Copper-catalyzed N–H insertion reactions from sulfoxonium ylides

Article abstract of DOI:10.1016/j.tet.2020.131313

The first use of copper(II) as an efficient catalyst for N–H insertion reactions between anilines and α-carbonyl sulfoxonium ylides is described. Products, 39 arylglycine derivatives, were obtained in yields up to 97% employing a simple and fast experimental procedure.

Full text of DOI:10.1016/j.tet.2020.131313

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Copper-catalyzed N–H insertion reactions from sulfoxonium ylides
Lucas G. Furniel, Antonio C.B. Burtoloso
PII:
S0040-4020(20)30467-1
https://doi.org/10.1016/j.tet.2020.131313
TET 131313
DOI:
Reference:
To appear in: Tetrahedron
Received Date: 31 March 2020
Revised Date: 22 May 2020
Accepted Date: 25 May 2020
Please cite this article as: Furniel LG, Burtoloso ACB, Copper-catalyzed N–H insertion reactions from
sulfoxonium ylides, Tetrahedron (2020), doi: https://doi.org/10.1016/j.tet.2020.131313.
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Copper-catalyzed N-H insertion reactions
from sulfoxonium ylides
Leave this area blank for abstract info.
Lucas G. Furniel, Antonio C.B. Burtoloso*
São Carlos Institute of Chemistry, University of São Paulo, São Carlos, SP, CEP 13560-970, Brazil

1
Tetrahedron
journal homepage: www.elsevier.com
Copper-catalyzed N-H insertion reactions from sulfoxonium ylides
Lucas G. Furniel, Antonio C.B. Burtoloso
São Carlos Institute of Chemistry, University of São Paulo, São Carlos, SP, CEP 13560-970, Brazil
ARTICLE INFO
ABSTRACT
Article history:
Received
Received in revised form
Accepted
The first use of copper(II) as an efficient catalyst for N-H insertion reactions between anilines
and α-carbonyl sulfoxonium ylides is described. Products, 39 arylglycine derivatives, were
obtained in yields up to 97% employing a simple and fast experimental procedure.
Available online
2009 Elsevier Ltd. All rights reserved
.
Keywords:
Sulfoxonium ylides; N-H insertion; Metal-carbene;
Arylglycine derivatives; Copper catalysis.
1. Introduction
demonstrated that Au is also a competent catalyst in these X-H
insertions (Scheme 1c).16 Although all these contributions
showed to be efficient for carrying-out N-H insertion reactions
from sulfoxonium ylides, they still have some drawbacks in the
experimental procedure such as the need of expensive
catalysts,14-16 degassed solvents15,16 and/or very slow addition of
the substrate.14 Despite these advances and some recent work on
X-H insertions from α-carbonyl sulfoxonium ylides,17–24 there is
still no report of such reactions catalyzed by cheap and abundant
metals. Herein we describe the first use of copper(II) as an
efficient catalyst for N-H insertion reactions with α-carbonyl
sulfoxonium ylides.
The synthesis of unnatural amino acids and its derivatives is
of great importance in chemistry and biology, due to the relevant
biological activities that these compounds exhibit.1–3 In
particular, arylglycine and N-aryl amino acid derivatives are
interesting scaffolds that are encountered in medicinal important
compounds, such as vancomycin (antibiotic), cefprozil
(antibiotic) and Indolactam-V (protein kinase C activator).4–6 One
of the most straightforward ways to prepare unnatural amino
acids and other nitrogen containing compounds is using metal-
catalyzed N-H insertion reactions with α-carbonyl diazo
compounds as metal-carbene precursors.7 Although their
versatility as intermediates in organic synthesis is undeniable,
some diazo compounds present drawbacks related to the inherent
reactivity of the diazo group, such as thermal instability, release
of N2 gas and toxicity of diazomethane (when used in its
synthesis).8–10 Recently, sulfoxonium ylides have been employed
as surrogates to diazo compounds, offering advantages since they
are usually crystalline, bench stable, more thermally stable than
diazo counterparts and do not release gas over the course of the
reaction.11–13
In spite of being known since 1930s, the first use of
sulfoxonium ylides in metal catalyzed X-H insertion was only in
1993, by Baldwin and coworkers, using a Rh catalyst (scheme
1a).14 The authors also evaluated copper sources, a much less-
expensive alternative, but without success. Sixteen years later,
Mangion and coworkers from Merck reported an Ir catalyzed X-
H insertion with α-carbonyl sulfoxonium ylides, stablishing the
first general catalyst for carbene reactions using sulfoxonium
ylides (Scheme 1b).15 One year later, the same group
Scheme 1. Metal catalyzed X-H insertion with sulfoxonium ylides.
———
Corresponding author. Tel.: +55 16 3373 8641; fax: +55 16 3373 9952; e-mail adresses: antonio@iqsc.usp.br, (A.C.B. Burtoloso).

2
Tetrahedron
2. Results and discussion
We commenced our studies using common copper sources
employed in decomposition of diazo compounds into their
respective metal-carbenes.7 In our very first entry we were
delighted to detect the N-H insertion product in 29% yield (NMR
analysis). Using CuBr as catalyst resulted in little improvement
of the yield (entry 2). However, using Cu(OTf)2 instead of CuBr,
resulted in a drastic improvement of the yield (91%, entry 3).
Reducing aniline loading from 2 eq to 1,2 eq didn’t compromised
the yield of 3, but slowed the reaction (38 h, entry 4). Reducing
the catalyst loading to 5 mol% slowed the reaction even further,
but still provided a high yield (88%, entry 5). Other common
copper sources such as Cu(OAc)2 and CuSO4 failed to deliver the
product in acceptable yields (entries 6 and 7). Changing the
solvent to DMF also inhibited formation of the product (entry 8).
Toluene was also evaluated, but sulfoxonium ylide 1 was not
soluble in this solvent at room temperature, failing to furnish the
product (entries 9-10). To overcome this problem entries 9 and
10 were repeated at 60ºC, resulting in the formation of the
product in a much lesser time as well as in 87 and 91% yield,
respectively. Cu(hfacac)2 was the catalyst of choice, since it
provided insertion product 3 in just 15 minutes. No solvent
degassing was needed for these catalytic systems.
Table 1. Optimization of reaction conditions for Cu catalyzed N-H insertion.
Entrya Aniline Cu catalyst
(equiv)
Solvent time
Yield
3ab
aReaction conditions: 1 (0,15 mmol), aniline (0,18 mmol), catalyst
b
(0,0075 mmol), in 1,5 mL of solvent, 60ºC for 30 min, under argon. 60 min
1c
2,0
2,0
2,0
1,2
1,2
1,2
1,2
1,2
1,2
1,2
1,2
1,2
CuCl
CH2Cl2 25 h
CH2Cl2 25 h
CH2Cl2 19 h
CH2Cl2 38 h
CH2Cl2 48 h
29%
44%
91%
85%
88%
trace
trace
trace
trace
trace
87%
reaction. All yields correspond to the isolated product.
2c
CuBr
Scheme 2. Aniline scope in the N-H insertion reaction.
3c
Cu(OTf)2
Cu(OTf)2
Cu(OTf)2
4c
We started the aniline scope by analyzing the effect of methyl
substituents in the aromatic ring. N-H insertion products were
obtained in high yields independently of the position of the
methyl groups (4-6). Surprisingly, o-toluidine furnished the
highest yield, neglecting the effect of a possible steric hindrance.
Even 2,4,6-trimethylaniline afforded product in 89% yield (7).
Next, anilines with the strong electron releasing group -OMe
were evaluated. N-H insertion products 8-12 were provided in
high yields for all 3 patterns of substitution (8-10) and also for
disubstituted anilines, in a somewhat lesser yield (11-12).
Interestingly, benzene-1,3-diamine also afforded mono-insertion
product in respectable yield (13, 52%). Strong electron
withdrawing groups such as -NO2 and -CF3 were also examined.
Para and meta substituted nitroanilines resulted in N-H insertion
products in high yields (14-15), though ortho-nitroaniline
delivered the product in only 18% yield (16). This might be due
to an enhanced electron withdrawing inductive effect with the
nitro group closer to the amino group, when comparing to p-
nitroaniline, for example, which deactivates this aniline even
more as a nucleophile. Mono and di substituted anilines
containing the -CF3 group were also well tolerated, giving rise to
products 17-19 in yields in the 68-86% range. Halogen
substitution in anilines also did not cause pronounced variation in
yield (81-86%, 20-24). Anilines substituted with both electron
5d
6d
Cu(OAc)2.H2O CH2Cl2 48 h
7d
CuSO4.5H2O
Cu(OTf)2
CH2Cl2 48 h
DMF 48 h
8d
9d
Cu(OTf)2
toluene 48 h
toluene 48 h
toluene 5 h
10d
11d,e
12d,e
Cu(hfacac)2
g
Cu(OTf)2
Cu(hfacac)2
toluene 15 min 91%f
aReaction conditions: 1 (0,1 mmol), aniline (0,2 or 0,12 mmol), catalyst
(0.005 or 0.01 mmol), in 1,0 mL of solvent, under argon at 25o C. byield
calculated by quantitative nmr analysis with hexamethylbenzene as internal
stadand. c 10 mol% of the catalyst. d 5 mol% of the catalyst. e performed at 60o
f
g
C.
isolated yield, reaction on 0,15 mmol scale of 1.
hfacac =
hexafluoroacetylacetone.
After finding the optimal reaction conditions we began to
explore the substrate scope, in order to evaluate aniline electronic
and steric effects in product formation (Scheme 2).

3
releasing and electron withdrawing groups resulted in products
25 and 26 within the same yield range as other substituents
already shown (77-81%). Lastly, 1-naphtylamine and N-
methylaniline were also suitable nucleophiles for the reaction,
giving 27 and 28 in good yields (71 and 87%, respectively).
However, when the same reaction was repeated at 150ºC under
MW irradiation,21 products 50 and 51 were obtained, albeit in
lower yields (18 and 32%, respectively).
A mechanism that is in accordance with our results, with
studies on metal-carbenes from sulfur ylides25–28 and with
previously proposed X-H insertion reactions with sulfoxonium
ylides16 is shown in Fig. 1.
We next turned our focus to evaluate the performance of
different sulfoxonium ylides under the reaction conditions, as
depicted in Scheme 3.
Fig 1. Proposed mechanism for the N-H insertion reaction.
The first step is the formation of metal-carbene (A) from the
sulfoxonium ylide, with loss of DMSO. Next, this electrophilic
metal-carbene is attacked by aniline’s nitrogen lone pair,
generating intermediate B. This intermediate evolves to metal-
associated ylide (C), which can be in equilibrium with free ylide
(D). The species distribution of this equilibrium is highly
sensitive to both substrate and catalyst nature.29–31 Both C and D
can be subjected to the assisted [1,2]-proton shift to furnish the
N-H insertion product and regenerate the catalyst.
aReaction conditions: 1 (0,15 mmol), aniline (0,18 mmol), catalyst
(0,0075 mmol), in 1,5 mL of solvent, 60ºC for 30 min, under argon. b3h
reaction. cno reaction at 60ºC. Yields of 50 and 51 of reaction at 150ºC, for 30
min, under MW irradiation. All yields correspond to the isolated product.
3. Conclusions
In summary, the first copper catalyzed N-H insertion
procedure with α-carbonyl sulfoxonium ylides is presented. 39
arylglycine and N-aryl amino acids derivatives were prepared via
N-H insertion into a metal-carbene intermediate, mostly in high
yields with a simple, fast, highly substituent tolerant and
straightforward procedure. The asymmetric version of this
methodology is already been studied in our research group.
Scheme 3. Sulfoxonium ylide scope in the N-H insertion reaction.
We started to study sulfoxonium ylide scope by analyzing
variations in the ester moiety. Ester with electron withdrawing
group (38) or bulky group (41) furnished the N-H insertion
products with aniline in good yields (72-84%). Esters with
aromatic rings, on the other hand, provided products 39 and 40,
only in moderate yields (57 and 53%, respectively). Alkyl and
halogen substituted ylides proceeded smoothly supplying
products 42-46 in good yields with both aniline and 4-
bromoaniline (70-86%). However, sulfoxonium ylide with the
electron withdrawing acetyl group gave rise to products 48 and
49 in lower yields (24-39%). These reactions provided several
by-products as judged by TLC analysis, which explain the low
isolated yields for 48 and 49 (probably imine formation from the
acetyl group, diminishing the amount of aniline available to react
with the formed metal carbene; accumulated metal carbene can
also give rise to other reactions as well). When the aryl group α
to the ylide was replaced by a methyl group, the reaction did not
occur at 60ºC (only starting materials by TLC analysis).
4. Experimental Section
4.1. General methods
All solvents were dried and distilled prior to use by standard
procedures. Reagents were purchased at the highest commercial
quality and used without further purification, unless stated
otherwise. Reactions were monitored by thin layer
chromatography (TLC), carried out using silica gel 60 F254
precoated plates, with UV light (254 nm) as visualizing agent,
potassium permanganate in aqueous KOH and ethanolic vanilin
for staining. Flash column chromatography was performed using
silica gel 60 (200-400 Mesh) or using Biotage IsoleraTM Prime

4
Tetrahedron
4.1.3. Phenyl 2-(dimethyl(oxo)-λ6 -sulfanylidene)
(Snap Ultra 10g). Unless stated otherwise, all yields refer to
acetate (52)
isolated products after purification by flash column
chromatography. The solvent mixtures employed in TLC analysis
and in flash column chromatography purifications are reported as
volume by volume and in percentages. Proton nuclear magnetic
resonance (1H NMR) spectra were recorded using 400 and 500
Prepared from phenyl chloroformate (1.06 g, 6.8 mmol),
potassium tert-butoxide (3.05 g, 27.2 mmol, 4.0 equiv) and
trimethylsulfoxonium iodide (4.49 g, 20.4 mmol; 3.0 equiv).
Yield: 60% (863.7 mg, 4.07 mmol). White solid. Rf = 0.44
(AcOEt). 1H NMR (500 MHz, CDCl3): δ 7.34 (m, 2H), 7.16 (t, J
= 7.4 Hz, 1H), 7.10 (d, J = 7.9 Hz, 2H), 4.15 (s, 1H), 3.40 (s,
6H). 13C NMR (126 MHz, CDCl3) δ 165.7, 151.5, 129.3, 125.0,
122.3, 55.7, 42.4. In good agreement with previously reported
data.13
1
MHz instrument. For H NMR spectra, chemical shifts (d) are
referenced from TMS (0.00 ppm). Coupling constants (J) are
reported in Hz. For multiplicities the following abbreviations
were used: s, singlet; d, doublet; t, triplet; q, quartet; m, multiplet;
dd, double doublet; br s, broad singlet; t, triplet; dt, double triplet;
ddd, doublet of doublet of doublets. Carbon nuclear magnetic
resonance (13C NMR) spectra were recorded using a NMR
spectrometer at 100 or 125 MHz. For 13C NMR spectra, chemical
4.1.4. Benzyl 2-(dimethyl(oxo)-λ6 -sulfanylidene)
acetate (53)
Prepared from benzyl chloroformate (1.16 g, 6.8 mmol),
potassium tert-butoxide (3.05 g, 27.2 mmol, 4.0 equiv) and
trimethylsulfoxonium iodide (4.49 g, 20.4 mmol; 3.0 equiv).
Yield: 55% (853.8 mg, 3.77 mmol). Yellow solid. Rf = 0.45 (2%
MeOH/AcOEt). 1H NMR (500 MHz, CDCl3): δ 7.40 – 7.25 (m,
5H), 5.10 (s, 2H), 4.02 (s, 1H), 3.36 (s, 6H). 13C NMR (126 MHz,
CDCl3) δ 166.9, 137.5, 128.5, 128.0, 127.8, 64.7, 55.6, 42.5.
HRMS (FTMS+pESI) m/z: calculated for C11H14O3S [M+H]+
227.07364; found 227.07332.
shifts (
d
) are given from CDCl (77.16 ppm). High resolution
3
mass spectra (HRMS) were recorded using electron spray
ionization (ESI) (Hybrid linear ion trap orbitrap FT-MS and
QqTOF/MS-Microtof-QII models). Microwave experiments were
performed in an Anton Paar Monomode 300 system allowing
temperatures from 0 to 300 °C (measured with a Ruby
thermometer), powers from 0 to 850 W, and pressures from 0 to
30 bar. Experiments were performed in sealed glass vials (4−30
mL) equipped a snap cap and a silicon septum.
4.1.5. t-Butyl 2-(dimethyl(oxo)-λ6 -sulfanylidene)
acetate (54)
4.1.1. General procedure for preparation of α-ester
sulfoxonium ylides
Prepared from di-tert-butyl dicarbonate (1.48 g, 6.8 mmol),
potassium tert-butoxide (3.05 g, 27.2 mmol, 4.0 equiv) and
trimethylsulfoxonium iodide (4.49 g, 20.4 mmol; 3.0 equiv).
Yield: 67% (881.1 mg, 4.58 mmol). White solid. Rf = 0.31 (2%
MeOH/AcOEt). 1H NMR (500 MHz, CDCl3) δ 3.86 (s, 1H), 3.36
(s, 6H), 1.47 (s, 9H). 13C NMR (101 MHz, CDCl3) δ 167.2, 78.7,
56.5, 42.5, 29.0. HRMS (FTMS+pESI) m/z: calculated for
C8H16O3S [M+H]+ 193.08929; found 193.08946.
α-ester sulfoxonium ylides were synthesized through a
modified procedure.13,32 In a 125 mL flame-dried round bottom
flask attached to a reflux condenser, under argon atmosphere,
potassium tert-butoxide (4.0 equiv) and anhydrous THF (1 mL/
mmol of t-BuOK) were added. Then, trimethylsulfoxonium
iodide (3.0 equiv) or triethylsulfoxonium chloride (3.0 equiv)
was added in one portion. The suspension was heated at reflux
for 2 hours. After this time, the mixture was cooled at 0 °C,
followed by slow addition of the appropriate chloroformate or
carbonate (1.0 equiv). The reaction mixture temperature was
naturally increased to room temperature and this mixture stirred
for additional 15 hours.
4.1.6. methyl 2-(dimethyl(oxo)- λ6 -
sulfaneylidene)acetate (55)
Prepared from dimethyl carbonate (2.70 g, 30.0 mmol),
potassium tert-butoxide (13.4 g, 60.0 mmol, 4.0 equiv) and and
trimethylsulfoxonium iodide (19.8 g, 9.0 mmol; 3.0 equiv).
Yield: 48% (2.14 g, 14.3 mmol). White solid. Rf = 0.33 (5%
For compounds 37 and 55: Then, the mixture was filtered
through a plug of celite (elution DCM). After evaporation of all
volatiles, purification by flash chromatography (100% ethyl
acetate).
1
MeOH/AcOEt). H NMR (500 MHz, CDCl3) δ 3.96 (s, 1H),
3.63 (s, 3H), 3.39 (s, 6H). 13C NMR (126 MHz, CDCl3) δ
167.6, 55.2, 50.2, 42.4. In good agreement with previously
reported data.32
For compounds 52-54: Then, the solvent was removed on a
rotary evaporator. After that, 70 mL of water was added and the
product extracted with a 3:1 CH2Cl2:i-PrOH mixture (8 x 20 mL).
The organic phase was washed with water (3 x 10 mL), dried
over Na2SO4, and the solvent was removed on a rotary
evaporator. The crude material was purified by crystallization in
the minimal amount of hot AcOEt (10-15 mL), followed by slow
addition of 15 mL of hexanes and further filtration collecting the
precipitated solid. For compound 53 it was not possible to obtain
a precipitate, therefore after evaporation of all volatiles, the crude
mixture was purified by flash chromatography (100% ethyl
acetate).
4.2. General procedures for preparation of α-aryl substituted
α-ester sulfoxonium ylides
General procedure A: A modified procedure was used.19 In a
125 mL round bottomed flask were added Rh2(OAc)4 (39.7 mg,
0.09 mmol, 1 mol %) and dry DMSO (30 mL). The system was
closed, placed under argon atmosphere and heated to 70ºC in oil
bath. To this solution, was slowly added a solution of methyl 2-
diazo-2-phenylacetate34 (1.58 g, 9.0 mmol, 1.0 eq) in dry DMSO
(30 mL) over 15h (syringe pump). The reaction was further
stirred at 70ºC for 6h. After completion, the reaction was cooled
to r.t., diluted with AcOEt (200 mL) and the organic phase was
washed with water (6 x 20 mL) until there was no more DMSO
in the organic phase (analysis by TLC). The organic phase was
then dried with MgSO4 and evaporated. The crude material was
purified by crystallization in the minimal amount of hot AcOEt
(10-15 mL), followed by slow addition of 30 mL of hexanes and
further filtration collecting the precipitated solid.
4.1.2. methyl 2-(diethyl(oxo)-λ6-
sulfaneylidene)propanoate (37)
Prepared from dimethyl carbonate (252 mg, 2.8 mmol),
potassium tert-butoxide (1.26 g, 11.2 mmol, 4.0 equiv) and
triethylsulfoxonium chloride (1.44 g, 8.4 mmol; 3.0 equiv).33
Yield: 99% (533.8 mg, 2.78 mmol). Oily white solid. Rf = 0.52
1
(5% MeOH/AcOEt). H NMR (500 MHz, CDCl3) δ 3.91 (br,
General procedure B32: To a 10 mL round-bottomed flask
containing a magnetic stirrer and fitted with a Teflon cap, the
respective α-ester sulfoxonium ylide (0.6 mmol, 1.0 equiv),
2H), 3.61 (s, 1H), 3.19 (dq, J = 14.2, 7.2 Hz, 2H), 1.82 (s, 3H),
1.31 (s, 6H). 13C NMR (101 MHz, CDCl3) δ 167.0, 50.0, 46.2,
44.3, 8.0, 5.0. HRMS (ESI+qTOF) m/z: calculated for C8H16O3S
[M+H]+ 193.08929; found 193.0898.

5
activated molecular sieves 4Å powder (115 mg), CsF (273 mg,
1.8 mmol, 3.0 equiv), and dry MeCN (5.0 mL) were added. The
reaction mixture was heated to 65ºC and the first portion of 2-
(trimethylsilyl)phenyl trifluoromethanesulfonate (91.7 mg, 75
μL, 0.3 mmol, 0.5 eq) was added. Two more portions of the
aryne precursor were added at 1h and 2h hours of reaction,
totalizing 1.5 eq. One hour after the last addition (3 hours of
reaction), the organic solvent was removed into rotary evaporator
and the crude product purified by flash chromatography,
employing the silica gel and mixtures of 0.5 to 2% of MeOH in
CHCl3.
General procedure C: A modified procedure was used.13 A 5
mL round-bottomed flask containing a magnetic stirrer was
charged with XPhos (52.4 mg, 0.11 mmol, 0.11 equiv), Pd2dba3
(45.8 mg, 0.05 mmol, 0.05 equiv) and Cs2CO3 (358.4 mg, 1.1
mmol, 1.1 equiv) under argon. Next, dry MeCN (3.0 mL) was
added and the solution was stirred at r.t. for 10 min. In a separate
flask were added α-ester sulfoxonium ylide 55 (150.2 mg, 1.0
mmol, 1.0 eq), aryl bromide (1.5 mmol, 1.5 eq) and dry MeCN
(3.0 mL) under argon. The ylide solution was then added to the
catalyst solution and the reaction was placed in preheated oil bath
(75ºC) and stirred at this temperature for 15h. The crude mixture
was then filtered over a plug of silica at room temperature using a
DCM/MeOH (85/15) mixture to transfer all the material and for
rinsing. After evaporation of all volatiles, purification by flash
chromatography using AcOEt/hexanes as eluent (50% to 100%)
(FTMS+pESI) m/z: calculated for C17H18O3S [M+H]+
303.10494; found 303.10425.
4.2.5. t-Butyl 2-(dimethyl(oxo)-λ6 -sulfanylidene) 2-
phenylacetate (32)
Prepared according to general procedure B using α-ester
sulfoxonium ylide 54 (115.4 mg, 0.6 mmol). Yield: 57% (93.3
mg, 0.35 mmol). Yellow solid. Rf = 0.51 (2% MeOH/AcOEt). 1H
NMR (400 MHz, CDCl3) δ 7.30 (s, 4H), 7.20 (s, 1H), 3.38 (s,
6H), 1.44 (s, 9H). 13C NMR (126 MHz, CDCl3) δ 166.2, 133.7,
133.5, 128.2, 126.6, 78.9, 71.5, 43.7, 29.0. HRMS (FTMS+pESI)
m/z: calculated for C14H20O3S [M+H]+ 269.12059; found
269.12021.
4.2.6. methyl 2-(dimethyl(oxo)-λ6-sulfaneylidene)-
2-(3,5-dimethylphenyl)acetate (33)
Prepared according to general procedure C using α-ester
sulfoxonium ylide 55 (150.2 mg, 1.0 mmol) and 1-bromo-3,5-
dimethylbenzene (277 mg, 204 μL, 1.5 mmol).Yield: 52% (132.4
1
mg, 0.52 mmol). White solid. Rf = 0.41 (AcOEt). H NMR (500
MHz, CDCl3) δ 6.91 (m, 3H), 3.60 (s, 3H), 3.38 (s, 6H), 2.29 (s,
6H). 13C NMR (126 MHz, CDCl3) δ 166.9, 138.0, 132.1, 131.7,
129.4, 70.5, 50.6, 43.1, 21.3. HRMS (ESI+qTOF) m/z: calculated
for C13H18O3S [M+H]+ 255.10494; found 255.1059.
4.2.7. methyl 2-(2-bromophenyl)-2-(dimethyl(oxo)-
λ6-sulfaneylidene)acetate (34)
Prepared according to general procedure A using methyl 2-(2-
bromophenyl)-2-diazoacetate (255.1 mg, 1.0 mmol).37 Yield:
57% (174.0 mg, 0.57 mmol). White solid. Rf = 0.52 (AcOEt). 1H
NMR (400 MHz, CDCl3) δ 7.64 (d, J = 7.9 Hz, 1H), 7.45 (d, J =
7.2 Hz, 1H), 7.31 (t, J = 7.2 Hz, 1H), 7.18 (t, J = 7.0 Hz, 1H),
3.69 (s, 3H), 3.59 (s, 3H), 3.13 (s, 3H). 13C NMR (101 MHz,
CDCl3) δ 166.7, 137.3, 133.2, 133.0, 131.4, 129.9, 127.8, 50.7,
43.4, 41.3. HRMS (ESI+qTOF) m/z: calculated for C11H13BrO3S
[M+H]+ 304.98415; found 304.9852.
4.2.1. methyl 2-(dimethyl(oxo)-λ6-sulfaneylidene)-
2-phenylacetate (1)
Prepared according to general procedure A. Yield: 80% (1.642
1
g, 7.26 mmol). White solid. Rf = 0.31 (AcOEt). H NMR (400
MHz, CDCl3) δ 7.38 – 7.22 (m, 5H), 3.61 (s, 3H), 3.41 (s, 6H).
13C NMR (101 MHz, CDCl3) δ 166.8, 133.8, 132.5, 128.6, 127.3,
70.3, 50.6, 43.3. In good agreement with previously reported
data.15
4.2.2. 2,2,2-trichloroethyl 2-(dimethyl(oxo)-λ6 -
sulfanylidene) 2-phenylacetate (29)
4.2.8. methyl 2-(4-chlorophenyl)-2-(dimethyl(oxo)-
λ6-sulfaneylidene)acetate (35)
Prepared according to general procedure C using α-ester
sulfoxonium ylide 55 (150.2 mg, 1.0 mmol) and 1-bromo-4-
chlorobenzene (287.2 mg, 1.5 mmol). Yield: 93% (121.1 mg,
0.93 mmol). White solid. Rf = 0.39 (AcOEt). 1H NMR (400 MHz,
CDCl3) δ 7.32 – 7.19 (m, 4H), 3.60 (s, 3H), 3.42 (s, 6H). 13C
NMR (126 MHz, CDCl3) δ 166.5, 134.9, 133.1, 130.9, 128.7,
68.7, 50.6, 43.4. HRMS (ESI+qTOF) m/z: calculated for
C11H13ClO3S [M+H]+ 261.03467; found 261.0358.
Prepared according to general procedure A using 2,2,2-
trichloroethyl 2-diazo-2-phenylacetate35 (200.0 mg, 0.68 mmol)
and maintaining the reaction at r.t. for 7 days after the slow
addition (also at r.t.). Yield: 87% (204.2 mg, 0.59 mmol). White
1
solid. Rf = 0.60 (AcOEt). H NMR (400 MHz, CDCl3) δ 7.41 –
7.22 (m, 5H), 4.74 (s, 2H), 3.45 (s, 6H). 13C NMR (101 MHz,
CDCl3) δ 163.7, 133.8, 131.5, 128.5, 127.5, 96.6, 72.9, 71.1,
43.1. In good agreement with previously reported data.36
4.2.3. Phenyl 2-(dimethyl(oxo)-λ6 -sulfanylidene) 2-
phenylacetate (30)
4.2.9. methyl 2-(4-acetylphenyl)-2-(dimethyl(oxo)-
λ6-sulfaneylidene)acetate (36)
Prepared according to general procedure C using α-ester
sulfoxonium ylide 55 (150.2 mg, 1.0 mmol) and 1-(4-
bromophenyl)ethan-1-one (298.6 mg, 1.5 mmol). Yield: 85%
(114.0 mg, 0.425 mmol). Yellow oil. Rf = 0.45 (AcOEt). 1H
NMR (400 MHz, CDCl3) δ 7.88 (m, 2H), 7.42 – 7.37 (m,2H),
3.62 (s, 3H), 3.47 (s, 6H), 2.56 (s, 3H). 13C NMR (126 MHz,
CDCl3) δ 197.8, 166.1, 138.0, 134.8, 132.5, 129.9, 128.8, 128.4,
128.2, 69.5, 50.6, 43.7, 26.6. HRMS (ESI+qTOF) m/z: calculated
for C13H16O4S [M+H]+ 269.08421; found 269.0849.
Prepared according to general procedure B using α-ester
sulfoxonium ylide 52 (170.0 mg, 0.8 mmol). Yield: 63% (146.6
mg, 0.51 mmol). Yellow solid. Rf = 0.62 (AcOEt). 1H NMR (400
MHz, CDCl3) δ 7.44 (m, 2H), 7.39 – 7.26 (m, 5H), 7.15 – 7.10
(m, 1H), 7.09 – 7.04 (m, 2H), 3.43 (s, 6H). 13C NMR (126 MHz,
CDCl3) δ 164.6, 151.6, 133.8, 131.8, 129.1, 128.6, 127.4, 124.8,
122.4, 71.0, 43.2. In good agreement with previously reported
data.13
4.2.4. Benzyl 2-(dimethyl(oxo)-λ6 -sulfanylidene) 2-
phenylacetate (31)
4.3. General procedure for N-H Insertion Reaction
Prepared according to general procedure B using α-ester
sulfoxonium ylide 53 (136.0 mg, 0.6 mmol). Yield: 34% (62.4
mg, 0.21 mmol). Brown oil. Rf = 0.72 (AcOEt). H NMR (500
MHz, CDCl3) δ 7.39 – 7.18 (m, 10H), 5.13 (s, 2H), 3.39 (s, 5H).
13C NMR (101 MHz, CDCl3) δ 165.9, 137.9, 133.8, 132.5, 128.5,
128.4, 127.4, 127.3, 127.2, 70.7, 64.5, 43.3. HRMS
To a 4 mL vial were added sulfoxonium ylide 1 (33.9 mg,
0.15 mmol) and Cu(hfacac)2.xH2O (3.58 mg, 0.0075 mmol, 0.05
eq) at room temperature. The vial was then capped and argon
atmosphere was inserted with aid of an argon filled balloon.
Next, dry toluene (1.5 mL) and aniline (16.5 μL, 0.18 mmol, 1.2
eq) were added (No solvent degassing is needed). The reaction
1

6
Tetrahedron
1
was placed in a preheated heating block (at 60º) and stirred for
0.110 mmol). Brown solid. Rf = 0.33 (10% AcOEt/Hexanes). H
NMR (400 MHz, CDCl3): δ 7.52 – 7.45 (m, 2H), 7.39 – 7.27 (m,
3H), 6.76 – 6.67 (m, 2H), 6.58 – 6.49 (m, 2H), 5.02 (s, 1H), 4.69
(s, 1H), 3.71 (s, 3H), 3.70 (s, 3H). 13C NMR (126 MHz, CDCl3) δ
172.7, 152.6, 140.3, 137.9, 129.0, 128.4, 127.4, 115.0, 114.9,
61.8, 55.8, 52.8. In good agreement with previously reported
data.39
30 min. After this time the reaction was cooled down, the solvent
was evaporated and the crude reaction mixture was direct
inserted into a Biotage IsoleraTM Prime cartridge (Snap Ultra
10g) and purified using AcOEt, Et2O and/or Hexanes eluents (as
described for the TLC elution). Obs: Solid anilines were added
before toluene, alongside with the other solids.
4.3.1. methyl 2-phenyl-2-(phenylamino)acetate (3)
4.3.7. methyl 2-((3-methoxyphenyl)amino)-2-
phenylacetate (9)
Prepared from sulfoxonium ylide 1 (33.9 mg, 0.15 mmol) and
m-anisidine (22.2 mg, 20.2 μL, 0.18 mmol, 1.2 eq). Yield: 84%
Prepared from sulfoxonium ylide 1 (33.9 mg, 0.15 mmol) and
aniline (16.8 mg, 16.4 μL, 0.18 mmol, 1.2 eq). Yield: 91% (32.9
mg, 0.136 mmol). White solid. Rf = 0.47 (10% AcOEt/Hexanes).
1H NMR (500 MHz, CDCl3) δ 7.52 – 7.46 (m, 2H), 7.37-7.27 (m,
3H), 7.11 (m, 2H), 6.72 – 6.67 (m, 1H), 6.55 (m, 2H), 5.08 (s,
1H), 4.95 (s, 1H), 3.72 (s, 3H). 13C NMR (101 MHz, CDCl3) δ
172.4, 146.1, 137.7, 129.4, 129.0, 128.4, 127.4, 118.2, 113.5,
60.9, 52.9. In good agreement with previously reported data.38
(33.55 mg, 0.124 mmol). Yellow oil. Rf
= 0.32 (5%
1
AcOEt/Hexanes). H NMR (500 MHz, CDCl3) δ 7.52 – 7.47 (m,
2H), 7.41 – 7.28 (m, 3H), 7.04 (t, J = 8.1 Hz, 1H), 6.27 (dd, J =
8.1, 2.1 Hz, 1H), 6.19 (dd, J = 8.0, 1.7 Hz, 1H), 6.11 (t, J = 2.1
Hz, 1H), 5.09 (s, 1H), 4.92 (br s, 1H), 3.74 (s, 3H), 3.71 (s, 3H).
13C NMR (101 MHz, CDCl3) δ 172.5, 160.7, 147.3, 137.8, 130.1,
129.0, 128.4, 127.3, 106.6, 103.5, 99.7, 60.8, 55.1, 53.0. In good
agreement with previously reported data 38
4.3.2. methyl 2-phenyl-2-(p-tolylamino)acetate (4)
Prepared from sulfoxonium ylide 1 (33.9 mg, 0.15 mmol) and
p-toluidine (19.3 mg, 0.18 mmol, 1.2 eq). Yield: 79% (30.4 mg,
1
4.3.8. methyl 2-((2-methoxyphenyl)amino)-2-
phenylacetate (10)
0.119 mmol). White solid. Rf = 0.46 (5% AcOEt/Hexanes). H
NMR (400 MHz, CDCl3) δ 7.55 – 7.47 (m, 2H), 7.41 – 7.28 (m,
3H), 6.98 – 6.91 (m, 2H), 6.54 – 6.47 (m, 2H), 5.08 (s, 1H), 4.83
(s, 1H), 3.74 (s, 3H), 2.22 (s, 3H). 13C NMR (101 MHz, CDCl3) δ
172.6, 143.8, 137.8, 129.8, 129.0, 128.4, 127.4, 127.4, 113.6,
61.1, 52.9, 20.5. In good agreement with previously reported
data.38
Prepared from sulfoxonium ylide 1 (33.9 mg, 0.15 mmol) and
o-anisidine (22.2 mg, 20.3 μL, 0.18 mmol, 1.2 eq). Yield: 87%
(35.2 mg, 0.130 mmol). White solid. Rf
= 0.56 (5%
1
AcOEt/Hexanes). H NMR (400 MHz, CDCl3) δ 7.57 – 7.43 (m,
2H), 7.43 – 7.25 (m, 3H), 6.84 – 6.55 (m, 3H), 6.34 (dd, J = 7.7,
1.6 Hz, 1H), 5.47 (d, J = 5.1 Hz, 1H), 5.08 (d, J = 5.6 Hz, 1H),
3.87 (s, 3H), 3.72 (s, 3H). 13C NMR (101 MHz, CDCl3) δ 172.4,
147.1, 137.8, 136.0, 129.0, 128.4, 127.4, 121.1, 117.5, 110.7,
109.7, 60.8, 55.6, 52.8. In good agreement with previously
reported data.38
4.3.3. methyl 2-phenyl-2-(m-tolylamino)acetate (5)
Prepared from sulfoxonium ylide 1 (33.9 mg, 0.15 mmol) and
m-toluidine (19.3 mg, 19.1 μL, 0.18 mmol, 1.2 eq). Yield: 87%
(32.8 mg, 0.129 mmol). White solid. Rf
= 0.44 (5%
1
AcOEt/Hexanes). H NMR (500 MHz, CDCl3) δ 7.52 – 7.45 (m,
2H), 7.38 – 7.26 (m, 3H), 7.00 (t, J = 7.8 Hz, 1H), 6.52 (d, J =
7.5 Hz, 1H), 6.41 (m, 1H), 6.34 (m, 1H), 5.07 (s, 1H), 4.87 (s,
1H), 3.71 (s, 3H), 2.22 (s, 3H). 13C NMR (126 MHz, CDCl3) δ
172.5, 146.1, 139.1, 137.8, 129.2, 129.0, 128.4, 127.4, 119.2,
114.5, 110.5, 60.9, 52.9, 21.7. In good agreement with previously
reported data.38
4.3.9. methyl 2-(benzo[d][1,3]dioxol-5-ylamino)-2-
phenylacetate (11)
Prepared from sulfoxonium ylide 1 (33.9 mg, 0.15 mmol) and
3,4-(methylenedioxy)aniline (24.7 mg, 0.18 mmol, 1.2 eq).
Yield: 69% (29.1 mg, 0.102 mmol). Brown solid. Rf = 0.27 (5%
1
AcOEt/Hexanes). H NMR (400 MHz, CDCl3) δ 7.50 – 7.42 (m,
2H), 7.39 – 7.27 (m, 3H), 6.58 (d, J = 8.3 Hz, 1H), 6.20 (d, J =
2.3 Hz, 1H), 5.98 (dd, J = 8.3, 2.4 Hz, 1H), 5.81 (superimposed,
2H), 4.99 (s, 1H), 4.72 (s, 1H), 3.71 (s, 3H). 13C NMR (126 MHz,
CDCl3) δ 172.5, 148.4, 141.8, 140.2, 137.7, 129.0, 128.5, 127.4,
108.7, 105.3, 100.7, 96.7, 61.7, 52.9. HRMS (FTMS+pESI) m/z:
calculated for C16H15NO4 [M+H]+ 286.10738; found 286.10761.
4.3.4. methyl 2-phenyl-2-(o-tolylamino)acetate (6)
Prepared from sulfoxonium ylide 1 (33.9 mg, 0.15 mmol) and
o-toluidine (19.3 mg, 19.5 μL, 0.18 mmol, 1.2 eq). Yield: 97%
(37.7 mg, 0.146 mmol). White solid. Rf
= 0.51 (5%
1
AcOEt/Hexanes). H NMR (400 MHz, CDCl3) δ 7.48 – 7.39 (m,
2H), 7.32 – 7.19 (m, 3H), 6.99 (d, J = 7.1 Hz, 1H), 6.95 – 6.88
(m, 1H), 6.57 (t, J = 7.4 Hz, 1H), 6.26 (d, J = 7.9 Hz, 1H), 5.04
(s, 1H), 4.82 (s, 1H), 3.66 (s, 3H), 2.20 (s, 3H). 13C NMR (126
MHz, CDCl3) δ 172.6, 144.1, 137.8, 130.4, 129.0, 128.4, 127.3,
127.1, 122.6, 117.9, 110.8, 60.9, 53.0, 17.6. In good agreement
with previously reported data.38
4.3.10. methyl 2-((3,5-dimethoxyphenyl)amino)-2-
phenylacetate (12)
Prepared from sulfoxonium ylide 1 (33.9 mg, 0.15 mmol) and
3,5-dimethoxyaniline (27.6 mg, 0.18 mmol, 1.2 eq). Yield: 67%
(30.0 mg, 0.099 mmol). Brown solid. Rf
= 0.21 (5%
1
AcOEt/Hexanes). H NMR (400 MHz, CDCl3) δ 7.47 (m, 2H),
7.40 – 7.26 (m, 3H), 5.86 (t, J = 2.1 Hz, 1H), 5.74 (d, J = 2.1 Hz,
2H), 5.05 (d, J = 4.5 Hz, 1H), 4.97 (s, 1H), 3.72 (s, 3H), 3.68 (s,
6H). 13C NMR (126 MHz, CDCl3) δ 172.4, 161.7, 147.9, 137.7,
129.0, 128.4, 127.3, 92.5, 90.6, 60.8, 55.2, 53.0. HRMS
(FTMS+pESI) m/z: calculated for C17H19NO4 [M+H]+
302.13868; found 302.14043.
4.3.5. methyl 2-(mesitylamino)-2-phenylacetate (7)
Prepared from sulfoxonium ylide 1 (33.9 mg, 0.15 mmol) and
2,4,6-trimethylaniline (24.3 mg, 25.0 μL, 0.18 mmol, 1.2 eq).
Yield: 89% (39.5 mg, 0.132 mmol). Yellow solid. Rf = 0.51 (5%
1
AcOEt/Hexanes). H NMR (400 MHz, CDCl3): δ 7.41 (m, 2H),
7.37 – 7.26 (m, 3H), 6.76 (s, 2H), 4.87 (s, 1H), 4.27 (s, 1H), 3.68
(s, 3H), 2.21 (s, 6H), 2.19 (s, 3H). 13C NMR (126 MHz, CDCl3) δ
174.1, 141.8, 138.8, 131.3, 129.7, 129.2, 128.8, 128.2, 127.1,
64.2, 52.5, 20.6, 18.9. HRMS (FTMS+pESI) m/z: calculated for
C18H21NO2 [M+H]+ 284.16451; found 284.16573.
4.3.11. methyl 2-((3-aminophenyl)amino)-2-
phenylacetate (13)
Prepared from sulfoxonium ylide 1 (33.9 mg, 0.15 mmol) and
benzene-1,3-diamine (19.5 mg, 0.18 mmol, 1.2 eq). Yield: 52%
(20.1 mg, 0.079 mmol). Brown solid. Rf = 0.25 (25%
4.3.6. methyl 2-((4-methoxyphenyl)amino)-2-
phenylacetate (8)
Prepared from sulfoxonium ylide 1 (33.9 mg, 0.15 mmol) and
p-anisidine (22.2 mg, 0.18 mmol, 1.2 eq). Yield: 73% (29.7 mg,
1
AcOEt/Hexanes). H NMR (500 MHz, CDCl3) δ 7.47 (m, 2H),
7.38 – 7.27 (m, 3H), 6.90 (t, J = 7.9 Hz, 1H), 6.08 – 6.03 (m,
1H), 6.03 – 5.97 (m, 1H), 5.88 (t, J = 2.1 Hz, 1H), 5.05 (s, 1H),

7
4.85 (br s, 1H), 3.72 (s, 3H), 3.53 (br s, 2H). 13C NMR (126
MHz, CDCl3) δ 172.5, 147.5, 147.3, 137.9, 130.2, 129.0, 128.4,
127.3, 105.8, 104.5, 100.3, 60.9, 52.9. HRMS (ESI+qTOF) m/z:
calculated for C15H16N2O2 [M+H]+ 257.12845; found 257.1298.
124.3 (q, J = 272.3 Hz), 116.2, 114.62 (q, J = 3.9 Hz), 110.0 (q,
J = 4.0 Hz), 60.5, 53.1. In good agreement with previously
reported data.41
4.3.17. methyl 2-((3,5-
bis(trifluoromethyl)phenyl)amino)-2-phenylacetate
(19)
4.3.12. methyl 2-((4-nitrophenyl)amino)-2-
phenylacetate (14)
Prepared from sulfoxonium ylide 1 (33.9 mg, 0.15 mmol) and
3,5-bis(trifluoromethyl)aniline (41.2 mg, 28.1 μL, 0.18 mmol, 1.2
eq). Yield: 83% (46.8 mg, 0.124 mmol) . White solid. Rf = 0.39
(5% AcOEt/Hexanes). 1H NMR (500 MHz, CDCl3) δ 7.49 – 7.43
(m, 2H), 7.41 – 7.31 (m, 3H), 7.14 (s, 1H), 6.90 (s, 2H), 5.54 (d,
J = 5.6 Hz, 1H), 5.10 (d, J = 5.7 Hz, 1H), 3.76 (s, 2H). 13C NMR
(126 MHz, CDCl3) δ 171.6, 146.6, 136.2, 132.6 (q, J = 32.8 Hz),
129.4, 129.0, 127.3, 123.5 (q, J = 272.7 Hz), 112.8, 111.20, 60.3,
53.3. In good agreement with previously reported data.42
Prepared from sulfoxonium ylide 1 (33.9 mg, 0.15 mmol) and
p-nitroaniline (24.9 mg, 0.18 mmol, 1.2 eq). Yield: 88% (37.5
mg, 0.131 mmol). Yellow solid. Rf
=
0.36 (15%
1
AcOEt/Hexanes). H NMR (400 MHz, CDCl3) δ 8.05 – 7.97 (m,
2H), 7.45 (m, 2H), 7.42 – 7.31 (m, 3H), 6.56 – 6.45 (m, 2H), 5.85
(d, J = 5.3 Hz, 1H), 5.14 (d, J = 5.6 Hz, 1H), 3.76 (s, 3H).13C
NMR (126 MHz, CDCl3) δ 171.3, 150.9, 139.0, 136.1, 129.3,
129.0, 127.2, 126.3, 112.2, 60.0, 53.4. HRMS (FTMS+pESI)
m/z: calculated for C15H14N2O4 [M+H]+ 287.10263; found
287.10392.
4.3.18. methyl 2-((3-bromophenyl)amino)-2-
phenylacetate (20)
4.3.13. methyl 2-((3-nitrophenyl)amino)-2-
phenylacetate (15)
Prepared from sulfoxonium ylide 1 (33.9 mg, 0.15 mmol) and
3-bromoaniline (31.0 mg, 19.6 μL, 0.18 mmol, 1.2 eq). Yield:
84% (40.1 mg, 0.125 mmol). White solid. Rf = 0.41 (5%
Prepared from sulfoxonium ylide 1 (33.9 mg, 0.15 mmol) and
m-nitroaniline (24.9 mg, 0.18 mmol, 1.2 eq). Yield: 96% (41.3
mg, 1.44 mmol). Yellow solid. Rf = 0.31 (10% AcOEt/Hexanes).
1H NMR (400 MHz, CDCl3) δ 7.54 – 7.45 (m, 3H), 7.41 – 7.29
(m, 4H), 7.22 (t, J = 8.1 Hz, 1H), 6.82 (ddd, J = 8.2, 2.4, 0.6 Hz,
1H), 5.42 (s, 1H), 5.12 (d, J = 5.0 Hz, 1H), 3.76 (s, 3H). 13C
NMR (101 MHz, CDCl3) δ 171.7, 149.3, 146.6, 136.5, 129.9,
129.2, 128.8, 127.3, 119.3, 112.8, 107.4, 60.4, 53.2. HRMS
(ESI+qTOF) m/z: calculated for C15H14N2O4 [M+H]+ 287.10263;
found 287.1040.
1
AcOEt/Hexanes). H NMR (500 MHz, CDCl3) δ 7.47 – 7.43 (m,
2H), 7.39 – 7.28 (m, 3H), 6.94 (t, J = 8.0 Hz, 1H), 6.80 (m, 1H),
6.70 (t, J = 2.0 Hz, 1H), 6.46 – 6.41 (m, 1H), 5.05 (m, 2H), 3.73
(s, 3H). 13C NMR (126 MHz, CDCl3) δ 172.0, 147.2, 137.1,
130.6, 129.1, 128.6, 127.3, 123.3, 121.0, 116.3, 112.1, 60.5, 53.1.
In good agreement with previously reported data.38
4.3.19. methyl 2-((4-chlorophenyl)amino)-2-
phenylacetate (21)
4.3.14. methyl 2-((2-nitrophenyl)amino)-2-
phenylacetate (16)
Prepared from sulfoxonium ylide 1 (33.9 mg, 0.15 mmol) and
o-nitroaniline (24.9 mg, 0.18 mmol, 1.2 eq). Yield: 18% (7.8 mg,
Prepared from sulfoxonium ylide 1 (33.9 mg, 0.15 mmol) and
4-chloroaniline (23.0 mg, 0.18 mmol, 1.2 eq). Yield: 84% (34.6
mg, 0.126 mmol). White solid. Rf = 0.41 (5% AcOEt/Hexanes).
1H NMR (400 MHz, CDCl3) δ 7.49 – 7.43 (m, 2H), 7.39 – 7.28
(m, 3H), 7.10 – 7.03 (m, 2H), 6.51 – 6.44 (m, 2H), 5.04
(superimposed, 2H), 3.74 (s, 3H). 13C NMR (101 MHz, CDCl3) δ
172.1, 144.5, 137.2, 129.2, 129.1, 128.6, 127.3, 122.8, 114.6,
60.8, 53.0. In good agreement with previously reported data.38
1
0.027 mmol). Yellow solid. Rf = 0.29 (10% Et2O/Hexanes). H
NMR (500 MHz, CDCl3) δ 9.10 (d, J = 5.4 Hz, 1H), 8.21 (dd, J =
8.6, 1.6 Hz, 1H), 7.53 – 7.46 (m, 2H), 7.42 – 7.28 (m, 4H), 6.68
(ddd, J = 8.4, 7.0, 1.2 Hz, 1H), 6.56 (dd, J = 8.6, 1.0 Hz, 1H),
5.24 (d, J = 5.8 Hz, 1H), 3.78 (s, 3H). 13C NMR (126 MHz,
CDCl3) δ 170.8, 143.1, 136.3, 136.2, 133.2, 129.4, 129.0, 127.2,
127.1, 116.5, 114.6, 60.4, 53.4. In good agreement with
previously reported data.40
4.3.20. methyl 2-((4-bromophenyl)amino)-2-
phenylacetate (22)
Prepared from sulfoxonium ylide 1 (33.9 mg, 0.15 mmol) and
4-bromoaniline (31.0 mg, 0.18 mmol, 1.2 eq). Yield: 86% (41.4
mg, 0.129 mmol). White solid. Rf = 0.41 (5% AcOEt/Hexanes).
1H NMR (400 MHz, CDCl3) δ 7.51 – 7.42 (m, 2H), 7.41 – 7.28
(m, 3H), 7.25 – 7.15 (m, 2H), 6.48 – 6.38 (m, 2H), 5.03 (s, 2H),
3.74 (s, 3H). 13C NMR (101 MHz, CDCl3) δ 172.1, 144.9, 137.2,
132.1, 129.1, 128.6, 127.3, 115.1, 109.9, 60.7, 53.0. In good
agreement with previously reported data.38
4.3.15. methyl 2-phenyl-2-((2-
(trifluoromethyl)phenyl)amino)acetate (17)
Prepared from sulfoxonium ylide 1 (33.9 mg, 0.15 mmol) and
2-(trifluoromethyl)aniline (29.0 mg, 22.6 μL, 0.18 mmol, 1.2 eq).
Yield: 68% (31.7 mg, 0.103 mmol). Yellow solid. Rf = 0.51 (5%
1
AcOEt/Hexanes). H NMR (500 MHz, CDCl3) δ 7.51 – 7.42 (m,
3H), 7.39 – 7.27 (m, 3H), 7.19 (t, J = 7.8 Hz, 1H), 6.70 (t, J = 7.6
Hz, 1H), 6.41 (d, J = 8.3 Hz, 1H), 5.84 (br d, 1H), 5.13 (d, J = 5.5
Hz, 1H), 3.74 (s, 3H). 13C NMR (126 MHz, CDCl3) δ 171.6,
143.3, 137.0, 133.1, 129.1, 128.6, 127.2, 126.8 (q, J = 5.5 Hz),
125.2 (q, J = 272.3 Hz), 116.9, 114.4 (q, J = 29.6 Hz), 112.8,
60.2, 53.2. HRMS (FTMS+pESI) m/z: calculated for
C16H14F3NO2 [M+H]+ 310.10494; found 310.10618.
4.3.21. methyl 2-((3-fluorophenyl)amino)-2-
phenylacetate (23)
Prepared from sulfoxonium ylide 1 (33.9 mg, 0.15 mmol) and
3-fluoroaniline (20.0 mg, 17.3 μL, 0.18 mmol, 1.2 eq). Yield:
83% (31.6 mg, 0.124 mmol). White solid. Rf = 0.36 (5%
1
AcOEt/Hexanes). H NMR (500 MHz, CDCl3) δ 7.49 – 7.44 (m,
2H), 7.41 – 7.28 (m, 3H), 7.07 – 7.01 (m, 1H), 6.40 – 6.35 (m,
1H), 6.33 (ddd, J = 8.2, 2.2, 0.7 Hz, 1H), 6.21 (dt, J = 11.4, 2.3
Hz, 1H), 5.11 (s, 1H), 5.03 (s, 1H), 3.73 (s, 3H). 13C NMR (101
MHz, CDCl3) δ 172.1, 164.0 (d, J = 243.1 Hz), 147.7 (d, J = 10.8
Hz), 137.2, 130.4 (d, J = 10.2 Hz), 129.1, 128.6, 127.3, 109.4 (d,
J = 2.2 Hz), 104.7 (d, J = 21.5 Hz), 100.3 (d, J = 25.6 Hz), 60.7,
53.1. HRMS (FTMS+pESI) m/z: calculated for C15H14FNO2
[M+H]+ 260.10813; found 260.10967.
4.3.16. methyl 2-phenyl-2-((3-
(trifluoromethyl)phenyl)amino)acetate (18)
Prepared from sulfoxonium ylide 1 (33.9 mg, 0.15 mmol) and
3-(trifluoromethyl)aniline (29.0 mg, 22.5 μL, 0.18 mmol, 1.2 eq).
Yield: 86% (39.3 mg, 0.127 mmol). White solid. Rf = 0.33 (5%
1
AcOEt/Hexanes). H NMR (500 MHz, CDCl3) δ 7.53 – 7.46 (m,
2H), 7.44 – 7.30 (m, 3H), 7.20 (t, J = 7.9 Hz, 1H), 6.97 – 6.91
(m, 1H), 6.80 (s, 1H), 6.67 (dd, J = 8.1, 2.3 Hz, 1H), 5.22 (s, 1H),
5.10 (s, 1H), 3.75 (s, 3H). 13C NMR (101 MHz, CDCl3) δ 172.0,
146.1, 137.0, 131.6 (q, J = 31.9 Hz), 129.81, 129.2, 128.7, 127.3,
4.3.22. methyl 2-((3-chlorophenyl)amino)-2-
phenylacetate (24)

8
Tetrahedron
Prepared from sulfoxonium ylide 1 (33.9 mg, 0.15 mmol)
Hz, 1H), 6.64 – 6.57 (m, 2H), 5.24 (s, 1H), 4.88 (s, 1H), 4.76 (d,
J = 1.4 Hz, 2H). 13C NMR (101 MHz, CDCl3) δ 170.7, 145.8,
136.7, 129.4, 129.1, 128.8, 127.5, 118.6, 113.6, 94.4, 74.6, 60.9.
HRMS (FTMS+pESI) m/z: calculated for C16H14Cl3NO2 [M+H]+
358.01629; found 358.01851.
and 3-chloroaniline (23.0 mg, 18.7 μL, 0.18 mmol, 1.2 eq).
Yield: 81% (33.8 mg, 0.122 mmol). White solid. Rf = 0.44 (5%
AcOEt/Hexanes). H NMR (400 MHz, CDCl3) δ 7.50 – 7.42 (m,
2H), 7.40 – 7.28 (m, 3H), 7.00 (t, J = 8.1 Hz, 1H), 6.65 (ddd, J =
7.9, 1.9, 0.8 Hz, 1H), 6.53 (t, J = 2.1 Hz, 1H), 6.41 (ddd, J = 8.2,
2.3, 0.7 Hz, 1H), 5.06 (m, 2H), 3.72 (s, 3H). 13C NMR (101
MHz, CDCl3) δ 172.0, 147.1, 137.1, 135.0, 130.3, 129.1, 128.6,
127.3, 118.1, 113.4, 111.8, 60.6, 53.1. In good agreement with
previously reported data.38
1
4.3.28. phenyl 2-phenyl-2-(phenylamino)acetate
(39)
Prepared from sulfoxonium ylide 30 (43.2 mg, 0.15 mmol, 1.0
eq) and aniline (16.8 mg, 16.4 μL, 0.18 mmol, 1.2 eq). Yield:
57% (25.9 mg, 0.085 mmol). Pale Yellow solid. Rf = 0.42 (5%
AcOEt/Hexanes). 1H NMR (400 MHz, CDCl3) δ 7.64 – 7.58 (m,
2H), 7.45 – 7.28 (m, 5H), 7.26 – 7.11 (m, 3H), 6.98 – 6.91 (m,
2H), 6.74 (m, 1H), 6.64 (m, 2H), 5.34 (d, J = 5.6 Hz, 1H), 4.95
(d, J = 5.2 Hz, 1H). 13C NMR (126 MHz, CDCl3) δ 170.8, 150.6,
146.0, 137.2, 129.6, 129.5, 129.2, 128.7, 127.5, 126.3, 121.3,
118.6, 113.6, 61.2. HRMS (FTMS+pESI) m/z: calculated for
C20H17NO2 [M+H]+ 304.13321; found 304.13532.
4.3.23. methyl 2-((3-chloro-4-
methoxyphenyl)amino)-2-phenylacetate (25)
Prepared from sulfoxonium ylide 1 (33.9 mg, 0.15 mmol) and
3-chloro-4-methoxyaniline (28.4 mg, 0.18 mmol, 1.2 eq). Yield:
77% (35.4 mg, 0.116 mmol). Yellowish solid. Rf = 0.35 (10%
1
AcOEt/Hexanes). H NMR (500 MHz, CDCl3) δ 7.51 – 7.42 (m,
2H), 7.40 – 7.27 (m, 3H), 6.73 (d, J = 8.8 Hz, 1H), 6.63 (d, J =
2.6 Hz, 1H), 6.40 (dd, J = 8.8, 2.5 Hz, 1H), 5.01 (s, 1H), 4.65 (br
s, 1H), 3.77 (s, 3H), 3.72 (s, 3H). 13C NMR (126 MHz, CDCl3) δ
172.5, 148.0, 140.6, 137.5, 129.1, 128.6, 127.3, 123.4, 116.0,
114.1, 112.7, 61.2, 57.0, 53.0. HRMS (ESI+qTOF) m/z:
calculated for C16H16ClNO3 [M+H]+ 306.08915; found 306.0912.
4.3.29. benzyl 2-phenyl-2-(phenylamino)acetate
(40)
Prepared from sulfoxonium ylide 31 (45.3 mg, 0.15 mmol, 1.0
eq) and aniline (16.8 mg, 16.4 μL, 0.18 mmol, 1.2 eq). Yield:
53% (25.2 mg, 0.080 mmol). White solid. Rf = 0.42 (5%
1
4.3.24. methyl 2-((3-chloro-2-methylphenyl)amino)-
2-phenylacetate (26)
AcOEt/Hexanes). H NMR (500 MHz, CDCl3) δ 7.52 – 7.45 (m,
2H), 7.36 – 7.27 (m, 6H), 7.21 – 7.15 (m, 2H), 7.14 – 7.08 (m,
2H), 6.69 (tt, J = 7.4, 1.0 Hz, 1H), 6.61 – 6.53 (m, 2H), 5.23 –
5.08 (m, 3H), 4.95 (s, 1H). 13C NMR (126 MHz, CDCl3) δ 171.8,
146.0, 137.6, 135.4, 129.34, 129.0, 128.7, 128.5, 128.4, 128.0,
127.4, 118.3, 113.6, 67.5, 61.0. In good agreement with
previously reported data.39
Prepared from sulfoxonium ylide 1 (33.9 mg, 0.15 mmol) and
3-chloro-2-methylaniline (25.5 mg, 21.5 μL, 0.18 mmol, 1.2 eq).
Yield: 81% (35.3 mg, 0.122 mmol). Yellowish solid. Rf = 0.42
1
(10% AcOEt/Hexanes). H NMR (400 MHz, CDCl3) δ 7.51 –
7.43 (m, 2H), 7.40 – 7.27 (m, 3H), 6.85 (t, J = 8.1 Hz, 1H), 6.74
(d, J = 7.5 Hz, 1H), 6.21 (d, J = 8.0 Hz, 1H), 5.06 (m, 2H), 3.74
(s, 3H), 2.35 (s, 3H). 13C NMR (101 MHz, CDCl3) δ 172.31,
145.2, 137.3, 134.8, 129.1, 128.6, 127.3, 127.2, 120.3, 118.8,
109.2, 60.9, 53.2, 13.8. HRMS (ESI+qTOF) m/z: calculated for
C16H16ClNO2 [M+H]+ 290.09423; found 290.0957.
4.3.30. tert-butyl 2-phenyl-2-(phenylamino)acetate
(41)
Prepared from sulfoxonium ylide 32 (40.22 mg, 0.15 mmol,
1.0 eq) and aniline (16.8 mg, 16.4 μL, 0.18 mmol, 1.2 eq). Yield:
72% (30.6 mg, 0.108 mmol). Yellow solid. Rf = 0.66 (10%
1
4.3.25. methyl 2-(naphthalen-1-ylamino)-2-
phenylacetate (27)
AcOEt/Hexanes). H NMR (500 MHz, CDCl3) δ 7.47 (m, 2H),
7.35 – 7.30 (m, 2H), 7.30 – 7.25 (m, 1H), 7.13 – 7.08 (m, 2H),
6.70 – 6.65 (m, 1H), 6.54 (m, 2H), 4.95 (s, 2H), 1.38 (s, 9H). 13C
NMR (126 MHz, CDCl3) δ 171.0, 146.3, 138.3, 129.3, 128.8,
Prepared from sulfoxonium ylide 1 (33.9 mg, 0.15 mmol) and
1-naphtylamine (25.8 mg, 0.18 mmol, 1.2 eq). Yield: 71% (31.0
mg, 0.106 mmol). Brown solid. Rf = 0.42 (5% AcOEt/Hexanes).
1H NMR (400 MHz, CDCl3) δ 8.04 – 7.98 (m, 1H), 7.82 – 7.73
(m, 1H), 7.59 – 7.53 (m, 2H), 7.52 – 7.43 (m, 2H), 7.39 – 7.27
(m, 3H), 7.19 (m, 2H), 6.33 (dd, J = 7.1, 1.4 Hz, 1H), 5.78 (s,
1H), 5.24 (s, 1H), 3.76 (s, 3H). 13C NMR (101 MHz, CDCl3) δ
172.5, 141.1, 137.5, 134.4, 129.0, 128.8, 128.5, 127.4, 126.4,
126.0, 125.1, 123.6, 120.2, 118.2, 105.7, 60.9, 53.1. In good
agreement with previously reported data.39
128.1, 127.2, 117.9, 113.5, 82.5, 61.4, 28.0.
HRMS
(FTMS+pESI) m/z: calculated for C18H21NNaO2 [M+Na]+
306.14700; found 306.14768.
4.3.31. methyl 2-(3,5-dimethylphenyl)-2-
(phenylamino)acetate (42)
Prepared from sulfoxonium ylide 33 (38.2 mg, 0.15 mmol, 1.0
eq) and aniline (16.8 mg, 16.4 μL, 0.18 mmol, 1.2 eq). Yield:
86% (34.8 mg, 0.129 mmol). Colorless oil. Rf = 0.44 (5%
AcOEt/Hexanes). 1H NMR (400 MHz, CDCl3) δ 7.17 – 7.05 (m,
3H), 6.93 (s, 1H), 6.74 – 6.64 (m, 1H), 6.56 (m, 1H), 4.98 (s,
1H), 4.87 (s, 1H), 3.72 (s, 3H), 2.30 (s, 6H). 13C NMR (101 MHz,
CDCl3) δ 172.7, 146.3, 138.6, 137.6, 130.2, 129.3, 125.1, 118.2,
113.5, 60.9, 52.9, 21.4. HRMS (ESI+qTOF) m/z: calculated for
C17H19NO2 [M+H]+ 270.14886; found 270.1504.
4.3.26. methyl 2-(methyl(phenyl)amino)-2-
phenylacetate (28)
Prepared from sulfoxonium ylide 1 (33.9 mg, 0.15 mmol) and
N-methylaniline (19.3 mg, 19.5 μL, 0.18 mmol, 1.2 eq). Yield:
87% (33.3 mg, 0.130 mmol). Colorless oil. Rf = 0.45 (5%
AcOEt/Hexanes). 1H NMR (400 MHz, CDCl3) δ 7.43 – 7.20 (m,
7H), 6.87 (m, 2H), 6.80 (t, J = 7.3 Hz, 1H), 5.67 (s, 1H), 3.77 (s,
3H), 2.79 (s, 3H). 13C NMR (126 MHz, CDCl3) δ 172.5, 145.0,
135.9, 129.4, 128.8, 128.5, 128.2, 118.2, 113.6, 65.8, 52.1, 34.6.
In good agreement with previously reported data.15
4.3.32. methyl 2-((4-bromophenyl)amino)-2-(3,5-
dimethylphenyl)acetate (43)
Prepared from sulfoxonium ylide 33 (38.2 mg, 0.15 mmol, 1.0
eq) and 4-bromoaniline (31.0 mg, 0.18 mmol, 1.2 eq). Yield:
81% (42.2 mg, 0.121 mmol). White solid. Rf = 0.45 (5%
4.3.27. 2,2,2-trichloroethyl 2-phenyl-2-
(phenylamino)acetate (38)
1
AcOEt/Hexanes). H NMR (400 MHz, CDCl3) δ 7.21 – 7.14 (m,
Prepared from sulfoxonium ylide 29 (51.5 mg, 0.15 mmol, 1.0
eq) and aniline (16.8 mg, 16.4 μL, 0.18 mmol, 1.2 eq). Yield:
84% (45.2 mg, 0.126 mmol). White solid. Rf = 0.48 (5%
AcOEt/Hexanes). H NMR (400 MHz, CDCl3) δ 7.54 (m, 2H),
7.40 – 7.29 (m, 3H), 7.18 – 7.10 (m, 2H), 6.73 (tt, J = 7.5, 1.0
2H), 7.05 (s, 2H), 6.94 (s, 1H), 6.48 – 6.37 (m, 2H), 4.92 (s, 2H),
3.72 (s, 3H), 2.29 (s, 6H). 13C NMR (101 MHz, CDCl3) δ 172.4,
145.2, 138.7, 137.0, 132.0, 130.4, 125.0, 115.0, 109.8, 60.7, 53.0,
21.4. HRMS (ESI+qTOF) m/z: calculated for C17H18BrNO2
[M+H]+ 348.05937; found 348.0615.
1

9
1
4.3.33. methyl 2-(2-bromophenyl)-2-
AcOEt/Hexanes). H NMR (400 MHz, CDCl3) δ 7.99 – 7.90
(phenylamino)acetate (44)
(m, 2H), 7.57 (m, 2H), 7.21 – 7.14 (m, 2H), 6.44 – 6.32 (m, 2H),
5.08 (s, 2H), 3.74 (s, 3H), 2.58 (s, 3H). 13C NMR (101 MHz,
CDCl3) δ 197.6, 171.3, 144.5, 142.5, 137.3, 132.2, 129.1, 127.6,
115.1, 110.3, 60.5, 53.3, 26.8. HRMS (ESI+qTOF) m/z:
calculated for C17H16BrNO3 [M+H]+ 362.03863; found 362.0403.
Prepared from sulfoxonium ylide 34 (45.8 mg, 0.15 mmol, 1.0
eq) and aniline (16.8 mg, 16.4 μL, 0.18 mmol, 1.2 eq). Yield:
85% (40.6 mg, 0.127 mmol). White solid. Rf = 0.37 (5%
1
AcOEt/Hexanes). H NMR (400 MHz, CDCl3) δ 7.60 (dd, J =
8.0, 1.2 Hz, 1H), 7.45 (dd, J = 7.8, 1.7 Hz, 1H), 7.31 – 7.21 (m,
1H), 7.19 – 7.07 (m, 3H), 6.69 (t, J = 7.3 Hz, 1H), 6.56 (m, 2H),
5.59 (s, 1H), 5.09 (br s, 1H), 3.72 (s, 3H). 13C NMR (101 MHz,
CDCl3) δ 171.9, 145.7, 137.4, 133.4, 129.8, 129.4, 128.5, 128.2,
124.6, 118.4, 113.6, 59.6, 53.1. HRMS (ESI+qTOF) m/z:
calculated for C15H14BrNO2 [M+H]+ 320.02807; found 320.0301.
4.3.39. Methyl 2-(phenylamino)propanoate (50)
Prepared from sulfoxonium ylide 37 (28.8 mg, 0.15 mmol, 1.0
eq) and aniline (16.8 mg, 16.4 μL, 0.18 mmol, 1.2 eq). This
reaction was performed under microwave irradiation at 150ºC,
for 30 min. Yield: 18% (4.82 mg, 0.027 mmol). Colorless oil. Rf
1
= 0.41 (10% AcOEt/Hexanes). H NMR (400 MHz, CDCl3) δ
4.3.34. methyl 2-(2-bromophenyl)-2-((4-
bromophenyl)amino)acetate (45)
7.22 – 7.11 (m, 2H), 6.74 (t, J = 7.3 Hz, 1H), 6.64 – 6.57 (m,
2H), 4.15 (q, J = 6.9 Hz, 1H), 3.73 (s, 3H), 1.48 (d, J = 6.9 Hz,
3H). 13C NMR (101 MHz, CDCl3) δ 175.3, 146.7, 129.5, 118.5,
113.5, 52.4, 52.1, 19.1. In good agreement with previously
reported data.43
Prepared from sulfoxonium ylide 34 (45.8 mg, 0.15 mmol, 1.0
eq) and 4-bromoaniline (31.0 mg, 0.18 mmol, 1.2 eq). Yield:
78% (46.7 mg, 0.117 mmol). White solid. Rf = 0.33 (5%
1
AcOEt/Hexanes). H NMR (400 MHz, CDCl3) δ 7.60 (dd, J =
4.3.40. Methyl 2-((4-
bromophenyl)amino)propanoate (51)
8.0, 1.2 Hz, 1H), 7.40 (dd, J = 7.8, 1.7 Hz, 1H), 7.29 – 7.23 (m,
1H), 7.23 – 7.12 (m, 3H), 6.47 – 6.39 (m, 2H), 5.54 (s, 1H), 5.14
(br s, 1H), 3.73 (s, 3H). 13C NMR (101 MHz, CDCl3) δ 171.6,
144.6, 136.9, 133.5, 132.1, 130.0, 128.4, 128.3, 124.6, 115.2,
110.2, 59.5, 53.2. HRMS (ESI+qTOF) m/z: calculated for
C15H13Br2NO2 [M+H]+ 397.93858; found 397.9403.
Prepared from sulfoxonium ylide 37 (28.8 mg, 0.15 mmol, 1.0
eq) and 4-bromoaniline (31.0 mg, 0.18 mmol, 1.2 eq). This
reaction was performed under microwave irradiation at 150ºC,
for 30 min. Yield: 32% (12.3 mg, 0.048 mmol). Colorless oil. Rf
1
= 0.45 (15% AcOEt/Hexanes). H NMR (400 MHz, CDCl3) δ
4.3.35. methyl 2-(4-chlorophenyl)-2-
(phenylamino)acetate (46)
7.25 (m, 2H), 6.48 (m, 2H), 4.17 (br s, 1H), 4.10 (q, J = 7.0 Hz,
1H), 3.73 (s, 3H), 1.47 (d, J = 6.8 Hz, 3H). 13C NMR (126 MHz,
CDCl3) δ 174.9, 145.7, 132.2, 115.1, 110.2, 52.5, 52.0, 18.9. In
good agreement with previously reported data.43
Prepared from sulfoxonium ylide 35 (39.1 mg, 0.15 mmol, 1.0
eq) and aniline (16.8 mg, 16.4 μL, 0.18 mmol, 1.2 eq). Yield:
80% (33.3 mg, 0.121 mmol). Colorless oil. Rf = 0.55 (10%
AcOEt/Hexanes). 1H NMR (400 MHz, CDCl3) δ 7.49 – 7.42 (m,
2H), 7.37 – 7.29 (m, 2H), 7.18 – 7.09 (m, 1H), 6.75 – 6.70 (m,
Acknowledgements
We would like to thank São Paulo Research Foundation
(FAPESP) for fellowship grant (2018/17800-3) to L.G.F., and for
financial support (2017/23329-9 and 2013/18009-4). We also
thank National Council for Scientific and Technological
Development (CNPq) for fellowship grant 140276/2018-1 and
Dr. Radell E. Pérez for kindly supply compounds 36 and 37.
1H), 6.54 (m, 2H), 5.06 (s, 1H), 5.00 (br s, 1H), 3.75 (s, 3H). 13
C
NMR (126 MHz, CDCl3) δ 171.9, 145.7, 136.3, 134.3, 129.4,
129.2, 128.7, 118.4, 113.6, 60.2, 53.1. HRMS (ESI+qTOF) m/z:
calculated for C15H14ClNO2 [M+H]+ 276.07858; found 276.0803.
4.3.36. methyl 2-((4-bromophenyl)amino)-2-(4-
chlorophenyl)acetate (47)
Appendix A. Supplementary data
Prepared from sulfoxonium ylide 35 (39.1 mg, 0.15 mmol, 1.0
eq) and 4-bromoaniline (31.0 mg, 0.18 mmol, 1.2 eq). Yield:
70% (37.4 mg, 0.105 mmol). White solid. Rf = 0.34 (5%
Supplementary data (NMR spectra) related to this article can
be found at …
1
AcOEt/Hexanes). H NMR (400 MHz, CDCl3) δ 7.43 – 7.36 (m,
References
2H), 7.36 – 7.28 (m, 2H), 7.23 – 7.15 (m, 2H), 6.45 – 6.33 (m,
2H), 5.04 (br s, 1H), 4.99 (s, 1H), 3.73 (s, 3H). 13C NMR (101
MHz, CDCl3) δ 171.6, 144.6, 135.8, 134.5, 132.1, 129.3, 128.6,
115.1, 110.2, 60.1, 53.2. HRMS (ESI+qTOF) m/z: calculated for
C15H13BrClNO2 [M+H]+ 353.98910; found 353.9907.
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4.3.37. methyl 2-(4-acetylphenyl)-2-
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Prepared from sulfoxonium ylide 36 (40.2 mg, 0.15 mmol, 1.0
eq) and aniline (16.8 mg, 16.4 μL, 0.18 mmol, 1.2 eq). Yield:
24% (10.4 mg, 0.037 mmol). Yellow oil. Rf = 0.16 (10%
1
AcOEt/Hexanes). H NMR (400 MHz, CDCl3) δ 7.95 (d, J = 8.1
Hz, 2H), 7.62 (d, J = 8.0 Hz, 1H), 7.12 (t, J = 7.8 Hz, 2H), 6.70
(t, J = 7.3 Hz, 1H), 6.51 (d, J = 8.0 Hz, 2H), 5.17 (s, 1H), 3.75 (s,
3H), 2.59 (s, 3H). 13C NMR (126 MHz, CDCl3) δ 197.70 (s),
171.9, 145.4, 143.4, 137.2, 129.4, 129.1, 127.7, 118.6, 113.7,
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Prepared from sulfoxonium ylide 36 (40.2 mg, 0.15 mmol, 1.0
eq) and 4-bromoaniline (31.0 mg, 0.18 mmol, 1.2 eq). Yield:
39% (21.2 mg, 0.059 mmol). Yellow solid. Rf = 0.13 (10%

10
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Declaration of interests
☒ The authors declare that they have no known competing financial interests or personal relationships
that could have appeared to influence the work reported in this paper.
☐The authors declare the following financial interests/personal relationships which may be considered
as potential competing interests: