Synthesis of Triarylmethanes via Palladium-Catalyzed Suzuki Coupling of Trimethylammonium Salts and Arylboronic Acids

Article abstract of DOI:10.1021/acs.joc.8b00965

An efficient palladium-catalyzed Suzuki coupling of 1,1-diarylmethyl-trimethylammonium triflates with arylboronic acids is reported. This reaction offers a novel approach to triarylmethane derivatives in good to excellent yields with the palladium-catalyzed C-N bond cleavage as the key feature. Broad substrate scope regarding both reaction partners are observed. Moreover, reactive functional groups such as vinyl and formyl groups are conserved in this transformation.

Full text of DOI:10.1021/acs.joc.8b00965

Subscriber access provided by TUFTS UNIV
Note
Synthesis of Triarylmethanes via Palladium-Catalyzed Suzuki
Coupling of Trimethylammonium Salts and Arylboronic acids
Zhenming Zhang, Hui Wang, Nianli Qiu, Yujing Kong, Wenjuan Zeng, Yongquan Zhang, and Junfeng Zhao
J. Org. Chem., Just Accepted Manuscript • DOI: 10.1021/acs.joc.8b00965 • Publication Date (Web): 06 Jul 2018
Downloaded from http://pubs.acs.org on July 6, 2018
Just Accepted
“Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted
online prior to technical editing, formatting for publication and author proofing. The American Chemical
Society provides “Just Accepted” as a service to the research community to expedite the dissemination
of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in
full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully
peer reviewed, but should not be considered the official version of record. They are citable by the
Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore,
the “Just Accepted” Web site may not include all articles that will be published in the journal. After
a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web
site and published as an ASAP article. Note that technical editing may introduce minor changes
to the manuscript text and/or graphics which could affect content, and all legal disclaimers and
ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or
consequences arising from the use of information contained in these “Just Accepted” manuscripts.
is published by the American Chemical Society. 1155 Sixteenth Street N.W.,
Washington, DC 20036
Published by American Chemical Society. Copyright © American Chemical Society.
However, no copyright claim is made to original U.S. Government works, or works
produced by employees of any Commonwealth realm Crown government in the course
of their duties.

Page 1 of 6
The Journal of Organic Chemistry
Synthesis of Triarylmethanes via Palladium-Catalyzed Suzuki
Coupling of Trimethylammonium Salts and Arylboronic acids
1
2
3
4
5
6
Zhenming Zhang, Hui Wang, Nianli Qiu, Yujing Kong, Wenjuan Zeng, Yongquan Zhang, Junfeng
Zhao*
7
8
9
Key Laboratory of Chemical Biology of Jiangxi Province, College of Chemistry and Chemical Engineering, Jiangxi Normal
University, Nanchang, 330022, P. R. China
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Supporting Information
ABSTRACT: An efficient palladiumꢀcatalyzed Suzuki coupling of
N,N,Nꢀtrimethylꢀ1,1ꢀdiarylmethanaminium triflates with arylboronic acids
is reported. This reaction offers a novel approach to triarylmethane derivaꢀ
tives in good to excellent yields with the palladiumꢀcatalyzed C─N bond
cleavage as the key feature. Broad substrate scopes regarding to both reacꢀ
tion partners are observed. Moreover, reactive functional groups such as
vinyl and formyl groups are conserved in this transformation.
The triarylmethane moiety is a valuable structural motif
widely found in numerous naturally occurring compounds,1
pharmaceuticals,2 functional materials,3 dyes,4 and biologically
active molecules.5 Owing to the fascinating profiles of triarylꢀ
methanes, considerable efforts in the development of efficient
methods for their construction have been made in past decꢀ
ades.6 Among them, palladiumꢀcatalyzed crossꢀcoupling has
been proven to be a powerful protocol.7 The coupling partners
including diarylmethanes,8 diarylacetonitriles,9 and Nꢀ
tosylhydrazones10 have been used to couple with aryl halides
to deliver the triarylmethane products. In addition, palladiumꢀ
catalyzed Suzuki coupling reaction of organoborane reagents
for the synthesis of triarylmethane using diarylmethyl carꢀ
bonates or diarylmethyl phenyl sulfones as electrophile has
also been reported.11 However, these methods are usually limꢀ
ited in substrate scope and require harsh reaction conditions.
Thus, novel and efficient coupling reagents for the synthesis of
triarylmethanes through palladiumꢀcatalyzed crossꢀcoupling
are highly desirable.
Table 1. Optimization of Reaction Conditionsa
NMe3 OTf
B(OH)2
Pd cat., ligand
+
solvent, Na2CO3, N2
100 o
C
1a
2a
3a
yield
(%)b
45
entry
cat.
ligand solvent time
1
2
3
PdCl2
PdCl2
PdCl2
PPh3
PPh3
PPh3
PPh3
EtOH
DMF
MeCN 24 h
DMSO 24 h
24 h
24 h
10
29
21
58
82
83
24
67
75
74
92
79
4
PdCl2
5
PdCl2
PPh3 dioxane 24 h
6
7
8
9
PdCl2
PdCl2
PdCl2
PPh3
PPh3
PPh3
PPh3
PPh3
PPh3
PPh3
DCE
DCE
DCE
DCE
DCE
DCE
DCE
DCE
DCE
DCE
DCE
DCE
DCE
DCE
DCE
DCE
DCE
24 h
12 h
6 h
Pd(OAc)2
Pd2(dba)3
[PdCl2(cod)]
[PdCl2(PhCN)2]
12 h
12 h
12 h
12 h
12 h
12 h
12 h
12 h
12 h
12 h
12 h
12 h
Since Wenkert’s pioneering work,12 the use of trimeꢀ
thylammonium salts as coupling partners in transitionꢀmetalꢀ
catalyzed crossꢀcoupling reactions through C─N bond cleavꢀ
age has received considerable attention.13 However, the pallaꢀ
dium catalyzed crossꢀcoupling reaction of trimethylammoniꢀ
um salts kept as a formidable challenge for a long time.14 Very
recently, Phipps group and our group independently developed
the palladiumꢀcatalyzed Suzuki crossꢀcoupling of benzyltrimeꢀ
thylammonium salts with arylboronic acids to afford diarylmeꢀ
thane derivatives.15 Encouraged by this work, we envisioned
that the synthesis of more challenging triarylmethane derivaꢀ
tives could also be achieved via palladiumꢀcatalyzed Suzuki
crossꢀcoupling of trimethylammonium salts and arylboronic
acids. Herein, we report palladiumꢀcatalyzed Suzuki coupling
between N,N,Nꢀtrimethylꢀ1,1ꢀdiarylmethan ammonium triꢀ
flates and arylboronic acids for the construction of various
triarylmethanes.
10
11
12
13
14
15
16
17
18
19
20
21c
22d
[Pd(cinnamyl)Cl]2 PPh3
FeCl2
CuCl
NiBr2
PPh3
PPh3
PPh3
ꢀꢀ
trace
Trace
trace
Trace
Trace
90
[PdCl2(PhCN)2]
[PdCl2(PhCN)2]
[PdCl2(PhCN)2] Binap
[PdCl2(PhCN)2] PCy3
[PdCl2(PhCN)2] PCy3
Bpy
94
12 h 94(90)
12 h
[PdCl2(PhCN)2]
PCy3
80
aReaction conditions: 1a (0.2 mmol), 2a (0.4 mmol), Pd catalyst (5
mol %), ligand (10 mol %), Na2CO3 (0.4 mmol), and solvent (2 mL),
b
100 °C, under N2. GC yields with N,4ꢀdimethylbenzenesulfonamide
as the internal standard; isolated yields are given in parentheses.
c80 °C. d60 °C.
To test the validity of the proposed Suzuki coupling, we iniꢀ
tially chose N,N,Nꢀtrimethylꢀ1,1ꢀdiphenylmethanaminium
triflate (1a) and phenylboronic acid (2a) as the model sustrates
for reaction condition optimization (Table 1). To our delight,
desired crossꢀcoupling product 3a was obtained in 45% yield
when the reaction was performed in the presence of PdCl2 (5
mol %), PPh3 (10 mol %), and Na2CO3 (2 equiv) in EtOH (2
ACS Paragon Plus Environment

The Journal of Organic Chemistry
Page 2 of 6
mL) (entry 1). Further optimization revealed that 1,2ꢀ
in this coupling reaction, providing a potential point for further
functionalization of the coupling product. When benꢀ
1
2
3
4
5
6
7
8
dichloroethane (DCE) was the best solvent and led to the
product triphenylmethane 3a in 82% yield (entries 2–6).
Shortening the reaction time from 24 h to 12 h did not signifiꢀ
cantly affect the yield, but further reduction led to a lower
yield (entries 7 and 8). Screening of the palladium catalyst
revealed that [PdCl2(PhCN)2] was the optimal choice (entries
8–16). The ligand also plays an essential role because no reacꢀ
tion was detected in the absence of a ligand or when PPh3 was
replaced with 2,2'ꢀbipyridine (Bpy) (entries 17 and 18). Furꢀ
ther investigation showed that PCy3 was the best ligand, leadꢀ
ing to the generation of desired product 3a in 94% yield (enꢀ
tries 19 and 20). Decreasing the reaction temperature to 80 °C
led to a better result (entries 21 and 22).
zo[d][1,3]dioxolꢀ5ꢀyl
boronic
acid
and
(6ꢀ
formylbenzo[d][1,3]dioxolꢀ5ꢀyl) boronic acid were employed
as substrates, the reactions provided the corresponding prodꢀ
ucts (3o and 3p) in good yields. Notably, the crossꢀcouplings
of polycyclic aromatic boronic acids with 1a proceeded to
afford the coupling products in high yields (3q–s). To our deꢀ
light, heteroaromatic boronic acids also showed good reactiviꢀ
ty (3t–x).
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
Reactions of a variety of diarylmethanaminium salts were
also effective under the optimized conditions. 1ꢀ(Naphthalenꢀ
2ꢀyl)ꢀ1ꢀphenylmethanaminium salt reacted with various arylꢀ
boronic acids to afford the corresponding products (4a–d) in
moderate to good yields. Moreover, the ꢀOMe group on diaꢀ
rylmethanaminium salt was tolerated in this reaction system,
albeit moderate yield of the desired product (4e) was observed.
The coupling reaction also proceeded smoothly with disubstiꢀ
tuted diarylmethanaminium salts to give the coupling products
(4f–h) in good yields.
Scheme 1. Substrate Scopea
To demonstrate the practicality of the present strategy in the
synthesis of triarylmethane derivatives, a gramꢀscale synthesis
of 3a was performed, and a satisfactory yield (85% isolated
yield) was obtained under the standard conditions (eq 1). A
control
experiment
with
N,Nꢀdimethylꢀ1,1ꢀ
diphenylmethanamine 5a as the substrate failed to afford triꢀ
phenylmethane 3a under the standard reaction conditions (eq
2), suggesting that the C
salt is “activated.”
─N bond in the quaternary ammonium
Scheme 2. Proposed Reaction Mechanism
aReaction conditions: 1 (0.2 mmol), 2 (0.4 mmol), [PdCl2(PhCN)2] (5
mol %), PCy3 (10 mol %), and Na2CO3 (0.4 mmol) in DCE (2 mL) at
80 °C for 12 h. Isolated yields are given.
With the optimized reaction conditions in hand, the subꢀ
strate scopes with respect to both arylboronic acids and diaꢀ
rylmethanaminiums were examined. As shown in Scheme 1, a
series of arylboronic acids, including those with electronꢀ
donating groups (ꢀMe and ꢀOMe) and others with electronꢀ
withdrawing groups (ꢀF, ꢀCl, ꢀCN, ꢀCF3, ꢀCHO, and ꢀPh), were
converted into the corresponding products in good to excellent
yields (3b–l). Moreover, 3ꢀnitrophenylboronic acid was tolerꢀ
ated, and coupling product 3m was obtained in 89% yield. In
addition, the reactive vinyl functional group (3n) is conserved
ACS Paragon Plus Environment

Page 3 of 6
The Journal of Organic Chemistry
129.5, 128.3, 126.3, 56.9 ppm; MS (EI) m/z 77, 115, 152, 165,
244.
A tentative mechanism for this transformation is shown in
1
2
3
4
5
6
7
8
Scheme 2. Firstly, the oxidative addition of Pd(0), formed in
situ from Pd(II) under the action of phosphine ligand and base,
with diphenylmethanaminium salt 1a produces alkylpalladium
complex A. Then, a new palladium complex B is produced via
transmetalation of complex A with an arylboronic acid,
meanwhile trimethylamine was released. Finally, reductive
elimination of complex B affords product 3a with the simultaꢀ
neous regeneration of Pd(0). To provide some evidence, the
reaction was monitored by ESIꢀMS analysis and the correꢀ
sponding palladium complex A and B could all be detected
(for details, see the Supporting Information).
(oꢀTolylmethylene)dibenzene (3b).17 Yield 85% (43.8 mg); white
1
solid, Mp: 79−80 °C; TLC Rf = 0.61 (pure PE); H NMR (400
MHz, CDCl3) δ 7.26 (t, J = 6.8 Hz, 4H), 7.21−7.01 (m, 5H), 7.06
(d, J = 7.2 Hz, 4H), 6.82 (d, J = 7.2 Hz, 1H), 5.67 (s, 1H), 2.20 (s,
3H); 13C NMR (100 MHz, CDCl3) δ 143.5, 142.4, 136.7, 130.5,
129.7, 129.5, 128.3, 126.4, 126.3, 125.8, 53.6, 20.0 ppm; MS (EI)
m/z 77, 165, 181, 243, 258.
(pꢀTolylmethylene)dibenzene (3c).18 Yield 81% (41.8 mg); white
1
solid, Mp: 85−86 °C; TLC Rf = 0.75 (pure PE); H NMR (400
9
MHz, CDCl3) δ 7.27 (t, J = 6.8 Hz, 4H), 7.22−7.17 (m, 2H), 7.10
(t, J = 8.0 Hz, 6H), 7.01 (d, J = 8.0 Hz, 2H), 5.51 (s, 1H), 2.31 (s,
3H); 13C NMR (100 MHz, CDCl3) δ 144.2, 141.0, 135.8, 129.5,
129.4, 129.0, 128.3, 126.2, 56.5, 21.0 ppm; MS (EI) m/z 77, 165,
181, 243, 258.
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
■ CONCLUSIONS
((3ꢀMethoxyphenyl)methylene)dibenzene (3d).17 Yield 75%
(41.1 mg); white solid, Mp: 66−67 °C; TLC Rf = 0.45 (pure PE);
1H NMR (400 MHz, CDCl3) δ 7.27 (t, J = 7.2 Hz, 4H), 7.22−7.08
(m, 7H), 6.76 (dd, J = 2.4 Hz, J = 8.4 Hz, 1H), 6.72 (dd, J = 0.8
Hz, J = 7.6 Hz, 1H), 6.67 (s, 1H), 5.51 (s, 1H), 3.72 (s, 3H); 13C
NMR (100 MHz, CDCl3) δ 159.6, 145.6, 143.8, 129.4, 128.5,
128.3, 126.3, 122.0, 115.6, 111.4, 56.9, 55.1 ppm; MS (EI) m/z
77, 152, 165, 197, 243, 274.
In summary, we have developed an efficient and useful palꢀ
ladiumꢀcatalyzed Suzuki coupling of N,N,Nꢀtrimethylꢀ1,1ꢀ
diarylmethanaminium triflates with arylboronic acids through
C─N bond cleavage. This reaction, which shows good funcꢀ
tional group tolerance, provides a convenient and practical
method for the synthesis of triarylmethanes in good to excelꢀ
lent yields. Further studies on the application of the triarylmeꢀ
thane products and the asymmetric version of this reaction are
currently underway in our laboratory.
((4ꢀMethoxyphenyl)methylene)dibenzene (3e).18 Yield 85%
1
(35.6 mg); colorless oil; TLC Rf = 0.47 (PE/EA = 20:1, v/v); H
NMR (400 MHz, CDCl3) δ 7.27 (t, J = 7.2 Hz, 4H), 7.21−7.15
(m, 2H), 7.11 (d, J = 7.2 Hz, 4H), 7.03 (d, J = 8.4 Hz, 2H), 6.83
(d, J = 8.8 Hz, 2H), 5.50 (s, 1H), 3.77 (s, 3H); 13C NMR (100
MHz, CDCl3) δ 158.1, 144.3, 130.4, 129.4, 128.6, 128.3, 126.2,
113.7, 56.1, 55.2 ppm; MS (EI) m/z 77, 153, 165, 197, 243, 274.
((2,6ꢀDimethylphenyl)methylene)dibenzene (3f).17 Yield 65%
■ EXPERIMENTAL SECTION
All reactions were carried out in ovenꢀdried glassware under
N2. All arylboronic acids were obtained from commercial sources.
All the reactions were monitored by thinꢀlayer chromatography
(TLC). Products purification was done using silica gel column
chromatography.
1
(35.4 mg); colorless oil; TLC Rf = 0.60 (pure PE); H NMR (400
1H/13C NMR spectra were recorded on Bruker Avance 400
MHz and Bruker AMX 400 MHz spectrometer at 400/100 MHz,
respectively, in CDCl3 unless otherwise stated, using either TMS
or the undeuterated solvent residual signal as the reference.
Chemical shifts are given in ppm and are measured relative to
CDCl3 or DMSOꢀd6 as an internal standard. Mass spectra were
obtained by the electrospray ionization timeꢀofꢀflight (ESIꢀTOF)
mass spectrometry and Waters Acquity UPLC Iꢀclass Xevo G2ꢀ
XS QTof mass spectrometry. GC yields were obtained with N,4ꢀ
dimethylbenzenesulfonamide as the internal standard. Flash colꢀ
umn chromatography purification of compounds was carried out
by gradient elution using ethyl acetate (EA) in light petroleum
ether (PE).
MHz, CDCl3) δ 7.26 (t, J = 6.8 Hz, 4H), 7.22−7.17 (m, 2H), 7.10
(d, J = 7.6 Hz, 5H), 7.03 (d, J = 7.2 Hz, 2H), 6.03 (s, 1H), 2.03 (s,
6H); 13C NMR (100 MHz, CDCl3) δ 142.3, 140.1, 137.8, 129.4,
129.4, 128.2, 126.7, 126.0, 51.4, 22.1 ppm; MS (EI) m/z 77, 152,
165, 257, 272.
((4ꢀFluorophenyl)methylene)dibenzene (3g).17 Yield 82% (41.9
1
mg); white solid, Mp: 59−60 °C; TLC Rf = 0.52 (pure PE); H
NMR (400 MHz, CDCl3) δ 7.27 (t, J = 7.2 Hz, 4H), 7.21−7.18
(m, 2H), 7.10−7.04 (m, 6H), 6.95 (d, J = 8.8 Hz, 2H), 5.52 (s,
1H); 13C NMR (100 MHz, CDCl3) δ 162.7 (d, J = 243.4 Hz),
143.8, 139.7, 139.7, 130.9 (d, J = 7.8 Hz), 130.7, 129.4, 128.4,
1265, 115.2 (d, J = 21.1 Hz), 56.1 ppm; 19F NMR (376 MHz,
CDCl3) δ −116.82 ppm; MS (EI) m/z 77, 165, 183, 262.
General experimental procedure for the synthesis of tri-
arylmethanes: A mixture of trimethylammonium salts (0.2
mmol, 1.0 equiv), arylboronic acids (0.4 mmol, 2.0 equiv),
[PdCl2(PhCN)2] (0.01 mmol, 5 mol %), PCy3 (0.02 mmol, 10 mol
%) and Na2CO3 (0.4 mmol, 2.0 equiv) were sequentially added in
an ovenꢀdried Schlenk tube equipped with a stirꢀbar. After the
addition of all soild reagents, a balloon filled with N2 was conꢀ
nected to the Schlenk tube via the side tube and purged 3 times.
Then the solvent DCE (2.0 mL) were added to the tube via a syꢀ
((4ꢀChlorophenyl)methylene)dibenzene (3h).8b Yield 78% (43.4
1
mg); white solid, Mp: 167−168 °C; TLC Rf = 0.67 (pure PE); H
NMR (400 MHz, CDCl3) δ 7.29−7.19 (m, 8H), 7.09 (d, J = 7.2
Hz, 4H), 7.04 (d, J = 8.8 Hz, 2H), 5.50 (s, 1H); 13C NMR (100
MHz, CDCl3) δ 143.4, 142.5, 132.2, 130.8, 129.4, 128.6, 126.6,
56.2 ppm; MS (EI) m/z 77, 165, 201, 243, 278.
4ꢀBenzhydrylbenzonitrile (3i).17 Yield 66% (35.5 mg); colorless
1
oil; TLC Rf = 0.52 (PE/EA = 20:1, v/v); H NMR (400 MHz,
o
CDCl3) δ 7.58 (d, J = 8.0 Hz, 2H), 7.31 (t, J = 6.8 Hz, 4H),
7.26−7.21 (m, 4H), 7.08 (d, J = 7.2 Hz, 4H), 5.58 (s, 1H); 13C
NMR (100 MHz, CDCl3) δ 149.5, 142.4, 132.1, 130.2, 129.3,
128.6, 126.9, 118.9, 110.3, 56.9 ppm; MS (EI) m/z 77, 152, 165,
190, 269.
ringe. The Schlenk tube was heated at 80 C for 12 h. After the
reaction was completion, the contents were cooled to room temꢀ
perature. The reaction was quenched by water and extracted with
ethyl acetate three times. The combined organic layers were dried
over anhydrous Na2SO4 and evaporated under vacuum. The deꢀ
sired products were obtained in the corresponding yields after
purification by flash chromatography on silica gel with petroleum
ether/ethyl acetate.
((4ꢀ(Trifluoromethyl)phenyl)methylene)dibenzene (3j).10 Yield
1
74% (46.2 mg); colorless oil; TLC Rf = 0.75 (pure PE); H NMR
(400 MHz, CDCl3) δ 7.54 (d, J = 8.0 Hz, 2H), 7.30 (t, J = 6.8 Hz,
4H), 7.25 (dd, J = 4.8 Hz, J = 7.2 Hz, 4H), 7.10 (d, J = 7.2 Hz,
4H), 5.59 (s, 1H); 13C NMR (100 MHz, CDCl3) δ 148.0, 143.0,
129.8, 129.4, 128.8 (q, J = 321.6 Hz, J = 270.2 Hz), 128.5, 126.7,
Triphenylmethane (3a).16 Yield 90% (43.9 mg); white solid,
1
Mp: 94−95 °C; TLC Rf = 0.76 (pure PE); H NMR (400 MHz,
CDCl3) δ 7.28 (t, J = 6.4 Hz, 6H), 7.23−7.18 (m, 3H), 7.12 (d, J =
6.8 Hz, 6H), 5.55 (s, 1H); 13C NMR (100 MHz, CDCl3) δ 143.9,
ACS Paragon Plus Environment

The Journal of Organic Chemistry
Page 4 of 6
125.3 (q, J = 7.5 Hz, J = 3.7 Hz), 56.7 ppm; 19F NMR (376 MHz,
1494, 1078, 745; MS (EI) m/z 77, 165, 217, 295; HRMS (ESI−
TOF): calcd. for C22H18N [M + H]+ 296.1434; found 296.1429.
4ꢀBenzhydryldibenzo[b,d]thiophene (3s). Yield 82% (57.4 mg);
CDCl3) δ ꢀ62.33 ppm; MS (EI) m/z 77, 165, 243, 312.
1
2
4ꢀBenzhydrylbenzaldehyde (3k).10 Yield 60% (32.6 mg); colorꢀ
1
1
less oil; TLC Rf = 0.65 (PE/EA = 10:1, v/v); H NMR (400 MHz,
white solid, Mp: 143−144 °C; TLC Rf = 0.30 (pure PE); H NMR
3
4
5
6
7
8
9
CDCl3) δ 9.98 (s, 1H), 7.81 (d, J = 8.4 Hz, 2H), 7.32 (t, J = 7.2
Hz, 6H), 7.25−7.22 (m, 2H), 7.11 (d, J = 6.8 Hz, 4H), 5.61 (s,
1H); 13C NMR (100 MHz, CDCl3) δ 191.9, 151.2, 142.8, 134.8,
130.1, 129.8, 129.4, 128.6, 126.7, 57.0 ppm; MS (EI) m/z 77, 152,
165, 243, 272.
(400 MHz, CDCl3) δ 7.98 (dd, J = 1.6 Hz, J = 7.2 Hz, 1H), 7.87
(d, J = 0.8 Hz, 1H), 7.81 (dd, J = 1.2 Hz, J = 6.8 Hz, 1H), 7.74 (d,
J = 8.0 Hz, 1H), 7.41−7.33 (m, 2H), 7.31 (t, J = 7.2 Hz, 4H),
7.24−7.20 (m, 3H), 7.17 (d, J = 7.2 Hz, 4H), 5.73 (s, 1H); 13C
NMR (100 MHz, CDCl3) δ 143.9, 140.6, 139.9, 137.6, 135.8,
135.5, 129.6, 128.6, 128.5, 126.7, 126.5, 124.3, 122.9, 122.7,
122.4, 121.7, 56.9 ppm; vmax(KBr)/cmꢀ1 3442, 3058, 1599, 1493,
1429, 1078, 718; MS (EI) m/z 77, 136, 165, 273, 350; HRMS
(APGC): calcd. for C25H18S [M]+ 350.1129; found 350.1131.
2ꢀBenzhydrylfuran (3t).23 Yield 72% (33.7 mg); white solid,
4ꢀBenzhydrylꢀ1,1'ꢀbiphenyl (3l).10 Yield 75% (48.0 mg); white
1
solid, Mp: 118−120 °C; TLC Rf = 0.40 (pure PE); H NMR (400
MHz, CDCl3) δ 7.57 (d, J = 7.2 Hz, 2H), 7.51 (d, J = 8.0 Hz, 2H),
7.40 (t, J = 7.2 Hz, 2H), 7.32−7.27 (m, 5H), 7.23−7.14 (m, 8H),
5.58 (s, 1H); 13C NMR (100 MHz, CDCl3) δ 143.9, 143.1, 140.9,
139.2, 129.9, 129.5, 128.8, 128.4, 127.2, 127.1, 126.4, 56.6 ppm;
MS (EI) m/z 77, 165, 243, 320.
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
1
Mp: 51−52 °C; TLC Rf = 0.28 (pure PE); H NMR (400 MHz,
CDCl3) δ 7.38 (d, J = 1.2 Hz, 1H), 7.32 (t, J = 7.6 Hz, 4H),
7.25−7.21 (m, 2H), 7.18 (d, J = 7.2 Hz, 4H), 6.31 (dd, J = 1.6 Hz,
J = 3.2 Hz, 1H), 5.91 (d, J = 3.2 Hz, 1H), 5.45 (s, 1H); 13C NMR
(100 MHz, CDCl3) δ 156.7, 141.9, 141.8, 128.8, 128.4, 126.7,
110.1, 108.3, 50.9 ppm; MS (EI) m/z 77, 91, 128, 157, 205, 234.
2ꢀBenzhydrylbenzofuran (3u).16 Yield 80% (45.4 mg); white
((3ꢀNitrophenyl)methylene)dibenzene (3m).19 Yield 89% (51.4
1
mg); yellow oil; TLC Rf = 0.30 (pure PE); H NMR (400 MHz,
CDCl3) δ 8.09−8.06 (m, 1H), 8.00 (s, 1H), 7.45−7.43 (m, 2H),
7.33 (q, J = 7.6 Hz, 4H), 7.25−7.23 (m, 2H), 7.11 (d, J = 7.2 Hz,
4H), 5.64 (s, 1H); 13C NMR (100 MHz, CDCl3) δ 148.5, 146.2,
142.4, 135.6, 129.3, 129.2, 128.7, 127.0, 124.2, 121.6, 56.5 ppm;
MS (EI) m/z 77, 107, 165, 242, 272, 289.
1
solid, Mp: 125−126 °C; TLC Rf = 0.72 (pure PE); H NMR (400
MHz, CDCl3) δ 7.46 (dd, J = 1.6 Hz, J = 6.8 Hz, 1H), 7.41 (d, J =
8.0 Hz, 1H), 7.33−7.29 (m, 4H), 7.27−7.15 (m, 8H), 6.26 (s, 1H),
5.58 (s, 1H); 13C NMR (100 MHz, CDCl3) δ 160.0, 155.2, 141.1,
128.9, 128.6, 128.5, 127.0, 123.8, 122.7, 120.7, 111.2, 105.7, 51.4
ppm; MS (EI) m/z 77, 178, 207, 284.
((4ꢀVinylphenyl)methylene)dibenzene (3n).20 Yield 30% (16.2
mg); colorless oil; TLC Rf = 0.48 (pure PE); 1H NMR (400 MHz,
CDCl3) δ 7.34−7.19 (m, 8H), 7.12 (dd, J = 7.2 Hz, J = 16.0 Hz,
6H), 6.73 (dd, J = 11.2 Hz, J = 17.6 Hz, 1H), 5.73 (dd, J = 0.8 Hz,
J = 17.6 Hz, 1H), 5.53 (s, 1H), 5.22 (dd, J = 0.8 Hz, J = 10.8 Hz,
1H); 13C NMR (100 MHz, CDCl3) δ 143.8, 143.6, 136.5, 135.7,
129.6, 129.4, 128.7, 128.3, 126.3, 126.2, 113.5, 56.6 ppm; MS
(EI) m/z 77, 165, 193, 270.
3ꢀBenzhydrylthiophene (3v).22 Yield 81% (40.5 mg); white solꢀ
id, Mp: 81−82 °C; TLC Rf = 0.65 (pure PE); 1H NMR (400 MHz,
CDCl3) δ 7.31−7.18 (m, 7H), 7.16 (d, J = 8.0 Hz, 4H), 6.87 (d, J =
4.8 Hz, 1H), 7.72 (s, 1H), 5.45 (s, 1H); 13C NMR (100 MHz,
CDCl3) δ 145.0, 143.9, 129.0, 128.8, 128.4, 126.5, 125.5, 122.8,
52.7 ppm; MS (EI) m/z 77, 129, 178, 217, 250.
5ꢀBenzhydrylbenzo[d][1,3]dioxole (3o).21 Yield 63% (36.3
mg); colorless oil; TLC Rf = 0.41 (pure PE); 1H NMR (400 MHz,
CDCl3) δ 7.29 (t, J = 7.6 Hz, 4H), 7.22−7.18 (m, 2H), 7.12 (d, J =
7.6 Hz, 4H), 6.73 (d, J = 8.0 Hz, 1H), 6.60 (d, J = 1.6Hz, 1H),
6.57 (dd, J = 1.6 Hz, J = 8.0 Hz, 1H), 5.91 (s, 2H), 5.46 (s, 1H);
13C NMR (100 MHz, CDCl3) δ 147.7, 146.0, 144.0, 138.0, 129.4,
128.3, 126.3, 122.5, 110.0, 108.0, 100.9, 56.5 ppm; MS (EI) m/z
77, 152, 211, 258, 298.
2ꢀBenzhydrylbenzo[b]thiophene (3w).16 Yield 92% (55.2 mg);
1
white solid, Mp: 120−121 °C; TLC Rf = 0.55 (pure PE); H NMR
(400 MHz, CDCl3) δ 7.71 (d, J = 7.6 Hz, 1H), 7.60 (d, J = 7.2 Hz,
1H), 7.32−7.22 (m, 12H), 6.85 (s, 1H), 5.70 (s, 1H); 13C NMR
(100 MHz, CDCl3) δ 148.9, 143.0, 140.1, 139.8, 133.9, 133.7,
129.1, 128.6, 127.0, 124.2, 124.0, 123.3, 123.3, 122.2, 53.0 ppm;
MS (EI) m/z 77, 165, 178, 223, 300.
6ꢀBenzhydrylbenzo[d][1,3]dioxoleꢀ5ꢀcarbaldehyde (3p). Yield
45% (28.4 mg); white solid, Mp: 148−150 °C; TLC Rf = 0.40
3ꢀBenzhydrylbenzo[b]thiophene (3x).16 Yield 93% (55.8 mg);
1
(PE/EA = 4:1, v/v); H NMR (400 MHz, CDCl3) δ 10.17 (s, 1H),
1
white solid, Mp: 70−72 °C; TLC Rf = 0.42 (pure PE); H NMR
7.35 (s, 1H), 7.29 (t, J = 7.2 Hz, 4H), 7.23−7.21 (m, 2H), 7.08 (d,
J = 7.2 Hz, 4H), 6.45 (s, 2H), 6.00 (s, 2H); 13C NMR (100 MHz,
CDCl3) δ 189.4, 152.3, 146.8, 143.5, 143.1, 129.5, 128.6, 128.4,
126.8, 110.9, 109.2, 102.0, 51.1 ppm; vmax(KBr)/cmꢀ1 3439, 1597,
1488, 1383, 1049, 750; MS (EI) m/z 77, 120, 152, 239, 298, 316;
HRMS (APGC): calcd. for C21H16O3 [M]+ 316.1099; found
316.1105.
(400 MHz, CDCl3) δ 7.82 (d, J = 8.0 Hz, 1H), 7.46 (d, J = 7.6 Hz,
1H), 7.28 (t, J = 7.6 Hz, 5H), 7.20−7.15 (m, 7H), 6.71 (d, J = 0.8
Hz, 1H), 5.73 (s, 1H); 13C NMR (100 MHz, CDCl3) δ 142.7,
140.8, 139.2, 138.6, 129.2, 128.6, 126.7, 125.2, 124.3, 124.0,
122.8, 122.8, 51.5 ppm; MS (EI) m/z 77, 165, 178, 223, 300.
2ꢀBenzhydrylnaphthalene (4a).10 Yield 77% (45.3 mg); white
1
solid, Mp: 76−77 °C; TLC Rf = 0.35 (pure PE); H NMR (400
1ꢀBenzhydrylnaphthalene (3q).22 Yield 88% (51.7 mg); white
MHz, CDCl3) δ 7.78−7.67 (m, 3H), 7.47 (s, 1H), 7.42−7.39 (m,
2H), 7.30 (t, J = 7.6 Hz, 5H), 7.22−7.18 (m, 2H), 7.16 (d, J = 7.2
Hz, 4H), 5.69 (s, 1H); 13C NMR (100 MHz, CDCl3) δ 143.8,
141.6, 133.5, 132.3, 129.6, 128.4, 128.2, 128.0, 127.9, 127.6,
126.5, 126.1, 125.7, 57.1 ppm; MS (EI) m/z 77, 127, 165, 215,
294.
1
solid, Mp: 134−135 °C; TLC Rf = 0.45 (pure PE); H NMR (400
MHz, CDCl3) δ 7.99 (d, J = 7.2 Hz, 1H), 7.86 (dd, J = 1.6 Hz, J =
7.6 Hz, 1H), 7.75 (d, J = 8.0 Hz, 1H), 7.41−7.33 (m, 3H),
7.28−7.19 (m, 6H), 7.12−7.10 (m, 4H), 6.96 (dd, J = 4.8 Hz, J =
6.0 Hz, 1H), 6.27 (s, 1H); 13C NMR (100 MHz, CDCl3) δ 143.8,
140.0, 134.0, 132.0, 129.7, 128.7, 128.4, 127.7, 127.4, 126.4,
126.1, 125.5, 125.3, 124.4, 53.2 ppm; MS (EI) m/z 77, 165, 202,
215, 294.
2ꢀ((3ꢀMethoxyphenyl)(phenyl)methyl)naphthalene (4b).11c Yield
69% (43.3 mg); colorless oil; TLC Rf = 0.33 (PE/EA = 16:1, v/v);
1H NMR (400 MHz, CDCl3) δ 7.79−7.68 (m, 3H), 7.48 (s, 1H),
7.42−7.40 (m, 2H), 7.26 (t, J = 8.0 Hz, 3H), 7.23−7.15 (m, 4H),
6.78−6.71 (m, 3H), 5.67 (s, 1H), 3.71 (s, 3H); 13C NMR (100
MHz, CDCl3) δ 159.7, 145.4, 143.6, 141.4, 133.4, 132.2, 129.6,
128.4, 128.1, 127.9, 127.9, 127.8, 127.6, 126.5, 126.0, 125.6,
122.2, 115.7, 111.5, 57.0, 55.2 ppm; MS (EI) m/z 77, 123, 215,
293, 324.
5ꢀBenzhydrylquinoline (3r). Yield 85% (50.2 mg); white solid,
1
Mp: 126−128 °C; TLC Rf = 0.57 (PE/EA = 1:1, v/v); H NMR
(400 MHz, CDCl3) δ 8.68 (dd, J = 1.2 Hz, J = 4.0 Hz, 1H), 8.11
(d, J = 8.4 Hz, 1H), 7.85 (d, J = 8.4 Hz, 1H), 7.40 (t, J = 8.0 Hz,
1H), 7.12−7.02 (m, 7H), 6.91 (d, J = 6.8 Hz, 4H), 6.82 (d, J = 7.2
Hz, 1H), 6.02 (s, 1H); 13C NMR (100 MHz, CDCl3) δ 149.9,
148.9, 143.2, 140.4, 132.7, 129.6, 128.8, 128.7, 128.6, 128.0,
127.1, 126.7, 121.0, 52.9 ppm; vmax(KBr)/cmꢀ1 3442, 2921, 1633,
2ꢀ((4ꢀFluorophenyl)(phenyl)methyl)naphthalene (4c).6f Yield
1
62% (38.7 mg); colorless oil; TLC Rf = 0.36 (pure PE); H NMR
ACS Paragon Plus Environment

Page 5 of 6
The Journal of Organic Chemistry
(400 MHz, CDCl3) δ 7.79−7.68 (m, 3H), 7.44−7.40 (m, 3H),
Corresponding Author
7.31−7.20 (m, 4H), 7.14−7.08 (m, 4H), 6.99 (t, J = 8.4 Hz, 2H),
5.67 (s, 1H); 13C NMR (100 MHz, CDCl3) δ 162.8 (J = 243.6 Hz),
143.6, 141.4, 139.5 (J = 3.2 Hz), 133.4, 132.3, 131.1, 131.0,
129.5, 128.5, 128.0, 127.9, 127.9, 127.8, 127.6, 126.6, 126.1,
125.8, 115.3 (J = 21.1 Hz), 56.2 ppm; 19F NMR (376 MHz,
CDCl3) δ −116.62 ppm; MS (EI) m/z 77, 127, 183, 215, 233, 312.
2ꢀ(Naphthalenꢀ2ꢀyl(phenyl)methyl)furan (4d). Yield 53% (30.1
mg); colorless oil; TLC Rf = 0.21 (pure PE); 1H NMR (400 MHz,
d−DMSO) δ 7.89−7.81 (m, 3H), 7.67 (d, J = 7.6 Hz, 2H),
7.50−7.47 (m, 2H), 7.39−7.31 (m, 3H), 7.26−7.23 (m, 3H), 6.43
(dd, J = 2.0 Hz, J = 3.2 Hz, 1H), 6.05 (d, J = 3.2 Hz, 1H), 5.75 (s,
1H); 13C NMR (100 MHz, CDCl3) δ 156.5, 143.0, 142.3, 140.0,
133.4, 132.3, 129.0, 128.5, 128.1, 127.9, 127.4, 127.2, 127.1,
126.7, 126.3, 110.9, 108.5, 50.3 ppm; vmax(KBr)/cmꢀ1 3421, 2255,
1655, 1025, 826, 764; MS (EI) m/z 77, 128, 178, 255, 284;
HRMS (APGC): calcd. for C21H16O [M]+ 284.1201; found
284.1205.
1
2
3
4
5
6
7
8
*Eꢀmail: zhaojf@jxnu.edu.cn
ORCID
Junfeng Zhao: 0000ꢀ0003ꢀ4843ꢀ4871
Notes
The authors declare no competing financial interests.
■ ACKNOWLEDGMENT
This work was supported by the National Natural Science Founꢀ
dation of China (21462023, 21762021), the Natural Science
Foundation of Jiangxi Province (20161BAB213069), and the
Science and Technology Project of Jiangxi Provincial Education
Department (GJJ150297, GJJ150324).
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
■ REFERENCES
(1) Bindal, R. D.; Golab, J. T.; Katzenellenbogen, J. A. Ab Initio
Calculations on Nꢀmethylmethanesulfonamide and Methyl
Methanesulfonate for the Development of Force Field Torsional
Parameters and Their Use in the Conformational Analysis of Some
Novel Estrogens. J. Am. Chem. Soc. 1990, 112, 7861–7868.
(2) Chen, C.ꢀS.; Chiou, C.ꢀT.; Chen, G. S.; Chen, S.ꢀC.; Hu, C.ꢀY.;
Chi, W.ꢀK.; Chu, Y.ꢀD.; Hwang, L.ꢀH.; Chen, P.ꢀJ.; Chen, D.ꢀS.; Liaw,
S.ꢀH.; Chern, J.ꢀW. StructureꢀBased Discovery of Triphenylmethane
Derivatives as Inhibitors of Hepatitis C Virus Helicase. J. Med. Chem.
2009, 52, 2716–2723.
(3) Duxbury, D. F. The Photochemistry and Photophysics of
Triphenylmethane Dyes in Solid and Liquid Media. Chem. Rev. 1993,
93, 381–433.
(4) (a) Shchepinov, M. S.; Korshun, V. A. Recent Applications of
Bifunctional Trityl Groups. Chem. Soc. Rev. 2003, 32, 170–180. (b)
Nakagawa, S.; Sakakibara, K.; Gotoh, H. Novel Degradation
Mechanism for Triarylmethane Dyes: Acceleration of Degradation
Speed by the Attack of Active Oxygen to Halogen Groups. Dyes
Pigments 2016, 124, 130–132.
(5) (a) Zheng, Z. P.; Zhang, Y. N.; Zhang, S.; Chen, J. Oneꢀpot Green
Synthesis of 1,3,5ꢀTriarylpentaneꢀ1,5ꢀdione and Triarylmethane
Derivatives as a New Class of Tyrosinase Inhibitors. Bioorg. Med.
Chem. Lett. 2016, 26, 795–798. (b) Singh, P.; Manna, S. K.; Jana, A.
K.; Saha, T.; Mishra, P.; Bera, S.; Parai, M. K.; Kumar, M. S.; Mondal,
S.; Trivedi, P.; Chaturvedi, V.; Singh, S.; Sinha, S.; Panda, G.
Thiophene Containing Trisubstituted Methanes [TRSMs] as Identified
Lead Against Mycobacterium Tuberculosis. Eur. J. Med. Chem. 2015,
95, 357–368.
(6) (a) Liao, H.ꢀH.; Chatupheeraphat, A.; Hsiao, C.ꢀC.; Atodiresei, I.;
Rueping, M. Asymmetric Brønsted Acid Catalyzed Synthesis of
Triarylmethanes—Construction of Communesin and Spiroindoline
Scaffolds. Angew. Chem., Int. Ed. 2015, 54, 15540–15544. (b) Huang,
Y.; Hayashi, T. Asymmetric Synthesis of Triarylmethanes by
2ꢀ((3ꢀMethoxyphenyl)(phenyl)methyl)furan (4e). Yield 52%
(27.5 mg); white solid, Mp: 108−110 °C; TLC Rf = 0.25 (PE/EA =
1
10:1, v/v); H NMR (400 MHz, CDCl3) δ 7.37 (d, J = 1.2 Hz,
1H), 7.31−7.16 (m, 6H), 6.79−6.76 (m, 2H), 6.73 (t, J = 2.0 Hz,
1H), 6.31 (dd, J = 2.0 Hz, J = 3.2 Hz, 1H), 5.93 (d, J = 3.2 Hz,
1H), 5.41 (s, 1H), 3.75 (s, 3H); 13C NMR (100 MHz, CDCl3) δ
159.7, 156.6, 143.4, 141.9, 141.7, 129.4, 128.7, 128.4, 126.8,
121.2, 114.8, 111.9, 110.1, 108.3, 55.1, 50.9 ppm; vmax(KBr)/cmꢀ1
3394, 3059, 2921, 1604, 1506, 1254, 1158, 800; MS (EI) m/z 77,
128, 157, 235, 264; HRMS (APGC): calcd. for C18H16O2 [M]+
264.1150; found 264.1152.
1ꢀ((4ꢀFluorophenyl)(phenyl)methyl)ꢀ3ꢀmethylbenzene
(4f).
Yield 70% (38.6 mg); white solid, Mp: 90−91 °C; TLC Rf = 0.57
(pure PE); 1H NMR (400 MHz, CDCl3) δ 7.29 (t, J = 7.6 Hz, 2H),
7.22−7.15 (m, 2H), 7.10−7.01 (m, 5H), 6.98−6.92 (m, 3H), 6.88
(d, J = 7.6 Hz, 1H), 5.48 (s, 1H), 2.28 (s, 3H); 13C NMR (100
MHz, CDCl3) δ 162.7 (J = 243.4 Hz), 143.9, 143.7, 139.8, 138.0,
130.9 (J = 7.8 Hz), 130.1, 129.4, 128.4, 128.3, 127.2, 126.4,
126.4, 115.17 (J = 21.0 Hz), 56.1, 21.5 ppm; vmax(KBr)/cmꢀ1 3059,
2921, 1604, 1506, 1254, 1158, 800; MS (EI) m/z 65, 165, 183,
261, 276; HRMS (APGC): calcd. for C20H17F [M]+ 276.1314;
found 276.1315.
4,4'ꢀ(Phenylmethylene)bis(chlorobenzene) (4g).24 Yield 63%
(39.4 mg); white solid, Mp: 121−122 °C; TLC Rf = 0.72 (pure
PE); 1H NMR (400 MHz, CDCl3) δ 7.31−7.21 (m, 7H), 7.07 (d, J
= 7.2 Hz, 2H), 7.02 (d, J = 8.8 Hz, 4H), 5.47 (s, 1H); 13C NMR
(100 MHz, CDCl3) δ 142.9, 142.0, 132.4, 130.7, 129.2, 128.6,
128.6, 126.8, 55.6 ppm; MS (EI) m/z 75, 120, 165, 199, 277, 312.
4,4'ꢀ((3ꢀMethoxyphenyl)methylene)bis(chlorobenzene)
(4h).
Yield 74% (50.7 mg); colorless oil; TLC Rf = 0.67 (PE/EA =
50:1, v/v); 1H NMR (400 MHz, CDCl3) δ 7.26−7.23 (m, 4H), 7.21
(d, J = 8.0 Hz, 1H), 7.03 (d, J = 8.4 Hz, 4H), 6.79 (q, J = 2.0 Hz, J
= 8.0 Hz, 1H), 6.66 (d, J = 7.6 Hz, 1H), 6.60 (s, 1H), 5.44 (s, 1H),
3.74 (s, 3H); 13C NMR (100 MHz, CDCl3) δ 159.7, 144.5, 141.8,
132.4, 130.6, 128.6, 128.5, 121.8, 115.6, 111.6, 55.5, 55.2 ppm;
vmax(KBr)/cmꢀ1 3482, 3048, 2955, 1606, 1489, 1296, 1091, 1014,
800; MS (EI) m/z 152, 165, 231, 307, 342; HRMS (APGC):
calcd. for C20H16Cl2O [M]+ 342.0578; found 342.0583.
RhodiumꢀCatalyzed
Enantioselective
Arylation
of
Diarylmethylamines with Arylboroxines. J. Am. Chem. Soc. 2015, 137,
7556–7559. (c) Tsuchida, K.; Senda, Y.; Nakajima, K.; Nishibayashi,
Y. Construction of Chiral Triꢀ and TetraꢀArylmethanes Bearing
Quaternary Carbon Centers: CopperꢀCatalyzed Enantioselective
Propargylation of Indoles with Propargylic Esters. Angew. Chem., Int.
Ed. 2016, 55, 9728–9732. (d) Wang, X.; Yu, D.ꢀG.; Glorius, F.
Cp*RhIIIꢀCatalyzed Arylation of C(sp3)ꢀH Bonds. Angew. Chem., Int.
Ed. 2015, 54, 10280–10283. (e) Nambo, M.; Crudden, C. M. Recent
Advances in the Synthesis of Triarylmethanes by Transition Metal
Catalysis. ACS Catal. 2015, 5, 4734–4742 and references cited therein.
(f) Harris, M. R.; Hanna, L. E.; Greene, M. A.; Moore, C. E.; Jarvo, E.
R. Retention or Inversion in Stereospecific NickelꢀCatalyzed Crossꢀ
Coupling of Benzylic Carbamates with Arylboronic Esters: Control of
Absolute Stereochemistry with an Achiral Catalyst. J. Am. Chem. Soc.
2013, 135, 3303–3306.
■ ASSOCIATED CONTENT
Supporting Information
The Supporting Information is available free of charge on the
ACS Publications website at http://pubs.acs.org.
Copies of 1H and 13C NMR spectra for all compounds
(7) (a) Niwa, T.; Yorimitsu, H.; Oshima, K. PalladiumꢀCatalyzed
Direct Arylation of Aryl(azaaryl)methanes with Aryl Halides
Providing Triarylmethanes. Org. Lett. 2007, 9, 2373–2375. (b) Saha,
T.; Kumar, M. S. L.; Bera, S.; Karkara, B. B.; Panda, G. Efficient
■ AUTHOR INFORMATION
ACS Paragon Plus Environment

The Journal of Organic Chemistry
Page 6 of 6
Access to Triarylmethanes through Decarboxylation. RSC Adv. 2017,
Borylation of Arylꢀ and Benzyltrimethylammonium Salts via C–N
Bond Cleavage. J. Org. Chem. 2016, 81, 14–24.
7, 6966–6971. (c) Tabuchi, S.; Hirano, K.; Satoh, T.; Miura, M.
Synthesis of Triarylmethanes by PalladiumꢀCatalyzed C–H/C–O
Coupling of Oxazoles and Diarylmethanol Derivatives. J. Org. Chem.
2014, 79, 5401–5411. (d) Lin, S.; Lu, X. Cationic Pd(II)/Bipyridineꢀ
Catalyzed Addition of Arylboronic Acids to Arylaldehydes. OneꢀPot
Synthesis of Unsymmetrical Triarylmethanes. J. Org. Chem. 2007, 72,
9757–9760. (e) Li, J.; Yang, S.; Wu, W.; Jiang, H. Recent Advances in
PdꢀCatalyzed CrossꢀCoupling Reaction in Ionic Liquids. Eur. J. Org.
Chem. 2018, 2018, 1284–1306.
(8) (a) Zhang, J.; Sha, S.ꢀC.; Bellomo, A.; Trongsiriwat, N.; Gao, F.;
Tomson, N. C.; Walsh, P. J. Positional Selectivity in C–H
Functionalizations of 2ꢀBenzylfurans with Bimetallic Catalysts. J. Am.
Chem. Soc. 2016, 138, 4260–4266. (b) Zhang, J.; Bellomo, A.;
Creamer, A. D.; Dreher, S. D.; Walsh, P. J. PalladiumꢀCatalyzed
C(sp3)–H Arylation of Diarylmethanes at Room Temperature:
Synthesis of Triarylmethanes via DeprotonativeꢀCrossꢀCoupling
Processes. J. Am. Chem. Soc. 2012, 134, 13765–13772.
1
2
3
4
5
6
7
8
(14) (a) Blakey, S. B.; MacMillan, D. W. C. The First Suzuki Crossꢀ
Couplings of Aryltrimethylammonium Salts. J. Am. Chem. Soc. 2003,
125, 6046–6047. (b) Reeves, J. T.; Fandrick, D. R.; Tan, Z.; Song, J. J.;
Lee, H.; Yee, N. K.; Senanayake, C. H. Room Temperature
PalladiumꢀCatalyzed Cross Coupling of Aryltrimethylammonium
Triflates with Aryl Grignard Reagents. Org. Lett. 2010, 12, 4388–
4391. (c) Meng, G.; Szostak, M. Sterically Controlled PdꢀCatalyzed
Chemoselective Ketone Synthesis via N–C Cleavage in Twisted
Amides. Org. Lett. 2015, 17, 4364–4367. (d) Meng, G.; Shi, S.;
Szostak, M. CrossꢀCoupling of Amides by N–C Bond Activation.
Synlett. 2016, 27, 2530–2540. (e) Liu. C.; Szostak, M. Twisted
Amides: From Obscurity to Broadly Useful TransitionꢀMetalꢀ
Catalyzed Reactions by N−C Amide Bond Activation. Chem. Eur. J.
2017, 23, 7157–7173.
(15) (a) Davis, H. J.; Mihai, M. T.; Phipps, R. J. Ion PairꢀDirected
Regiocontrol in TransitionꢀMetal Catalysis: A MetaꢀSelective C–H
Borylation of Aromatic Quaternary Ammonium Salts. J. Am. Chem.
Soc. 2016, 138, 12759–12762. (b) Phipps, R.; Türtscher, P.; Davis, H.
PalladiumꢀCatalysed CrossꢀCoupling of Benzylammonium Salts with
Boronic Acids under Mild Conditions. Synthesis 2017, 50, 793–802.
(c) Wang, T.; Yang, S.; Xu, S.; Han, C.; Guo, G.; Zhao, J. Palladium
Catalyzed Suzuki CrossꢀCoupling of Benzyltrimethylammonium Salts
via CꢀN Bond Cleavage. Rsc Adv. 2017, 7, 15805–15808.
(16) Nambo, M.; Ariki, Z. T.; CansecoꢀGonzalez, D.; Beattie, D. D.;
Crudden, C. M. Arylative Desulfonation of Diarylmethyl Phenyl
Sulfone with Arenes Catalyzed by Scandium Triflate. Org. Lett. 2016,
18, 2339–2342.
(17) Ji, X.; Huang, T.; Wu, W.; Liang, F.; Cao, S. LDAꢀMediated
Synthesis of Triarylmethanes by Arylation of Diarylmethanes with
Fluoroarenes at Room Temperature. Org. Lett. 2015, 17, 5096–5099.
(18) Pallikonda, G.; Chakravarty, M. Benzylic Phosphates in Friedel–
Crafts Reactions with Activated and Unactivated Arenes: Access to
Polyarylated Alkanes. J. Org. Chem. 2016, 81, 2135–2142.
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
(9) Nambo, M.; Yar, M.; Smith, J. D.; Crudden, C. M. The Concise
Synthesis of Unsymmetric Triarylacetonitriles via PdꢀCatalyzed
Sequential Arylation:
a New Synthetic Approach to Triꢀ and
Tetraarylmethanes. Org. Lett. 2015, 17, 50–53.
(10) Xia, Y.; Hu, F.; Liu, Z.; Qu, P.; Ge, R.; Ma, C.; Zhang, Y.; Wang,
J. PalladiumꢀCatalyzed Diarylmethyl C(sp3)–C(sp2) Bond Formation:
A New Coupling Approach toward Triarylmethanes. Org. Lett. 2013,
15, 1784–1787.
(11) (a) Yu, J.ꢀY.; Kuwano, R. SuzukiꢀMiyaura Coupling of
Diarylmethyl Carbonates with Arylboronic Acids:ꢁ A New Access to
Triarylmethanes. Org. Lett. 2008, 10, 973–976. (b) Nambo, M.;
Crudden, C. M. Modular Synthesis of Triarylmethanes through
PalladiumꢀCatalyzed Sequential Arylation of Methyl Phenyl Sulfone.
Angew. Chem., Int. Ed. 2014, 53, 742–746. (c) Matthew, S. C.;
Glasspoole, B. W.; Eisenberger, P.; Crudden, C. M. Synthesis of
Enantiomerically Enriched Triarylmethanes by Enantiospecific
Suzuki–Miyaura CrossꢀCoupling Reactions. J. Am. Chem. Soc. 2014,
136, 5828–5831.
(19) Olah, G. A.; Wang, Q.; Orlinkov, A.; Ramaiah, P. Chemistry in
(12) Wenkert, E.; Han, A.ꢀL.; Jenny, C.ꢀJ. NickelꢀInduced Conversion
of Carbonꢀnitrogen into Carbonꢀcarbon Bonds. OneꢀStep
Transformations of Aryl, Quaternary Ammonium Salts into
Alkylarenes and Biaryls. J. Chem. Soc., Chem. Commun. 1988, 975–
976.
Superacids.
14.
Superelectrophilic
Nitration
of
the
Triphenylcarbenium Ion. J. Org. Chem. 1993, 58, 5017–5018.
(20) Kuijpers, P. F.; Otte, M.; Dürr, M.; IvanovićꢀBurmazović, I.;
Reek, J. N. H.; de Bruin, B. A SelfꢀAssembled Molecular Cage for
SubstrateꢀSelective Epoxidation Reactions in Aqueous Media. ACS
Catal. 2016, 6, 3106–3112.
(21) Bowden, S. T.; Harris, W. E.; Roberts, D. I. 68. Free Radicals and
Radical Stability. Part III. Diphenylpiperonylmethyl and Phenylꢀpꢀ
anisyldiphenylylmethyl. J. Chem. Soc. 1939, 302–307.
(22) Huang, R.; Zhang, X.; Pan, J.; Li, J.; Shen, H.; Ling, X.; Xiong,
Y. Benzylation of Arenes with Benzyl Halides Synergistically
Promoted by in Situ Generated Superacid Boron Trifluoride
Monohydrate and Tetrahaloboric Acid. Tetrahedron 2015, 71, 1540–
1546.
(23) Yuan, F.ꢀQ.; Gao, L.ꢀX.; Han, F.ꢀS. PdCl2ꢀCatalyzed Efficient
Allylation and Benzylation of Heteroarenes under Ligand, Base/Acid,
and AdditiveꢀFree Conditions. Chem. Commun. 2011, 47, 5289–5291.
(24) Prakash, S. G. K.; Fogassy, G.; Olah, G. A. MicrowaveꢀAssisted
NafionꢀH Catalyzed Friedel–Crafts Type Reaction of Aromatic
Aldehydes with Arenes: Synthesis of Triarylmethanes. Catal. Lett.
2010, 138, 155–159.
(13) (a) Xie, L.ꢀG.; Wang, Z.ꢀX. NickelꢀCatalyzed CrossꢀCoupling of
Aryltrimethylammonium Iodides with Organozinc Reagents. Angew.
Chem., Int. Ed. 2011, 50, 4901–4904. (b) Maity, P.; Shackladyꢀ
McAtee, D. M.; Yap, G. P. A.; Sirianni, E. R.; Watson, M. P. Nickelꢀ
Catalyzed Cross Couplings of Benzylic Ammonium Salts and Boronic
Acids: Stereospecific Formation of Diarylethanes via C–N Bond
Activation. J. Am. Chem. Soc. 2013, 135, 280–285. (c) Yu, S.; Liu, S.;
Lan, Y.; Wan, B.; Li, X. RhodiumꢀCatalyzed C–H Activation of
Phenacyl Ammonium Salts Assisted by an Oxidizing C–N Bond: A
Combination of Experimental and Theoretical Studies. J. Am. Chem.
Soc. 2015, 137, 1623–1631. (d) GuisánꢀCeinos, M.; MartínꢀHeras, V.;
Tortosa, M. Regioꢀ and Stereospecific CopperꢀCatalyzed Substitution
Reaction of Propargylic Ammonium Salts with Aryl Grignard
Reagents. J. Am. Chem. Soc. 2017, 139, 8448–8451. (e) Ouyang, K.;
Hao, W.; Zhang, W. X.; Xi, Z. TransitionꢀMetalꢀCatalyzed Cleavage
of CꢀN Single Bonds. Chem. Rev. 2015, 115, 12045–12090. (f) Hu, J.;
Sun, H.; Cai, W.; Pu, X.; Zhang, Y.; Shi, Z. NickelꢀCatalyzed
ACS Paragon Plus Environment