Pd catalyzed insertion of alkynes into cyclic diaryliodoniums: A direct access to multi-substituted phenanthrenes

Article abstract of DOI:10.1039/c5ob01597a

Cyclic diaryliodoniums remain unexplored compared to linear iodoniums. In our current work, internal alkynes were for the first time applied to react with cyclic iodoniums, catalyzed by Pd, resulting in a [4 + 2] benzannulation. Our work offers a new strategy to synthesize multi-substituted phenanthrene derivatives which are not easily accessed by conventional methods.

Full text of DOI:10.1039/c5ob01597a

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DOI: 10.1039/C5OB01597A
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Pd Catalyzed Insertion of Alkynes into Cyclic Diaryliodoniums: A
Direct Access to Multi‐substituted Phenanthrenes
Received 00th January 20xx,
Accepted 00th January 20xx
Yongcheng Wu,a,b Fuhai Wu,b Daqian Zhu,a Bingling Luo,a Haiwen wang,c Yumin Hu,a Shijun
Wen,a,c* and Peng Huanga
DOI: 10.1039/x0xx00000x
Cyclic diaryliodoniums remain unexplored compared to linear iodoniums. In our current work, internal alkynes were for
the first time applied to react with cyclic iodoniums, catalyzed by Pd, resulting in a [4+2] benzannulation. Our work offers a
new strategy to synthesize multi‐substituted phenanthrene derivatives which are not easily accessed by conventional
methods.
www.rsc.org/
incorporated iodoarene could be employed for further
transformations to set up a cascade reaction. The synthesis of
aromatic rings still remains a challenge while the reported
Introduction
Phenanthrenes have attracted considerable attention due to
their vital molecular structure features in materials and
important pharmacological activity.1 A number of studies have
suggested that these compounds may be potential anti‐
inflammatory,2 anti‐tumour,3 and anti‐tubercular agents.4 Thus,
the synthesis of phenanthrenes are of highly importance, and
several synthetic strategies have been reported, including
methods have limitations including harsh conditions, multi‐
steps reactions, and low yields.12‐16 We are interested in the
development of synthetic methods to build aromatic rings in
one pot with cyclic diaryliodoniums.17 Recently, we
demonstrated that terminal alkynes were easily arylated by
cyclic iodoniums, and then underwent further subsequent
transformation to exclusively form a five member ring,
benzyne‐alkyne‐benzyne
insertion,5
intramolecular
generating fluorenes
A
(Scheme 1).18 In this case, six
cyclizations,6 and [4+2] benzannulation reaction.7‐9 These
reported methods have some limitations, for example, either
harsh or sensitive reaction conditions, narrow substitutents in
the substrates, and toxicity of reagents. The [4+2]
cycloaddition is the most straightforward method for the
formation of phenanthrenes. Takahashi and co‐workers
demonstrated that aromatic phenanatrhenes were afforded by
using chromium reagents and butyllithium.7c Recently,
Nakamura reported that iron catalyzed [4+2] benzannulation
between alkyne and 2‐alkenylphenyl Grignard reagent.8 Both
of these two methods employed highly moisture sensitive
organometallic reagents, increasing the difficulty to operate
the reactions.
membered ring formation was not observed although the
intramolecular cyclization could make it happen. It is a
question raised thereof how to realize a six membered ring
formation with triple bonds. Heterocyclic ring formation with
internal alkynes mediated by transition metals has been
reported.19 We hypothesized that a six membered benzene
ring in phenanthrenes
C might be accessed while internal
alkynes were employed to replace terminal alkynes. In
principle, the insertion of internal alkynes into cyclic iodoniums
could generate intermediate species
B, and a potential
subsequent intramolecular coupling would form a middle six
membered ring. Herein, we report Pd catalyzed insertion of
internal alkynes into cyclic diphenyliodoniums featuring [4+2]
benzannulation to afford multi‐substituted phenanthrenes.
Compared to linear diaryliodoniums that are widely reported
as arylating reagents,10 cyclic diaryliodoniums have advantages
because their arylated products themselves incorporate the
iodoarenes which are inevitably produced and often discarded
in the arylation with linear diaryiodoniums.11 In addition, the
a. Sun Yat‐sen University Cancer Center, State Key Laboratory of Oncology in South
China, Collaborative Innovation Center for Cancer Medicine, 651 Dongfeng East
Road, Guangzhou 510060, China. E‐mail: wenshj@sysucc.org.cn
b. Guangdong Pharmaceutical University, 280 Waihuan East Road, Guangzhou
510006, China
c. School of Pharmaceutical Sciences, Sun Yat‐sen University, 132 Waihuan East
Road, Guangzhou 510006, China
Electronic Supplementary Information (ESI) available: The details of experiments,
characterisation of synthetic compounds, and copies of NMR spectra are available.
See DOI: 10.1039/x0xx00000x
Scheme 1. The strategies to employ alkenes/alkynes to react with cyclic iodoniums.
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alkynes also underwent well [4+2] benzannulation reactions to
generate the expected phenanthrenes (3f‐3k). To our more
delight, aliphatic alkynes were also successfully transformed to
the expected products smoothly (3l‐3n).
Results and discussion
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DOI: 10.1039/C5OB01597A
To validate our hypothesis, alkyne 1a and cyclic iodonium 2a
were employed at the outset of our study to investigate
whether their reaction could generate a known compound, 9‐
ethyl‐10‐phenylphenantrhene 3a 7c
. We were delighted to find
that 3a was obtained albeit at a low yield while using Pd(OAc)2
as a catalyst in 1,2‐dichloroethane (entry 1, table 1). Then, a
series of polar and non‐polar solvents were screened, with 1,
2‐dichloroethane still remaining the best (entry 1‐6). Further
study indicated that the addition of bases was not necessary
(entry 7). Moreover, additional zinc powder increased the yield
of products obviously, implying that a reducing agent can
accelerate the regeneration of palladium zero species (entry 8).
A number of phosphine ligands were then screened, and
tricyclohexylphosphine was found to significantly enhance the
yield (entry 13). Not surprisingly, the yield decreased when Zn
was withdrawn, confirming that Zn played a crucial role in the
reactions (entry 14). In addition, Cu, another reductive metal
also improved the yield, albeit not as much as zinc. The yield
slightly decreased when temperature was decreased to 80
℃
(entry 16).
Table 1. Optimization of the reaction conditions a
Pd(OAc)2
ligand
+
additive
solvent
I
OTf
2a
1a
3a
Entry
1
2
3
4
5
6
7
8
Ligand
PPh3
PPh3
PPh3
PPh3
PPh3
PPh3
PPh3
PPh3
dppe
dppf
Bu3P
P(NMe2)3
PCy3
PCy3
PCy3
PCy3
Solvent Additive
Yield (%)b
32
trace
20
DCE
i‐PrOH
DMF
DMSO
NMP
toluene
DCE
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
Na2CO3
‐
Figure 1. The scope of alkynes. Reaction condition: 1 (1.0 equiv), 2a (1.2 equiv), and
Pd(OAc)2 (10 mol %), PCy3 (0.3 equiv), Zn (1 equiv), Ar, DCE, 100℃, 15 h.
21
27
ND
37
47
30
51
48
53
82
50
63
62
Next, a range of cyclic diaryliodoniums with different
substituents were investigated to react with alkyne 1h (Figure
2). Under the standard reaction conditions, the iodoniums
with either electron donating or electron drawing groups
attached were all transformed to the desired phenanthrenes
at modest or good yields.
DCE
Zn
9
DCE
Zn
10
11
12
13
14
15
16c
DCE
Zn
DCE
Zn
DCE
Zn
DCE
Zn
DCE
‐
DCE
Cu
DCE
Zn
a 1a (1.0 equiv), 2a (1.2 equiv), Pd(OAc)2 (10 mol %), ligand (0.3 equiv), with or
without additive (1.0 equiv) , Ar, 100 oC, 15 h. b Isolated yield. c 80 oC. Notes: DCE,
1,
2‐dichloroethane;
NMP,
N‐methyl‐2‐pyrrolidone;
dppe,
1,2‐Bis‐
(diphenylphosphino)‐ethane; dppf, 1,1'‐Ferrocenebis‐diphenylphosphine; ND, not
detected.
With the optimal reaction conditions obtained, a variety of
internal alkynes were investigated to react with the iodonium
2a (Figure 1). The desired phenanthrenes were successfully
obtained at modest to good yields while aryl alkyl alkynes
were employed (3a‐3e). A number of functional groups were
compatible, including ester, amides and TMS (3b‐3e) to be
subject to the reaction conditions, providing opportunities for
further functionalization of these phenanthrenes. Diaryl
2 | J. Name., 2012, 00, 1‐3
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R1
R2
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Pd(OAc)2
PCy3
DOI: 10.1039/C5OB01597A
R2
R1
+
Zn, DCE
100 o
C
I
1h
OTf
2
3
O
F
Figure 3. The experiments to investigate the reaction mechanism
3q, 80%
3o, 89%
3r, 73%
3p, 84%
O
O
F
Based on our above observation and previous work,17a
a
F
F
probable pathway involving a Pd (0/II/IV) catalytic cycle is
proposed although the exact mechanism still needs to be
further investigated (Scheme 3). First, the palladium reactive
3u, 67%
3v, 75%
3s
, 61%
3t, 83%
species
F
was formed via oxidative addition of cyclic
with Pd (0) in situ reduced from Pd (II). Then, the
to the internal alkynes afforded intermediate
subsequent intermolecular oxidative
addition to form Pd (IV) species . It is worth‐mentioning that
palladium species was easily produced even at low
temperature. However, on one hand, the failure to obtain
intermediate in the above experiments implied that the
formation of palladium species from required a high
energy and had to be realized at high temperature. This might
liodoniums
insertion of
that underwent
2
F
1
G
a
3w, 70%
H
F
Figure 2. The scope of diaryliodoniums. Reaction conditions: 1a (1.0 equiv), 2a (1.2
equiv), and Pd(OAc)2 (10 mol %), PCy3 (0.3 equiv), Zn (1 equiv), Ar, DCE, 100℃, 15 h.
7
G
F
In our previous report, the reaction of cyclic diaryliodoniums
with indoles was able to generate dibenzocarbazoles (Scheme
2).17a The 2,3‐double bond of indoles acted as nucleophiles to
proceed dual arylations. The final result of the reaction was
the formation of a six membered benzene ring in a [4+2]
pathway. A palladium species cycle with Pd(II/IV) was
proposed therein for the transformation. However, the
potential mechanism of our current reactions between the
iodoniums and internal alkynes are believed to be different
although resulting in the same six membered ring formation.
explain why only
6 was obtained from palladium species F at
60 oC (Figure 3). On the other hand, the formation of 5 was not
observed in our above experiments. The result demonstrated
that the formation of
generated at higher temperature. A final reductive elimination
of resulted in phenanthrene . The generated palladium
H from G was rapid once species G was
H
3
species after one reaction cycle is two valent, and it has to be
reduced by reducing environments to regenerate Pd (0) for
next reaction cycle. This was validated by the fact that
additional metal zinc favoured the reactions.
Scheme 2. Our previous work on the reaction of iodoniums and indoles.
To explore the mechanism of the reactions, two experiments
were designed (Figure 3). Firstly, 4‐methoxyphenylboronic acid
was added additionally under the standard conditions to study
whether the intermediate
by the boronic acid to access
acid self coupled product were observed, demonstrating that
B
in scheme 1 could be intercepted
5. However, only 3a and boronic
4
intramolecular cyclization was faster than an intermolecular
coupling reaction with incoming boronic acid after in situ
generation of a potential palladiums species. Secondly, it was
Scheme 3. Proposed mechanism of the reaction.
also of our interest whether an intermediate
generate while the reaction was performed at lower
temperature to prevent the subsequent cyclization. However,
7 was able to
Experimental
General information for the experiments: All reaction under
standard conditions were carried out under argon atmosphere
and monitored by thin layer chromatography. All the
commercial available reagents, catalysts, and solvents and
were without further purification unless stated otherwise. All
only 2‐iodobiphenyl
and 2a were subjected to 60 C, implying that the generation
of required high energy.
6 was obtained while the mixture of 1a
o
B
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cyclic diaryliodoniums were prepared according to our Trimethyl‐(10‐phenylphenanthren‐9‐yl)‐silane
(3e)7c
:
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DOI: 10.1039/C5OB01597A
previous work18. All products were purified by silica gel (200‐ Obtained from 1e and 2a following the procedure for the
300 mesh) column chromatography with petroleum ether (60‐ synthesis of 3a. 1H NMR (400 MHz, CDCl3) δ 8.82 – 8.69 (m, 3H),
90
℃
) and dichloromethane as eluents. 1H and 13C spectra 8.32 (d, J = 8.0 Hz, 1H), 7.92 (t, J = 8.0 Hz, 1H), 7.55‐7.51 (m,
were recorded in CDCl3 or DMSO‐d6 on Bruker Avance 400 1H), 7.50 – 7.44 (m, 3H), 7.42 (d, J = 3.6 Hz, 2H), 7.38‐7.35 (m,
spectrometer. Chemical shifts are given in ppm (δ) referenced 2H), 0.10 (s, 9H). 13C NMR (101 MHz, CDCl3) δ 131.8, 131.5,
1
to CDCl3 with 7.26 for H and 77.16 for 13C, and to DMSO‐d6 130.2, 129.7, 128.8, 128.4, 128.0, 127.9, 127.6, 127.5, 126.9,
1
with 2.50 for H and 39.5 for 13C. Signals are abbreviated as 126.4, 125.8, 125.7, 123.2, 122.6, 122.3, 2.8.
follows: s, singlet; dd, doublet of doublets; d, doublet; t, triplet; 9, 10‐Diphenylphenanthrene (3f)14: Obtained from 1f and 2a
1
q, quartet; m, multiplet.
following the procedure for the synthesis of 3a. H NMR (400
9‐Ethyl‐10‐phenylphenanthrene (3a)7c: To a sealed tube with MHz, CDCl3) δ 8.82 (d, J = 8.4 Hz, 2H), 7.67 (m, 2H), 7.56 (m,
an magnetic stirrer bar, was added 1a (60 mg, 460 mol), 2a 2H), 7.49 (m, 2H), 7.25 – 7.22 (m, 4H), 7.22 – 7.19 (m, 2H), 7.17
(237 mg, 553
mol), Pd(OAc)2 (10 mg, 10 % mol), PCy3 (39 mg, (d, J = 1.6 Hz, 2H), 7.15 (t, J = 1.6 Hz, 2H). 13C NMR (101 MHz,
128 mol), Zn (30 mg, 460 mol) and 1,2‐dichloroethane (3 CDCl3) δ 139.7, 137.3, 132.0, 131.2, 130.1, 128.0, 127.7, 126.7,
mL). The reaction proceeded at 100
the mixture was diluted with CH2Cl2 and filtered via celite. The 9‐Phenyl‐10‐(
μ
μ
μ
μ
℃
for 15 h under Ar before 126.6, 126.5, 122.6.
p
‐tolyl)phenanthrene (3g)13: Obtained from 1g
1
filtrate was concentrated in vacuo and the crude product was and 2a following the procedure for the synthesis of 3a. H
purified by column chromatography on silica gel (petroleum NMR (400 MHz, CDCl3) δ 8.81 (d, J = 8.4 Hz, 2H), 7.66 (t, J = 7.6
ether/CH2Cl2 = 20/1) to give 3a (109 mg, 82% yield) as a white Hz, 2H), 7.61 – 7.43 (m, 4H), 7.23 (m, 3H), 7.19‐7.13 (m, 2H),
solid. 1H NMR (400 MHz, CDCl3) δ 8.84 – 8.79 (m, 1H), 8.75 (d, 7.04 (s, 4H), 2.31 (s, 3H). 13C NMR (101 MHz, CDCl3) δ 139.8,
J = 8.3 Hz, 2H), 8.25 – 8.16 (m, 1H), 7.74 – 7.66 (m, 2H), 7.54 137.4, 137.3, 136.6, 136.0, 132.2, 132.1, 131.2, 131.0, 130.2,
(m, 4H), 7.43 (t, J = 7.6 Hz, 1H), 7.34 (t, J = 8.5 Hz, 3H), 2.93 (q, J 130.1, 128.5, 128.0, 127.9, 127.7, 126.7, 126.6, 126.5, 126.4,
= 7.5 Hz, 2H), 1.23 (t, J = 7.5 Hz, 3H).13C NMR (101 MHz, CDCl3) 122.6, 100.1, 21.3.
δ 140.6, 136.7, 136.1, 132.5, 130.7, 130.6, 130.2, 129.4, 128.5, 9, 10‐Di‐
127.7, 127.2, 126.9, 126.4, 126.2, 125.8, 125.3, 123.2, 122.4, following the procedure for the synthesis of 3a. H NMR (400
p
‐tolylphenanthrene (3h)13: Obtained from 1h and 2a
1
23.6, 15.4.
Ethyl‐10‐(
MHz, CDCl3) δ 8.82 (d, J = 8.4 Hz, 2H), 7.67 (t, J = 7.6 Hz, 2H),
p
‐tolyl)‐phenanthrene‐9‐carboxylate
(3b)12
:
7.60 (d, J = 8.0 Hz, 2H), 7.50 (t, J = 7.6 Hz, 2H), 7.08 (s, 8H), 2.35
Obtained from 1b and 2a following the procedure for the (s, 6H). 13C NMR (101 MHz, CDCl3) δ 137.3, 136.7, 135.9, 132.3,
synthesis of 3a. 1H NMR (400 MHz, CDCl3) δ 8.76 (d, J = 8.4 Hz, 131.0, 130.0, 128.5, 128.0, 126.6, 126.3, 122.6, 77.5, 21.3.
2H), 7.92 (d, J = 8.0 Hz, 1H), 7.79 – 7.57 (m, 4H), 7.51‐7.49 (m, 9‐(4‐Methoxyphenyl)‐10‐phenylphenanthrene
(3i)7c
:
1H), 7.32‐7.25 (m, 4H), 4.15 (q, J = 7.2 Hz, 2H), 2.46 (s, 3H), Obtained from 1i and 2a following the procedure for the
1.01 (t, J = 7.2 Hz, 3H). 13C NMR (101 MHz, CDCl3) δ 169.5, synthesis of 3a. 1H NMR (400 MHz, CDCl3) δ 8.81 (d, J = 8.3 Hz,
137.6, 136.6, 135.1, 131.1, 130.8, 130.7, 130.3, 129.9, 128.9, 2H), 7.66 (t, J = 7.5 Hz, 2H), 7.60 (d, J = 8.1 Hz, 1H), 7.55 (d, J =
128.1, 127.9, 127.5, 127.1, 126.9, 125.9, 122.9, 122.7, 61.3, 7.5 Hz, 1H), 7.52 – 7.48 (m, 2H), 7.24 (m, 3H), 7.16 (d, J = 6.8
21.5, 13.9.
‐phenyl‐10‐(
Hz, 2H), 7.07 (d, J = 8.6 Hz, 2H), 6.79 (d, J = 8.6 Hz, 2H), 3.79 (s,
N
p
‐tolyl)‐phenanthrene‐9‐carboxamide
(3c)
:
3H). 13C NMR (101 MHz, CDCl3) δ 158.1, 139.9, 137.6, 136.9,
Obtained from 1c and 2a following the procedure for the 132.3, 132.2, 132.0, 131.9, 131.1, 130.1, 130.0, 128.0, 127.9,
synthesis of 3a. 1H NMR (400 MHz, CDCl3) δ 8.77 (d, J = 8.4 Hz, 127.7, 126.7, 126.5, 126.4, 122.6, 113.1, 55.2.
2H), 8.17 (d, J = 8.0 Hz, 1H), 7.73 – 7.66 (m, 3H), 7.57 – 7.45 (m, 9‐(3‐Fluorophenyl)‐10‐phenylphenanthrene (3j)
:
Obtained
7H), 7.22 (t, J = 6.8 Hz, 4H). 13C NMR (101 MHz, CDCl3) δ 167.5, from 1j and 2a following the procedure for the synthesis of 3a
.
137.9, 137.3, 135.7, 133.4, 130.9, 130.8, 130.2, 129.1, 129.0, 1H NMR (400 MHz, CDCl3) δ 8.72 (d, J = 8.4 Hz, 2H), 7.59 (t, J =
128.9, 128.8, 128.7, 128.4, 128.2, 127.7, 127.4, 127.1, 126.5, 7.6 Hz, 2H), 7.50 – 7.37 (m, 4H), 7.17 (m, 3H), 7.07 (m, 3H),
125.0, 122.9, 122.8, 120.7, 119.9. HRMS (ESI, m/z) calcd for 6.86 (d, J = 7.6 Hz, 1H), 6.80 (d, J = 9.2 Hz, 2H). 13C NMR (101
C27H20NO (M + H+), 374.1545; found, 374.1555. MP: 109.1‐ MHz, CDCl3) δ 139.3, 137.5, 136.0, 131.8, 131.5, 131.0 (d, J =
110.8
℃
. IR (KBr) υ: 3056, 2826, 1693, 1682, 1256.
‐tolyl)‐phenanthrene‐9‐carboxamide (3d):
6.0 Hz), 130.2 (d, J = 9.2 Hz), 129.2 (d, J = 8.4 Hz), 128.0, 127.9,
127.8, 127.7, 127.1 (d, J = 2.8 Hz), 127.0, 126.9, 126.8, 126.7,
N
,
N
‐diethyl‐10‐(
p
Obtained from 1d and 2a following the procedure for the 122.7 (d, J = 7.6 Hz), 118.2 (d, J = 21.2 Hz), 113.6 (d, J = 20.8 Hz).
synthesis of 3a. 1H NMR (400 MHz, CDCl3) δ 8.76 (d, J = 8.4 Hz, HRMS (ESI, m/z) calcd for C26H17F (M+), 348.1314; found,
1H), 7.89 (d, J = 8.0 Hz, 1H), 7.74 – 7.58 (m, 5H), 7.53 – 7.46 (m, 348.1326. MP: 116.2‐117.3
℃. IR (KBr) υ: 3055, 2826, 1505,
2H), 7.43 (m, 2H), 7.35 (m , 1H), 3.91 (m, 1H), 3.26 – 3.13 (m, 1216.
1H), 2.93 (m, 1H), 2.78 (m, 1H), 0.82‐0.79 (m, 3H), 0.69‐0.67 (m, Ethyl‐4‐(10‐phenylphenanthren‐9‐yl)‐benzoate (3k): Obtained
3H). 13C NMR (101 MHz, CDCl3) δ 137.5, 131.5, 129.8, 128.9, from 1k and 2a following the procedure for the synthesis of 3a
128.0, 127.9, 127.8, 127.7, 127.4, 127.3, 127.2, 127.1, 127.0, 1H NMR (400 MHz, CDCl3) δ 8.87 (d, J = 8.0 Hz, 2H), 8.00 (d, J =
126.9, 126.5, 122.9, 122.7, 42.6, 37.6, 29.8, 13.9, 11.8. HRMS 7.6 Hz, 2H), 7.74 (m, 2H), 7.62 (d, J = 8.4 Hz, 1H), 7.55 (m, 3H),
(ESI, m/z) calcd for C25H24NO (M + H+), 354.1858; found, 7.34 – 7.26 (m, 5H), 7.20 (d, J = 6.8 Hz, 2H), 4.42 (q, J = 7.2 Hz,
.
354.1866. MP: 100.8‐101.7
℃
. IR (KBr) υ: 3056, 2823, 1671, 2H), 1.45 (t, J = 7.2 Hz, 2H). 13C NMR (101 MHz, CDCl3) δ 166.7,
1256.
144.8, 139.2, 137.3, 136.3, 131.8, 131.4, 131.2, 131.0, 130.2,
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130.1, 129.0, 128.7, 128.0, 127.9, 127.6, 126.9, 126.8, 126.7, 3H), 2.34 (s, 3H), 2.33 (s, 3H). 13C NMR (101 MHz, CDCl3) δ
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DOI: 10.1039/C5OB01597A
122.7, 122.6, 61.1, 14.5. HRMS (ESI, m/z) calcd for C29H23O2 (M 158.24, 137.89, 136.88, 136.83, 136.70, 135.8, 133.8, 131.3,
+ H+), 403.1698; found, 403.1681. MP: 107‐108.4
℃
. IR (KBr) υ: 130.9, 130.8, 130.1, 129.1, 128.8, 128.5, 128.4, 128.0, 126.4,
3056, 2980, 2823, 1715, 1378, 1256.
125.6, 124.4, 124.2, 122.0, 116.1, 109.1, 55.3, 21.4. HRMS (ESI,
Ethyl‐10‐methylphenanthrene‐9‐carboxylate (3l)14: Obtained m/z) calcd for C29H24O (M+), 388.1827; found, 388.1829. MP:
from 1l and 2a following the procedure for the synthesis of 3a
.
126.4‐127.9
℃
1H NMR (400 MHz, CDCl3) δ 8.71 (dd, J = 11.7, 8.4 Hz, 2H), 8.13 Methyl‐9, 10‐di‐
. IR (KBr) υ: 3056, 2956, 1255.
‐tolylphenanthrene‐2‐carboxylate (3s)
p
:
(d, J = 7.6 Hz, 1H), 7.67 (m, 5H), 4.59 (q, J = 7.2 Hz, 2H), 2.71 (s, Obtained from 1h and 2f following the procedure for the
3H), 1.49 (t, J = 7.2 Hz, 3H). 13C NMR (101 MHz, CDCl3) δ 127.4, synthesis of 3a. 1H NMR (400 MHz, CDCl3) δ 8.82 (m, 2H), 8.32
127.3, 127.2, 126.6, 125.3, 125.2, 123.1, 122.8, 61.6, 17.2, 14.5. (s, 1H), 8.25 (d, J = 8.4 Hz, 1H), 7.68 (t, J = 7.2 Hz, 1H), 7.59 (d, J
Diethyl‐phenanthrene‐9, 10‐dicarboxylate (3m)13: Obtained = 7.6 Hz, 1H), 7.54 (d, J = 7.2 Hz, 1H), 7.06 (m, 8H), 4.36 (q, J =
from 1m and 2a following the procedure for the synthesis of 7.2 Hz, 2H), 2.33 (s, 6H), 1.36 (t, J = 7.2 Hz, 3H). 13C NMR (101
3a. 1H NMR (400 MHz, CDCl3) δ 9.81 (d, J = 7.6 Hz, 1H), 8.14 – MHz, CDCl3) δ 166.9, 138.1, 137.8, 136.4, 136.2, 136.1, 135.9,
8.02 (m, 2H), 7.83 (d, J = 7.6 Hz, 1H), 7.71 (m, 3H), 7.59 – 7.49 133.2, 133.0, 131.9, 131.0, 130.9, 130.3, 129.5, 128.6, 128.5,
(m, 1H), 4.89 – 4.11 (m, 4H), 1.45 (m, 6H). 13C NMR (101 MHz, 128.3, 128.1, 127.7, 126.7, 126.1, 123.2, 122.3, 61.1, 21.4, 14.4.
CDCl3) δ 128.4, 127.7, 126.8, 122.9, 62.0, 14.3.
HRMS (ESI, m/z) calcd for C30H24O2 (M+), 416.1776;
Phenanthrene‐9, 10‐diylbis(methylene)‐diacetate (3n)20: found,416.1766. MP: 110.3‐112.2
Obtained from 1n and 2a following the procedure for the 2824, 1715, 1385, 1256.
℃. IR (KBr) υ: 3055, 2980,
synthesis of 3a. 1H NMR (400 MHz, CDCl3) δ 8.75 (d, J = 8.0 Hz, 2, 7‐Dimethyl‐9, 10‐di‐
p‐tolylphenanthrene (3t): Obtained
2H), 8.19 (d, J = 8.0 Hz, 2H), 7.70 (t, J = 8.0 Hz, 4H), 5.83 (s, 4H), from 1h and 2g following the procedure for the synthesis of 3a
.
2.09 (s, 6H). 13C NMR (101 MHz, CDCl3) δ 171.0, 131.1, 130.7, 1H NMR (400 MHz, CDCl3) δ 8.66 (d, J = 8.4 Hz, 2H), 7.47 (d, J =
130.5, 127.5, 127.4, 125.4, 123.1, 60.1, 21.1.
8.4 Hz, 2H), 7.33 (s, 2H), 7.05 (q, J = 8.0 Hz, 8H), 2.43 (s, 6H),
2‐methyl‐9, 10‐di‐
p
‐tolylphenanthrene (3o)15: Obtained from 2.35 (s, 6H). 13C NMR (101 MHz, CDCl3) δ 137.1, 136.9, 135.8,
1
1h and 2b following the procedure for the synthesis of 3a. H 135.7, 132.0, 131.0, 128.3, 128.0, 127.9, 127.4, 122.3, 21.8,
NMR (400 MHz, CDCl3) δ 8.78 (d, J = 8.0 Hz, 1H), 8.71 (d, J = 8.4 21.4. HRMS (ESI, m/z) calcd for C32H30 (M+), 386.2035; found,
Hz, 1H), 7.65 (m, 1H), 7.58 (m, 1H), 7.53 – 7.43 (m, 2H), 7.38 (s, 386.2044. MP: 129.8‐130.4
℃. IR (KBr) υ: 3054, 2823, 1694,
1H), 7.08 (s, 8H), 2.45 (s, 3H), 2.36 (s, 3H), 2.35 (s, 3H). 13C 1373, 1255.
NMR (101 MHz, CDCl3) δ 137.3, 137.1, 136.9, 136.8, 136.3, 2, 7‐Difluoro‐9, 10‐di‐
135.7, 132.3, 131.9, 131.0, 130.1, 128.5, 128.4, 128.1, 127.9, from 1h and 2h following the procedure for the synthesis of 3a
127.4, 126.2, 126.1, 122.5, 122.3, 21.8, 21.4, 21.3.
1H NMR (400 MHz, CDCl3) δ 8.68 (dd, J = 9.2, 5.6 Hz, 2H), 7.39
2‐(Tert‐butyl)‐9, 10‐di‐ ‐tolylphenanthrene (3p): Obtained (m, 2H), 7.18 (dd, J = 11.2, 2.8 Hz, 1H), 7.07 (d, J = 8.0 Hz, 4H),
from 1h and 2c following the procedure for the synthesis of 3a
7.00 (d, J = 8.0 Hz, 4H), 2.33 (s, 6H). 13C NMR (101 MHz, CDCl3)
1H NMR (400 MHz, CDCl3) δ 8.77 (dd, J = 13.6, 8.4 Hz, 2H), 7.76 δ 161.3 (d, J = 245.1 Hz), 136.4, 135. 9, 130.6, 128.7, 126.4,
p
‐tolylphenanthrene (3u): Obtained
.
p
.
(M, 1H), 7.70 – 7.55 (m, 3H), 7.47 (M, 1H), 7.09 (d, J = 2.8 Hz, 124.6 (d, J = 9.3 Hz), 115.6 (d, J = 24.2 Hz), 112.6 (d, J = 22.1 Hz),
8H), 2.36 (d, J = 1.6 Hz, 6H), 1.33 (s, 9H). 13C NMR (101 MHz, 21.4. HRMS (ESI, m/z) calcd for C28H20F2 (M+), 394.1533; found,
CDCl3) δ 149.3, 137.5, 137.2, 136.9, 136.7, 135.8, 135.7, 132.0, 394.1529. MP: 127.2‐128.9
℃. IR (KBr) υ: 3054, 2825 1505,
131.0, 130.9, 129.9, 128.4, 128.3, 127.9, 126.3, 126.2, 124.5, 1382, 1256, 1206.
123.8, 122.4, 122.3, 34.9, 31.4, 21.5, 21.4. HRMS (ESI, m/z) 2‐Fluoro‐7‐methyl‐9,
10‐di‐
p
‐tolylphenanthrene
(3v):
calcd for C32H30 (M+), 414.2348; found, 414.2359. MP:130.1‐ Obtained from 1h and 2i following the procedure for the
1
131.7
℃
. IR (KBr) υ: 3056, 2828, 1691, 1373, 1256.
synthesis of 3a. H NMR (400 MHz, CDCl3) δ 8.72 (dd, J = 9.2,
2‐Fluoro‐9, 10‐di‐
p
‐tolylphenanthrene (3q): Obtained from 1h 5.6 Hz, 1H), 8.60 (d, J = 8.4 Hz, 1H), 7.49 (d, J = 7.6 Hz, 1H), 7.43
1
and 2d following the procedure for the synthesis of 3a. H – 7.32 (m, 2H), 7.21 – 7.14 (m, 1H), 7.08‐7.00 (m, 8H), 2.42 (s,
NMR (400 MHz, CDCl3) δ 8.80 – 8.65 (m, 2H), 7.71 – 7.61 (m, 3H), 2.34 (d, J = 4.0 Hz, 6H). 13C NMR (101 MHz, CDCl3) δ 161.2
1H), 7.58 (d, J = 8.0 Hz, 1H), 7.49 (d, J = 7.6 Hz, 1H), 7.39 (m, (d, J = 244.6 Hz), 138.3, 136.8 (d, J = 3.6 Hz), 136.5, 136.3,
1H), 7.22 (m, 1H), 7.13 – 6.97 (m, 8H), 2.34 (s, 6H). 13C NMR 136.2, 136.1, 135.9, 133.5 (d, J = 8.3 Hz), 131. 9, 130.8, 128.6,
(101 MHz, CDCl3) δ 161.5 (d, J = 245.1 Hz), 138.5, 136.7 (d, J = 128.4, 127.7, 127.6, 126.7, 124.6 (d, J = 8.6 Hz), 122.3, 115.1 (d,
4.0 Hz), 136.4, 136.2 (d, J = 3.3 Hz), 136.1, 134.0 (d, J = 8.5 Hz), J = 23.9 Hz), 112.3 (d, J = 22.0 Hz), 21.8, 21.4, 21.3. HRMS (ESI,
131.8, 131.0, 130.8, 129.8, 128.6, 128.4, 128.2, 126.6, 125.3, m/z) calcd for C29H23F (M+), 399.1784; found, 390.1777. MP:
124.9 (d, J = 8.7 Hz), 122.4, 115.2 (d, J = 23.9 Hz), 112.4 (d, J = 113.6‐114.8
℃. IR (KBr) υ: 3056, 2825 1515, 1382, 1256.
22.2 Hz), 21.4. HRMS (ESI, m/z) calcd for C28H21F (M+), 1, 3‐Dimethyl‐9, 10‐di‐p‐tolylphenanthrene (3w): Obtained
376.1627; found, 376.1637. MP: 110.2‐111.5
3056, 2824 1505, 1375, 1256, 1206.
℃
. IR (KBr) υ: from 1h and 2j following the procedure for the synthesis of 3a
.
1H NMR (400 MHz, CDCl3) δ 8.74 (dd, J = 9.2, 5.6 Hz, 1H), 8.44
2‐Methoxy‐9, 10‐di‐p‐tolylphenanthrene (3r): Obtained from (s, 1H), 7.35 – 7.28 (m, 1H), 7.17 (s, 1H), 7.02‐6.99 (m, 4H),
1
1h and 2e following the procedure for the synthesis of 3a. H 6.97 – 6.81 (m, 6H), 2.57 (s, 3H), 2.31 (s, 3H), 2.28 (s, 3H), 1.86
NMR (400 MHz, CDCl3) δ 8.74 – 8.66 (m, 2H), 7.62 (t, J = 7.6 Hz, (s, 3H). 13C NMR (101 MHz, CDCl3) δ 140.0, 138.2, 137.0, 136.6,
1H), 7.54 (d, J = 8.0 Hz, 1H), 7.46 – 7.38 (m, 1H), 7.30 (dd, J = 135.9, 135.8, 135.7, 133.0, 131.3, 131.0, 130.9, 128.4, 127.8,
9.2, 2.4 Hz, 1H), 7.06 (s, 9H), 6.97 (d, J = 2.4 Hz, 1H), 3.74 (s, 125.4, 125.3, 120.9, 115.1, 114.8, 112.1, 111.9, 25.2, 21.7, 21.3.
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1‐3 | 5
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Organic & Biomolecular Chemistry
Page 6 of 6
ARTICLE
Journal Name
HRMS (ESI, m/z) calcd for C32H30 (M+), 386.2035; found,
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6 | J. Name., 2012, 00, 1‐3
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