34 (m, 2 H), 5.42 (s, 2 H), 2.46 (t, J ) 7.3 Hz, 2 H),
1.67-1.53 (m, 2 H), 1.37-1.28 (m, 12 H), 0.87 (t, J ) 6.6 Hz,
3 H); 13C NMR δ 202.2, 145.8, 133.4, 127.8, 124.0, 120.0, 109.1,
56.1, 39.7, 31.7, 29.2, 29.1, 29.0, 28.9, 23.1, 22.5, 14.0. Anal.
Calcd for C17H25N3O: C, 71.05; H, 8.77; N, 14.62. Found: C,
70.81; H, 8.96; N, 14.64.
1-(Ben zotr ia zol-1-yl)-p-m eth yla cetop h en on e (4d ): pu-
1
rified by recrystallization from EtOAc/hexane (1:4); H NMR
δ 8.01 (d, J ) 8.1 Hz, 1 H), 7.88 (d, J ) 8.1 Hz, 2 H), 7.44-
7.19 (m, 5 H), 6.02 (s, 2 H), 2.39 (s, 3 H); 13C NMR δ 189.9,
145.8, 145.4, 133.7, 131.3, 129.6, 128.1, 127.5, 123.7, 119.7,
109.5, 53.6, 21.6. Anal. Calcd for C15H13N3O: C, 71.70; H,
5.21; N, 16.72. Found: C, 71.55; H, 5.27; N, 16.85.
1-(Ben zotr ia zol-1-yl)-1-p h en yla cetop h en on e (4e): puri-
1
fied by recrystallization from EtOAc/hexane (1:4); H NMR δ
8.06-7.98 (m, 3 H), 7.89 (s, 1 H), 7.57-7.50 (m, 1 H), 7.43-
7.20 (m, 10 H); 13C NMR δ 192.6, 146.5, 134.4, 134.1, 133.1,
132.9, 129.4, 129.2, 129.1, 128.9, 128.8, 127.4, 123.8, 119.8,
111.3, 68.1. Anal. Calcd for C20H15N3O: C, 76.66; H, 4.82;
N, 13.41. Found: C, 76.78; H, 4.94; N, 13.31.
1-(Ben zotr iazol-1-yl)-1-pyr r olyl-2-octadecan on e (4f): pu-
rified by column chromatography using EtOAc/hexane (1:3)
as the eluent; 1H NMR δ 8.06 (d, J ) 8.3 Hz, 1 H), 7.48-7.26
(m, 4 H), 6.89 (t, J ) 2.2 Hz, 2 H), 6.26 (t, J ) 2.2 Hz, 2 H),
2.71-2.51 (m, 2 H), 1.72-1.60 (m, 2 H), 1.35-1.18 (m, 26 H),
0.87 (t, J ) 6.7 Hz, 3 H); 13C NMR δ 199.1, 146.1, 132.3, 128.4,
124.5, 120.8, 120.2, 110.8, 110.0, 75.2, 39.7, 31.9, 29.7, 29.6,
29.59, 29.55, 29.5, 29.3, 29.2, 28.8, 23.4, 22.6, 14.0. Anal. Calcd
for C28H42N4O: C, 74.62; H, 9.39; N, 12.43. Found: C, 75.03;
H, 9.72; N, 12.38.
1-(Ben zotr iazol-1-yl)-1-(ph en ylth io)-p-m eth ylacetoph e-
n on e (4g): purified by recrystallization from EtOAc/hexane
(1:4); 1H NMR δ 8.05-7.95 (m, 4 H), 7.81 (s, 1 H), 7.54 (t, J
) 7.8 Hz, 1 H), 7.39 (t, J ) 7.7 Hz, 1 H), 7.30-7.22 (m, 3 H),
7.20 (t, J ) 7.7 Hz, 2 H), 7.12 (d, J ) 8.2 Hz, 2 H), 2.39 (s, 3
H); 13C NMR δ 188.5, 146.9, 145.9, 133.5, 132.1, 130.7, 129.7,
129.4, 129.3, 127.7, 124.3, 120.0, 113.1, 71.2, 21.8. Anal. Calcd
for C21H17N3OS: C, 70.17; H, 4.77; N, 11.69. Found: C, 69.97;
H, 4.77; N, 11.82.
1-(Ben zot r ia zol-1-yl)-1-(p h en ylt h io)-2-n on a d eca n on e
(4h ): purified by column chromatography using EtOAc/hexane
1
(1:3) as the eluent; H NMR δ 8.06 (d, J ) 8.4 Hz, 1 H), 7.80
(d, J ) 8.4 Hz, 1 H), 7.53 (t, J ) 8.2 Hz, 1 H), 7.45 (t, J ) 8.2
Hz, 1 H), 7.30-7.12 (m, 5 H), 6.97 (s, 1 H), 2.90-2.76 (m, 1
H), 2.67-2.55 (m, 1 H), 1.72-1.59 (m, 2 H), 1.38-1.20 (m, 28
H), 0.91 (t, J ) 6.7 Hz, 3 H); 13C NMR δ 199.5, 146.8, 133.3,
132.0, 130.5, 129.4, 129.2, 127.7, 124.3, 120.1, 112.3, 74.0, 39.8,
31.9, 29.6, 29.54, 29.47, 29.3, 29.1, 28.8, 23.6, 22.6, 14.0. Anal.
Calcd for C31H45N3OS: C, 73.33; H, 8.93; N, 8.28. Found: C,
73.48; H, 9.26; N, 8.36.
1-(Be n zot r ia zol-1-yl)-1-p h e n oxy-p -m e t h yla ce t op h e -
n on e (13a ): purified by recrystallization from EtOAc/hexane
(1:4); 1H NMR δ 8.06 (s, 1 H), 8.04-7.97 (m, 3 H), 7.76 (d, J )
9.1 Hz, 1 H), 7.47 (t, J ) 7.7 Hz, 1 H), 7.34 (t, J ) 7.7 Hz, 1
H), 7.28-7.23 (m, 4 H), 7.09 (d, J ) 8.6 Hz, 2 H), 7.03 (t, J )
7.4 Hz, 1 H), 2.39 (s, 3 H); 13C NMR δ 187.2, 155.5, 146.6,
145.9, 132.2, 130.6, 129.9, 129.7, 129.4, 128.3, 124.5, 123.6,
1-(Ben zotr ia zol-1-yl)-2-u n d eca n on e p-Tosylh yd r a zon e
(5c): H NMR δ 8.47 (s, 1 H), 8.00 (d, J ) 8.5 Hz, 1 H), 7.72
1
(d, J ) 8.2 Hz, 2 H), 7.36-7.19 (m, 4 H), 7.07 (d, J ) 8.2 Hz,
1 H), 5.30 (s, 2 H), 2.47 (s, 3 H), 2.11-2.00 (m, 2 H), 1.37-
0.98 (m, 14 H), 0.87 (t, J ) 7.0 Hz, 3 H); 13C NMR δ 153.1,
146.1, 144.2, 134.9, 133.0, 129.6, 127.9, 127.4, 124.0, 119.8,
109.9, 53.4, 31.7, 29.4, 29.2, 29.1, 29.0, 27.4, 24.6, 22.5, 21.6,
14.0. Anal. Calcd for C24H33N5O2S: C, 63.27; H, 7.30; N,
15.37. Found: C, 62.99; H, 7.51; N, 15.24.
1-(Ben zotr ia zol-1-yl)-2-(p-tolyl)eth a n -2-on e p-Tosylh y-
d r a zon e (5d ): 1H NMR δ 8.06-7.98 (m, 1 H), 7.75 (s, 1 H),
7.65 (d, J ) 8.3 Hz, 2 H), 7.41-7.32 (m, 3 H), 7.28 (d, J ) 8.3
Hz, 2 H), 7.13 (d, J ) 7.9 Hz, 2 H), 6.84 (d, J ) 7.9 Hz, 2 H),
5.60 (s, 2 H), 2.47 (s, 3 H), 2.30 (s, 3 H); 13C NMR δ 149.7,
146.1, 144.4, 141.2, 135.0, 133.1, 130.5, 129.7, 127.9, 127.6,

4146 J . Org. Chem., Vol. 62, No. 12, 1997
Katritzky et al.
126.8, 126.0, 124.0, 119.9, 109.9, 54.0, 21.7, 21.3. Anal. Calcd
for C22H21N5O2S: C, 62.99; H, 5.05; N, 16.69. Found: C, 62.94;
H, 5.07; N, 16.79.
δ 155.9, 151.7, 146.1, 144.0, 134.3, 132.2, 129.8, 129.3, 127.8,
127.6, 124.2, 123.4, 119.6, 116.0, 112.0, 87.7, 31.4, 29.5, 28.7,
27.3, 24.8, 22.4, 21.5, 13.9. Anal. Calcd for C28H33N5O3S: C,
64.72; H, 6.40; N, 13.48. Found: C, 64.92; H, 6.62; N, 13.26.
1-(Ben zotr ia zol-1-yl)-2-p h en yleth a n -2-on e p-Tosylh y-
d r a zon e (21b): mp 158-160 °C; 1H NMR δ 8.08-8.00 (m, 1
H), 7.84 (s, 1 H), 7.66 (d, J ) 7.5 Hz, 2 H), 7.50-7.25 (m, 8 H),
7.01-6.90 (m, 2 H), 5.66 (s, 2 H), 2.50 (s, 3 H); 13C NMR δ
149.4, 146.0, 144.4, 134.9, 133.1, 130.7, 129.8, 129.7, 129.1,
127.9, 127.6, 126.8, 124.0, 119.9, 109.8, 53.9, 21.6. Anal. Calcd
for C21H19N5O2S: C, 62.21; H, 4.72; N, 17.27. Found: C, 62.15;
H, 4.68; N, 17.31.
2-(Ben zotr ia zol-1-yl)-2-p h en yla cetop h en on e p-Tosyl-
h yd r a zon e (5e): 1H NMR δ 8.08-8.02 (m, 1 H), 7.70 (br s, 1
H), 7.40-7.30 (m, 11 H), 7.24-7.18 (m, 3 H), 7.14 (d, J ) 14.9
Hz, 2 H), 7.04 (d, J ) 8.5 Hz, 2 H), 2.39 (s, 3 H); 13C NMR δ
151.3, 144.2, 143.0, 134.2, 133.7, 133.0, 130.7, 130.0, 129.8,
129.4, 129.0, 128.8, 127.6, 127.4, 123.9, 119.7, 111.9, 68.2, 21.6.
Anal. Calcd for C27H23N5O2S: C, 67.34; H, 4.81; N, 14.54.
Found: C, 67.01; H, 4.79; N, 14.36.
1-(Ben zotr ia zol-1-yl)-1-p yr r olyl-2-octa d eca n on e p-To-
1
sylh yd r a zon e (5f): H NMR δ 8.51 (s, 1 H), 7.97 (d, J ) 8.9
2-(Ben zotr ia zol-1-yl)-3-p h en ylp r op a n -3-on e p-Tosylh y-
1
Hz, 1 H), 7.38 (s, 1 H), 7.37-7.23 (m, 2 H), 7.20-7.10 (m, 3
H), 6.94 (d, J ) 8.0 Hz, 2 H), 6.72 (t, J ) 2.2 Hz, 2 H), 6.14 (t,
J ) 2.2 Hz, 2 H), 2.38-2.23 (m, 5 H), 1.32-0.95 (m, 28 H),
0.80 (t, J ) 6.6 Hz, 3 H); 13C NMR δ 151.2, 146.2, 144.3, 134.1,
132.4, 129.4, 128.0, 127.6, 124.3, 120.5, 119.6, 111.5, 110.5,
74.1, 31.9, 29.6, 29.54, 29.50, 29.4, 29.3, 29.2, 29.0, 28.4, 24.6,
22.6, 21.5, 14.1. Anal. Calcd for C35H50N6O2S: C, 67.93; H,
8.14; N, 13.58. Found: C, 68.25; H, 8.43; N, 13.65.
d r a zon e (21c): mp 179-180 °C; H NMR δ 8.01 (d, J ) 7.9
Hz, 1 H), 7.72 (d, J ) 8.5 Hz, 2 H), 7.59 (s, 1 H), 7.40-7.24
(m, 8 H), 6.69 (d, J ) 8.0 Hz, 2 H), 5.91 (q, J ) 7.1 Hz, 1 H),
2.50 (s, 3 H), 1.92 (d, J ) 7.2 Hz, 3 H); 13C NMR δ 153.0, 146.4,
144.4, 135.1, 132.3, 130.6, 129.74, 129.71, 129.0, 127.9, 127.4,
126.8, 123.9, 120.1, 110.2, 60.6, 21.7, 16.8. Anal. Calcd for
C22H21N5O2S: C, 62.99; H, 5.05; N, 16.69. Found: C, 62.59;
H, 4.97; N, 16.62.
1-(Ben zotr iazol-1-yl)-1-(ph en ylth io)-p-m eth ylacetoph e-
n on e p-Tosylh yd r a zon e (5g): 1H NMR δ 7.98 (t, J ) 8.5
Hz, 2 H), 7.82 (s, 1 H), 7.53-7.46 (m, 3 H), 7.41 (t, J ) 10.8
Hz, 1 H), 7.23-7.13 (m, 5 H), 7.12-7.05 (m, 3 H), 7.02-6.96
(m, 4 H), 2.42 (s, 3 H), 2.31 (s, 3 H); 13C NMR δ 148.9, 146.7,
144.3, 141.4, 134.6, 133.4, 131.9, 131.1, 130.5, 129.5, 129.1,
129.0, 127.8, 127.4, 127.1, 125.7, 124.2, 119.7, 113.3, 71.7, 21.6,
21.3. Anal. Calcd for C28H25N5O2S2: C, 63.74; H, 4.78; N,
13.27. Found: C, 63.97; H, 4.65; N, 13.34.
1-(Ben zot r ia zol-1-yl)-1-(p h en ylt h io)-2-n on a d eca n on e
p-Tosylh yd r a zon e (5h ): 1H NMR δ 8.10 (br s, 1 H), 8.06-
7.96 (m, 1 H), 7.74-7.64 (m, 1 H), 7.61 (d, J ) 8.2 Hz, 2 H),
7.42-7.32 (m, 3 H), 7.25-7.16 (m, 2 H), 7.11 (t, J ) 7.4 Hz, 2
H), 7.00 (d, J ) 7.1 Hz, 2 H), 6.78 (s, 1 H), 2.44 (s, 3 H), 2.32-
2.20 (m, 1 H), 2.15-2.01 (m, 1 H), 1.40-1.00 (m, 30 H), 0.88
(t, J ) 6.6 Hz, 3 H); 13C NMR δ 152.0, 146.7, 144.3, 134.5,
133.4, 131.7, 129.5, 129.2, 129.0, 128.3, 128.0, 127.4, 124.2,
119.7, 113.2, 71.4, 31.9, 30.0, 29.7, 29.6, 29.57, 29.45, 29.31,
29.27, 29.0, 28.3, 24.8, 22.6, 21.6, 14.1. Anal. Calcd for
C38H53N5O2S2: C, 67.52; H, 7.90; N, 10.36. Found: C, 67.33;
H, 8.16; N, 10.47.
P r ep a r a tion of Acetylen es 9a -h , 18a -f, a n d 23a -c.
Gen er a l P r oced u r e. To a stirred suspension of the corre-
sponding (p-toluenesulfonyl) hydrazone 5a-h , 14a-f, or 21a-c
(2 mmol) in diethyl ether (40 mL) was added the appropriate
lithium reagent (6 equiv) (for compounds 9a -h and 21a -c,
n-butyllithium was used and for compounds 18a -f, see
Scheme 2 and Table 2) at -78 °C. After the mixture was
stirred for 0.5 h at -78 °C and 48 h at room temperature, the
reaction was quenched with water, and the solution was
extracted with diethyl ether and dried over anhydrous MgSO4.
Removal of the solvent via rotary evaporation gave a residue
which was subjected to column chromatography using pentane
or hexane as the eluent to provide the corresponding acetylene
9a -h , 18a -f, or 21a -c (Tables 1 and 2, Scheme 3).
1
1-Hep tyn e (9a ) 23a ): oil (lit.21 bp 99-100 °C); H NMR
δ 2.30-2.16 (m, 2 H), 1.93 (t, J ) 2.3 Hz, 1 H), 1.65-1.28 (m,
6 H), 0.91 (t, J ) 6.9 Hz, 3 H); 13C NMR δ 84.7, 68.0, 30.9,
28.2, 22.1, 18.3, 13.9.
1-Decyn e (9b): oil (lit.22 bp 60-62 °C/0.8 mmHg); 1H NMR
δ 2.60-2.55 (m, 2 H), 2.32 (t, J ) 2.3 Hz, 1 H), 1.95-1.68 (m,
12 H), 1.29 (t, J ) 6.1 Hz, 3 H); 13C NMR δ 84.5, 68.0, 31.8,
29.2, 29.1, 28.8, 28.5, 22.6, 18.4, 14.0.
1-Un d ecyn e (9c): oil (lit.23 bp 75-78 °C/10 mmHg); 1H
NMR δ 2.24-2.18 (m, 2 H), 1.96 (t, J ) 2.6 Hz, 1 H), 1.62-
1.49 (m, 2 H), 1.49-1.22 (m, 12 H), 0.91 (t, J ) 6.7 Hz, 3 H);
13C NMR δ 84.5, 68.0, 31.9, 29.5, 29.3, 29.1, 28.8, 28.5, 22.7,
18.4, 14.0.
1-(Be n zot r ia zol-1-yl)-1-p h e n oxy-p -m e t h yla ce t op h e -
1
n on e p-Tosylh yd r a zon e (14a ): H NMR δ 8.05-8.03 (m, 1
H), 7.78 (s, 1 H), 7.64-7.60 (m, 1 H), 7.49 (s, 1 H), 7.41-7.32
(m, 2 H), 7.30-7.22 (m, 4 H), 7.18- 7.06 (m, 6 H), 6.95 (t, J )
7.4 Hz, 1 H), 6.88 (d, J ) 8.8 Hz, 2 H), 2.38 (s, 3 H), 2.36 (s, 3
H); 13C NMR δ 155.9, 148.4, 146.3, 144.2, 141.3, 134.4, 132.3,
130.5, 129.7, 129.4, 127.8, 127.7, 127.66, 125.3, 124.3, 123.4,
119.6, 116.2, 112.4, 88.5, 21.5, 21.4. Anal. Calcd for
C28H25N5O3S: C, 65.74; H, 4.93; N, 13.69. Found: C, 66.10;
H, 5.03; N, 13.57.
Tolyla cetylen e (9d ) 9g): oil (lit.24 bp 64-66 °C); 1H NMR
δ 7.37 (d, J ) 8.2 Hz, 2 H), 7.10 (d, J ) 7.9 Hz, 2 H), 3.01 (s,
1 H), 2.33 (s, 3 H); 13C NMR δ 138.9, 132.0, 129.0, 119.0, 83.8,
76.4, 21.4.
1-(Ben zotr ia zol-1-yl)-1-p h en oxyh exa n -2-on e p-Tosyl-
h yd r a zon e (14b): 1H NMR δ 8.47 (s, 1 H), 8.07-8.01 (m, 1
H), 7.60-7.48 (m, 1 H), 7.46-7.39 (m, 2 H), 7.38-7.14 (m, 5
H), 7.12-6.82 (m, 5 H), 2.72-2.25 (m, 2 H), 2.35 (s, 3 H), 1.62-
1.41 (m, 2 H), 1.40-1.22 (m, 2 H), 0.82 (t, J ) 7.2 Hz, 3 H);
13C NMR δ 155.9, 151.5, 146.2, 144.1, 134.9, 132.2, 129.8,
129.3, 127.8, 127.6, 124.2, 123.4, 119.6, 116.0, 112.0, 87.7, 27.0,
26.8, 22.8, 21.5, 13.6. Anal. Calcd for C25H27N5O3S: C, 62.87;
H, 5.70; N, 14.66. Found: C, 63.14; H, 5.97; N, 14.81.
1-(Ben zotr ia zol-1-yl)-1-p h en oxy-2-p h en yleth a n -2-on e
p-Tosylh yd r a zon e (14c ) 14d ): 1H NMR δ 8.10-8.01 (m, 1
H), 7.78-7.70 (m, 1 H), 7.62-7.56 (m, 1 H), 7.54-7.43 (m, 3
H), 7.42-7.06 (m, 11 H), 6.96 (t, J ) 7.2 Hz, 1 H), 6.86 (d, J )
8.0 Hz, 2 H), 2.39 (s, 3 H); 13C NMR δ 155.9, 148.2, 146.4,
144.4, 134.4, 132.3, 131.0, 129.9, 129.8, 129.5, 129.4, 127.9,
127.8, 127.7, 124.3, 123.5, 119.6, 116.2, 112.3, 88.6, 21.6. Anal.
Calcd for C27H23N5O3S: C, 65.18; H, 4.66; N, 14.08. Found:
C, 65.05; H, 4.66; N, 14.12.
Dip h en yla cetylen e (9e ) 18d ): mp 59-60 °C (lit.8 mp 59-
60 °C); 1H NMR δ 7.53-7.50 (m, 4 H), 7.36-7.25 (m, 6 H); 13
NMR δ 131.5, 128.3, 128.2, 123.2, 89.4.
C
1-P yr r olyl-1-octa d ecyn e (9f): 1H NMR δ 6.83 (t, J ) 2.2
Hz, 2 H), 6.15 (t, J ) 2.2 Hz, 2 H), 2.34 (t, J ) 7.0 Hz, 2 H),
1.62-1.24 (m, 28 H), 0.90 (t, J ) 6.7 Hz, 3 H); 13C NMR δ
124.5, 109.5, 74.3, 65.9, 31.9, 29.7, 29.6, 29.5, 29.4, 29.3, 29.2,
28.9, 28.8, 22.7, 18.2, 14.1; HRMS (M+ + 1) calcd for C22H38
N
316.3004, found 316.2993.
1-Non a d ecyn e (9h ): mp 36-38 °C (lit.25 mp 37-38 °C); 1H
NMR δ 2.22-2.15 (m, 2 H), 1.94 (t, J ) 2.6 Hz, 1 H), 1.60-
1.26 (m, 30 H), 0.89 (t, J ) 6.8 Hz, 3 H); 13C NMR δ 84.8,
68.0, 31.9, 29.7, 29.6, 29.5, 29.4, 29.1, 28.1.
1-(p-Meth ylp h en yl)-1-h exyn e (18a ): 1H NMR δ 7.30 (d,
J ) 8.0 Hz, 2 H), 7.09 (d, J ) 8.0 Hz, 2 H), 2.41 (t, J ) 7.0 Hz,
2 H), 2.34 (s, 3 H), 1.66-1.42 (m, 4 H), 0.96 (t, J ) 7.3 Hz, 3
(21) Henne, A. L.; Greenlee, K. W. J . Am. Chem. Soc. 1945, 67, 484.
(22) Klein, J .; Gurfinkel, E. Tetrahedron 1970, 26, 2127.
(23) Epsztein, R.; Marszak, I. Mem. services chim. e´tat (Paris)1953,
38, 165; Chem. Abstr. 1956, 50, 2415b.
(24) Schlosser, M.; Ladenberger, V. Chem. Ber. 1967, 100, 3901.
(25) Coffman, D. D.; Tsao, J . C.-Y.; Schniepp, L. E.; Marvel, C. S. J .
Am. Chem. Soc. 1933, 55, 3792.
1-(Ben zotr ia zol-1-yl)-1-p h en oxy-2-n on a n on e p-Tosyl-
h yd r a zon e (14e ) 14f): H NMR δ 8.94 (s, 1 H), 8.10-8.02
(m, 1 H), 7.64-7.56 (m, 1 H), 7.43-7.32 (m, 2 H), 7.30-7.23
(m, 3 H), 7.20-7.15 (m, 2 H), 7.04 (d, J ) 8.1 Hz, 2 H), 7.00-
6.91 (m, 3 H), 2.61-2.40 (m, 2 H), 2.35 (s, 3 H), 1.60-1.42 (m,
2 H), 1.30-1.00 (m, 8 H), 0.81 (t, J ) 6.9 Hz, 3 H); 13C NMR
1

Transformation of Esters to Alkynes with Benzotriazoles
J . Org. Chem., Vol. 62, No. 12, 1997 4147
H); 13C NMR δ 137.3, 131.4, 128.9, 121.0, 89.5, 80.5, 30.9, 22.0,
21.4, 19.1, 13.6; HRMS (M+) calcd for C13H16 172.1252, found
172.1262.
P r ep a r a tion of Bifu n ction a l Keton e 27, Hyd r a zon e 28,
a n d Acetylen e 29. The procedures were the same as for the
preparation of monofunctional ketones, hydrazones, and acetyl-
enes as described above, except that 2 equiv of lithium reagent
25, tosylhydrazine, and n-butyllithium were used.
1,10-Bis(ben zotr ia zol-1-yl)-1,10-d ip h en yl-2,9-d eca n ed i-
on e (27): purified by column chromatography using EtOAc/
hexane (1:2) as the eluent; mp 63-65 °C; 1H NMR δ 8.06-8.03
(m, 2 H), 7.43-7.29 (m, 14 H), 7.26-6.89 (m, 2 H), 6.74 (s, 2
H), 2.59 (t, J ) 7.3 Hz, 4 H), 1.69-1.54 (m, 4 H), 1.30-1.18
(m, 4 H); 13C NMR δ 202.9, 146.3, 133.0, 132.4, 129.5, 129.2,
128.9, 127.6, 124.0, 120.1, 110.6, 71.3, 40.5, 28.4, 23.2. Anal.
Calcd for C34H32N6O2: C, 73.36; H, 5.79; N, 15.10. Found: C,
73.14; H, 5.63; N, 15.39.
5-Decyn e (18b): oil (lit.26 bp 172 °C/745 mmHg); 1H NMR
δ 2.14 (t, J ) 3.0, 4 H), 1.46-1.36 (m, 8 H), 0.90 (t, J ) 7.2
Hz, 6 H); 13C NMR δ 80.0, 31.3, 21.9, 18.4, 13.5.
1-P h en ylp r op yn e (18c ) 23c): oil (lit.27 bp 113 °C/84
1
mmHg); H NMR δ 7.76-7.66 (m, 2 H), 7.64-7.54 (m, 3 H),
2.33 (s, 3 H); 13C NMR δ 131.4, 128.1, 127.4, 124.0, 85.7, 79.7,
4.2.
1-P h en yl-1-n on yn e (18e): oil; 1H NMR δ 7.43-7.35 (m, 2
H), 7.30-7.23 (m, 3 H), 2.40 (t, J ) 7.1 Hz, 2 H), 1.66-1.54
(m, 2 H), 1.50-1.40 (m, 2 H), 1.39-1.20 (m, 6 H), 0.90 (t, J )
6.7 Hz, 3 H); 13C NMR δ 131.5, 128.1, 127.4, 124.1, 90.5, 80.6,
31.8, 28.9, 28.84, 28.79, 22.6, 19.4, 14.1; HRMS (M+) calcd for
C15H20 200.1565, found 200.1567.
1,10-Bis(ben zotr ia zol-1-yl)-1,10-d ip h en yl-2,9-d eca n ed i-
on e bis-p-tosylh yd r a zon e (28): purified by recrystallization
1
1
from acetone/hexane; mp 190-191 °C; H NMR δ 10.50 (s, 2
2-Decyn e (18f): oil (lit.22 bp 61 °C/0.8 mmHg); H NMR δ
H), 7.98 (d, J ) 7.7 Hz, 2 H), 7.38-7.26 (m, 14 H), 7.20-7.14
(m, 6 H), 7.10 (d, J ) 8.0 Hz, 4 H), 6.83 (s, 2 H), 2.38 (s, 6 H),
2.33-2.22 (m, 4 H), 1.36-1.03 (m, 8 H); 13C NMR δ 154.5,
145.3, 142.6, 135.2, 134.2, 132.5, 128.6, 128.1, 128.0, 127.1,
126.7, 123.3, 118.8, 111.0, 66.3, 28.7, 28.3, 23.8, 20.9. Anal.
Calcd for C48H48N10O4S2: C, 64.55; H, 5.42; N, 15.68. Found:
C, 64.93; H, 5.53; N, 15.49.
2.16-2.06 (m, 2 H), 1.77 (t, J ) 2.5 Hz, 3 H), 1.52-1.20 (m,
10 H), 0.88 (t, J ) 6.7 Hz, 3 H); 13C NMR δ 79.3, 75.2, 31.8,
29.1, 28.9, 22.6, 18.7, 14.0, 3.4.
P h en ylen e (23b ): oil (lit.28 bp 73-74 °C/80 mmHg); 1H
NMR δ 7.62-7.46 (m, 2 H), 7.42-7.28 (m, 3 H), 3.07 (s, 1 H);
13C NMR δ 132.1, 128.7, 128.3, 122.1, 83.6, 77.1.
P r ep a r a tion of r-(Ben zotr ia zol-1-yl) Keton es 22a -c
fr om r-(Ben zotr ia zol-1-yl) Ester s 20a ,b. An R-(benzotria-
zol-1-yl) ester 20a or 20b (10 mmol) was dissolved in dry THF/
diethyl ether (100 mL, 1:1) and cooled to -78 °C. Grignard
reagent (pentylmagnesium iodide or phenylmagnesium bro-
mide) (15 mmol) in diethyl ether (15 mL) was slowly added
with stirring. The mixture was allowed to warm to -40 °C,
stirred overnight at -40 °C, and then poured into a saturated
ammonium chloride solution followed by extraction with
diethyl ether (3 × 25 mL). The combined organic extracts were
washed with saturated brine (2 × 60 mL), dried with MgSO4,
and filtered. Removal of the solvent gave the residue, which
was chromatographed on silica, using ethyl acetate/hexane (1:
4) as the eluent, to afford the corresponding ketone (20a -c).
1-(Ben zotr ia zol-1-yl)a cetop h en on e (22b): mp 112-113
°C (lit.29 mp 109-111 °C); 1H NMR δ 8.11-7.97 (m, 3 H), 7.68-
7.25 (m, 6 H), 6.06 (s, 2 H); 13C NMR δ 190.4, 145.8, 134.3,
133.8, 133.7, 128.9, 128.1, 127.6, 123.8, 119.8, 109.4, 53.7.
1-P h en yl-2-(1-ben zotr ia zol-1-yl)p r op a n on e (22c): mp
1,10-Dip h en yl-1,9-d eca d iyn e (29): purified by column
chromatography using pentane as the eluent; oil; H NMR δ
7.43-7.35 (m, 4 H), 7.31-7.21 (m, 6 H), 2.42 (t, J ) 6.9 Hz, 4
H), 1.70-1.48 (m, 8 H); 13C NMR δ 131.5, 128.1, 127.4, 126.9,
90.2, 80.7, 28.6, 28.4, 19.4; Anal. Calcd for C22H22: C, 92.26;
H, 7.74. Found: C, 92.06; H, 7.55.
1
Note Ad d ed in P r oof. It is likely that the large
excess of BuLi required is due to ring lithiation of the
tosyl group and that a stoichiometric amount of BuLi
could be used if MeC6H4SO2NHNH2 was replaced by the
(2,4,6-triisopropylphenyl)sulfonyl analog (cf. Chamberlin,
A. R.; Stemke, J . E.; Bond, F. T. J . Org. Chem. 1978, 43,
147). We thank Dr. Rob Adlington (Oxford) for calling
our attention to this point.
Ack n ow led gm en t. We thank Dr. Radi Awartani for
helpful discussions and Farchan Laboratories for pro-
viding us with certain authentic acetylenes for com-
parison with our products.
1
159-161 °C; H NMR δ 8.06-7.96 (m, 2 H), 7.69-7.25 (m, 7
H), 6.72 (q, J ) 7.2 Hz, 1 H), 1.96 (d, J ) 7.2 Hz, 3 H); 13C
NMR δ 193.7, 146.2, 133.9, 133.8, 131.9, 128.7, 128.4, 127.4,
123.8, 119.8, 110.1, 59.1, 16.1. Anal. Calcd for C15H13N3O:
C, 71.70; H, 5.21; N, 16.72. Found: C, 71.67; H, 5.35; N, 16.85.
Su p p or tin g In for m a tion Ava ila ble: HRMS and NMR
spectra of compounds 9f, 18a , and 18e (12 pages). This
material is contained in libraries on microfiche, immediately
follows this article in the microfilm version of the journal, and
can be ordered from the ACS; see any current masthead page
for ordering information.
(26) Vaughn, T. H.; Hennion, G. F.; Vogt, R. R.; Nieuwland, J . A. J .
Org. Chem. 1937, 2, 17.
(27) Campbell, K. N.; O’Connor, M. J . J . Am. Chem. Soc. 1939, 61,
2897.
(28) Campbell, K. N.; Campbell, B. K. Organic Syntheses; J ohn Wiley
& Sons: New York, 1963; Collect. Vol. 4, p 763.
(29) Katritzky, A. R.; Wrobel, L.; Savage, G. P.; Deyrup-Drewniak,
M. Aust. J . Chem. 1990, 43, 133.
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