Te-1-acylmethyl and Te-1-iminoalkyl telluroesters: Synthesis and thermolysis leading to 1,3-diketones and O-alkenyl and O-imino esters

Article abstract of DOI:10.1080/10426501003769728

A series of Te-1-acylmethyl carbotelluroates was prepared in good isolated yields from the reaction of potassium carbotelluroates with -haloketones in acetonitrile. Thermolysis of the telluroesters afforded vinyl esters in 20-50% yields, while treatment of the carbotellurorates with potassium t-butanolate led to 1,3-diketones in 30-75% yields with the liberation of black tellurium. The reaction of potassium carbotelluroates with -haloaceto oximes gave O-acyl oximes in 50-70% yields via Te-1-iminomethylcarbotelluroates. Copyright Taylor & Francis Group.

Full text of DOI:10.1080/10426501003769728

This article was downloaded by: [University of Saskatchewan Library]
On: 19 February 2013, At: 04:59
Publisher: Taylor & Francis
Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered
office: Mortimer House, 37-41 Mortimer Street, London W1T 3JH, UK
Phosphorus, Sulfur, and Silicon and the
Related Elements
Publication details, including instructions for authors and
subscription information:
http://www.tandfonline.com/loi/gpss20
Te-1-Acylmethyl and Te-1-Iminoalkyl
Telluroesters: Synthesis and Thermolysis
Leading to 1,3-Diketones and O-Alkenyl
and O-Imino Esters
Shoho Nakaiida a , Shinzi Kato b , Osamu Niyomura a , Masaru Ishida a
, Fumio Ando b & Jugo Koketsu b
a Department of Chemistry, Faculty of Engineering, Gifu University,
Gifu, Japan
b Department of Applied Chemistry, College of Engineering, Chubu
University, Kasugai, Japan
Version of record first published: 27 May 2010.
To cite this article: Shoho Nakaiida , Shinzi Kato , Osamu Niyomura , Masaru Ishida , Fumio Ando &
Jugo Koketsu (2010): Te-1-Acylmethyl and Te-1-Iminoalkyl Telluroesters: Synthesis and Thermolysis
Leading to 1,3-Diketones and O-Alkenyl and O-Imino Esters, Phosphorus, Sulfur, and Silicon and the
Related Elements, 185:5-6, 930-946
To link to this article: http://dx.doi.org/10.1080/10426501003769728
PLEASE SCROLL DOWN FOR ARTICLE
Full terms and conditions of use: http://www.tandfonline.com/page/terms-and-conditions
This article may be used for research, teaching, and private study purposes. Any
substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing,
systematic supply, or distribution in any form to anyone is expressly forbidden.
The publisher does not give any warranty express or implied or make any representation
that the contents will be complete or accurate or up to date. The accuracy of any
instructions, formulae, and drug doses should be independently verified with primary
sources. The publisher shall not be liable for any loss, actions, claims, proceedings,
demand, or costs or damages whatsoever or howsoever caused arising directly or
indirectly in connection with or arising out of the use of this material.

Phosphorus, Sulfur, and Silicon, 185:930–946, 2010
Copyright ꢀC Taylor & Francis Group, LLC
ISSN: 1042-6507 print / 1563-5325 online
DOI: 10.1080/10426501003769728
Te -1-ACYLMETHYL AND Te -1-IMINOALKYL
TELLUROESTERS: SYNTHESIS AND THERMOLYSIS
LEADING TO 1,3-DIKETONES AND O-ALKENYL AND
O-IMINO ESTERS
Shoho Nakaiida,1 Shinzi Kato,2 Osamu Niyomura,1
Masaru Ishida,1 Fumio Ando,2 and Jugo Koketsu2
1Department of Chemistry, Faculty of Engineering, Gifu University, Gifu, Japan
2Department of Applied Chemistry, College of Engineering, Chubu University,
Kasugai, Japan
A series of Te-1-acylmethyl carbotelluroates was prepared in good isolated yields from the
reaction of potassium carbotelluroates with α-haloketones in acetonitrile. Thermolysis of the
telluroesters afforded vinyl esters in 20−50% yields, while treatment of the carbotellurorates
with potassium t-butanolate led to 1,3-diketones in 30−75% yields with the liberation of
black tellurium. The reaction of potassium carbotelluroates with α-haloaceto oximes gave
O-acyl oximes in 50−70% yields via Te-1-iminomethylcarbotelluroates.
Keywords 1,3-Diketones; detelluration; O-acyl iminoesters; Te-1-acylmethyl carbotelluroates;
telluroesters; thermolysis
INTRODUCTION
1,3-Diketones have been widely used as important starting compounds for the synthe-
sis of natural organic compounds. In 1971, Roth et al. reported the alkylative coupling via
sulfide contraction of S-1-acylmethyl carbothioates to be a general method for the synthesis
of enolizable β-dicarbonyl compounds.1 In this reaction, trivalent phosphorous compounds
as desulfurization agents have been used in the presence of a base such as potassium tert-
pentanolate at 50−80◦C. Deselenation reactions of Se-1-acylmethyl carboselenoates were
found to proceed in the presence of an equimolar amount of the base at room temperature
under mild conditions to afford 1,3-diketones in good yields.2 The 1,3-diketone synthesis
using Te-1-acylmethyl telluroesters is expected to proceed under more mild conditions. To
the best of our knowledge, the synthesis of Te-1-acylmethyl telluroesters has not yet been
described, most likely due to the difficulty of their synthesis and purification. We have es-
tablished a method for preparing alkali metal carbotelluroates, which are important starting
Received 20 October 2008; accepted 18 November 2008.
Dedicated to Professor Naomichi Furukawa on the occasion of his 70th birthday.
This research was supported partially by a Grant-in-Aid for Scientific Research on Priority Areas from the
Ministry of Education, Science, Sports and Culture of Japan. Nippon Soda Co., Ltd. kindly provided a sample of
3-chloro-2,6-dimethoxybenzoyl chloride.
Address correspondence to Prof. Shinzi Kato, Maruno-uchi 2-14-32, Lions-City Maruno-uchi 1105, Naka-
ku, Nagoya 460-0002, Japan. E-mail: kshinzi@nifty.com
930

SYNTHESIS AND THERMOLYSIS OF TELLUROESTERS
931
compounds for the synthesis of telluroesters.3 The preparation of Te-α-functionalized-alkyl
telluroesters using alkali metal carbotelluroates has also not yet been reported.4 We present
here the synthesis of Te-1-acylmethyl and Te-1-iminomethyl carbotelluroates, as well as
the thermolysis and base treatment leading to 1,3-diketones and vinyl esters, respectively.
RESULTS AND DISCUSSION
Initially, the reaction conditions for the synthesis of Te-1-acylmethyl carbotelluroates
2 were examined using sodium 2-methoxybenzenecarbotelluroate and phenacyl bromide.
These reactions resulted in the formation of di(2-methoxybenzoyl) ditelluride 3. The reac-
tion with potassium 2-methoxybenzenecarbotelluroate instead of the sodium salt in acetoni-
trile at –20◦C for 1 h afforded the expected Te-phenacyl 2-methoxybenzenecarbotelluroate
2o in good yield (Scheme 1).
K(RCOTe)
RCOTeCHR"COR'
-20 °C, 1 h, in CH3CN
2
R'COCH2X
Na(2-MeOC6H4COTe)
X = Cl, Br
(2-MeOC6H4COTe) 2
-20 °C, 1 h, in CH3CN
3
R
Yield, %
R"
R'
2a Et
2b i-Pr
2c n-Bu
2d Ph
2e
2f
2g
2h
2i
2j
2k
2l
t-Bu
t-Bu
4-BrC6H4
Me
Me
Et
t-Bu
Ph
Ph
4-BrC6H4
OEt
NH2
Ph
4-BrC6H4
H
H
H
H
Me
H
H
H
Me
H
H
H
H
H
H
H
H
86
94
78
83
83
66
90
97
81
86
90
88
81
48
93
78
91
2m 4-MeC6H4
2n
2o 2-MeOC6H4 Ph
2p 4-MeOC6H4 Me
2q
4-BrC6H4
Scheme 1
The reactions of other potassium carbotelluroates with α-haloketones under the con-
ditions mentioned above led to Te-1-acylmethyl telluroesters 2a−2n and 2p−2q in yields
of 48−97%.
In general, Te-alkyl carbotelluroates are labile thermally and towards oxygen. For
example, upon exposure to air, compound 2h gradually decomposed with the liberation of
black tellurium to give 1-phenylethenyl benzoate 4h. Under an argon atmosphere, heating
of Te-phenacyl benezenecarbotelluroate 2h at 80◦C resulted in complete decomposition
within 5 h to give 1-phenylethenyl benzoate 4h and benzoic anhydride 5 (R = Ph) in yields
of 32% and 10%, respectively, along with the liberation of elemental tellurium (Scheme 2).

932
S. NAKAIIDA ET AL.
50−120 °C
3−6 h
RCOTeCHR"COR'
2
RCOO
R'
CHR" + (RCO)2O
+
Te
4
5
R
R'
R" Yield, %
Et
i-Pr
4-BrC6H4
t-Bu
Ph
Ph
4-BrC6H4
Et
t-Bu
Ph
4-BrC6H4
Ph
H
H
H
45
30
40
4a
4b
4c
4d
4e
4f
4g
4h
4i
Me 42
n-Bu
Ph
H
H
H
H
H
36
45
32
32a
34
Me 40
H
H
4j
4k 4-MeC6H4 4-BrC6H4
32
20
4-MeOC6H4 4-BrC6H4
4l
aCompound 5 (R = Ph): 10%.
Scheme 2
Presumably, ethenyl esters 4 may be formed via the intramolecular attack of the α-carbonyl
oxygen to the carbonyl carbon neighboring the tellurium atom (structure A in Scheme
3). In the case of 2f, the formation of 1-methyl-1-propenyl ester 6 was observed along
with 1-ethylethenyl ester 4f, where the former resulted from the intramolecular 1,3 proton
rearrangement in 4f (Scheme 4).
RCOO
R"
H
O
C
R'
R
Te
CHR"
(Z)-4
(E)-4
-Te
2
+
O
C
RCOO
R'
H
R'
R"
A
Scheme 3
Treatment of S-1-acylmethyl carbothioates with a base in the presence of a desul-
furizing agent such as triphenylphosphine and lithium salts such as lithium perchlorate
is known to afford 1,3-diketones in moderate yields.1 In contrast, without triorganophos-
phines and lithium salts such as LiClO4, Se-1-acylmethyl carboselenoates are converted
H
H
O
O
Me
H
R
O
C
H
R
O
C Me
Me
H
4f
6
Scheme 4

SYNTHESIS AND THERMOLYSIS OF TELLUROESTERS
933
to 1,3-diketones upon treatment with potassium tert-pentanolate.2 In the expectation of
obtaining 1,3-diketones, we examined the reaction of Te-1-acylmethyl carbotelluroates 2
with a base under several conditions. Treatment of 2 with potassium tert-butanolate at 20◦C
for 24 h was found to lead to the corresponding 1,3-diketones 7 in 20−45% yields with the
liberation of black tellurium (Scheme 5).
Scheme 5
A possible mechanism for the formation of 7 is shown in Scheme 6, which involves
the initial deprotonation of an active methylene group by potassium tert-butanolate, in-
tramolecular attack of the resulting anion (10) on the carbonyl carbon atom, and finally
elimination of the tellurium atom from the intermediately formed tellane (11) (Scheme 6).
Scheme 6
Previously, we reported the synthesis of 1,3-thiazoles from N-hydroxyiminomethyl
carbodithioates.5 To the best of our knowledge, Te-N-hydroxyiminomethyl carbotelluroates
and 1,3-tellurazoles have not been described in the literature,4a,c,d In the expectation of
obtaining these tellurium isologues, we investigated the reactions of 1 with α-halo oximes
(Scheme 7).

934
S. NAKAIIDA ET AL.
R
R
Scheme 7
The reactions of potassium carbotelluroates 1 with acetoxime (12) proceeded at
0−20◦C to form a mixture of syn- and anti N-1-hydroxyiminomethyl carbotelluroates
(13) in good yields, which quickly decomposed at room temperature to give syn- and
anti-O-acyl oximes (14).6 One plausible mechanism for the formation of 14 is shown in
Scheme 8, which involves detelluration of the cyclic intermediate B, which is formed by
intramolecular attack of the hydroxy oxygen atom to the carbonyl carbon atom in 13 and
subsequent 1,3-proton shift in the resulting O-1-ethenylamino ester (15) (Scheme 8).
Scheme 8
CONCLUSIONS
We have demonstrated that potassium carbotelluroates readily reacted with α-
haloketons to afford Te-1-acylmethyl telluroesters in good yields. Thermolysis of the
telluroesters leads to vinyl esters, while treatment of the telluroesters with potassium tert-
butanolate results in the formation of 1,3-diketones in moderate yields. Moreover, we have
described the one-pot conversion of N-1-hydroxyiminomethyl carbotelluroates, which are

SYNTHESIS AND THERMOLYSIS OF TELLUROESTERS
935
readily obtained from the reaction of potassium carbotelluroates with acetoxime to O-acyl
oximes. The operational simplicity and mild reaction conditions of these reactions not only
offer some useful synthetic methods of vinyl esters, 1,3-diketones and O-acyl oximes, but
also provide also a new C−C bond-forming reaction.
EXPERIMENTAL
All manipulations were carried out under argon. Melting points were determined
with a Yanagimoto micro-melting point apparatus and are uncorrected. The IR spectra
were measured with JASCO grating IR, Perkin-Elmer FT-IR 1640 and Shimazu FTIR
spectrophotometers using KBr disc unless stated otherwise. 1H (270 MHz) and 13C NMR
(67.8 MHz) spectra were measured with a JEOL JNX-GX with tetramethylsilane as an
internal standard. The mass spectra were obtained with a Hitachi RMU-6M high resolution
mass spectrometer and a Shimadzu GCMS QP1000 and QP9020-DF (EI, mode) high res-
olution mass spectrometer. Elemental analyses were performed by the Elemental Analysis
Center of Kyoto University.
Materials
Tellurium (particles), which was powdered prior to use, sodium and potassium metals,
phenacyl bromide, 4-bromophenacyl bromide, chloroacetophenone, 3-chloro-2-butanone,
ethyl bromoacetate, 2-chloroacetoamide, and potassium tert-butanolate were purchased
from Nacalai Tesque Co. (Kyoto, Japan). Sodium and potassium carbotelluroates were
prepared by reacting the corresponding alkali metal with acyl chlorides according to the
literature.3 2-Methoxybenzoyl, 4-methoxybenzoyl, and 4-methylbenzoyl chlorides were
prepared according to the literature.7 3-Chloro-2,6-dimethoxybenzoyl chloride (purity:
99.9%) was supplied from Nippon Soda Co., Ltd.
Acetonitrile and dichloromethane were distilled under nitrogen atmosphere from
phosphorus pentoxide. Ether and tetrahydrofuran were distilled from sodium benzophenone
ketyl under nitrogen atmosphere. 2-Bromopropiophenone was prepared by bromination of
propiophenone with bromine, according to the known method. α-Haloacetophenone oximes
were prepared according to literature.8
Chloroacetone Oxime
Hydroxylamine hydrochloride (8.34 g, 40 mmol) and chloroacetone (3.70 g, 40
mmol) in ethanol (30 mL) were stirred at 20◦C for 24 h. After removal of the solvent, the
residue was extracted with ether (100 mL), followed by washing with water and drying
over anhydrous sodium sulfate. Vacuum distillation gave 2.06 g (48%) of chloroacetone
oxime (syn/anti = 90:10) as colorless liquid: bp 75−78◦C/15 Torr.; IR (KBr): 3300, 1430,
1370, 1280, 1250, 1160, 1025, 890, 710 cm−1; 1H NMR (CDCl3) anti-conformer: δ = 2.02
(s, CH3), 4.09 (s, CH2Cl); syn-conformer: δ = 2.04 (s, CH3), 4.29 (s, CH2Cl); 9.70 (br,
OH); 13C NMR (CDCl3) δ = 11.9, 17.9 (CH3), 36.3, 45.4 (CH2Cl), 154.1, 154.8 (C N).
α-Bromoacetophenone Oxime
Yield 1.80 g (56%) (syn/anti = 55:45); mp 90−92◦C (colorless needles); IR (KBr)
3300, 1460, 1330, 1220, 1080, 955, 760, 690, 650 cm−1; 1H NMR (CDCl3): anti-conformer:

936
S. NAKAIIDA ET AL.
δ = 4.43 (s, CH2Cl); syn-conformer: δ = 4.62 (s, CH2Cl); 9.55 (br, OH); 13C NMR (CDCl3):
δ = 17.7, 32.3 (CH2Br), 126.2−133.3 (arom-ring), 154.3, 154.4 (C N).
α,4ꢀ-Dibromoacetophenone Oxime
Yield 3.43 g (59%) (syn/anti = 55:45); mp 111−113◦C (colorless needles); IR (KBr,
1
neat): 1590, 1490, 1320, 1070, 960, 920, 830, 775, 730, 510 cm−1; H NMR (CDCl3):
anti-conformer: δ = 4.39 (s, CH2Cl); syn-conformer: δ = 4.58 (s, CH2Cl); 7.56 (s, 4H,
arom-H), 8.96 (br, 1H, OH).
O-Methylchloroacetone Oxime
Yield 725 mg (24%) (syn/anti = 90:10); bp 53−55◦C/30 Torr (colorless liquid);
1H NMR (CDCl3): anti-conformer: δ = 1.95 (s, CH3), 3.88 (s, CH3O), 4.07 (s, CH2Cl);
syn-conformer: δ = 2.01 (s, CH3), 3.86 (s, CH3O), 4.21 (s, CH2Cl).
Typical procedures for the synthesis, thermolysis, and treatment of Te-α-ketoalkyl
carbotelluroates (2) with tert-butanolate are described below. Compounds 2 were identified
by comparison of their IR spectra with those of authentic samples prepared by the reaction
of the corresponding sodium carbotelluroate with haloketones.
Te -2,2-Dimethylpropanoylmethyl Ethanecarbotelluroate (2a)
A solution of potassium ethanecarbotelluroate (0.99 mmol) in THF (5 mL) was added
to a solution of 1-bromopinacolone (123 mg, 0.69 mmol) in acetonitrile (5 mL), and the
mixture was stirred at –20◦C for 1 h. Filtration of the black precipitate and evaporation of
the solvent under reduced pressure (0◦C/8 Torr) gave 170 mg (86%) of 2a as yellow liquid:
IR (KBr): 3000, 1700 (C O), 1685 (C O), 1475, 1360, 1280, 1150, 1000, 900, 670, 540
cm−1; 1H NMR (CDCl3): δ = 1.16 (t, J = 7.7 Hz, 3H, CH3), 1.23 (s, 9H, CH3), 2.64 (q,
J = 7.7 Hz, 2H, CH2), 3.98 (s, 2H, CH2Te); 13C NMR (CDCl3): δ = 9.0 (CH2Te), 15.3
(CH3), 26.8 (CH3), 44.6 (C CO), 48.2 (CH2CO), 202.6 (C O), 213.2 (C O); MS (CI):
m/z = 286, 284, 282 (M+1).
Te -2,2-Dimethylpropanoylmethyl 1-Metylethanecarbotelluroate (2b)
Similarly to 2a, the reaction of potassium benzenecarbotelluroate (1.78 mmol) with
1-bromopinacolone (165 mg, 0.92 mmol) gave 260 mg (94%) of 2b as yellow liquid:
IR (KBr, neat): 3100, 2950, 16600 (C O), 1595 (C O), 1580, 1450, 1360, 1230, 1200,
1
1170, 860, 760, 680, 660, 595 cm−1; H NMR (CDCl3): δ = 2.37 (s, 3H, CH3), 3.94
(s, 2H, CH2Te); 13C NMR (CDCl3): δ = 14.9 (CH2Te), 18.1 (CH3), 26.8 (CH3), 44.6
(C CO), 52.0 (CH2CO), 207.8, 213.1 (C O); MS (CI): m/z = 301, 299, 297 (M+1), 101
(CH2COC4H9).
Te -4-Bromophenacyl 1-Butanecarbotelluroate (2c)
Similarly to 2a, a solution of potassium 1-butanecarbotelluroate (1.06 mmol) in THF
(5 mL) was added to a solution of 4-bromophenacyl bromide (208 mg, 0.75 mmol) in
acetonitrile (5 mL), and the mixture was stirred at –20◦C for 1 h. Filtration of the black

SYNTHESIS AND THERMOLYSIS OF TELLUROESTERS
937
precipitate and evaporation of the solvent under reduced pressure (0◦C/8 Torr) gave 240
mg (78%) of Te-4-bromophenacyl 1-butanecarbotelluroate 2c as yellow liquid. IR (KBr):
3000, 2900, 1660 (C O), 1580, 1270, 1070, 1010, 845, 745 cm−1; 1H NMR (CDCl3): δ =
0.92 (t, J = 7.7 Hz, 3H, CH3), 1,38 (m, 2H, CH2), 1.65 (m, 2H, CH2), 2.66 (t, J = 7.7 Hz,
2H, CH2CO), 4.32 (s, 2H, CH2Te), 7.47−7.74 (m, 4H, arom-H); 13C NMR (CDCl3): δ =
13.6 (CH3), 15.3 (CH2Te), 21.7, 26.9, 54.5 (CH2), 126−133.6 (arom. ring), 196.9, 201.2
(C O); MS (CI) m/z 416, 414, 412 (M+1), 84 (C4H9CO).
Te -Acetylmethyl Benzenecarbotelluroate (2d)
Similarly to 2a, the reaction of potassium benzenecarbotelluroate (1.78 mmol) with
chloroacetone (115 mg, 1.25 mmol) gave 300 mg (83%) of 2d as yellow liquid. IR (KBr,
neat): 3100, 2950, 1660 (C O), 1590 (C O), 1580, 1450, 1360, 1200, 1170, 865, 760,
1
680, 660, 595 cm−1; H NMR (CDCl3): δ = 2.37 (s, 3H, CH3), 3.94 (s, 2H, CH2Te),
7.42−7.73 (m, 5H, arom-H); 13C NMR (CDCl3): δ = 20.2 (CH2Te), 27.6 (CH3), 126.9,
129.0, 134.2, 141.8 (arom. ring), 194.0 (C O), 205.7 (COTe); MS (CI): m/z = 293, 291,
289 (M+1), 105 (C6H5CO); HRMS calcd. for C10H10O2Te: 291.9743, found: 291.9748.
Te -1-Acetylethyl Benzenecarbotelluroate (2e)
Similarly to 2a, the reaction of potassium 1-methylethanecarbotelluroate (1.18 mmol)
with 1-bromo-2-butanone (125 mg, 0.83 mmol) gave 210 mg (83%) of 2e as yellow liquid.
IR (KBr, neat): 3000, 1690 (C O), 1660 (C O), 1575, 1440, 1200, 1170, 865, 760, 680,
1
660, 610, 590 cm−1; H NMR (CDCl): δ = 1.11 (t, J = 7.7 Hz, 2H, CH2), 3.95 (s, 2H,
CH2Te), 7.45−7.75 (m, 5H, arom-H); 13C NMR (CDCl3): δ = 8.5 (CH2Te), 27.6 (CH3),
126.9, 129.0, 143.2, 141.8 (arom. ring), 194.0 (C O), 209.0 (C O); MS (CI): m/z = 307,
305, 303 (M+1), 105 (C6H5CO).
Te -Propanoylmethyl Benzenecarbotelluroate (2f)
Similarly to 2a, the reaction of potassium benzenecarbotelluroate (2.43 mmol) with
2-chloro-2-butanone (181 mg, 1.70 mmol) gave 340 mg (66%) of 2f as yellow liquid. IR
(KBr, neat): 3100, 2920, 1690 (C O), 1660 (C O), 1570, 1440, 1170, 1000, 860, 760,
680, 660, 590 cm−1; 1H NMR (CDCl3): δ = 1.89 (d, J = 7.7 Hz, 9H, CH3), 2.43 (s, 3H,
CH3), 4.39 (s, 2H, CH2Te), 7.45−8.14 (m, 5H, arom-H); 13C NMR (CDCl3): δ = 18.6
(CH2Te), 27.0 (CH3), 34.8 C-CO), 126.9−142.3 (arom. ring), 195.3, 207.5 (C O).
Te -2,2-Dimethylpropanoylmethyl Benzenecarbotelluroate (2g)
Similarly to 2a, the reaction of potassium benzenecarbotelluroate (1.58 mmol) with
1-bromo-2-butanone (198 mg, 1.11 mmol) gave 330 mg (90%) of 2g as yellow liquid. IR
(KBr, neat): 3100, 2950, 1690 (C O), 1660 (C O), 1595, 1580, 1480, 1360, 1200, 990,
1
860, 760, 660, 610, 590 cm−1; H NMR (CDCl3): δ = 1.27 (s, 9H, CH3), 4.19 (s, 2H,
CH2Te), 7.45−7.73 (m, 5H, arom-H); 13C NMR (CDCl3): δ = 16.7 (CH2Te), 27.0 (CH3),
44.8 C-CO), 126.9, 129.1, 134.2, 142.6 (arom. ring), 195.6 (C O), 213.3 (C O); MS (CI):
m/z = 335, 333, 331 (M+1), 105 (C6H5CO).

938
S. NAKAIIDA ET AL.
Te -Phenacyl Benzenecarbotelluroate (2h)
Similarly to 2a, the reaction of freshly prepared potassium benzenexarbotelluroate
(1.96 mmol) with phenacyl bromide (273 mg, 1.37 mmol) gave 470 mg (97%) of 2h as
yellow oil. IR (neat): 3070, 1655 (C O), 1590, 1575, 1440, 1265, 1195, 1165, 995, 860,
750, 695, 670, 650, 580 cm−1; 1H NMR (CDCl3): δ = 4.55 (s, 2H, CH2Te), 7.35−8.03 (m,
10H, arom-H); 13C NMR (CDCl3): δ = 16.6 (CH2Te), 126.8−141.8 (arom. ring), 194.5
(C O), 197.5 (C O); MS (CI): m/z = 356, 352 (M+1), 105 (C6H5CO); HRMS: calcd for
C15H12O2Te: 353.9899; found: 353.9878.
Te -1-Methylphenacyl Benzenecarbotelluroate (2i)
Similarly to 2a, the reaction of potassium benzenecarbotelluroate (2.18 mmol) with
2-chloro-2-butanone (325 mg, 1.52 mmol) gave 450 mg (81%) of 2i as yellow liquid. IR
(KBr, neat): 3000, 2950, 1655 (C O), 1590, 1580, 1445, 1340, 1225, 1070, 860, 755, 705,
590 cm−1; 1H NMR (CDCl3): δ = 2.13, (3H, CH3), 5.29 (2H, CH2Te), 7.34−8.05 (m, 10H,
arom-H); 13C NMR (CDCl3): δ = 20.2 (CHTe), 29.8 (CH3), 126.8−141.9 (arom. ring),
195.3 (C O), 199.3 (C O); MS (CI): m/z = 368, 366, 364 (M+1), 105 (C6H5CO).
Te -4-Bromophenacyl Benzenecarbotelluroate (2j)
Similarly to 2a, the reaction of freshly prepared potassium benzenecarbotelluroate
(1.63 mmol) with 4-bromophenacyl bromide (362 mg, 1.30 mmol) gave a yellow solid.
Chromatographic separation on silica gel column [dichloromethane/hexane (1:1), Rf =
0.30, the second eluent] gave 480 mg (86%) of 2j as yellow crystals. M.p. 60−64◦C; IR
(neat): 3000, 1655 (C O), 1630, 1580, 1480, 1440, 1400, 1265, 1200, 1070, 1000, 870,
1
785, 760, 680, 665, 598 cm−1; H NMR (CDCl3): δ = 4.52 (s, 2H, CH2Te), 7.42−8.14
(m, 9H, arom-H); 13C NMR (CDCl3): δ = 16.3 (CH2Te), 127.0−141.9 (arom. ring), 194.7
(C O), 197.0 (C O).
Te -Ethoxycarbonylmethyl Benzenecarbotelluroate (2k)
Similarly to 2a, the reaction of potassium benzenecarbotelluroate (1.87 mmol) with
ethyl bromoacetate (218 mg, 1.31 mmol) and chromatographic separation on silica gel
column [dichloromethane/hexane (1:1), Rf = 0.33, the second eluent] gave 380 mg (90%)
of 2k as yellow liquid. IR (KBr, neat): 3000, 2950, 1715 (C O), 1660 (C O), 1580, 1445,
1245, 1090, 1030, 860, 760, 680, 660, 595 cm−1; 1H NMR (CDCl3): δ = 1.24 (t, J = 7.7
Hz, 3H, CH3), 3.81 (s, 2H, CH2Te), 4.16 (q, J = 7.7 Hz, 2H, CH2O), 7.42−7.73 (m, 5H,
arom-H); 13C NMR (CDCl3): δ = 9.2 (CH3), 13.9 (CH2Te), 61.3 (CH2O), 127.0, 129.1,
134.2, 142.1 (arom. ring), 172.8 (COO), 193.8 (COTe); MS (CI): m/z = 323, 321, 319
(M+1), 105 (C6H5CO).
Te -Aminocarbonylmethyl Benzenecarbotelluroate (2l)
Similarly to 2a, the reaction of potassium benzenecarbotelluroate (1.28 mmol) with
2-chloroacetoamide (82 mg, 0.90 mmol) gave 230 mg (88%) of 2l as yellow crystals. IR
(KBr, neat): 3460 (NH), 3350 (NH), 3250, 1660 (C O), 1640, 1615, 1175, 1160, 860, 770,
660, 590 cm−1; 1H NMR (CDCl3): δ = 3.63 (s, 2H, CH2Te), 5.71 (s, 1H, NH), 7.42−7.74

SYNTHESIS AND THERMOLYSIS OF TELLUROESTERS
939
(m, 5H, arom-H); 13C NMR (CDCl3): δ = 10.5 (CH2Te), 127.0, 129.3, 134.6, 142.3 (arom.
ring), 175.3 (CON), 198.4 (COTe); MS (CI): m/z = 294, 292, 290 (M+1), 105 (C6H5CO).
Te -Phenacyl 4-Methylbenzenecarbotelluroate (2m)
Similarly to 2a, the reaction of freshly prepared potassium 4-methylbenzene-
carbotelluroate (1.49 mmol) with phenacyl bromide (207 mg, 1.04 mmol) and chromato-
graphic separation on silica gel column [dichloromethane/hexane (1:1), Rf = 0.27, the
second eluent] gave 310 mg (81%) of 2m as yellow oil. IR (neat): 3000, 1660 (C O),
1
1635, 1580, 1450, 1310, 1270, 1205, 1170, 870, 780, 760, 610, 590 cm−1; H NMR
(CDCl3): δ = 2.37 (s, 3H, CH3), 4.56 (s, 2H, CH2Te), 7.23−8.05 (m, 9H, arom-H); 13C
NMR (CDCl3): δ = 16.4 (CH2Te), 21.8 (CH3), 127.2−145.6 (arom. ring), 193.9 (C O),
198.1 (C O); HRMS: calcd. for C11H12O2Te: 368.0056; found: 368.0048.
Te -4-Bromophenacyl 4-Methylbenzenecarbotelluroate (2n)
Similarly to 2a, the reaction of freshly prepared potassium benzenecarbotelluroate
(1.93 mmol) with 4-bromophenacyl bromide (536 mg, 1.93 mmol) and chromatographic
separation on silica gel column [dichloromethane/hexane (1:1), Rf = 0.35, the second elu-
ent] gave 590 mg (48%) of 2n as yellow crystals. Mp 73−78◦C; IR (KBr): 3000, 1660
(C O), 1630, 1590, 1580, 1560, 1390, 1300, 1260, 1195, 1170, 1140, 1060, 990, 870, 770,
600, 580 cm−1; 1H NMR (CDCl3): δ = 2.34 (s, 3H, CH3), 4.48 (s, 2H, CH2Te), 7.20−7.89
(m, 8H, arom-H); 13C NMR (CDCl3): δ = 16.0 (CH2Te), 21.7 (CH3), 127.1−145.6
(arom. ring), 193.5 (C O), 196.9 (C O); MS (CI): m/z = 447, 445, 443 (M+1), 119
(CH3C6H4CO).
Te -Phenacyl 2-Methoxybenzenecarbotelluroate (2o)
Similarly to 2a, the reaction of freshly prepared potassium 2-methoxybenzenecarbo-
telluroate (0.92 mmol) with phenacyl bromide (128 mg, 0.65 mmol) and chromatographic
separation on silica gel column [dichloromethane/hexane (1:1), Rf = 0.31, the second
eluent] gave 230 mg (93%) of 2o as yellow crystals. Mp 75−80◦C; IR (neat): 3000, 1660
1
(C O), 1630, 1480, 1280, 880, 770, 710 cm−1; H NMR (CDCl3): δ = 3.92 (s, 3H,
CH3O), 4.44 (s, 2H, CH2Te), 6.96−8.05 (m, 9H, arom-H); 13C NMR (CDCl3): δ = 27.2
(CH2Te), 55.2 (CH3O), 112.1, 121.1, 127.0, 128.4, 128.5, 128.8, 129.1, 132.9, 134.9, 159.6
(arom. ring), 195.0 (C O), 199.1 (C O); MS (CI): m/z = 384, 382, 380 (M+1), 1135
(CH3OC6H4CO). HRMS: calcd. for C15H12O2Te: 353.9899; found: 353.9878.
Te -Acetylmethyl 4-Methoxybenzenecarbotelluroate (2p)
Similarly to 2a, the reaction of potassium 4-methoxybenzenecarbotelluroate (1.37
mmol) with chloroacetone (88 mg, 0.96 mmol) gave 240 mg (78%) of 2p as yellow liquid.
IR (KBr, neat): 3100, 2950, 1660 (C O), 1630, 1570, 1410, 1350, 1260, 1210, 1160,
1175, 1160, 860, 770, 660, 590 cm−1; 1H NMR (CDCl3): δ = 2.37 (s, 3H, CH3), 3.87 (s,
3H, CH3O), 3.92 (s, 2H, CH2Te), 6.92−7.71 (m, 4H, arom-H); 13C NMR (CDCl3): δ =
20.0 (CH2Te), 27.6 (CH3), 55.6 (CH3O), 114.2−164.5 (arom. ring), 191.1 (COMe), 206.3

940
S. NAKAIIDA ET AL.
(COTe); MS (CI): m/z = 325, 323, 321 (M+1), 135 (CH3C6H4CO); HRMS calcd. for
C11H12O3Te: 321.9848; found: 321.9864.
Te -4-Bromophenacyl 4-Methoxybenzenecarbotelluroate (2q)
Similarly to 2a, the reaction of freshly prepared potassium 4-methoxybenzenecarbo-
telluroate (1.33 mmol) with 4-bromophenacyl bromide (258 mg, 0.93 mmol) and chro-
matographic separation on silica gel column [dichloromethane/hexane (1:1), Rf = 0.50,
the second eluent] gave 160 mg (62%) of 2q as yellow solid. Mp 93−96◦C (yellow crys-
tals); IR (neat): 3000, 1660 (C O), 1635, 1595, 1580, 1570, 1505, 1260, 1170, 1030,
1
995, 880, 780, 610, 595 cm−1; H NMR (CDCl3): δ = 3.84 (s, 3H, CH3O), 4.48 (s, 2H,
CH2Te), 6.90−7.90 (m, 8H, arom-H); 13C NMR (CDCl3): δ = 15.9 (CH2Te), 55.6 (CH3O),
114.0−164.7 (arom. ring), 191.5 (C O), 197.1 (C O); Anal: calcd. for C16H13O3BrTe:
C 41.71, H 2.84; Found: C 40.63, H 2.83.
Thermolysis of Te -α-Ketoalkyl Carbotelluroates (2) Leading to Vinyl
Esters (4)
1-4-Bromophenylethenyl propanoate (4a). Te-4-bromophenacyl ethanecar-
botelluroate 2a (200 mg, 0.52 mmol) was heated under argon atmosphere at 80◦C for
3 h. Ether (50 mL) was added, and the precipitate (black tellurium) was separated by fil-
tration. Removal of the solvent and chromatography of the residue on silica gel column
[dichloromethane/hexane (1:1), Rf = 0.43, the first eluent] gave 60 mg (45%) of 4a as
colorless oil. IR (KBr, neat): 3000, 2950, 1755 (C O), 1640, 1585, 1485, 1250, 1140,
1
1090, 1005, 890, 830 cm−1; H NMR (CDCl3): δ = 1.24 (t, J = 7.3 Hz, 3H, CH3), 2.54
(q, J = 7.3 Hz, 2H, CH2), 5.04 (d, J = 7.3 Hz, 1H, CH = C), 5.44 (d, J = 2.2 Hz, 1H,
CH = C), 7.30−7.48 (m, 4H, arom-H); 13C NMR (CDCl3): δ = 9.0 (CH3), 27.7 (CH2),
102 (C C), 123.0, 126.5, 131.7, 133.6, 152.2 (arom. ring), 172.4 (C O); MS (CI): m/z =
256, 254 (M+1); HRMS: calcd. for C11H11O2Br: 253.9942; found: 253.9919.
3,3-Dimethyl-1-butenyl 1-methylbutanoate (4b). Similarly to 4a, heating
of Te-2,2-dimethylpropanoylmethyl 1-methylethanecarbo-telluroate 2b (240 mg, 0.80
mmol) at 50−60◦C for 3 h, and chromatographic separation on silica gel column
[dichloromethane/hexane (1:1), Rf = 0.45, the first eluent] gave 40 mg (30%) of 4b as
colorless oil. IR (KBr, neat): 3010, 2930, 1750 (C O), 1650, 1470, 1390, 1365, 1130,
1060, 1020, 880 cm−1; 1H NMR (CDCl3): δ = 1.10 (s, 9H, CH3), 1.24 (d, J = 7.0 Hz, 6H,
CH3), 2.66 (1H, CH3), 4.61 (d, J = 1.8 Hz, 1H, CH C), 4.85 (d, J = 1.8 Hz, 1H, CH C);
13C NMR (CDCl3): δ = 19.2 (CH3), 27.8 (CH3), 34.5 (CH), 36.2 (CCO), 98.6 (C C),
162.6 (C C), 175.1 (C O); MS (CI): m/z = 171 (M+1); HRMS: calcd. for C10H18O2:
170.1307; found: 170.1301.
1-Phenylethenyl 1-methylbutanoate (4c). Similarly to 4a, heating of Te-
phenacyl 1-methylethanecarbotelluroate 2c (250 mg, 0.78 mmol) at 80−90◦C for 5 h,
and chromatographic separation on silica gel column [dichloromethane/hexane (1:1), Rf =
0.23, the first eluent] gave 60 mg (40%) of 4c as colorless oil. IR (KBr, neat): 3000, 1745
(C O), 1630, 1495, 1470, 1265, 1130, 760, 690 cm−1; 1H NMR (CDCl3): δ = 1.30 (6H,
CH3), 2.79 (1H, CH), 5.00 (d, J = 2.2 Hz, 1H, CH C), 5.45 (d, J = 2.2 Hz, 1H, CH C),
7.25−7.48 (m, 5H, arom-H); 13C NMR (CDCl3): δ = 19.0 (CH3), 34.2 (CH), 101.9 (C C),

SYNTHESIS AND THERMOLYSIS OF TELLUROESTERS
941
124.9, 128.5, 134.6, 153.1 (arom. ring), 175.1 (C O); MS (CI): m/z = 190 (M+1), 105
(CH2 = CC6H5); HRMS: calcd. for C12H14O2: 190.0993; found: 190.1008.
1-Phenyl-1-methylethenyl 1-methylpropanoate (4d). Similarly to 4a, heat-
ing of Te-1-methylphenacyl 1-methylethanecarbotelluroate 2d (170 mg, 0.51 mmol) at
80−100◦C for 5 h and chromatography on silica gel column [dichloromethane/hexane
(1:1), Rf = 0.50, the first eluent] gave 50 mg (42%) of 1-(phenyl)-1-methylethenyl 1-
methylpropanoate 4d (E/Z = 6:94) as colorless oil. IR (KBr, neat): 3000, 1745 (C O),
1460, 1440, 1230, 1130, 1060, 745, 680 cm−1; 1H NMR (CDCl3): Z-4d: δ = 1.34 (d, J =
7.0 Hz, 3H, CH3), 1.69 (d, J = 7.3 Hz, 3H, CH3C C), 2.83 (m, 1H, CH), 5.87 (q, J = 7.0
Hz, 1H, CH C), 7.28−7.40 (m, 5H, arom-H); E-4d: δ = 1.21 (d, J = 7.0 Hz, 3H, CH3),
1.82 (d, J = 7.3 Hz, 3H, CH3C C), 3.03 (m, 1H, CH), 5.52 (q, J = 7.0 Hz, 1H, CH C),
7.27−7.40 (m, 5H, arom-H); 13C NMR (CDCl3): δ = 11.5 (CH3), 19.2 (CH3), 34.2 (CH),
112.5, 124.3, 128.0, 128.5, 135.3, 146.9 (arom. ring), 158.2 (C C), 174.6 (C O); MS
(CI): m/z = 205 (M+1); HRMS: calcd. for C13H16O2: 192.1150; found: 192.1144.
1-4ꢀ-Bromopheny-)ethenyl 1-pentanoate (4e). Similarly to 4a, heating of Te-
4-bromophenacyl 1-butanecarbotelluroate 2d (220 mg, 0.50 mmol) at 80−90◦C for 3 h.
Chromatographic separation on silica gel column [dichloromethane/hexane (1:1), Rf =
0.43, the first eluent] gave 50 mg (36%) of 4e as colorless oil and 30 mg (8%) of 4-
bromoacetophenone 9g as colorless crystals. 4e: IR (KBr, neat): 3000, 1750 (C O), 1640,
1595, 1495, 1480, 1255, 1225, 1140, 1090, 1010, 830 cm−1; 1H NMR (CDCl3): δ = 0.95
(t, J = 7.3 Hz, 3H, CH3), 1.40 (m, 2H, CH2), 1.70 (m, 2H, CH2), 2.53 (t, J = 7.3 Hz, 2H,
CH2CO), 5.03 (d, J = 2.2 Hz, 1H, CH C), 5.43 (d, J = 2.2 Hz, 1H, CH C), 7.30−7.48 (m,
4H, arom-H); 13C NMR (CDCl3): δ = 13.7 (CH3), 22.3, 26.9, 34.0 (CH2), 102.6 (C C),
123.0, 126.5, 131.7, 133.6, 152.6 (arom. ring), 171.7 (C O); MS (CI): m/z = 285, 283
(M+1), 85 (C4H9CO); HRMS: calcd. for C13H17BrO2: 284.04119; found: 284.04107. 9g:
M.p. 50−52◦C. The IR of 9g was consistent with that of the authentic sample.
1-Ethyl-ethenyl Benzoate (4f) and 1-Methyl-1-propenyl Benzoate (6)
Similarly to 4a, heating of Te-propanoylmethyl benzenecarbotelluroate 2f (330
mg, 0.50 mmol) at 90−100◦C for 5 h and chromatography on silica gel column
[dichloromethane/hexane (1:1), Rf = 0.43, the first eluent] gave 80 mg (45%) of a mixture
of 4f and 6 (E/Z = 30:70) (4f/6 = 60:40) as colorless oil. IR (KBr, neat): 3000, 2950,
1720 (C O), 1600, 1450, 1260, 1175, 1110, 1070, 1030, 710 cm−1; 4f: 1H NMR (CDCl3):
δ = 1.13 (t, J = 7.7 Hz, 3H, CH3), 2.35 (q, J = 7.7 Hz, 2H, CH2), 4.83 (d, J = 7.3 Hz,
CH C), 4.85 (d, J = 7.3 Hz, 1H, CH C), 7.44−8.13 (m, 4H, arom-H). 6 (E/Z): δ = 1.53
(d, J = 1.5 Hz, 3H, CH3), 1.69 (q, J = 6.6 Hz, 3H, CH3), 1.98 (q, J = 1.5 Hz, 3H, CH3),
5.15 (d, J = 1.5 Hz, 1H, CH C), 5.29 (q, J = 5.5 Hz, 1H, CH C), 7.44−8.13 (m, 4H,
arom-H); 13C NMR (CDCl3): δ = 10.7, 11.1, 19.5, 26.6 (CH2, CH3), 100.4−145.8 (C =
C, arom. ring), 158.2 (C = C), 164.8 (C O); MS (CI): m/z = 176 (M+1), 105 (C6H5CO);
HRMS: calcd. for C11H11O2: 176.08373; found: 176.08354.
3,3-Dimethyl-1-butenyl Benzoate (4g)
Similarly to 4a, heating of Te-2,2-dimethylpropanoylmethyl benzenecarbotelluroate
2g (280 mg, 0.84 mmol) at 150−160◦C for 5 h and chromatography on silica gel column
[dichloromethane/hexane (1:1), Rf = 0.60, the first eluent] gave 40 mg (32%) of 4g as
colorless oil. IR (KBr, neat): 3000, 2900, 1730 (C O), 1650, 1600, 1450, 1280, 1260,

942
S. NAKAIIDA ET AL.
1140, 1020, 890, 830, 700 cm−1; 1H NMR (CDCl3): δ = 1.19 (s, 3H, CH3), 4.81 (d, J =
2.2 Hz, 1H, CH C), 4.99 (d, J = 2.2 Hz, 1H, CH C), 7.48−8.12 (m, 5H, arom-H); 13
C
NMR (CDCl3): δ = 28.0 (CH3), 36.5 (C-CO), 92.2 (C = C), 128.5, 130.0, 130.2, 133.2,
162.8 (arom. ring), 164.8 (C O); MS (CI): m/z = 205 (M+1), 105 (C6H5CO); HRMS:
calcd. for C13H16O2: 204.1151; found: 204.1148.
1-Phenylethenyl Benzoate (4h)
Similarly to 4a, heating of Te-phenacyl benzenecarbotelluroate 2h (350 mg,
0.91 mmol) at 100−110◦C for 5 h and chromatography on silica gel column
[dichloromethane/hexane (1:1), Rf = 0.38, the first eluent] gave 40 mg (32%) of
4h as colorless oil and 15 mg (10%) of benzoic anhydride 5a colorless solid. 4h: IR
(KBr, neat): 3000, 2950, 1730 (C O), 1640, 1600, 1490, 1450, 1240, 1100, 1070, 1030,
1
890, 830, 790, 710 cm−1; H NMR (CDCl3): δ = 5.16 (d, J = 2.2 Hz, 1H, CH C),
5.59 (d, J = 2.2 Hz, 1H, CH C), 7.24−8.12 (m, 10H, arom-H); 13C NMR (CDCl3): δ
= 12.3, 25.0−153.3 (C C, arom. ring), 164.8 (C O); MS (CI): m/z = 225 (M+1), 105
(C6H5CO); HRMS calcd. for C15H12O2: 224.0832; found: 224.0816. 5a: M.p. 39−41◦C.
The IR spectrum of 5a was consistent with that of an authentic sample.
1-(4-Bromophenyl)ethenyl Benzoate (4i)
Similarly to 4a, heating of Te-4-bromophenacyl benzenecarbotelluroate 2j (260
mg, 0.30 mmol) at 90−100◦C for 5 h and chromatography on silica gel column
[dichloromethane/hexane (1:1), Rf = 0.44, the first eluent] gave 500 mg (34%) of 4i as
colorless oil. IR (KBr, neat): 3000, 2950, 1730 (C O), 1640, 1590, 1480, 1450, 1240,
1170, 1090, 1060, 1020, 1010, 830, 760, 710 cm−1; 1H NMR (CDCl3): δ = 5.20 (d, J =
2.2 Hz, 1H, CH C), 5.58 (d, J = 2.2 Hz, 1H, CH C), 7.26−8.15 (m, 9H, arom-H); MS
(CI): m/z = 305, 303 (M+1), 185, 183 (CH2 CC6H4Br); HRMS calcd. for C15H11O2Br:
301.9942; found: 301.9928.
1-Phenyl-1-propenyl Benzoate (4j)
Similarly to 4a, heating of Te-1-methylphenacyl benzenecarbotelluroate 2i (450
mg, 1.22 mmol) at 90−100◦C for 5 h and chromatography on silica gel column
[dichloromethane/hexane (1:1), Rf = 0.57, the first eluent] gave 50 mg (40%) of 4j (E/Z =
5:95) as colorless oil. IR (KBr, neat): 3100, 2950, 1725 (C O), 1595, 1495, 1450, 1420,
1175, 1090, 1065, 1025, 750, 705 cm−1; 1H NMR (CDCl3): (Z)-4l: δ = 1.76 (d, J = 7.0
Hz, 3H, CH3), 6.01 (q, J = 7.0 Hz, 1H, CH C), 7.26−8.25 (m, 10H, arom-H); (E)-4j: δ
= 1.88 (d, J = 7.0 Hz, 3H, CH3), 5.68 (q, J = 7.0 Hz, 1H, CH C), 7.26−8.25 (m, 10H,
arom-H); 13C NMR (CDCl3) δ = 11.7 (CH3), 112.9, 124.4, 128.1, 128.7, 129.4, 130.2,
133.6, 135.1, 147.1 (C C), 158.2 (C C, arom. ring), 164.3 (C O); MS (CI): m/z = 239
(M+1), 105 (C6H5CO); HRMS: calcd. for C16H14O2: 238.09938; found: 238.09926.
1-(4-Bromophenyl)ethenyl 4-Methylbenzoate (4k)
Similarly to 4a, heating of Te-phenacyl 4-methylbenzenecarbotelluroate 2m
(670 mg, 1.50 mmol) at 90−100◦C for 6 h and chromatography on silica gel column

SYNTHESIS AND THERMOLYSIS OF TELLUROESTERS
943
[dichloromethane/hexane (1:1), Rf = 0.37, the first eluent] gave 153 mg (32%) of 4k as
colorless crystals. IR (KBr, neat): 3000, 2950, 1720 (C O), 1640, 1600, 1580, 1470, 1240,
1170, 1040, 1000, 880, 840, 740 cm−1; 1H NMR (CDCl3): δ = 2.43 (s, 3H, CH3), 5.17 (d,
J = 2.2 Hz, 1H, CH C), 5.56 (d, J = 2.2 Hz, 1H, CH C), 7.28−8.07 (m, 9H, arom-H);
MS (CI): m/z = 318, 316 (M+1), 119 (CH3C6H4CO); HRMS calcd. for C16H13O3Br:
316.00989; found: 316.0076.
1-(4-Bromophenyl)ethenyl 4-Methoxybenzoate (4l)
Similarly to 4a, heating of Te-4-bromophenacyl 4-methoxybenzenecarbotelluroate
2q (220 mg, 0.47 mmol) at 100−110◦C for 5 h and chromatography on silica gel column
[dichloromethane/hexane (1:1), Rf = 0.33, the first eluent] gave 40 mg (20%) of 4l as
colorless oil. IR (KBr, neat): 3000, 1720 (C O), 1680, 1610, 1590, 1510, 1400, 1260,
1240, 1170, 1090, 1010, 830, 760 cm−1; 1H NMR (CDCl3): δ = 3.96 (s, 3H, CH3O), 5.19
(d, J = 2.2 Hz, 1H, CH C), 5.55 (d, J = 2.2 Hz, 1H, CH C), 6.90−8.20 (m, 8H, arom-H);
MS (CI): m/z = 335, 333 (M+1), 135 (CH3OC6H4CO); HRMS calcd for C16H13O3Br:
332.0048; found: 332.0046; Anal calcd. for C16H13O3Br: C, 60.59, H, 4.13; found: C,
60.95, H, 4.44.
Treatment of Te -α-Ketoalkyl Carbotelluroates (2) with Potassium
tert-Butanolate Leading to 1,3-Diketone (7)
1-Phenyl-1,3-butanedione (7a). tert-Butanol (20mL) containingpotassium tert-
butanolate (50 mg, 0.5 mmol) was added to Te-acetylmethyl benezenecarbotelluroate 2d
(100 mg, 0.5 mmol). The mixture was stirred at 20◦C for 3 h under argon atmosphere and
then ether (50 mL) was added. The insoluble part (black) was filtered, and the solvent was
removed under reduced pressure. Chromatography of the resulting precipitate on silca gel
[dichloromethane/hexane (1:1), Rf = 0.41, the first eluent] gave 25 mg (45%) of 7a as
colorless crystals. Mp 59−60◦C (Lit; 57−59◦C[2], Lit; 60−61◦C[9]); IR (KBr, neat): 3000,
2950, 1700 (C O), 1660 (C O), 1260, 1020, 840, 760, 695 cm−1; 1H NMR (CDCl3): δ
= 2.20 (s, 3H, CH3), 6.18 (s, 1H, CH C), 7.45−7.89 (m, 5H, arom-H); MS (CI): m/z =
162 (M+1), 105 (C6H5CO); HRMS: calcd. for C10H10O2: 162.0680; found: 162.0660.
1,3-Diphenyl-1,3-propanedione (7b). Similarly to 7a, the reaction of Te-
phenacyl benzenecarbotelluroate 2h (150 mg, 1.33 mmol) with tert-butanolate (50
mg, 0.50 mmol), followed by separation using silica gel column chromatography
[dichloromethane/hexane (1:1)], gave 50 mg (35%) of 7b (Rf = 0.45, the first eluent)
and 25 mg (45%) of acetophenone 9b (Rf = 0.21, the second eluent) as colorless oil,
respectively. 7b: Mp 75−77◦C (Lit; 75−78◦C[10]); IR (KBr, neat): 3100, 2950, 1595
1
(C O), 1310, 1230, 1000, 740, 680, 605 cm−1; H NMR (CDCl3): δ = 6.84 (s, 1H,
CH C), 7.44−7.99 (m, 10H, arom-H), 16.87 (s, 1H, OH); 13C NMR (CDCl3): δ = 93.2
(CH2), 127.2, 128.7, 132.4, 135.6 (arom-C), 185.8 (C O); MS (CI): m/z = 223 (M+1),
105 (C6H5CO; HRMS: calcd for C15H12O2: 224.0837; found: 224.0839. 9b: M.p. 20◦C.
The m.p. and IR spectrum of 9b were consistent with those of an authentic sample.
1-(4ꢀ-Methylphenyl)-3-phenyl-1,3-propanedione (7c). Similarly to 7a, the
reaction of Te-phenacyl 4-methylbenzenecarbotelluroate 2m (310 mg, 1.33 mmol) with
tert-butanolate (70 mg, 0.62 mmol), followed by separation using silica gel column chro-
matography [dichloromethane/hexane (1:1), Rf = 0.40, the first eluent], gave 20 mg (26%)
of 7c as colorless crystals: Mp 86−89◦C. IR (KBr, neat): 3100, 2950, 1600 (C O), 1540,

944
S. NAKAIIDA ET AL.
1
1530, 1480, 1300, 1230, 1180, 810, 765, 695, 680 cm−1; H NMR (CDCl3): δ = 2.43
(s, 3H, CH3), 6.83 (s, 1H, CH C), 7.25−7.99 (m, 9H, arom-H), 16.91 (s, 1H, OH); 13C
NMR (CDCl3): δ = 21.7 (CH3), 92.9 (CH2), 127.1−143.3 (arom-C), 185.2 (C O), 186.1
(C O); MS (CI): m/z = 239 (M+1), 119 (CH3C6H4CO); HRMS: calcd for C15H12O2:
224.0837; found: 224.0834.
1-(4-Bromophenyl-3-(4-methyl)phenyl-1,3-propanedione (7d). Similarly
to 7a, the reaction of Te-4-bromophenacyl 4-methylbenzenecarbotelluroate 2n (1010 mg,
2.27 mmol) with tert-butanolate (254 mg, 2.27 mmol), followed by separation using silica
gel column chromatography [dichloromethane/hexane (1:1)], gave 66 mg (23%) of 7d
(Rf = 0.35, the first eluent) and 30 mg (15%) of 4-bromoacetophenone 9g (Rf = 0.10, the
third eluent) as colorless crystals, respectively. 7d: Mp 162−165◦C; IR (KBr, neat): 3100,
1
2950, 1600 (C O), 1580, 1480, 1300, 1225, 1210, 1070, 1010, 840, 780, 490 cm−1; H
NMR (CDCl3): δ = 2.43 (s, 3H, CH3), 6.77 (s, 1H, CH C), 7.27−7.89 (m, 8H, arom-H),
16.85 (s, 1H, OH); 13C NMR (CDCl3): δ = 21.7 (CH3), 92.7 (CH2), 127.1−143.5 (arom.
ring), 184.0 C = O), 186.2 (C O); MS (CI): m/z = 319, 317 (M+1), 119 (CH3C6H4CO);
HRMS: calcd. for C16H13O2Br: 316.0098; found: 316.0081. 9g: M.p. 50−52◦C (Lit.
54◦C[11]). The mp and IR spectrum of 9g were consistent with those of an authentic sample.
1-(4ꢀ-Methoxy)phenyl-1,3-butanedione (7e). Similarly to 7a, the reaction of
Te-acetylmethyl 4-methoxybenzenecarbotelluroate 2p (240 mg, 0.75 mmol) with tert-
butanolate (84 mg, 0.75 mmol), followed by separation using silica gel column chro-
matography [dichloromethane/hexane (1:1)], gave 7e (Rf = 0.52, the first eluent) and 40
mg (35%) of 4-methoxybenzoic acid 8 (R = 4-MeC6H4) (Rf = 0.31, the second eluent)
as colorless crystals, respectively. 7e: Mp 48−51◦C; IR (KBr, neat): 3100, 2950, 1600
(C O), 1260, 1180, 1020, 845, 770 cm−1; 1H NMR (CDCl3): δ = 2.17 (s, 3H, CH3), 3.86
(s, 3H, CH3O), 6.12 (s, 1H, CH C), 6.92−7.88 (m, 4H, arom-H), 16.32 (s, 1H, OH);
13C NMR (CDCl3): δ = 25.3 (CH3), 55.3 (CH3O), 95.8 (CH2), 113.9, 127.6, 129.1, 163.1
(arom. ring), 189.2 (C O), 191.6 (C O); HRMS: calcd. for C11H12O3: 192.0786; found:
192.0778. 8 (R = 4-MeOC6H4): M.p. 181−184◦C (Lit. 182−185◦C[12]). The mp and IR
spectrum of 8 (R = 4-MeC6H4) were consistent with those of an authentic sample.
1-(4-Bromophenyl)-3-(4-methoxyphenyl)-1,3-propanedione (7f). Simi-
larly to 7a, the reaction of Te-4-bromophenacyl 4-methoxybenzenecarbotelluroate 2q
(763 mg, 1.66 mmol) with tert-butanolate (186 mg, 1.66 mmol), followed by separation
using silica gel column chromatography [dichloromethane/hexane (1:1)], gave 50 mg
(36%) of 7f (Rf = 0.35, the second eluent) and 30 mg (20%) of 4-methoxybenzoic acid 8
(R = 4-MeOC6H4) (Rf = 0.02, the third eluent) as colorless crystals, respectively. 7f: Mp
150−153◦C; IR (KBr, neat): 3100, 2950, 1600 (C O), 1580, 1300, 1230, 1170, 1065,
1
1020, 1000, 840, 780 cm−1; H NMR (CDCl3): δ = 3.89 (s, 3H, CH3O), 6.74 (s, 1H,
CH C), 6.97−7.98 (m, 4H, arom-H), 16.96 (s, 1H, OH); 13C NMR (CDCl3): δ = 25.3
(CH3), 55.3 (CH3O), 95.8 (CH2), 113.9, 127.6, 129.1, 163.1 (arom. ring), 189.2 (C O),
191.6 (C O); MS (CI): m/z = 335, 333 (M+1), 135 (CH3C6H4CO); HRMS: calcd. for
C16H13BrO2: 332.00481; found: 332.00446. 8 (R = 4-MeOC6H4): M.p. 181−184◦C (Lit.
182−185◦C[12]), the m.p. and IR spectrum were consistent with those of an authentic
sample.

SYNTHESIS AND THERMOLYSIS OF TELLUROESTERS
945
Typical Procedures for the Reaction of Potassium
Benzenecarbotelluroates (1) (R = Phenyl) with α-Haloketo Oximes (12)
Leading to Te -α-Iminopropyl Carbotelluroates (13) or O-Acylacetophenone
Oximes (14)
O-Acetyl acetone oxime (14a). A solution of chloroacetone oxime 12a (120 mg,
1.11 mmol) in acetonitrile (5 mL) was added to the freshly prepared potassium methanecar-
botelluroate (0.75 mmol) in tetrahydrofuran (5 mL) at –20◦C under argon atmosphere. The
mixture was stirred at this temperature for 1 h; the pink color of the potassium salt quickly
changed to pale yellow. Filtration of the precipitate and removal of the solvent under reduced
pressure at 0 to –5◦C gave 190 mg of yellow oil (71% as syn/anti-Te-2-hydroxyiminopropyl
methanecarbotelluroate 13a (black tellurium quickly liberates at room temperature). Chro-
matography of this yellow oil on silica gel column [dichloromethane/hexane (2:1), Rf =
0.60, the first eluent] gave 80 mg (63%) of O-acetyl acetone oxime 14a (syn/anti = 90:10)
as colorless liquid. IR (KBr, neat): 2960, 2850, 1750 (C O), 1370 (C O), 1280, 1210,
1010, 940, 600 cm−1; 1H NMR (CDCl3): δ = 2.01 (s, 3H, CH3), 2.04 (s, 3H, CH3), 3.16 (s,
3H, CH3O); 13C NMR (CDCl3): δ = 16.7 (CH3), 19.2 (CH3O), 21.7 (CH3), 163.6 (C = N),
168.6 (C O); MS (CI): m/z = 102 (M+1), 105 (C6H5CO); HRMS: calcd. for C4H7NO2:
101.04768; found: 101.04768.
O-Benzoyl acetone oxime (14b). Similarly to 14a, the reaction of potassium
benzenecarbotelluroates (2.06 mmol) with α-bromoacetophenone oxime 12b (155 mg,
1.44 mmol) gave 310 mg of yellow oil (71% as Te-2-hydroxyiminoacetophenone ben-
zenecarbotelluroate 13b; the yellow changed to colorless with liberation of black tel-
lurium. Dichloromethane (5 mL) was added. Filtration of the precipitate, removal of the
solvent, and chromatographic separation of the resulting residue on silica gel column
(dichloromethane/hexane = 2:1, Rf = 0.51, the second eluent) gave 92 mg (60%) of O-
benzoyl acetone oxime 14b (syn/anti = 95:5) as colorless liquid: IR (KBr, neat): 3010,
1
1735 (C O), 1600, 1450, 1375, 1280, 1250, 1090, 1060, 1030, 910, 820, 805 cm−1; H
NMR (CDCl3): δ = 2.12 (s, 3H, CH3), 2.13 (s, 3H, CH3), 7.43−8.08 (m, 5H, arom-H);
13C NMR (CDCl3): δ = 16.9 (CH3), 21.9 (CH3), 128.4, 129.2, 129.4, 133.1 (arom. ring),
163.8 (C = N), 164.5 (C O); MS (CI): m/z = 164 (M+1), 105 (C6H5CO); HRMS: calcd.
for C9H9NO2: 163.06333; found: 163.06325.
O-Benzoyl acetophenone oxime (14c). Similarly to 14a, the reaction of potas-
sium benzenecarbotelluroates (1.31 mmol) with α-bromoacetophenone oxime 12c (196
mg, 0.92 mmol) in acetonitrile (15 mL) gave 300 mg of yellow crystals (89%) as Te-
acetophenone oxime benzenecarbotelluroate 13c. Ether (50 mL) was added. Filtration of
the insoluble precipitate (black), removal of the solvent, and chromatographic separation
of the resulting residue on silica gel column (dichloromethane/hexane = 2:1, Rf = 0.52,
the second eluent) gave 120 mg (55%) of O-benzoyl acetophenone oxime 14c (syn/anti =
82:18) as colorless crystals. M.p 95−98◦C; IR (KBr, neat): 3000, 1730 (C O), 1440, 1310,
1230, 1050, 1010, 900, 755, 690 cm−1; 1H NMR (CDCl3): δ = 2.45 (anti) / 2.13 (syn) (s,
3H, CH3), 7.33−8.12 (m, 10H, arom-H); 13C NMR (CDCl3): δ = 14.6 (CH3), 127.1, 134.8
(arom. ring), 163.6 (C = N), 163.7 (C O); MS (CI): m/z = 226 (M+1), 105 (C6H5CO);
HRMS: calcd. for C14H11NO2: 225.07898; found: 225.07876.
O-Benzoyl 4-bromoacetophenone oxime (14d). Similarly to 14c, the reaction
of potassium benzenecarbotelluroates (2.31 mmol) with α-4ꢁ-dibromoacetophenone oxime
12d (473 mg, 1.62 mmol) gave 720 mg of yellow crystals (70−75◦C, 98%) as Te-4-
bromoacetophenone oxime benzenecarbotelluroate 13d. Upon exposure to air, the yellow

946
S. NAKAIIDA ET AL.
color quickly disappeared with liberation of black tellurium. Chromatographic separation
of the resulting residue on silica gel column (dichloromethane/hexane = 2:1, Rf = 0.50,
the second eluent) gave 280 mg (65%) of O-benzoyl 4-bromoacetophenone oxime (14d)
(syn/anti = 95:5) as colorless crystals. Mp 118−120◦C; IR (KBr): 3000, 1730 (C O),
1310, 1250, 1055, 920, 820, 690, 545 cm−1; 1H NMR (CDCl3): δ = 2.45 (anti), 2.52 (syn)
(s, 3H, CH3), 7.42−8.11 (m, arom-H); 13C NMR (CDCl3): δ = (syn/anti = 95 : 5) 14.1
(CH3), 61.3 (CH3O), 125.0−133.5 (arom. ring), 162.3 (C = N), 163.4 (C O); MS (CI):
m/z = 306, 305 (M+1), 105 (C6H5CO); HRMS: calcd. for C14H10BrNO2: 302.989494;
found: 302.98465.
Te -2-Methoxyiminopropyl benzenecarbotelluroate (13e). A solution of
freshely prepared potassium benzenecarbotelluroate (1.54 mmol) in THF (5 mL) was
added to chloro-O-methoxyacetone oxime 12e (131 mg, 1.08 mmol) in acetonitrile (5 mL)
at –20◦C, and the reaction mixture was stirred for 1 h; the red color of the potassium salt
changed to pale yellow within 10 min. The insoluble parts (black Te, excess of K(PhCOTe),
KCl) were separated by filtration. Removal of the solvent under reduced pressure gave 300
mg (87%) of Te-2-methoxyiminopropyl benzenecarbotelluroate 13e (anti/syn = 90:10) as
yellow oil. IR (KBr, neat): 2960, 2850, 1715 (C O), 1660 (C O), 1575, 1440, 1360, 1200,
1
1170, 1050, 910, 860, 835, 755, 680, 660, 590 cm−1; H NMR (CDCl3): anti-13e: δ =
1.98 (s, 3H, CH3), 3.86 (s, 3H, CH3O), 3.73 (s, 2H, CH2Te); syn-13e: δ = 2.03 (s, 3H,
CH3), 3.83 (s, 3H, CH3O), 3.91 (s, 2H, CH2Te), 7.40−7.74 (m, 5H, arom-H); 13C NMR
(CDCl3): δ = 4.4, 15.1, 19.2 (CH2, CH3), 126.7, 128.3, 129.2, 129.4, 142.5 (arom. ring),
156.5 (C N), 195.6 (C O); MS (CI): m/z = 320, 318, 316 (M+1), 105 (C6H5CO). The
IR spectrum was consistent with that of an authentic sample, which was prepared from the
reaction of sodium benezenecarbotelluroate with chloro-O-methoxyacetone oxime.
REFERENCES
1. M. Roth, P. Dubs, E. Go¨tschi, and A. Eschenmoser, Helv. Chim. Acta, 54, 710 (1971).
2. H. Ishihara and Y. Hirabayashi, Chem. Lett., 1007 (1978).
3. (a) T. Kakigano, T. Kanda, M. Ishidai, and S. Kato, Chem. Lett., 475 (1987); (b) T. Kanda,
S. Nakaiida, T. Murai, and S. Kato, Tetrahedron Lett., 30, 1829 (1989); (c) S. Kato, O. Niyomura,
S. Nakaiida, Y. Kawahara, T. Kanda, R. Yamada, and S. Hori, Inorg. Chem., 38, 519 (1999).
4. (a) A. Ogawa and N. Sonoda, In Comprehensive Organic Functional Group Transformations,
C. J. Moody, ed. (Elsevier Science, New York, 1995), Vol. 5, pp. 231–255; (b) A. Ishii and
Nakayama, In Comprehensive Organic Functional Group Transformations, C. J. Moody, ed.
(Elsevier Science, New York, 1995), Vol. 5, pp. 505–543; (c) S. Kato, T. Murai, and M. Ishida,
Org. Prep. Proceds. Int., 18, 369 (1986); (d) S. Kato and O. Niyomura, Top. Curr. Chem., 251,
13 (2005).
5. M. Ishida, H. Nakanishi, and S. Kato, Phosphorus and Sulfur, 22, 135 (1985).
6. G. L. Karabatsos, R. A. Taller, and F. M. Vane, J. Am. Chem. Soc., 85, 2326 (1963).
7. R. B. Wagner and H. D. Zook, Synthetic Organic Chemistry (Wiley, New York, 1961).
8. S. E. Denmark, M. S. Dappen, N. L. Sear, and R. T. Jacobs, J. Am. Chem. Soc., 112, 3466 (1990).
9. F. W. Swamed and C. R. Hauser, J. Am. Chem. Soc., 72, 1352 (1950).
10. C. F. H. Allen, R. D. Abell, and J. B. Normington, Org. Synth., Coll. Vol. I, 205 (1967).
11. R. Adams and C. R. Noller, Org. Synth., Coll. Vol. 1, 10 (1941).
12. H. Gross, J. Rusche, and M. Mirsch, Chem. Ber., 96, 1382 (1963).