Specific intramolecular aromatic C–H insertion of diazosulfonamides

Article abstract of DOI:10.1016/j.tet.2017.04.056

The chemoselectivity in the intramolecular C–H insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while t

Full text of DOI:10.1016/j.tet.2017.04.056

Accepted Manuscript
Specific intramolecular aromatic C-H insertion of diazosulfonamides
Peipei Huang, Zhanhui Yang, Jiaxi Xu
PII:
S0040-4020(17)30448-9
10.1016/j.tet.2017.04.056
TET 28657
DOI:
Reference:
To appear in: Tetrahedron
Received Date: 19 March 2017
Revised Date: 19 April 2017
Accepted Date: 22 April 2017
Please cite this article as: Huang P, Yang Z, Xu J, Specific intramolecular aromatic C-H insertion of
diazosulfonamides, Tetrahedron (2017), doi: 10.1016/j.tet.2017.04.056.
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Specific intramolecular aromatic C−H
insertion of diazosulfonamides
Peipei Huang, Zhanhui Yang*, and Jiaxi Xu*
State Key Laboratory of Chemical Resource Engineering, Department of Organic Chemistry, Faculty of
Science, Beijing University of Chemical Technology, Beijing 100029, People’s Republic of China

1
ACCEPTED MANUSCRIPT
Tetrahedron
journal homepage: www.elsevier.com
Specific intramolecular aromatic C−H insertion of diazosulfonamides
Peipei Huang, Zhanhui Yang , and Jiaxi Xu
State Key Laboratory of Chemical Resource Engineering, Department of Organic Chemistry, Faculty of Science, Beijing University of Chemical Technology,
Beijing 100029, People’s Republic of China
ARTICLE INFO
ABSTRACT
Article history:
Received
Received in revised form
Accepted
The chemoselectivity in the intramolecular C−H insertion of various diazosulfonamides has
beenexperimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)−H
insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)−H insertion can
be realized specifically by adjusting the diazo-adjacent group. In addition, the general
chemoselectivities in the intramolecular C−H insertions of diazosulfonyl compounds are
summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)−H and aliphatic 1,5-
and 1,6-C(sp3)−H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)−H
insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)−H insertion.
Available online
Keywords:
Chemoselectivity
C−H insertion
Diazosulfonamide
Carbene
2017 Elsevier Ltd. All rights reserved
.
Benzo-γ-sultam
and 1,6-C(sp3)−H insertions could be tuned by the Thorpe-Ingold
1. Introduction
6b
7
effect and catalyst ligand effect.4b Maguire’s
and Zhang’s
The transition metal-catalyzed intramolecular aromatic (sp2) and
aliphatic (sp3) C−H insertions of diazo compounds have provided
one of important and efficient synthetic methods of carbocycles
and heterocycles through the new C−C bond formation.1
Generally, the chemoselectivity in the intramolecular C−H
insertion of diazocarbonyl compounds (Figure 1, 1), including
diazoketones (1, X = CR1R2), diazoesters (1, X = O), and
diazoamides (1, X = NR1), has been well clarified,1 and it has
been widely used to construct complex and useful structures, for
example, natural products.2 Contrastingly, diazosulfonyl
compounds (Figure 1, 2), of which the intramolecular C−H
insertion would lead to thiacycles, have not received much
attention to date. Only a limited number of reports on
diazosulfones (2, X = CR1R2) and diazosulfonates (2, X = O)
have been accessible.3-7 In 1986, Durst and co-workers realized
the aromatic 1,5-C(sp2)−H insertion of (diaryl)methyl
diazosulfones.3 Pioneering work from Novikov’s,4a Du Bois’s,5
and Maguire’s6a groups revealed that diazosulfones and
diazosulfonates were susceptible to the aliphatic 1,6-C(sp3)−H
insertion to deliver the corresponding six-membered
cyclosulfones and δ-sultones under rhodium- and copper-
catalyzed conditions. Although it was stated by Du Bois that
diazosulfones and diazosulfonates had a strong proclivity for the
aliphatic 1,6-C(sp3)−H insertion, the aliphatic 1,5-C(sp3)−H
insertion was also observed in several cases.4b,6b,7 Novikov’s
groups realized the specificity of the aliphatic 1,5-C(sp3)−H
insertion of diazosulfones via copper and cobalt catalyses,
respectively. The specificity was mainly caused by the pendant
aryl,6b,7 alkenyl,7 and allenyl 7 groups that activated their adjacent
C−H bonds.
Figure 1. Intramolecular insertions of diazocarbonyl compounds (1)
and diazosulfonyl compounds (2).
Recently, we put forward the concept of diazosulfonamides (2,
X = NR’),8 and realized the rhodium- and copper-catalyzed
specifically intramolecular aromatic 1,5-C(sp2)−H insertion of
group discovered that the chemoselectivity between aliphatic 1,5-
———
Corresponding author. Tel.: +8610-6443-5565; fax: +8610-6443-5565; e-mail: zhyang@mail.buct.edu.cn
Corresponding author. Tel.: +8610-6443-5565; fax: +8610-6443-5565; e-mail: jxxu@mail.buct.edu.cn

2
Tetrahedron
ACCEPTED MANUSCRIPT
N,N-diaryl diazosulfonamides to prepare N-aryl benzo-γ-
sultams.8 However, when N-aryl-N-alkyl or N,N-dialkyl
diazosulfonamides are employed, the C(sp3)−H insertion—
potentially including 1,4-, 1,5-, and even 1,6-insertion—of the N-
alkyl group of diazosulfonamides also represents one of the
concerned issues in this field (Scheme 1). Thus, the
chemoselectivity will become complex, and it is of significant
use to find out which reaction pathway predominates. We have
experimentally studied the general chemoselectivities between
different types of the intramolecular C−H insertions of
diazosulfonamides, and found that diazosulfonamides favored to
undergo aromatic 1,5-C(sp2)−H insertion only (Scheme 1). We
hope the current study on the chemoselectivity could offer some
guidance to the synthetic community concerning diazosulfonyl
chemistry.
intramolecular aliphatic 1,4-, 1,5-, or 1,6-C(sp3)−H inserton of
diazosulfonamides is not preferred.
Figure 2. Designed diazosulfonamides for the C(sp3)−H insertion
investigations.
2.2. The aromatic sp2 C-H insertion
With the failure to achieve the aliphatic 1,4-, 1,5-, and 1,6-
C(sp3)−H insertions, we moved on to study the aromatic
C(sp2)−H insertion of diazosulfonamides. According to previous
publications,1 the aromatic C−H insertion follows a stepwise
mechanism, including electrophilic addition of carbenoid to aryl
rings and subsequent elimination of metal catalyst. Actually, the
failed reactions of 3c-e,i-l in Figure 2 led us to believe that N-
alkyl groups of diazosulfonamides would exert a disastrous
influence on the aromatic C−H insertion. Thus, the N,N-diaryl
diazosulfonamides were designed. In our previous work,8 N,N-
diphenyl diazosulfonamide 3n underwent the aromatic 1,5-
C(sp2)−H insertion smoothly, delivering benzo-γ-sultam 7n in
28% to 99% yields under different conditions (Scheme 2, entries
1−8). A series of copper and rhodium catalysts was efficient to
catalyze the aromatic C−H insertion, with Rh2(oct)4 the most
efficient. Different symmetric N,N-diaryl diazosulfonamides 3n-
Scheme 1. Aliphatic 1,4-, 1,5-, 1,6-C(sp3)−H and aromatic
1,5-C(sp2)−H insertions of diazosulfonamides.
2. Results and Discussion
2.1. Aliphatic sp3 C−H insertions
To observe the aliphatic C−H insertion selectivity (Scheme 1),
we designed and synthesized
a
number of N-alkyl
diazosulfonamides 3a-m (Figure 2), and subjected them to
various transition-metal catalytic conditions. On the basis of
previously results,1h the aliphatic C−H insertion follows a
u
underwent the aromatic C-H insertion to form the
corresponding benzo-γ-sultams 7n-u in 65% to 99% yields
(Scheme 3). The aromatic C−H insertion was not affected by the
electron-donating-groups such as methoxy and methyl groups on
aryl rings (7o,p), the halo-atoms such as fluoro-, chloro-, or
bromo-atoms (7q,r,s), or the different substituted positions on the
aryl rings (7t,u). The aromatic C(sp2)−H insertion of N,N-diaryl
diazosulfonamides occurred readily, giving rise to benzo-γ-
sultams in morate to excellent yields (Scheme 3).
concerted electrophilic mechanism via
a three-membered
transition state. N,N-N,N-Dibenzylsulfonamide 3a and N-aryl
diazosulfonamides 3b-e were completely consumed and gave
complex brown mixtures, from which no aliphatic 1,4-C(sp3)−H
insertion product β-sultams were observed, even though different
copper and rhodium catalysts in various solvents at different
temperatures were attempted.9 Next, we tested the aliphatic 1,5-
and 1,6-C−H insertions, of which the products would be γ-
sultams and δ-sultams, respectively. Significantly different from
the results of diazosulfones and diazosulfonates, under the tested
conditions, diazosulfonamides 3f-i were completely converted
into complex brown mixtures, without any 1,4-, 1,5-, or 1,6-
C(sp3)−H insertion products observed. In the aliphatic C−H
insertions of diazocarbonyl compounds, the rigid structure such
CO2Et
O
O
cat. solvent, time
See below
EtO2C
S
Ph
O
N
S
N2
O
N
Ph
3n
7n
Entry 1: 1 mol% Rh2(OAc)4,
Entry 2: 1 mol% Rh2(oct)4,
Entry 3: 1 mol% Cu(acac)2,
DCE, rfx, 11 h, 28%;
DCE, rfx, 0.5 h, 99%;
DCE, rfx, 13 h, 91%;
as
a
cyclic component would render unexpected
Entry 4: 1 mol% Cu(OAc)2·H2O, DCE, rfx, 3 h,
Entry 5: 1 mol% Cu(OTf)2, DCE, rfx, 1 h,
Entry 6: 1 mol% (CuOTf)2C6H6, DCE, rfx, 2 h,
Entry 7: 1 mol% Rh2(oct)4,
71%;
79%;
50%;
regioselectivity.10 However, the reactions of similarly structured
diazosulfonamides 3j-m with aliphatic rings gave no identified
products but complex brown mixtures.
DCM, rfx, 0.5 h, 99%;
Entry 8: 0.25 mol% Rh2(oct)4, DCE, rfx, 0.5 h, 99%;
Scheme 2. Our previous reported aromatic 1,5-C(sp2)−H
It is well established that the metalocarbenes prefer to insert
into the benzylic or tertiary C−H bonds;1h however, this empirical
rule apparently does not apply to the reactions of
diazosulfonamides. The results of the reactions of
diazosulfonamides 3a-m preliminarily revealed that the
insertion
of
1-diazo-2-ethoxy-N,N-diphenyl-2-
oxoethanesulfonamide (3n) under different conditions

3
The diazosulfonamides 3a-i do not undergo the aliphatic
ACCEPTED MANUSCRIPT
C−H insertion, no matter how to adjust the N-substituents. It has
been well documented that the carbene reactivity is closely
affected by the adjacent substituents of the diazo group.1h
Therefore, we decided to search for
a new type of
diazosulfonamides to assess the aromatic C(sp2)−H and aliphatic
C(sp3)−H insertions. Replacement of the carboxylate group in
diazosulfonamide 3e with the cyano and benzoyl groups directed
to diazosulfonamides 8a and 9a, respectively (Figure 3).
However, after attempting different diazo transfer reagents under
a number of conditions, the preparation of 8a from the
corresponding 1-cyano-N-methyl-N-phenylmethanesulfonamide
failed.12 Delightedly, 9a was successfully synthesized.
Scheme 3. Our previous aromatic 1,5-C(sp2)−H insertion of
symmetric N,N-diaryl-1-diazo-2-ethoxy-2-
oxoethanesulfonamides
Figure 3. Three representative diazosulfonamides
The reactivity of 9a was evaluated with copper and rhodium
salts as the catalysts under various conditions (Table 1). The
desired aromatic C−H insertion product N-methyl-benzo-γ-
sultam 10a was isolated in only 4% yield, after refluxing 9a in
DCE for 22 h in the presence of 0.5 mol% Rh2(oct)4 as the
catalyst (Table 1, entry 1). At the same catalyst loading, using
toluene as solvent and increasing the temperature not only
improved the yield to 32%, but also shortened the time to 3 h
(Table 1, entry 2). Other Rh catalysts such as Rh2(OAc)4 and
Rh2(esp)2 gave poor results (Table 1, entries 3 and 4). Since
copper catalysts are inexpensive, and they play a vital role in
carbene chemistry, we set our efforts to study their catalytic
activity. A series of copper catalysts, such as Cu(OAc)2·H2O, CuI,
CuCl2·5H2O, CuSO4·5H2O, CuBr, Cu(NO3)2·3H2O, and
Cu(acac)2, showed different reactivities in catalyzing the
aromatic C(sp2)−H insertion (Table 1, entries 5−11), but
Cu(acac)2 outcompeted the others. Refluxing 9a with 2 mol%
Cu(acac)2 in toluene for 9 h gave 10a in 40% yield (Table 1,
entry 14). However, further optimization of the yield by changing
temperature and solvents did not improve the yield further (Table
1, entries 12 and 13). Additionally, all the reactions in Table 1
specifically afforded the aromatic C−H insertion product 10a,
with no aliphatic C−H insertion products detected.
The regioselectivity of the aromatic C-H insertion was also
studied by subjecting set of N-aryl-N-(p-
a
chlorophenyl)diazosulfonamides 3v-aa to the standard conditions
(Scheme 4). The two regiomers were isolated in good to
excellent yields, and the ratios were detected by the 1NMR
analysis of their crude reaction mixtures. The results indicated
that the aromatic C-H functionalization favors to occur on the
more electron-rich aromatic rings. These phenomena were in
accordance with the carbene insertion rules.1
CO2Et
CO2Et
O
S
O
Cl
O
EtO2C
R
O
S
0.5 mol % Rh2(oct)4,
DCE. rfx, 0.5-2 h.
N
S
O
R
N
+
O
N
N2
R
3v-aa
7'v-aa
7v-aa
Cl
CO2Et
Cl
CO2Et
O
(1) R = H, 7v 35%, 7'v 40%;
7v:7'v = 46:54;
(2) R = 4-Me, 7w 25%, 7'w 30%;
7w:7'w = 49:51;
(3) R = 4-MeO,7x 20%, 7'x 34%;
7x:7'x = 39:61.
Cl
O
S
R
S
O
N
O
N
+
R
(4) R = 3,5-diMe, 7y 9%, 7'y 17%;
7y:7'y = 49:51;
(5) R =3,5-diMeO, 7z 13%, 7'z 63%;
7z:7'z = 17:83.
7v-z
7'v-z
Cl
CO2Et
CO2Et
Table 1 Reaction condition optimization of the aromatic 1,5-
Cl
C-H insertiona
O
S
O
S
O
N
+
O
N
(6) 7aa:7'aa = 15:85, 99% total yield
7aa
7'aa
Cl
Scheme 4. Our previous work on the regioselectivity in the
aromatic 1,5-C(sp2)−H insertion of N,N-diaryl diazosulfonamides.
Time Yield
Entry
Cat. (mol%)
Solvent Temp.
(h) (%)b
We postulated that the occurrence of the aromatic C−H
insertion should be a result of the Thorpe-Ingold effect11 exerted
by the N,N-diaryl substituents in diazosulfonamides 3n-3u.8 The
steric effect between the two N,N-diaryl rings in 3n-3u is larger
than that between the N-alkyl and N-aryl groups in 3c-3e, making
one of the N,N-diaryl rings closer to the generated
metalocarbenes derived from 3n-3u. Consequently, the aromatic
C−H insertion occurs smoothly. In other words, the aromatic
C(sp2)−H insertion was realized by adjusting the steric hindrance
of the N-substituents of diazosulfonamides.
1
2
3
4
Rh2(oct)4 (0.5)
Rh2(oct)4 (0.5)
Rh2(OAc)4 (1)
Rh2(esp)2 (2)
DCE
PhMe
PhMe
PhMe
rfx
rfx
rfx
rfx
22
3
4
32
11
1
44
24
5
6
Cu(OAc)2·H2O (2) PhMe
CuI (2) PhMe
rfx
rfx
24
24
25
21

4
Tetrahedron
ACCEPTED MANUSCRIPT
aReactions were conducted on a 0.5 mmol scale in 10 mL of toluene. The
yields were obtained by chromatography on silica gel.
7
8
9
CuCl2·5H2O (2)
CuSO4·5H2O (2) PhMe
CuBr (2) PhMe
PhMe
rfx
rfx
rfx
24
24
24
7
11
19
2.3. Chemoselectivity of intramolecular C−H insertions of
diazosulfones, diazosulfonates, and diazosulfonamides
With the above experimental results, we would like to
compare the intramolecular C−H insertion chemoselectivities of
10 Cu(NO3)2·3H2O (2) PhMe
rfx
rfx
24
9
21
diazosulfones,
diazosulfonates,
and
diazosulfonamides.
11
12
13
Cu(acac)2 (2)
Cu(acac)2 (2)
Cu(acac)2 (2)
PhMe
PhMe 80 oC 24
40
36
37
Generally, in the aromatic 1,5-C(sp2)−H insertion, only one new
stereocenter is generated, resulting in formation of one pair of
enantiomers. However, in the aliphatic 1,4-, 1,5-, and 1,6-
C(sp3)−H insertions, there will always be two stereocenters
generated, and the diastereoselectivity, namely cis- and trans-
selectivity, will be a seriously concerned issue if the aliphatic
insertion does not occur at a terminal methyl C−H bond. After
carefully analysing the publications on diazosulfones and
diazosulfonates,3-7 and our current results, we give the general
intramolecular C−H insertion chemoselectivities of the three
kinds of diazosulfonyl compounds in Table 3.
DCM rfx 24
a All the reactions were conducted on a 0.25 mmol scale in 10 mL of solvent.
b Isolated yield by chromatography on silica gel.
The
chemoselectivities
of
other
N-alkyl-N-aryl
diazosulfonamides 9b-k were studied under the optimal
conditons (Table 2). Regardless of the N-alkyl substituents,
diazosulfonamides 9a-d smoothly underwent the aromatic C−H
insertion exclusively, yielding the corresponding N-alkyl benzo-
γ-sultams 10a-d in 40%, 47%, 24%, and 26% yields, respectively.
In the purification step, very careful attention was paid to
detecting possible aliphatic C−H insertion products. To our
disappointment, we did not observe any 1,4-insertion products in
the reactions of 9b,c,d, and 1,5- or 1,6-insertion products in the
reaction of 9b, either. N,N-Diphenyl diazosulfonamide 9e
showed the best reactivity toward the formal aromatic C-H
insertion, and product 10e was isolated in the highest yield of
59%, agreeing well with our previous report.8 By using
diazosulfonamides 9f-j bearing active benzylic C−H bonds, the
potential aliphatic 1,4-C(sp3)−H insertion was not observed.
Instead, the corresponding aromatic 1,5-C(sp2)−H insertion
products N-benzyl benzo-γ-sultams 10f-10j were obtained in
47%, 18%, 27%, 32% and 30% yields, respectively. In the
reactions of 9d,f-j, there were no aliphatic 1,4-C(sp3)−H insertion
products β-sultams observed. To extend the substrate scope,
diazosulfonamide 9k with an adjacent acetyl group was also
prepared and easily underwent the similar aromatic C(sp2)−H
insertion, giving rise to the desired product 10k in 37% yield.
Generally, diazosulfones prefer both aromatic 1,5-C(sp2)−H
and aliphatic 1,5-C(sp3)−H and 1,6-C(sp3)−H insertions, while
diazosulfonates prefer only aliphatic 1,5- and 1,6-C(sp3)−H
insertions. It is noteworthy that the intramolecular 1,5-(sp3)−H
insertion favorably delivers trans-products. This has been
demonstrated by Maguire’s, Novikov’s, and Zhang’s results
catalyzed by copper, rhodium, and cobalt catalysts,
respectively.4b,c,6,7 The cis-selectivity is favored in the aliphatic
1,6-C(sp3)−H insertion only. For example, in Nikonov’s and Du
Bois’s studies, the six-membered cis-cyclosulfones and cis-δ-
sultones were generated predominantly under the catalysis of
rhodium catalysts.4a,5 In Maguire’s studies, the cis-cyclosulfones
were obtained exclusively under the catalysis of copper
catalysts.6a Contrastingly, our studies demonstate that
diazosulfonamides only undergo the aromatic 1,5-C(sp2)−H
insertion.8
Table 3 General chemoselectivities in the intramolecular C−H
insertions of diazosulfonyl compounds.a,b
Table 2 The aromatic 1,5-C−H insertion of N-alkyl-N-diaryl
diazosulfonamidesa
3. Conclusion
The chemoselectivity in the intramolecular C−H insertions of
diazosulfonamides has been experimentally studied. The results
reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)−H insertion of
diazosulfonamides does not occur, no matter how to adjust their
N-substituents or diazo-adjacent groups, no matter how to
optimize the reaction conditions. However, the aromatic 1,5-
C(sp2)−H insertion can be realized by adjusting both the N-
substituents and the diazo-adjacent groups, providing
a
complimentary method to construct the benzo-γ-sultam
structures.13
In addition, we summarized the general chemoselectivities of
the intramolecular C−H insertions of diazosulfonyl compounds.

5
Generally, diazosulfones undergo both aromatic 1,5-C(sp2)−H
and aliphatic 1,5- and 1,6-C(sp3)−H insertions, while
diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)−H
insertions. However, diazosulfonamides only undergo the
aromatic 1,5-C(sp2)−H insertion. We hope our summary on the
chemoselectivity could offer some guidance to the synthetic
community concerning diazosulfonyl compounds.
62.2, 57.6, 51.2, 14.0. IR (KBr, cm-1): 1740, 1342, 1150.
ACCEPTED MANUSCRIPT
HRMS (ESI) calcd for C18H22NO4S+ [M+H+] m/z: 348.1264,
found 348.1271.
4.1.2. Ethyl
nitrophenyl)sulfamoyl]acetate (12b)
2-[N-benzyl-N-(4-
Colorless crystals, 0.74 g, 78% yield, mp 85
−
86 oC. Rf = 0.5
1
(silica gel plate, EA:PE = 1:2, v/v). H NMR (400 MHz,
4. Experimental Section
CDCl3) δ: 8.12 (d,
7.42 – 7.28 (m, 5H), 5.04 (s, 2H), 4.33 (q,
4.03 (s, 2H), 1.37 (t,
J
= 8.7 Hz, 2H), 7.44 (d,
J
J
= 8.7 Hz, 2H),
= 7.1 Hz, 2H),
General Information
J
= 7.1 Hz, 3H). 13C NMR (101 MHz,
Dichloromethane and 1,2-dichloroethane (DCE) were
CDCl3) δ: 163.6, 147.5, 143.9, 137.9, 129.8, 129.1, 129.0,
128.8, 123.7, 62.6, 56.3, 54.2, 14.0. IR (KBr, cm-1): 1738,
1347, 1162. HRMS (ESI) calcd for C17H19N2O6S+ [M+H+]
m/z: 379.0958, found 379.0959.
refluxed over CaH2 and freshly distilled prior to use.
Melting points were obtained on a melting point apparatus
and are uncorrected. 1H and 13C NMR spectra were recorded
on a 400 MHz Bruker spectrometer in CDCl3 with TMS as
an internal standard and the chemical shifts (δ) are reported
4.1.3. Ethyl
phenylsulfamoyl)acetate (12c)
2-(N-isopropyl-N-
in parts per million (ppm). The IR spectra (KBr pellets,
v
[cm−1]) were taken on a FTIR Nicolet 3700 spectrometer.
HRMS measurements were carried out on an agilent
LC/MSD TOF mass spectrometer. TLC separations were
o
Blue crystals, 0.49 g, 69% yield, mp 58
(silica gel plate, EA:PE = 1:10, v/v). H NMR (400 MHz,
CDCl3) δ: 7.46 – 7.39 (m, 3H), 7.37 – 7.31 (m, 2H), 4.51
−
59 C. Rf = 0.2
1
performed on silica gel GF254 plates, and the plates were
o
(hept,
J
= 6.7 Hz, 1H), 4.28 (q,
J
= 7.1 Hz, 2H), 3.98 (s, 2H),
visualized under UV light. Petroleum ether (PE, 30
−
60 C)
1.33 (t,
J
= 7.1 Hz, 3H), 1.16 (d,
J
= 6.7 Hz, 6H). 13C NMR
and ethyl acetate (EA) were used for column separation. The
preparation of diazosulfonamides 3n-aa and benzo-γ-
sultams 7n-aa, together with their analytical data and 1H and
13C spectra have been reported in our previous
communication.8
(101 MHz, CDCl3) δ: 163.4, 134.2, 132.7, 129.2, 129.1,
62.3, 56.5, 52.3, 22.4, 14.0. IR (KBr, cm-1): 1739, 1368,
1166. HRMS (ESI) calcd for C13H20NO4S+ [M+H+] m/z
:
286.1108, found 286.1113.
It is noteworthy that the signals of the carbons attached with
diazo group in diazosulfonamides 3 and 9 were not observed in
their 13C NMR spectra. Similar observations were also reported
by Novikov and Du Bios in their synthesis of diazosulfones and
diazosulfonates, respectively.4a,5
4.1.4. Ethyl 2-(N-benzyl-N-phenylsulfamoyl)acetate
(12d)
Pink oil, 0.51 g, 62% yield, Rf = 0.3 (silica gel plate, EA:PE
1
= 1:5, v/v). H NMR (400 MHz, CDCl3) δ: 7.39 – 7.35 (m,
2H), 7.34 – 7.29 (m, 2H), 7.29 – 7.26 (m, 1H), 7.26 – 7.19
The diazosulfonamides 3 were readily prepared according to
the sequence depicted as following. Direct sulfonation of
secondary amines 11, which were easily prepared by the
reductive amination of aromatic amines and aldehydes with
NaBH4, Chan-Lam coupling of aromatic amines and
(m, 5H), 4.91 (s, 2H), 4.32 (q,
J = 7.1 Hz, 2H), 4.01 (s, 2H),
1.36 (t,
J
= 7.1 Hz, 3H). 13C NMR (101 MHz, CDCl3) δ:
163.6, 138.2, 136.3, 129.4, 129.4, 128.5, 128.40, 128.37,
127.7, 62.4, 56.9, 54.6, 14.0. IR (KBr, cm-1): 1738, 1353,
1162. HRMS (ESI) calcd for C17H20NO4S+ [M+H+] m/z
:
haloarenes,14
ethoxycarbonylmethanesulfonyl
or
commercially
chloride
available,
afforded
with
the
334.1108, found 334.1110.
corresponding sulfonamides 12. Further diazonation of 12 with
TsN3 easily furnished the corresponding diazosulfonamides 3 in
moderate to good yields.
4.1.5. Ethyl 2-(N-methyl-N-phenylsulfamoyl)acetate
(12e)
Brown oil, 2.12 g, 82% (10 mmol scale), Rf = 0.3 (silica gel
1
plate, EA:PE = 1:5, v/v). H NMR (400 MHz, CDCl3) δ:
7.52 – 7.45 (m, 2H), 7.44 – 7.37 (m, 2H), 7.35 – 7.29 (m,
1H), 4.25 (q,
J = 7.2 Hz, 2H), 3.94 (s, 2H), 3.41 (s, 3H),
1.31 (t,
J
= 7.1 Hz, 3H). 13C NMR (101 MHz, CDCl3) δ:
163.4, 140.7, 129.5, 127.9, 127.1, 62.4, 54.0, 39.7, 13.9. IR
(KBr, cm-1): 1739, 1355, 1179. HRMS (ESI) calcd for
C11H16NO4S+ [M+H+] m/z: 258.0795, found 258.0799.
4.1. Preparation of sulfonamides 12a-m
Secondary amine 11 (5 mmol) was dissolved in 10 mL of
dry dichloromethane (DCM) in a 50-mL one-necked flask,
then to the flask was slowly added a solution of ethyl
chlorosulfonylacetate (0.467 g, 2.5 mmol) in 5 mL of DCM
during 1 min. The resultant solution was stirred at room
temperature for 24 h. After removal of the solvent, the
mixture was directly subjected to column chromatography to
recover the secondary amine and to obtain the desired
4.1.6. Ethyl
2-(N-benzyl-N-
butylsulfamoyl)acetate(12f)
Yellow oil, 0.64 g, 82% yield, Rf = 0.4 (silica gel plate,
1
EA:PE = 1:5, v/v). H NMR (400 MHz, CDCl3) δ: 7.40 –
7.29 (m, 5H), 4.44 (s, 2H), 4.26 (q,
2H), 3.22 (t, = 7.6 Hz, 2H), 1.45 (p,
(t, = 7.1 Hz, 3H), 1.22 (d,
J
= 7.1 Hz, 2H), 3.94 (s,
= 7.6 Hz, 2H), 1.32
= 7.6 Hz, 2H), 0.82 (t, = 7.3
J
J
J
J
J
product 12
.
Hz, 3H).13C NMR (101 MHz, CDCl3) δ: 163.4, 136.2,
128.6, 128.2, 127.9, 62.2, 56.6, 52.0, 48.1, 30.2, 19.7, 14.0,
13.5. IR (KBr, cm-1): 1740, 1344, 1153. HRMS (ESI) calcd
for C15H24NO4S+ [M+H+] m/z: 314.1421, found 314.1420.
4.1.1. Ethyl 2-(N,N-dibenzylsulfamoyl)acetate (12a)
Yellow oil, 1.65 g, 95% yield (10 mmol scale), Rf = 0.5
(silica gel plate, EA:PE = 1:5, v/v). H NMR (400 MHz,
1
CDCl3) δ: 7.34 – 7.24 (m, 10H), 4.40 (s, 4H), 4.20 (q,
7.2 Hz, 2H), 3.83 (s, 2H), 1.26 (t,
= 7.2 Hz, 3H). 13C NMR
(101 MHz, CDCl3) δ: 163.3, 135.3, 128.7, 128.6, 128.0,
J =
4.1.7. Ethyl 2-(N-benzyl-N-propylsulfamoyl)acetate
(12g)
J

6
Tetrahedron
ACCEPTED MANUSCRIPT
Yellow oil, 0.4 g, 29% yield, Rf = 0.4 (silica gel plate,
EA:PE = 1:5, v/v). H NMR (400 MHz, CDCl3) δ: 7.40 –
7.06 – 7.00 (m, 1H), 4.16 – 4.07 (m, 4H), 4.04 (s, 2H), 3.19
(t, J = 8.5 Hz, 2H), 1.22 (t, J
= 7.1 Hz, 3H). 13C NMR (101
1
7.27 (m, 5H), 4.45 (s, 2H), 4.26 (q,
2H), 3.19 (d, = 7.6 Hz, 2H), 1.49 (h,
(t, = 7.2 Hz, 3H), 0.81 (t,
= 7.2 Hz, 3H). 13C NMR (101
J
= 7.2 Hz, 2H), 3.95 (s,
MHz, CDCl3) δ: 162.8, 141.3, 131.5, 127.8, 125.5, 124.0,
113.7, 62.4, 53.8, 50.7, 28.0, 13.8. IR (KBr, cm-1): 1740,
1362, 1166. HRMS (ESI) calcd for C12H16NO4S+ [M+H+]
m/z: 270.0795, found 270.0794.
J
J
= 7.4 Hz, 2H), 1.32
J
J
MHz, CDCl3) δ: 160.8, 136.2, 128.6, 128.1, 127.9, 62.1,
52.9, 51.1, 21.5, 14.3, 11.1. IR (KBr, cm-1): 1739, 1344,
115. HRMS (ESI) calcd for C14H22NO4S+ [M+H+] m/z
:
4.1.13. Ethyl
2-[(1,2,3,4-tetrahydroisoquinolin-2-
yl)sulfonyl]acetate (12m)
300.1264, found 300.1273.
Colorless oil, 0.49 g, 86% yield (4 mmol scale), Rf = 0.5
(silica gel plate, EA:PE = 1:2, v/v). H NMR (400 MHz,
CDCl3) δ: 7.24 – 7.12 (m, 3H), 7.11 – 7.05 (m, 1H), 4.57 (s,
1
4.1.8. Ethyl
phenethylsulfamoyl]acetate (12h)
2-[N-benzyl-N-
Yellow oil, 0.9 g, 71% yield, Rf = 0.4 (silica gel plate,
EA:PE = 1:5, v/v). H NMR (400 MHz, CDCl3) δ: 7.43 –
7.26 (m, 6H), 7.24 – 7.16 (m, 2H), 7.10 – 7.05 (m, 2H), 4.48
2H), 4.20 (q,
Hz, 2H), 2.97 (t,
J
= 7.1 Hz, 2H), 4.00 (s, 2H), 3.66 (t,
J
= 5.9
1
J = 5.9 Hz, 2H), 1.27 (t, J = 7.1 Hz,
3H).13C NMR (101 MHz, CDCl3) δ: 163.2, 133.2, 131.7,
129.0, 126.9, 126.5, 126.2, 62.3, 55.2, 47.2, 43.8, 29.1, 13.9.
IR (KBr, cm-1): 1738, 1358, 1162. HRMS (ESI) calcd for
C13H18NO4S+ [M+H+] m/z: 284.0951, found 284.0951.
(s, 2H), 4.23 (q,
J = 7.2 Hz, 2H), 3.78 (s, 2H), 3.45 (t, J =
7.6 Hz, 2H), 2.73 (t,
J
= 7.6 Hz, 2H), 1.30 (d, J = 7.2 Hz,
3H). 13C NMR (101 MHz, CDCl3) δ: 163.4, 138.3, 135.9,
128.8, 128.6, 128.5, 128.1, 126.6, 62.2, 56.6, 52.3, 49.7,
35.2, 14.0. IR (KBr, cm-1): 1739, 1344,1151. HRMS (ESI)
4.2. Prepartion of diazosulfonamides 3a-m
calcd for C19H24NO4S+[M+H+] m/z
: 362.1421, found
362.1424.
Sulfonamide 12 (1 mmol) and tosyl azide (197 mg, 1 mmol)
were dissolved in 5 mL of dry acetonitrile in a 25-mL one-
necked flask, which was immersed into an ice-water bath.
The flask was sealed by a rubber stopper. To the flask was
slowly added a solution of DBU (228 mg, 1.5 mmol) in 2.5
mL of acetonitrile via a syringe during 1 min. After 15 min,
the reaction was complete. Removal of the solvent and
subjecting the mixture directly to column chromatography
4.1.9. Ethyl
phenylsulfamoyl)acetate (12i)
Yellow oil, 0.19 g, 36% yield (3.3 mmol scale),Rf = 0.4
(silica gel plate, EA:PE = 1:5, v/v). H NMR (400 MHz,
2-(N-isopentyl-N-
1
CDCl3) δ: 7.49 – 7.39 (m, 4H), 7.38 – 7.33 (m, 1H), 4.28 (q,
J
= 7.1 Hz, 2H), 3.92 (s, 2H), 3.77 (d,
J
= 7.4 Hz, 2H), 1.69
– 1.57 (m, 1H), 1.33 (td,
J
= 7.1, 3.4 Hz, 5H), 0.85 (d, J =
afforded the desired product 3.
6.6 Hz, 6H). 13C NMR (101 MHz, CDCl3) δ: 163.5, 138.4,
129.5, 129.2, 128.3, 62.3, 54.3, 51.1, 37.7, 25.2, 22.3, 14.0.
IR (KBr, cm-1): 1740, 1354, 1165. HRMS (ESI) calcd for
C15H24NO4S+ [M+H+] m/z: 314.1421, found 314.1427.
4.2.1. Ethyl
2-diazo-2-(N,N-
dibenzylsulfamoyl)acetate (3a)
Yellow crystals, 0.17 g, 47% yield, mp 69
o
−
71 C, Rf = 0.4
1
(silica gel plate, EA:PE = 1:10, v/v). H NMR (400 MHz,
CDCl3) δ: 7.36 – 7.24 (m, 10H), 4.52 (s, 4H), 4.19 (q,
7.2 Hz, 2H), 1.25 (t,
= 7.2 Hz, 3H). 13C NMR (101 MHz,
4.1.10. Ethyl
phenylsulfamoyl)acetate (12j)
Yellow oil, 0.47 g, 58% yield, Rf = 0.15 (silica gel plate,
EA:PE = 1:10, v/v). H NMR (400 MHz, CDCl3) δ: 7.43 –
2-(N-cyclohexyl-N-
J
=
J
CDCl3) δ: 160.6, 135.3, 128.7, 128.4, 128.0, 62.0, 52.1,
14.3. IR (KBr, cm-1): 2120, 1712, 1369, 1154. HRMS (ESI)
calcd for C18H20N3O4S+ [M+H+] m/z: 374.1169, found
374.1175.
1
7.39 (m, 3H), 7.34 – 7.30 (m, 2H), 4.28 (q,
J = 7.1 Hz, 2H),
3.98 (s, 2H), 2.06 – 1.98 (m, 2H), 1.80 – 1.70 (m, 2H), 1.58
– 1.51 (m, 1H), 1.42 – 1.24 (m, 6H), 1.20 – 1.05 (m, 2H),
0.94 – 0.80 (m, 1H). 13C NMR (101 MHz, CDCl3) δ: 163.3,
134.9, 132.6, 129.0, 129.0, 62.3, 60.0, 56.5, 33.0, 25.9, 24.9,
14.0. IR (KBr, cm-1): 1739, 1354, 1167. HRMS (ESI) calcd
for C16H24NO4S+[M+H+] m/z: 326.1421, found 326.1429.
4.2.2. Ethyl
nitrophenyl)sulfamoyl] -2-diazoacetate (3b)
Yellow crystals, 0.13 g, 31% yield, mp 106
108 oC, Rf = 0.2
(silica gel plate, EA:PE = 1:5, v/v). H NMR (400 MHz,
CDCl3) δ: 8.13 (d, = 8.7 Hz, 2H), 7.46 (d, = 8.7 Hz, 2H),
7.40 – 7.33 (m, 3H), 7.30 – 7.25 (m, 2H), 5.18 (s, 2H), 4.40
(q, = 7.1 Hz, 2H), 1.38 (t,
= 7.1 Hz, 3H). 13C NMR (101
2-[N-benzyl-N-(4-
−
1
J
J
4.1.11. Ethyl
yl)sulfonyl]acetate (12k)
Yellow oil, 0.54 g, 96% yield (4 mol scale), Rf = 0.3 (silica
gel plate, EA:PE = 1:5, v/v). H NMR (400 MHz, CDCl3) δ:
2-[(1,2,3,4-tetrahydroquinolin-1-
J
J
MHz, CDCl3) δ: 160.7, 147.5, 144.0, 137.8, 129.8, 129.1,
128.9, 128.4 , 123.8 , 62.4, 56.8, 14.4. IR (KBr, cm-1): 2125,
1737, 1371, 1161. HRMS (ESI) calcd for C17H17N4O6S+
[M+H+] m/z: 405.0863, found 405.0873
1
7.66 (d,
7.3 Hz, 1H), 7.10 – 7.03 (m, 1H), 4.13 (q,
4.05 (s, 2H), 3.86 (t, = 5.6 Hz, 2H), 2.85 (t,
2H), 2.04 (p, = 6.5 Hz, 2H), 1.23 (t,
= 7.1 Hz, 3H).13C
J
= 8.3 Hz, 1H), 7.21 – 7.15 (m, 1H), 7.13 (d,
= 7.1 Hz, 2H),
= 6.4 Hz,
J =
J
J
J
J
J
4.2.3. Ethyl 2-diazo-2-(N-isopropyl-N-
NMR (101 MHz, CDCl3) δ: 162.7, 136.4, 129.6, 129.5,
126.8, 124.5, 121.8, 62.4, 55.8, 47.2, 27.1, 22.7, 13.9. IR
(KBr, cm-1): 1739, 1357, 1157. HRMS (ESI) calcd for
C13H18NO4S+ [M+H+] m/z: 284.0951, found 284.0957.
phenylsulfamoyl)acetate (3c)
Yellow oil, 0.27 g, 88% yield, Rf = 0.5 (silica gel plate,
1
EA:PE = 1:5, v/v). H NMR (400 MHz, CDCl3) δ: 7.49 –
7.39 (m, 3H), 7.30 – 7.22 (m, 2H), 4.71 (hept,
1H), 4.36 (q, = 7.1 Hz, 2H), 1.36 (t, = 7.1 Hz, 3H), 1.17
(d,
= 6.7 Hz, 6H). 13C NMR (101 MHz, CDCl3) δ: 160.6,
J = 6.7 Hz,
J
J
4.1.12. Ethyl 2-(indolin-1-ylsulfonyl)acetate (12l)
J
Yellow oil, 0.47 g, 87% yield (4 mmol scale), Rf = 0.3
134.0, 132.1, 129.3, 129.2, 62.2, 52.8, 22.4, 14.4. IR (KBr,
cm-1): 2121, 1716, 1369, 1165. HRMS (ESI) calcd for
C13H18N3O4S+ [M+H+] m/z: 312.1013, found 312.1017.
1
(silica gel plate, EA:PE = 1:5, v/v). H NMR (400 MHz,
CDCl3) δ: 7.38 (d,
J = 8.0 Hz, 1H), 7.24 – 7.16 (m, 2H),

7
NMR (101 MHz, CDCl3) δ: 160.8, 138.3, 129.5 , 128.6,
ACCEPTED MANUSCRIPT
128.6, 62.1, 51.8, 37.8, 25.3, 22.3, 14.4. IR (KBr, cm-1):
2121, 1713, 1370, 1165. HRMS (ESI) calcd for
C15H22N3O4S+ [M+H+] m/z: 340.1326, found 340.1335.
4.2.4. Ethyl 2-(N-benzyl-N-phenylsulfamoyl)-2-
diazoacetate (3d)
Yellow oil, 0.29 g, 82% yield. Rf = 0.3 (silica gel plate,
EA:PE = 1:10, v/v). H NMR (400 MHz, CDCl3) δ: 7.36 –
1
4.2.10. Ethyl 2-(N-cyclohexyl-N-phenylsulfamoyl)-
7.28 (m, 3H), 7.28 – 7.19 (m, 7H), 5.05 (s, 2H), 4.38 (q,
J =
2-diazoacetate (3j)
Yellow crystals, 0.36 g, 100% yield, mp 74
7.2 Hz, 2H), 1.37 (t,
J
= 7.1 Hz, 3H). 13C NMR (101 MHz,
o
CDCl3) δ: 160.8, 138.1, 136.3, 129.5, 128.7, 128.6, 128.4,
128.4, 127.7, 62.3, 57.5, 14.41. IR (KBr, cm-1): 2122, 1711,
1370, 1161. HRMS (ESI) calcd for C17H18N3O4S+ [M+H+]
m/z: 360.1013, found 360.1030.
−
75 C,Rf = 0.4
1
(silica gel plate, EA:PE = 1:10, v/v). H NMR (400 MHz,
CDCl3) δ: 7.45 – 7.38 (m, 3H), 7.27 – 7.19 (m, 2H), 4.36 (q,
= 7.1 Hz, 2H), 4.32 – 4.19 (m, 1H), 2.09 – 1.98 (m, 2H),
J
1.81 – 1.70 (m, 2H), 1.57 – 1.52 (m, 1H), 1.48 – 1.36 (m,
4.2.5. Ethyl 2-diazo-2-(N-methyl-N-
phenylsulfamoyl)acetate (3e)
2H), 1.36 (t,
J = 7.1 Hz, 3H), 1.17 – 1.02 (m, 2H), 0.96 –
0.79 (m, 1H). 13C NMR (101 MHz, CDCl3) δ: 160.6, 134.6,
132.0, 129.2, 129.1, 62.1, 60.4, 33.0, 25.9, 25.0, 14.4. IR
(KBr, cm-1): 2120, 1716, 1370, 1168. HRMS (ESI) calcd for
C16H22N3O4S+ [M+H+] m/z: 352.1326, found 352.1331.
Yellow oil, 0.94 g, 66% yield, Rf = 0.4 (silica gel plate,
1
EA:PE = 2:15, v/v). H NMR (400 MHz, CDCl3) δ: 7.45 –
7.30 (m, 5H), 4.31 (q,
J
J = 7.2 Hz, 2H), 3.49 (s, 3H), 1.31 (t,
= 7.2 Hz, 3H). 13C NMR (101 MHz, CDCl3) δ: 160.7,
140.4, 129.5, 128.1, 126.5, 62.2, 40.1, 14.3. IR (KBr, cm-1):
2121, 1713, 1371, 1150. HRMS (ESI) calcd for
C11H14N3O4S+ [M+H+] m/z: 284.0700, found 284.0708.
4.2.11. Ethyl 2-diazo-2-[(1,2,3,4-
tetrahydroquinolin-1-yl)sulfonyl]acetate (3k)
Yellow crystals, 0.23 g, 73% yield, mp 72
(silica gel plate, EA:PE = 1:5, v/v). H NMR (400 MHz,
o
−
74 C, Rf = 0.5
1
4.2.6. Ethyl 2-(N-benzyl-N-butylsulfamoyl)-2-
CDCl3) δ: 7.61 – 7.56 (m, 1H), 7.22 – 7.16 (m, 1H), 7.14 –
diazoacetate (3f)
Yellow oil, 0.23 g, 68% yield, Rf = 0.6 (silica gel plate,
EA:PE = 1:5, v/v). H NMR (400 MHz, CDCl3) δ: 7.39 –
7.11 (m, 1H), 7.10 – 7.05 (m, 1H), 4.17 (q,
3.98 (t, = 6.4 Hz, 2H), 2.77 (t, = 6.4 Hz, 2H), 2.04 (p,
6.3 Hz, 2H), 1.18 (t,
= 7.1 Hz, 3H). 13C NMR (101 MHz,
J = 7.1 Hz, 2H),
J
J
J =
1
J
CDCl3) δ: 160.0, 136.0, 130.1, 129.4, 126.8, 124.6, 121.5,
62.1, 47.9, 27.2, 22.7, 14.0. IR (KBr, cm-1): 2120, 1714,
1370, 1159. HRMS (ESI) calcd for C13H16N3O4S+ [M+H+]
m/z: 310.0856, found 310.0860.
7.28 (m, 5H), 4.52 (s, 2H), 4.28 (q,
= 7.6 Hz, 2H), 1.44 (p, = 7.5 Hz, 2H), 1.31 (t,
3H), 1.23 (d, = 7.2 Hz, 2H), 0.83 (t,
= 7.2 Hz, 3H). 13C
NMR (101 MHz, CDCl3) δ: 160.8, 136.2, 128.6, 128.1,
127.9, 62.0, 52.8, 49.1, 30.1, 19.8, 14.3, 13.6. IR (KBr, cm-
1): 2120, 1714, 1370, 1168. HRMS (ESI) calcd for
C15H22N3O4S+ [M+H+] m/z: 340.1326, found 340.1330
J
= 7.2 Hz, 2H), 3.31 (t,
J
J
J
= 7.2 Hz,
J
J
4.2.12. Ethyl 2-diazo-2-(indolin-1-
ylsulfonyl)acetate (3l)
Yellow oil, 0.17 g, 59% yield, Rf = 0.5 (silica gel plate,
1
4.2.7. Ethyl 2-(N-benzyl-N-propylsulfamoyl)-2-
EA:PE = 1:5, v/v). H NMR (400 MHz, CDCl3) δ: 7.30 –
diazoacetate (3g)
7.26 (m, 1H), 7.25 – 7.18 (m, 2H), 7.10 – 7.04 (m, 1H), 4.33
(t,
J
= 8.5 Hz, 2H), 4.18 (q,
J = 7.1 Hz, 2H), 3.15 (t, J = 8.4
Yellow oil, 0.320 g, 98% yield, Rf = 0.5 (silica gel plate,
EA:PE = 1:5, v/v). H NMR (400 MHz, CDCl3) δ: 7.42 –
= 7.1 Hz, 3H). 13C NMR (101 MHz,
1
Hz, 2H), 1.20 (t,
J
CDCl3) δ: 160.2, 140.7, 132.2, 127.8, 125.6, 124.4, 114.3,
7.28 (m, 5H), 4.52 (s, 2H), 4.28 (q,
= 7.6 Hz, 2H), 1.49 (h, = 7.5 Hz, 2H), 1.31 (t,
3H), 0.81 (t,
= 7.4 Hz, 3H). 13C NMR (101 MHz, CDCl3)
J
= 7.2 Hz, 2H), 3.27 (t,
62.2, 51.3, 28.0, 14.1. IR (KBr, cm-1): 2120, 1712, 1372,
J
J
J
= 7.2 Hz,
1162. HRMS (ESI) calcd for C12H13N3O4SNa+ [M+Na+] m/z
:
J
318.0519, found 318.0505.
δ: 160.8, 136.2, 128.6, 128.1, 127.9 , 62.1, 52.9, 51.1, 21.5,
14.3 , 11.1. IR (KBr, cm-1): 2119, 1713, 1353, 1153. HRMS
(ESI) calcd for C14H20N3O4S+ [M+H+] m/z: 326.1169, found
326.1176.
4.2.13. Ethyl 2-diazo-2-[(1,2,3,4-
tetrahydroisoquinolin-2-yl)sulfonyl]acetate (3m)
Yellow crystals, 0.25 g, 82% yield (0.98 mmol scale), mp
o
1
4.2.8. Ethyl 2-(N-benzyl-N-phenethylsulfamoyl)-2-
diazoacetate (3h)
47
NMR (400 MHz, CDCl3) δ: 7.22 – 7.17 (m, 2H), 7.17 – 7.13
(m, 1H), 7.12 – 7.06 (m, 1H), 4.57 (s, 2H), 4.23 (q, = 7.1
Hz, 2H), 3.67 (t, = 5.9 Hz, 2H), 2.97 (t, = 5.9 Hz, 2H),
1.26 (t,
= 7.1 Hz, 3H). 13C NMR (101 MHz, CDCl3) δ:
−48 C, Rf = 0.5 (silica gel plate, EA:PE = 1:5, v/v). H
J
Yellow oil, 0.37 g, 97% yield, Rf = 0.5 (silica gel plate,
1
J
J
EA:PE = 1:5, v/v). H NMR (400 MHz, CDCl3) δ: 7.39 –
J
7.27 (m, 6H), 7.24 – 7.16 (m, 2H), 7.10 – 7.04 (m, 2H), 4.52
160.6, 133.3, 131.5, 128.9, 126.9, 126.6, 126.3, 62.2, 47.4,
(s, 2H), 4.25 (d,
J
= 7.2 Hz, 2H), 3.54 (d,
J = 7.6 Hz, 2H),
44.3, 29.0, 14.2. IR (KBr, cm-1): 2122, 1713, 1371, 1161.
2.74 (d, = 7.6 Hz, 2H), 1.28 (d,
J
J
= 7.2 Hz, 3H). 13C NMR
HRMS (ESI) calcd for C13H16N3O4S+ [M+H+] m/z
:
(101 MHz, CDCl3) δ: 160.6, 138.2, 135.8, 128.8, 128.7,
128.8, 128.3, 128.1, 126.6, 62.0, 53.2, 50.7, 35.3, 14.3. IR
(KBr, cm-1): 2119, 1713, 1369, 1179. HRMS (ESI) calcd for
C19H22N3O4S+[M+H+] m/z: 388.1326, found 388.1320.
310.0856, found 310.0856.
4.3. Prepartion of sulfonamides 13a-k
4.2.9. Ethyl 2-diazo-2-(N-isopentyl-N-
phenylsulfamoyl)acetate (3i)
Yellow oil, 0.16 g, 95% yield (0.5 mmol scale), Rf = 0.4
1
Generally, α-bromoacetophenone (9.95 g, 50 mmol) was
added to a suspension of sodium sulphite (7.88 g, 62.5
mmol) in 75 mL of water, and the mixture was stirred for 8
h at room temperature. After removal of water under
(silica gel plate, EA:PE = 1:10, v/v). H NMR (400 MHz,
CDCl3) δ: 7.45 – 7.36 (m, 3H), 7.35 – 7.30 (m, 2H), 4.34 (q,
J
= 7.1 Hz, 2H), 3.90 (t,
J
= 7.4 Hz, 2H), 1.66 (hept,
J = 6.8
Hz, 1H), 1.39 – 1.31 (m, 5H), 0.87 (d,
J
= 6.6 Hz, 6H). 13C

8
Tetrahedron
ACCEPTED MANUSCRIPT
reduced pressure, the crude product containing sodium
chloride was obtained. To the crude product was added 50
mL of toluene, which was then removed along with water
under reduced pressure. This procedure was repeated 3
134.18, 134.15, 132.81, 129.45, 129.05, 128.96, 128.77,
58.98, 52.31, 22.24. IR (KBr, cm-1): 1678, 1343, 1162.
HRMS (ESI) calcd for C17H20NO3S+ [M+H+] m/z: 318.1158,
found 318.1164.
times
to
give
the
crude
dry
sodium
α-
4.3.4. N-Benzyl-2-oxo-N,2-diphenylethane-1-
benzoylmethanesulphonate. Then to the crude sodium α-
benzoylmethanesulphonate was added 25 mL (ca. 41 g, 27
mmol) of POCl3 and the resulting mixture was refluxed for 3
h. Then 25 mL of DCM was added, followed by addition of
a solution of secondary amine (50 mmol) in 25 mL of DCM.
The resulting solution was stirred at room temperature for
another 2 h. The mixture was transferred into a 500-mL
conical flask, and 100 mL of water and ice mixture was
added. After the pH value of the mixture was adjusted to
sulfonamide (13d)
Colorless crystals. 5.718 g, 71% yield, mp 142−
144 oC, Rf =
1
0.31 (silica gel plate, EA:PE = 1:5, v/v). H NMR (400
MHz, CDCl3) δ: 8.06 (d, = 7.4 Hz, 2H), 7.65 (t, = 7.4 Hz,
1H), 7.53 (t, = 7.7 Hz, 2H), 7.46 (d, = 7.5 Hz, 2H), 7.33
(t, = 7.4 Hz, 2H), 7.28 (d, = 7.2 Hz, 1H), 7.23 – 7.16 (m,
J
J
J
J
J
J
5H), 4.84 (s, 2H), 4.64 (s, 2H). 13C NMR (101 MHz, CDCl3)
δ: 189.8, 138.4, 136.3, 135.9, 134.4, 129.7, 129.4, 129.4,
128.9, 128.5, 128.4, 128.3, 127.7, 57.1, 57.1. IR (KBr, cm-
1): 1681, 1350, 1156. HRMS (ESI) calcd for C21H20NO3S+
[M+H+] m/z: 366.1158, found 366.1160.
6−8 with 20% sodium hydroxide, the organic phase was
partitioned and then dried over anhydrous sodium sulfate.
After removal of the solvent under reduced pressure, the
residual oil was purified on silica gel column (EA: PE =
1:10, v/v) to yield the pure sulfonamide 13
.
4.3.5. 2-Oxo-N,N,2-triphenylethanesulfonamide
(13e)
o
4.3.1. N-Methyl-2-oxo-N,2-
diphenylethanesulfonamide (13a)
Colorless crystals, 1.933 g, 56% yield, mp 112− =
113oC, Rf
Colorless crystals, 5.78 g, 66% yield, mp 173
−
175 C, Rf
=
1
0.28 (silica gel plate, EA:PE = 1:5, v/v). H NMR (400
MHz, CDCl3) δ: 8.00 (d, = 7.9 Hz, 2H), 7.60 (t, = 7.3 Hz,
1H), 7.53 – 7.44 (m, 6H), 7.35 (t, = 7.7 Hz, 4H), 7.30 –
J
J
1
0.22 (silica gel plate, EA:PE = 1:5, v/v). H NMR (400
MHz, CDCl3) δ: 8.00 (d, = 7.3 Hz, 2H), 7.63 (dd, = 7.4,
7.4 Hz, 1H), 7.55 (d, = 8.0 Hz, 2H), 7.50 (dd,
Hz, 2H), 7.41 (dd, = 7.7, 7.7 Hz, 2H), 7.32 (dd,
J
7.24 (m, 2H), 4.78 (s, 1H). 13C NMR (101 MHz, CDCl3) δ:
188.6, 140.7, 135.9, 134.3, 129.5, 129.5, 128.8, 128.6,
127.8, 58.6. IR (KBr, cm-1): 1678, 1344, 1155. HRMS (ESI)
calcd for C20H18NO3S+ [M+H+] m/z: 352.1002, found
352.1003.
J
J
J
J
= 7.7, 7.7
J = 7.4, 7.4
J
Hz, 1H), 4.57 (s, 2H), 3.37 (s, 3H). 13C NMR (101 MHz,
CDCl3) δ: 189.5, 140.7, 135.9, 134.3, 129.4, 129.3, 128.8,
127.9, 127.4, 56.6, 39.9. IR (KBr, cm-1): 1681, 1352, 1179.
HRMS (ESI) calcd for C15H16NO3S+ [M+H+] m/z: 290.0845,
found 290.0845.
4.3.6. N-Benzyl-2-oxo-2-phenyl-N-(p-
tolyl)ethanesulfonamide (13f)
Colorless crystals, 4.85 g, 51% yield, mp 114
o
−
116 C, Rf
=
1
4.3.2. 2-Oxo-N,2-diphenyl-N-
propylethanesulfonamide (13b)
0.31 (silica gel plate, EA:PE = 1:5, v/v). H NMR (400
MHz, CDCl3) δ: 8.06 (d, = 7.2 Hz, 2H), 7.64 (t, = 7.4 Hz,
1H), 7.52 (t, = 7.7 Hz, 2H), 7.33 (d, = 8.3 Hz, 2H), 7.24
– 7.17 (m, 5H), 7.12 (d, = 8.1 Hz, 2H), 4.81 (s, 2H), 4.63
J
J
This product was isolated as a mixture of two inseparable
isomers. Its 1H NMR spectrum cannot distinguish the
J
J
J
isomers, but its 13C NMR spectrum can. Colorless crystals,
(s, 2H), 2.30 (s, 3H). 13C NMR (101 MHz, CDCl3) δ: 189.9,
138.4, 136.4, 136.0, 135.7, 134.4, 130.1, 129.4, 129.4,
128.9, 128.5, 128.3, 127.6, 57.0, 57.0, 21.1. IR (KBr, cm-1):
1682, 1349, 1156. HRMS (ESI) calcd for C22H22NO3S+
[M+H+] m/z: 380.1315, found 380.1322.
o
5.32 g, 67% yield, mp 91
−
93 C, Rf = 0.33 (silica gel plate,
EA:PE = 1:5, v/v). 1H NMR (400 MHz, CDCl3) δ: 8.03 (d,
= 7.3 Hz, 2H), 7.63 (t, = 7.4 Hz, 1H), 7.59 – 7.55 (m, 2H),
7.51 (t, = 7.8 Hz, 2H), 7.46 – 7.40 (m, 2H), 7.38 – 7.33 (m,
1H), 4.55 (s, 2H), 3.64 (t, = 7.2 Hz, 2H), 1.43 (tq, = 7.4,
7.2 Hz, 2H), 0.85 (t,
= 7.4 Hz, 3H). 13C NMR (101 MHz,
J
J
J
J
J
J
4.3.7. N-Benzyl-N-(4-methoxyphenyl)-2-oxo-2-
CDCl3) δ: for one isomer, 189.68, 138.52, 135.94, 134.28,
129.53, 129.46, 129.37, 128.85, 128.32, 56.87, 54.58, 22.03,
10.72. For the other isomer, 189.65, 138.48, 135.91, 134.24,
129.50, 129.43, 129.34, 128.81, 128.29, 56.83, 54.54, 22.00,
10.68. IR (KBr, cm-1): 1680, 1349, 1168. HRMS (ESI) calcd
for C17H20NO3S+ [M+H+] m/z: 318.1158, found 318.1164.
phenylethane- sulfonamide (13g)
Colorless crystals, 8.512 g, 86% yield, mp 90
o
−
91 C, Rf
=
1
0.22 (silica gel plate, EA:PE = 1:5, v/v). H NMR (400
MHz, CDCl3) δ: 8.07 (d, = 7.2 Hz, 2H), 7.65 (t, = 7.4 Hz,
1H), 7.53 (t, = 7.7 Hz, 2H), 7.36 (d, = 8.8 Hz, 2H), 7.26
– 7.16 (m, 5H), 6.82 (d, = 8.9 Hz, 2H), 4.77 (s, 2H), 4.63
J
J
J
J
J
(s, 2H), 3.76 (s, 3H). 13C NMR (101 MHz, CDCl3) δ: 189.9,
159.3, 136.4, 135.9, 134.4, 131.0, 130.8, 129.4, 128.9,
128.6, 128.3, 127.6, 114.6, 57.3, 56.9, 55.3. IR (KBr, cm-1):
1678, 1348, 1155. HRMS (ESI) calcd for C22H22NO4S+
[M+H+] m/z: 396.1264, found 396.1268.
4.3.3. N-Isopropyl-2-oxo-N,2-
diphenylethanesulfonamide (13c)
This product was isolated as a mixture of two inseparable
isomers. Its 1H NMR spectrum cannot distinguish the
isomers, but its 13C NMR spectrum can. Colorless crystals,
5.34 g, 67% yield, mp 130
EA:PE = 1:5, v/v). 1H NMR (400 MHz, CDCl3) δ: 8.06 (d,
= 7.2 Hz, 2H), 7.62 (dd, = 7.4, 7.4 Hz, 1H), 7.50 (dd,
−
131 oC,Rf= 0.34 (silica gel plate,
4.3.8. N-Benzyl-N-(3,5-dimethylphenyl)-2-oxo-2-
phenylethanesulfonamide (13h)
Colorless crystals, 5.36 g, 55% yield, mp 136
J
o
J
J
=
−
137 C, Rf
=
1
7.7, 7.7 Hz, 2H), 7.45 – 7.38 (m, 5H), 4.60 (s, 1H), 4.33
0.28 (silica gel plate, EA:PE = 1:5, v/v). H NMR (400
MHz, CDCl3) δ: 8.06 (d, = 7.6 Hz, 2H), 7.64 (t, = 7.4 Hz,
(heptet, = 6.8 Hz, 1H), 1.13 (d,
J
J
= 6.8 Hz, 6H).13C NMR
J
J
(101 MHz, CDCl3) δ: for one isomer, 189.21, 135.89,
134.20, 134.18, 132.83, 129.47, 129.08, 128.98, 128.79,
59.01, 52.34, 22.26. For the other isomer, 189.18, 135.86,
1H), 7.52 (t,
J = 7.7 Hz, 2H), 7.24 – 7.15 (m, 5H), 7.06 (s,
2H), 6.89 (s, 0H), 4.81 (s, 2H), 4.64 (s, 2H), 2.25 (s, 6H). 13C
NMR (101 MHz, CDCl3) δ: 189.8, 139.0, 138.2, 136.6,

9
136.0, 134.3, 130.1, 129.3, 128.9, 128.4, 128.3, 127.5,
ACCEPTED MANUSCRIPT
127.0, 57.1, 57.0, 21.2. IR (KBr, cm-1): 1680, 1350, 1156.
HRMS (ESI) calcd for C23H24NO3S+ [M+H+] m/z: 394.1471,
found 394.1476.
4.4.2. 1-Diazo-2-oxo-N,2-diphenyl-N-
propylethanesulfonamide (9b)
Yellow crystals, 978 mg, 95% yield, mp 83
−
84 oC, Rf = 0.48
(silica gel plate, EA:PE = 1:5, v/v).1H NMR (400 MHz,
4.3.9. N-Benzyl-2-oxo-2-phenyl-N-(m-
CDCl3) δ: 7.64 – 7.54 (m, 3H), 7.51 – 7.44 (m, 2H), 7.43 –
tolyl)ethanesulfonamide (13i)
Colorless crystals, 6.85 g, 72% yield, mp 112
7.32 (m, 5H), 3.97 (t,
J = 7.2 Hz, 2H), 1.51 (tq, J = 7.2 Hz,
o
−
114 C, Rf
=
2H), 0.94 (t,
J
= 7.2 Hz, 3H). 13C NMR (101 MHz, CDCl3)
1
0.32 (silica gel plate, EA:PE = 1:5, v/v). H NMR (400
MHz, CDCl3) δ: 8.06 (d, = 8.3 Hz, 2H), 7.64 (t, = 6.9 Hz,
1H), 7.52 (t, = 7.3 Hz, 2H), 7.31 – 7.16 (m, 8H), 7.08 (d,
δ: 184.1, 138.3, 135.9, 132.9, 129.6, 129.0, 128.7, 128.6,
J
J
127.2, 55.5, 22.3, 10.9. IR (KBr, cm-1): 2103, 1643, 1356,
J
J
1167. HRMS (ESI) calcd for C17H18N3O3S+ [M+H+] m/z
:
= 7.2 Hz, 1H), 4.82 (s, 2H), 4.64 (s, 2H), 2.29 (s, 3H). 13C
NMR (101 MHz, CDCl3) δ: 189.8, 139.4, 138.3, 136.4,
136.0, 134.4, 130.2, 129.4, 129.2, 129.1, 128.9, 128.4,
128.3, 127.6, 126.5, 57.1, 57.0, 21.3. IR (KBr, cm-1): 1678,
1349, 1156. HRMS (ESI) calcd for C22H22NO3S+ [M+H+]
m/z: 380.1315, found 380.1321.
344.1063, found 344.1067.
4.4.3. 1-Diazo-N-isopropyl-2-oxo-N,2-
diphenylethanesulfonamide (9c)
o
Yellow crystals, 989 mg, 96% yield, mp 150
−
151 C, Rf =
0.48 (silica gel plate, EA:PE = 1:5, v/v).1H NMR (400 MHz,
CDCl3) δ: 7.68 – 7.63 (m, 2H), 7.59 (t, = 7.4 Hz, 1H), 7.49
(t, = 7.6 Hz, 2H), 7.46 – 7.38 (m, 3H), 7.25 – 7.20 (m,
2H), 4.80 (heptet,
J
4.3.10. N-Benzyl-N-(naphthalen-2-yl)-2-oxo-2-
J
phenylethanesulfonamide (13j)
Colorless crystrals, 5.33 g, 51% yield, mp 122
0.27 (silica gel plate, EA:PE = 1:5, v/v). H NMR (400
J
= 6.8 Hz, 1H), 1.16 (d, J = 6.8 Hz,
o
−
124 C, Rf
=
6H).13C NMR (101 MHz, CDCl3) δ: 183.6, 136.2, 133.9,
132.9, 132.1, 129.4, 129.2, 129.0, 127.4, 53.1, 22.3. IR
(KBr, cm-1): 2102, 1644, 1350, 1163. HRMS (ESI) calcd for
C17H18N3O3S+ [M+H+] m/z: 344.1063, found 344.1070.
1
MHz, CDCl3) δ: 8.07 (d,
– 7.76 (m, 3H), 7.64 (t,
J
J
= 7.2 Hz, 2H), 7.99 (s, 1H), 7.83
= 7.4 Hz, 1H), 7.56 – 7.45 (m,
5H), 7.27 – 7.14 (m, 5H), 4.95 (s, 2H), 4.66 (s, 2H). 13C
NMR (101 MHz, CDCl3) δ: 189.9, 136.3, 135.9, 135.8,
134.4, 133.4, 132.7, 129.4, 129.3, 128.9, 128.7, 128.5,
128.4, 128.2, 127.7, 127.6, 127.0, 126.8, 126.5, 57.1, 57.1.
IR (KBr, cm-1): 1680 1349,1156. HRMS (ESI) calcd for
C25H22NO3S+ [M+H+] m/z: 416.1315, found 416.1303.
4.4.4. N-Benzyl-1-diazo-2-oxo-N,2-
diphenylethanesulfonamide (9d)
Yellow crystals, 832 mg, 71% yield, mp 135
o
−
136 C, Rf =
1
0.39 (silica gel plate, EA:PE = 1:5, v/v). H NMR (400
MHz, CDCl3) δ: 7.76 – 7.55 (m, 3H), 7.49 (t,
J = 7.6 Hz,
2H), 7.41 – 7.17 (m, 10H), 5.18 (s, 2H). 13C NMR (101
MHz, CDCl3) δ: 184.2, 138.1, 136.6, 135.9, 133.1, 129.5,
129.1, 128.7, 128.4, 128.4, 127.7, 127.3, 57.8. IR (KBr, cm-
1): 2105, 1644, 1360, 1157. HRMS (ESI) calcd for
C21H18N3O3S+ [M+H+] m/z: 392.1063, found 392.1069.
4.3.11. N-Benzyl-N-(3,5-dimethylphenyl)-2-
oxopropane-1-sulfonamide (13k)
α-Bromoacetone was used instead of α-bromoacetophenone.
The same procedure as described in 4.3 gave the title
product. Colorless crystals, 1.24 g, 37% yield (10 mmol
o
4.4.5. 1-Diazo-2-oxo-N,N,2-
triphenylethanesulfonamide (9e)
scale), mp 102
−
103 C, Rf = 0.17 (silica gel plate, EA:PE =
1
1:5, v/v). H NMR (400 MHz, CDCl3) δ: 7.30 – 7.17 (m,
5H), 6.94 (s, 2H), 6.89 (s, 1H), 4.78 (s, 2H), 4.08 (s, 2H),
2.44 (s, 3H), 2.25 (s, 6H). 13C NMR (101 MHz, CDCl3) δ:
197.9, 139.1, 138.1, 136.2, 130.2, 128.4, 128.4, 127.7,
126.9, 61.7, 56.5, 31.5, 21.2. IR (KBr, cm-1): 1716, 1346,
o
Yellow crystals, 1.079 g, 95% yield, mp 159
0.42 (silica gel plate, EA:PE = 1:5, v/v). H NMR (400
MHz, CDCl3) δ: 7.67 – 7.52 (m, 5H), 7.49 – 7.42 (m, 4H),
−
161 C, Rf =
1
7.42 – 7.35 (m,
J = 13.4, 6.1 Hz, 4H), 7.34 – 7.27 (m, 2H).
1156. HRMS (ESI) calcd for C18H22NO3S+ [M+H+] m/z
:
13C NMR (101 MHz, CDCl3) δ: 183.1, 140.4, 135.9, 132.9,
129.5, 128.9, 128.4, 128.0, 127.2. IR (KBr, cm-1): 2112,
1651, 1359, 1164. HRMS (ESI) calcd for C20H16N3O3S+
[M+H+] m/z: 378.0907, found 378.0915.
332.1315, found 332.1315.
4.4. Preparation of diazosulfonamides 9a-k
The corresponding sulfonamide 13 (3 mmol) was dissolved
in 20 mL of dry MeCN with -nitrosulfonyl azide (698 mg,
4.4.6. N-Benzyl-1-diazo-2-oxo-2-phenyl-N-(4-
p
methylphenyl)ethanesulfonamide (9f)
Yellow crystals, 1.063 g, 87% yield, mp 126
0.36 (silica gel plate, EA:PE = 1:5, v/v). H NMR (400
o
3.06 mmol). The resulting solution was cooled to 0 C. Et3N
(455mg, 0.66 mL, 4.5 mmol) was added, and the reaction
mixture was warmed up to room temperature and stirred for
2 h. The volatiles were evaporated under reduced pressure to
yield the crude product, which was purified on silica gel
o
−
128 C, Rf =
1
MHz, CDCl3) δ: 7.66 – 7.55 (m, 3H), 7.53 – 7.44 (m, 2H),
7.33 – 7.18 (m, 5H), 7.14 (d,
J = 8.4 Hz, 2H), 7.09 (d, J =
8.4 Hz, 2H), 5.14 (s, 2H), 2.30 (s, 3H). 13C NMR (101 MHz,
CDCl3) δ: 184.2, 138.8, 136.7, 135.9, 135.4, 133.0, 130.2,
129.0, 128.5, 128.4, 127.6, 127.3, 57.9, 21.1. IR (KBr, cm-
1): 2104, 1643, 1359, 1158. HRMS (ESI) calcd for
C22H20N3O3S+ [M+H+] m/z: 406.1220, found 406.1228.
column (EA: PE = 1:10, v/v) to yield the pure product 9.
4.4.1. 1-Diazo-N-methyl-2-oxo-N,2-
diphenylethanesulfonamide (9a).
Yellow crystals, 910 mg, 96% yield, mp 124
o
−
126 C, Rf =
1
0.39 (silica gel plate, EA:PE = 1:5, v/v). H NMR (400
MHz, CDCl3) δ: 7.59 – 7.51 (m, 3H), 7.48 – 7.42 (m, 2H),
7.41 – 7.36 (m, 4H), 7.36 – 7.30 (m, 1H), 3.58 (s, 3H). 13C
NMR (101 MHz, CDCl3) δ: 184.1, 140.3, 135.8,132.7,
129.5, 129.0, 128.2, 127.2, 126.5, 40.5. IR (KBr, cm-1):
2104, 1643, 1359, 1180. HRMS (ESI) calcd for
C15H14N3O3S+ [M+H+] m/z: 316.0750, found 316.0754.

10
Tetrahedron
ACCEPTED MANUSCRIPT
2H), 5.11 (s, 2H), 3.76 (s, 3H). 13C NMR (101 MHz, CDCl3)
δ: 184.3, 159.6, 136.7, 135.9, 133.1, 130.4, 130.1, 129.1,
128.5, 128.4, 127.4, 127.3, 114.7, 58.1, 55.4. IR (KBr, cm-
1): 2104, 1641, 1358, 1157. HRMS (ESI) calcd for
C22H20N3O4S+ [M+H+] m/z: 422.1169, found 422.1174.
4.5.1. (1-Methyl-2,2-dioxido-1,3-
dihydrobenzo[c]isothiazol-3-yl)phenylmethanone
(10a)
Colorless crystals, 55 mg, 40% yield, mp 124
o
−
126 C, Rf =
1
0.20 (silica gel plate, EA:PE = 1:5, v/v). H NMR (400
MHz, CDCl3) δ: 8.15 (d, = 8.0 Hz, 2H), 7.70 (t, = 7.2 Hz,
1H), 7.58 (t, = 7.7 Hz, 2H), 7.41 (t, = 7.8 Hz, 1H), 7.19
(d, = 7.5 Hz, 1H), 7.08 (t, = 7.6 Hz, 1H), 6.82 (d, = 8.0
J
J
4.4.8. N-Benzyl-1-diazo-N-(3,5-dimethylphenyl)-2-
oxo-2-phenylethanesulfonamide (9h)
J
J
J
J
J
Hz, 1H), 6.08 (s, 1H), 3.18 (s, 3H). 13C NMR (101 MHz,
CDCl3) δ: 187.3, 141.8, 135.8, 134.7, 130.3, 129.2, 129.2,
126.7, 122.5, 118.9, 109.7, 65.5, 27.9. IR (KBr, cm-1): 1686,
1315, 1174. HRMS (ESI) calcd for C15H14NO3S+ [M+H+]
m/z: 288.0689, found 288.0685.
o
Yellow crystals, 945 mg, 75% yield, mp 115
−
117 C, Rf =
0.36 (silica gel plate, EA:PE = 1:5, v/v).1H NMR (400 MHz,
CDCl3) δ: 7.64 – 7.55 (m, 3H), 7.49 (t, = 7.6 Hz, 2H), 7.33
J
– 7.20 (m, 5H), 6.91 (s, 1H), 6.88 (s, 2H), 5.14 (s, 2H), 2.22
(s, 6H). 13C NMR (101 MHz, CDCl3) δ: 184.4, 139.2, 138.1,
136.9, 136.0, 133.0, 130.4, 129.1, 128.4, 128.2, 127.6,
127.1, 126.1, 57.8, 21.2. IR (KBr, cm-1): 2104, 1643, 1345,
4.5.2. (2,2-Dioxido-1-propyl-1,3-
1156. HRMS (ESI) calcd for C23H22N3O3S+ [M+H+] m/z
:
dihydrobenzo[c]isothiazol-3-yl)phenylmethanone
(10b)
420.1376, found 420.1384.
o
Colorless crystals, 75 mg, 47% yield, mp 163
−
163 C, Rf =
0.29 (silica gel plate, EA:PE = 1:5, v/v).1H NMR (400 MHz,
CDCl3) δ: 8.17 – 8.13 (m, 2H), 7.69 (t, = 7.4 Hz, 1H), 7.58
(t, = 7.7 Hz, 2H), 7.39 (td, = 7.9, 1.4 Hz, 1H), 7.18 (d,
= 7.5 Hz, 1H), 7.06 (t, = 7.6 Hz, 1H), 6.84 (d, = 8.1 Hz,
1H), 6.05 (s, 1H), 3.62 (dt, = 14.8, 7.2 Hz, 1H), 3.57 (dt,
= 14.8, 7.2 Hz, 1H), 1.82 (ddq, = 7.2, 7.2, 7.6Hz, 2H), 1.02
(t,
= 7.6 Hz, 2H).13C NMR (101 MHz, CDCl3) δ: 187.4,
141.2, 135.9, 134.6, 130.2, 129.2, 129.1, 126.8, 122.1,
119.0, 109.9, 65.8, 44.9, 21.5, 11.3. IR (KBr, cm-1): 1686,
1320, 1178. HRMS (ESI) calcd for C17H17NNaO3S+
[M+Na+] m/z: 338.0821, found 338.0825.
4.4.9. N-Benzyl-1-diazo-2-oxo-2-phenyl-N-(3-
methylphenyl)ethanesulfonamide(9i)
Yellow crystals, 1.104 g, 90% yield, mp 108
J
o
J
J
J
−
109 C, Rf =
0.36 (silica gel plate, EA:PE = 1:5, v/v).1H NMR (400 MHz,
CDCl3) δ: 7.63 – 7.56 (m, 3H), 7.53 – 7.45 (m, 2H), 7.30 –
7.23 (m, 5H), 7.22 – 7.16 (m, 1H), 7.11 – 7.05 (m, 3H), 5.16
(s, 2H), 2.26 (s, 3H). 13C NMR (101 MHz, CDCl3) δ: 184.3,
139.5, 138.1, 136.8, 136.0, 133.0, 129.5, 129.3, 129.3,
129.1, 128.4, 128.3, 127.6, 127.2, 125.5, 57.8, 21.2. IR
(KBr, cm-1): 2104, 1640, 1355, 1157. HRMS (ESI) calcd for
C22H20N3O3S+ [M+H+] m/z: 406.1220, found 406.1226.
J
J
J
J
J
J
4.5.3. (1-Isopropyl-2,2-dioxido-1,3-
dihydrobenzo[c]isothiazol-3-yl)phenylmethanone
(10c)
4.4.10. N-Benzyl-1-diazo-N-(naphthalen-2-yl)-2-
oxo-2-phenylethanesulfonamide (9j)
o
Yellow crystals, 1.07 g, 81% yield, mp 86
−
87 C, Rf = 0.35
o
1
Colorless crystals, 38 mg, 24% yield, mp 187
−
188 C, Rf =
(silica gel plate, EA:PE = 1:5, v/v). H NMR (400MHz,
CDCl3) δ: 7.83 – 7.70 (m, 4H), 7.62 – 7.54 (m, 3H), 7.52 –
7.43 (m, 4H), 7.38 – 7.33 (m, 1H), 7.32 – 7.27 (m, 2H), 7.27
– 7.13 (m, 4H), 5.29 (s, 2H). 13C NMR (101 MHz, CDCl3) δ:
184.3, 136.6, 135.9, 135.4, 133.4, 133.1, 132.8, 129.6 ,
129.1, 128.5, 128.4, 128.2, 128.2, 127.7, 127.7, 127.2,
127.0, 126.7, 125.7, 58.0. IR (KBr, cm-1): 2104, 1642, 1357,
0.24 (silica gel plate, EA:PE = 1:5, v/v).1H NMR (400 MHz,
CDCl3) δ: 8.14 (d, = 7.2 Hz, 2H), 7.69 (t, = 7.4 Hz, 1H),
7.57 (t, = 7.7 Hz, 2H), 7.38 (t, = 7.9 Hz, 1H), 7.17 (d,
7.6 Hz, 1H), 7.05 (t, = 7.6 Hz, 1H), 6.94 (d, = 8.0 Hz,
= 6.8 Hz, 1H), 1.55 (d,
J
J
J
J
J =
J
J
1H), 6.02 (s, 1H), 4.31 (heptet,
J
J =
7.2 Hz, 6H).13C NMR (101 MHz, CDCl3) δ: 187.4, 140.2,
136.0, 134.6, 130.0, 129.2, 129.1, 127.0, 121.9, 119.3,
111.3, 66.3, 48.6, 20.6, 19.9. IR (KBr, cm-1): 1681, 1322,
1158. HRMS (ESI) calcd for C25H20N3O3S+ [M+H+] m/z
:
442.1220, found 442.1216.
1176. HRMS (ESI) calcd for C17H18NO3S+ [M+H+] m/z
:
316.1002, found 316.0985.
4.4.11. N-Benzyl-1-diazo-N-(3,5-dimethylphenyl)-2-
oxopropanesulfonamide (9k)
4.5.4. (1-Benzyl-2,2-dioxido-1,3-
dihydrobenzo[c]isothiazol-3-yl)phenylmethanone
(10d)
Yellow crystals, 212 mg, 59% yield (1 mmol scale), mp
o
103−104 C, Rf = 0.32 (silica gel plate, EA:PE = 1:5, v/v).
1H NMR (400 MHz, CDCl3) δ: 7.30 – 7.21 (m, 5H), 6.92 (s,
1H), 6.83 (s, 2H), 4.96 (s, 2H), 2.25 (s, 6H), 2.23 (s, 3H).
13C NMR (101 MHz, CDCl3) δ: 186.7, 139.3, 138.0, 136.0,
130.5, 128.5, 128.4, 127.8, 126.1, 56.7, 26.7, 21.1. IR (KBr,
cm-1): 2105, 1666, 1361, 1157. HRMS (ESI) calcd for
C18H20N3O3S+ [M+H+] m/z: 358.1220, found 358.1224.
o
Colorless crystals, 48 mg, 26% yield, mp 176
−
178 C, Rf =
1
0.26 (silica gel plate, EA:PE = 1:5, v/v). H NMR (400
MHz, CDCl3) δ: 8.18 (d, = 7.2 Hz, 2H), 7.71 (t, = 7.4 Hz,
1H), 7.59 (t, = 7.7 Hz, 2H), 7.44 (d, = 7.3 Hz, 2H), 7.37
(t, = 7.4 Hz, 2H), 7.31 (d, = 7.2 Hz, 1H), 7.28 – 7.22 (m,
1H), 7.18 (d, = 7.6 Hz, 1H), 7.03 (t, = 7.3 Hz, 1H), 6.62
(d,
= 8.0 Hz, 1H), 6.15 (s, 1H), 4.80 (s, 2H). 13C NMR
J
J
J
J
J
J
J
J
J
4.5. General procedure for the preparation of benzo-γ-
(101 MHz, CDCl3) δ: 187.3, 141.1, 135.9, 135.0, 134.7,
130.2, 129.2, 129.2, 128.9, 127.9, 127.2, 126.6, 122.5,
118.8, 110.6, 65.8, 46.5. IR (KBr, cm-1): 1696, 1327, 1157.
sulfonamides 10a-k
To a suspension of Cu(acac)2 (2 mol%, 13 mg, 0.01 mmol)
in 10 mL of toluene, was added the corresponding
diazosulfonamide
HRMS (ESI) calcd for C21H17NNaO3S+ [M+Na+] m/z
:
9 (0.5 mmol), and the mixture was
386.0821, found 386.0815.
refluxed for 9 h. The volatiles were removed under reduced
pressure and the crude reaction mixture was purified on a
silica gel column (PE : EA = 10 :1, v/v) to afford the desired
4.5.5. (2,2-Dioxido-1-phenyl-1,3-
dihydrobenzo[c]isothiazol-3-yl)phenylmethanone
(10e)
product 10
.

11
Colorless crystals, 103 mg, 59% yield, mp 149
−
150 oC, Rf =
(t,
J
= 7.4 Hz, 2H), 7.31 (t,
J
= 6.9 Hz, 1H), 7.06 (d,
J =
ACCEPTED MANUSCRIPT
1
0.26 (silica gel plate, EA:PE = 1:5, v/v). H NMR (400
MHz, CDCl3) δ: 8.17 (d, = 7.6 Hz, 2H), 7.68 (t, = 7.4 Hz,
1H), 7.57 (t, = 7.7 Hz, 2H), 7.53 – 7.40 (m, 5H), 7.32 (t,
= 7.8 Hz, 1H), 7.27 – 7.21 (m, 1H), 7.11 (t, = 7.6 Hz, 1H),
6.69 (d,
= 8.1 Hz, 1H), 6.22 (s, 1H). 13C NMR (101 MHz,
7.7 Hz, 1H), 6.85 (d, J = 7.7 Hz, 1H), 6.45 (s, 1H), 6.11 (s,
J
J
1H), 4.78 (s, 2H), 2.27 (s, 3H). 13C NMR (101 MHz, CDCl3)
δ: 187.5, 141.1, 140.7, 135.9, 135.3, 134.6, 129.2, 129.2,
128.9, 127.9, 127.1, 126.3, 123.3, 115.9, 111.3, 65.7, 46.5,
21.9. IR (KBr, cm-1): 1692, 1328, 1175. HRMS (ESI) calcd
for C22H20NO3S+ [M+H+] m/z: 378.1158, found 378.1152.
J
J
J
J
CDCl3) δ: 187.4, 142.0, 135.8, 134.7, 133.4, 130.2, 130.0,
129.22, 129.16, 128.4, 126.8, 123.0, 119.1, 111.8, 66.0. IR
(KBr, cm-1): 1692, 1337, 1161. HRMS (ESI) calcd for
C20H16NO3S+ [M+H+] m/z: 350.0845, found 350.0838.
4.5.10. (3-Benzyl-2,2-dioxido-1,3-
dihydronaphtho[2,1-c]isothiazol-1-
yl)phenylmethanone (10j)
o
4.5.6. (1-Benzyl-5-methyl-2,2-dioxido-1,3-
dihydrobenzo[c]isothiazol-3-yl)phenylmethanone
(10f)
Colorless crystals, 61 mg. 30% yield, mp 195
−
197 C, Rf =
1
0.26 (silica gel plate, EA:PE = 1:5, v/v). H NMR (400
MHz, CDCl3) δ: 8.23 (d, = 7.6 Hz, 2H), 7.92 – 7.77 (m,
2H), 7.74 (t, = 7.4 Hz, 1H), 7.63 (t, = 7.7 Hz, 2H), 7.48
(d, = 7.3 Hz, 2H), 7.44 – 7.28 (m, 5H), 7.20 (d, = 8.0 Hz,
1H), 6.96 – 6.89 (m, 1H), 6.49 (s, 1H), 4.93 (d, = 16.7 Hz,
1H), 4.88 (d,
= 16.9 Hz, 1H). 13C NMR (101 MHz, CDCl3)
J
Colorless crystals, 89 mg, 47% yield, mp 153
−
155 oC, Rf =
J
J
1
0.29 (silica gel plate, EA:PE = 1:5, v/v). H NMR (400
MHz, CDCl3) δ: 8.17 (d, = 7.3 Hz, 2H), 7.70 (t, = 7.4 Hz,
1H), 7.59 (t, = 7.7 Hz, 2H), 7.43 (d, = 7.3 Hz, 2H), 7.36
(t, = 7.4 Hz, 2H), 7.30 (t, = 7.2 Hz, 1H), 7.04 (d, = 8.3
Hz, 1H), 7.00 (s, 1H), 6.52 (d, = 8.2 Hz, 1H), 6.11 (s, 1H),
4.79 (d, = 16.6 Hz, 1H), 4.75 (d, = 16.6 Hz, 1H), 2.27 (s,
J
J
J
J
J
J
J
J
J
J
J
δ: 187.4, 139.9, 135.9, 135.4, 134.7, 131.3, 129.8, 129.5,
129.3, 129.3, 129.3, 128.9, 128.3, 128.0, 127.2, 124.5,
122.2, 112.5, 111.8, 65.3, 47.5. IR (KBr, cm-1): 1678, 1343,
J
J
J
3H). 13C NMR (101 MHz, CDCl3) δ: 187.6, 138.9, 135.9,
135.2, 134.7, 132.3, 130.7, 129.2, 129.2, 128.8, 127.9,
127.2, 127.0, 119.0, 110.8, 65.9, 46.9, 20.9. IR (KBr, cm-1):
1692, 1328, 1175. HRMS (ESI) calcd for C22H19NNaO3S+
[M+Na+] m/z: 400.0978, found 400.0974.
1180. HRMS (ESI) calcd for C25H19NNaO3S+ [M+Na+] m/z
:
436.0978, found 436.0972.
4.5.11. 1-(1-Benzyl-4,6-dimethyl-2,2-dioxido-1,3-
dihydrobenzo[c]isothiazol-3-yl)ethan-1-one (10k)
Colorless crystals, 73 mg, 37% yield, mp 128
o
−
129 C, Rf =
1
4.5.7. (1-Benzyl-5-methoxy-2,2-dioxido-1,3-
dihydrobenzo[c]isothiazol-3-yl)phenylmethanone
(10g)
0.35 (silica gel plate, EA:PE = 1:5, v/v). H NMR (400
MHz, CDCl3) δ: 7.42 (d, = 7.2 Hz, 2H), 7.40 – 7.35 (m,
2H), 7.34 – 7.29 (m, 1H), 6.67 (s, 1H), 6.30 (s, 1H), 5.05 (s,
J
o
Colorless crystals, 36 mg, 18% yield, mp 150
−
151 C, Rf =
1H), 4.90 (d,
J = 16.5 Hz, 1H), 4.61 (d, J = 16.5 Hz, 1H),
1
2.29 (s, 3H), 2.23 (s, 3H), 2.12 (s, 3H). 13C NMR (101 MHz,
CDCl3) δ: 195.6, 140.9, 140.8, 135.6, 135.1, 128.9, 128.0,
127.2, 124.9, 114.1, 108.7, 70.6, 45.8, 27.8, 21.8, 18.7. IR
(KBr, cm-1): 1729, 1327, 1185. HRMS (ESI) calcd for
C18H20NO3S+ [M+H+] m/z: 330.1158, found 330.1161.
0.18 (silica gel plate, EA:PE = 1:5, v/v). H NMR (400
MHz, CDCl3) δ: 8.17 (d, = 7.4 Hz, 2H), 7.71 (t, = 7.4 Hz,
1H), 7.60 (t, = 7.7 Hz, 2H), 7.44 (d, = 7.4 Hz, 2H), 7.37
(t, = 7.4 Hz, 2H), 7.33 – 7.28 (m, 1H), 6.83 – 6.73 (m,
2H), 6.56 (d, = 8.7 Hz, 1H), 6.10 (s, 1H), 4.80 (d, = 16.3
Hz, 1H), 4.72 (d,
= 16.3 Hz, 1H), 3.73 (s, 3H). 13C NMR
J
J
J
J
J
J
J
J
(101 MHz, CDCl3) δ: 187.5, 155.6, 135.8, 135.4, 135.1,
134.7, 129.3, 129.2, 128.9, 127.9, 127.3, 120.8, 115.6,
112.7, 112.6, 66.2, 55.7, 48.1. IR (KBr, cm-1): 1693, 1327,
Acknowledgments
1179. HRMS (ESI) calcd for C22H20NO4S+ [M+H+] m/z
:
This work was supported by the National Natural Science
Foundation of China (No. 21572017 for J. X. Xu, and No.
21602010 for Z. H. Yang), the BUCT Fund for Discipline
Construction and Development (Project No. XK1533), and the
China Postdoctoral Science Foundation (No. 2016M600900).
394.1108, found 394.1102.
4.5.8. (1-Benzyl-4,6-dimethyl-2,2-dioxido-1,3-
dihydrobenzo[c]isothiazol-3-yl)phenylmethanone
(10h)
o
Colorless crystals, 62 mg, 32% yield, mp 187
−
187 C, Rf =
Supplementary Material
1
0.35 (silica gel plate, EA:PE = 1:5, v/v). H NMR (400
MHz, CDCl3) δ: 8.15 (d, = 7.6 Hz, 2H), 7.69 (t, = 7.4 Hz,
1H), 7.58 (t, = 7.7 Hz, 2H), 7.42 (d, = 7.3 Hz, 2H), 7.36
(t, = 7.5 Hz, 2H), 7.29 (t, = 7.2 Hz, 1H), 6.67 (s, 1H),
6.29 (s, 1H), 6.06 (s, 1H), 4.82 (d, = 16.7 Hz, 1H), 4.71 (d,
= 16.7 Hz, 1H), 2.22 (s, 3H), 2.03 (s, 3H). 13C NMR (101
J
J
1H and 13C NMR spectra of sulfonamides 12a-m and 13a-k,
diazosulfonamides 3a-m and 9a-k, and products 10a-k. The
Supplementary Material is available free of charge on http://dx.
doi: 10.1021/xxxxxx.
J
J
J
J
J
J
MHz, CDCl3) δ: 187.5, 141.2, 140.4, 136.0, 135.3, 135.1,
134.5, 129.2, 129.1, 128.8, 127.7, 127.0, 124.9, 115.5,
108.9, 65.0, 46.6, 21.8, 19.2. IR (KBr, cm-1): 1692, 1325,
References and notes
1. For selected reviews, see: (a) Cardin, D. J.; Cetinkaya, B.; Lappert, M.
F. Chem. Rev. 1972, 72, 545−574. (b) Padwa, A.; Krunpe, K. E.
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Davies, H. M. L.; Manning, J. R. Nature 2008, 451, 417−424. (g)
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1170. HRMS (ESI) calcd for C23H21NNaO3S+ [M+Na+] m/z
:
414.1134, found 414.1128.
4.5.9. (1-Benzyl-6-methyl-2,2-dioxido-1,3-
dihydrobenzo[c]isothiazol-3-
yl)phenylmethanone(10i)
Colorless crystals, 57 mg, 30% yield, mp 156
o
−
158 C, Rf =
1
0.29 (silica gel plate, EA:PE = 1:5, v/v). H NMR (400
MHz, CDCl3) δ: 8.17 (d, = 7.4 Hz, 2H), 7.70 (t, = 7.4 Hz,
1H), 7.58 (t, = 7.7 Hz, 2H), 7.44 (d, = 7.4 Hz, 2H), 7.38
J
J
J
J

12
Tetrahedron
ACCEPTED MANUSCRIPT
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9. See Table 1. Actually, much more conditions (catalysts, solvents,
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12. Diazo transfer was attempted in acetonitrile with
trifluoromethanesulfony azide (TfN3), 4-toluenesulfonyl azide (TsN3),
methanesulfony azide (MsN3), 4-nitrobenzenesulfonyl azide (NsN3), 4-
acetamidobenzenesulfonyl azide (p-ABSA) with different bases such
Et3N, DBU, Cs2CO3, K2CO3, NaH, imidazole, DABCO, i-Pr2NEt, and
Pyridine.
13. For the synthetic methods to benzo-γ-sultams, see the references
cited in ref. 8.
14. Antilla, J. C.; Buchwald, S. L. Org. Lett. 2001, 3, 2077−2079.