Ru(II)-catalyzed β-carboline directed C-H arylation and isolation of its cycloruthenated intermediates

Article abstract of DOI:10.1021/acs.joc.5b00411

A Ru(II)-catalyzed C-H arylation approach has been developed utilizing β-carboline alkaloids as the directing group. Selective formations of diarylated products from moderate to excellent yields were accomplished. Broad substrate scope with excellent functional group tolerance for C1-phenyl/thienyl/PAHs-β-carbolines was demonstrated. X-ray crystal structure of cycloruthenated complex 2cr and no arylation reaction with model substrate 13 strongly suggests that N2 is the directing group than N9 in C1-aryl-β-carbolines. Catalytic properties and stability of the cycloruthenated complexes have been explored. Library of biologically relevant new β-carboline derivatives and isolation of its cycloruthenated intermediates are the highlights of this work.

Full text of DOI:10.1021/acs.joc.5b00411

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Article
Ru(II)-catalyzed beta-carboline directed C-H arylation
and isolation of its cycloruthenated intermediates
Subramani Rajkumar, Shanmugam Karthik, and Thirumanavelan Gandhi
J. Org. Chem., Just Accepted Manuscript • Publication Date (Web): 10 Apr 2015
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Ru(II)-catalyzed β-carboline directed C-H arylation and
isolation of its cycloruthenated intermediates
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Subramani Rajkumar,a Shanmugam Karthika and Thirumanavelan Gandhia,b*
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aMaterials Chemistry Division, School of Advanced Sciences, VIT University, Vellore 632014, Tamil Nadu,
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INDIA
bCentre for Nanomaterials, VIT University, Vellore 632014, Tamil Nadu, INDIA
velan.g@vit.ac.in (T. Gandhi)
ABSTRACT: A Ru(II)ꢀcatalyzed CꢀH arylation approach has been developed utilizing βꢀ
carboline alkaloids as the directing group. Selective formations of diarylated products from
moderate to excellent yields were accomplished. Broad substrate scope with excellent
functional group tolerance for C1ꢀphenyl/thienyl/PAHsꢀβꢀcarbolines was demonstrated. Xꢀ
ray crystal structure of cycloruthenated complex 2cr and no arylation reaction with model
subsrate 13 strongly suggests that N2 is the directing group than N9 in C1ꢀarylꢀβꢀcarbolines.
Catalytic properties and stability of the cycloruthenated complexes have been explored.
Library of biologically relevant new βꢀcarboline derivatives and isolation of its
cycloruthenated intermediates are the highlights of this work.
INTRODUCTION
Over the last few decades, transition metalꢀcatalyzed CꢀH bond functionalization has been
recognized as one of the more promising alternatives of traditional crossꢀcoupling reactions.1
Apart from being an alternative, the advancement in the area of CꢀH functionalization has
adored the synthesis of complex natural products, agrochemicals, polymers, and
pharmaceutical targets in terms of productivity and economic viability.2 Various directing
groups and different transition metals have been implemented targeting diverse
functionalizations.3 In this regard, arylation reactions are among the most acclaimed and
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wellꢀstudied approaches of CꢀC bond formation. Consequently, a protocol capable of
employing a biologically important scaffold as directing group will enrich the design of
complex molecules for both inꢀvivo and inꢀvitro processes.
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The βꢀcarboline alkaloid is a naturally occurring scaffold actively involved in biologically
active molecules4 such as antiꢀbacterial, antiꢀmalarial, antiꢀ inflammatory, antiꢀtumor, and
antiꢀHIV drugs (Figure 1).5 The structural resemblance of βꢀcarboline alkaloids (C1ꢀarylꢀβꢀ
carbolines) with 2ꢀphenylpyridine revealed its importance as a potential directing group.
The enhanced biological activity6 of the hetero(aryl)/alkenyl substituted βꢀcarboline core
at the C1 and/or C3 position motivated us to utilize such a scaffold in the generation of new
bioactive target molecules. Notably, the presence of N9 along with N2 may also participate
in CꢀH activation involving both 6ꢀ7 and 5ꢀmembered cycloruthenated intermediates.8 To
facilitate the formation of the cycloruthenated intermediate and subsequent CꢀH
functionalization, Ackermann,9 Dixneuf10 and other research group11 wisely utilized the
carboxylates as a coꢀcatalyst. Either bulky carboxylic acid or its ruthenium derivatives
proved to be very efficient catalyst to promote CꢀH functionalization. Herein, simple and
convenient βꢀcarboline directed orthoꢀarylation of C1ꢀ(hetero)aryl/PAHsꢀβꢀcarbolines by a
ruthenium catalyst has been demonstrated. Notably, the isolation of a series of stable
ruthenacycles under the standard condition revealed its role as an intermediate of this process.
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Figure 1. Representative natural products with C1 arylated βꢀcarboline backbone
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RESULTS AND DISCUSSION
Optimization of Ru(II)-catalyzed arylation
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We began our catalytic arylation studies by combining 1ꢀphenylꢀβꢀcarboline 1a (0.2 mmol)
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with PhBr 2a (0.5 mmol) in the presence of [RuCl2(pꢀcymene)]2 (5 mol %), base (0.5 mmol)
and additives (30 mol %) using solvents such as toluene, 1,4ꢀdioxane, NMP and water.
When the reaction was carried out in the absence of a ruthenium catalyst, predictably, there
was no conversion of starting material (Table 1, entry 1). Pleasingly, the [RuCl2(pꢀcymene)]2
(5 mol %) afforded the monoarylated and diarylated products, but in reduced conversion of
8% with an mono/di ratio of 75:25 (entry 2) in the presence of 0.5 mmol Cs2CO3, 30 mol %
of KOAc using toluene as the solvent (20 h). To circumvent this issue, we chose K2CO3 as
the base, resulting in an improved conversion 41% with an m/d ratio of 90:10 (entry 3).
Solvents other than NMP resulted in reduced yields. Thus toluene, 1,4ꢀdioxane and H2O
were not considered. Among a set of additives such as acetate salts, Nꢀheterocylic carbene,
phosphines (/oxides) and carboxylic acids, (entry 5ꢀ15) very promising results were obtained
from phosphines and carboxylic acids, exhibiting some selectivity on the monoꢀ and
diarylation reaction. Remarkably, the reaction of 1a and 2a (0.5 mmol) in the presence of
PPh3 (30 mol %) and 0.5 mmol of K2CO3 resulted in complete conversion with a reduction in
the m/d ratio of 69:31 (entry 6). Extending the concept of using phosphineꢀbased additives,
we attempted the reaction with O=PPh3, PCy3 and triꢀtertꢀbutylphosphonium
tetrafluoroborate (TTBP•HBF4). None of them exhibited improvement in the arylation
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selectivity (entry 8, 9 & 10).
Interestingly, when we used 1,3ꢀbisꢀ(2,6ꢀ
diisopropylphenyl)imidazolinium chloride (HIPrCl) more diarylated product was observed
with a m/d ratio of 21:79 (entry 5). Ackermann, and Dixneuf have shown significant
contribution in the field of Ru(II)ꢀcatalyzed arylation of (hetero)arene using carboxylic acids
as additives, prompted us to evaluate them in our system.9a,b,9h,i,10a,b Among a variety of
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Table 1. Optimization of arylation reactions
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monoaryl- diarylated
base
additives
solvent
entry
[Ru]
conv.
%
ated 4aad
3aad
1
2
ꢀ
K2CO3
Cs2CO3
K2CO3
K2CO3
K2CO3
K2CO3
K2CO3
K2CO3
K2CO3
K2CO3
K2CO3
K2CO3
K2CO3
K2CO3
K2CO3
K2CO3
K2CO3
K2CO3
K2CO3
K2CO3
K2CO3
KOAc
KOAc
KOAc
KOAc
HIPrCla
PPh3
Toluene
Toluene
Toluene
NMP
NMP
NMP
NMP
NMP
NMP
NMP
NMP
NMP
NMP
NMP
NMP
NMP
NMP
NMP
NMP
NMP
NMP
0
8
NR
75
NR
25
[RuCl2(pꢀcymene)]2
[RuCl2(pꢀcymene)]2
[RuCl2(pꢀcymene)]2
[RuCl2(pꢀcymene)]2
[RuCl2(pꢀcymene)]2
[RuCl2(pꢀcymene)]2
[RuCl2(pꢀcymene)]2
[RuCl2(pꢀcymene)]2
[RuCl2(pꢀcymene)]2
[RuCl2(pꢀcymene)]2
[RuCl2(pꢀcymene)]2
[RuCl2(pꢀcymene)]2
[RuCl2(pꢀcymene)]2
[RuCl2(p-cymene)]2
[RuCl2(benzene)]2
RuCl3.XH2O12
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5
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9
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21
41
86
90
100
85
100
97
88
100
100
100
100
100
100
85
90
10
54
46
21
79
69
31
b
PPh3
80
20
O=PPh3
PCy3
[(tꢀBu)3PH]BF4
PhCO2H
tꢀBuCO2H
MesCO2H
(1ꢀAd)CO2H
Ph2HCCO2H
Ph2HCCO2H
Ph2HCCO2H
Ph2HCCO2H
Ph2HCCO2H
Ph2HCCO2H
Ph2HCCO2H
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65
28
72
25
75
14 (10)c
11 (8)c
10
86 (81)c
89 (85)c
90
11
88
RuCl3.3H2O
Ru(DMSO)4Cl2
[Ru(COD)Cl2]n
RuCl2(PPh3)3
86
14
42
100
100
100
21
79
25
75
30
70
Unless otherwise mentioned, all of the reactions were carried out with 0.2 mmol of 1a, 0.5 mmol of 2a, 5.0 mol % [Ru],
0.5 mmol of base, 30.0 mol % of additives, and 1.5 ml of solvent in a sealed tube at 120 °C for 20 h under N2
atmosphere. HIPrCl = N,N′ꢀbisꢀ(2,6ꢀdiisopropyl phenyl)imidazolium chloride; 0.3 mmol of 2a and 12 h; cIsolated
a
b
yields; d Determined by GC; NR = No reaction
carboxylic acids, which including pivalic acid, benzoic acid, mesitylene carboxylic acid,
adamantane carboxylic acid and diphenyl acetic acid (entry 11ꢀ15), we found out that
adamantane carboxylic acid and diphenyl acetic acid were very effective in furnishing the
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diarylated product with a m/d ratio of 14:86 and 11:89, respectively. From an economic and
toxicity point of view, we have selected diphenyl acetic acid as the best choice. As far as a
catalyst is concerned, [RuCl2(pꢀcymene)]2 proved better than RuCl3.XH2O, RuCl3.3H2O,
[RuCl2(DMSO)4], [RuCl2(COD)]n and [RuCl2(PPh3)3], (entry 17ꢀ21) as the former revealed
improved yields. [RuCl2(pꢀcymene)]2 and [RuCl2(benzene)]2 showed very similar results in
the direct arylation studies. However, [RuCl2(pꢀcymene)]2 is the least expensive (Table 1,
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entry 15). Consistently in all these reactions, no Nꢀarylation of the indole ring in the
carboline is observed.13
βꢀ
Scope of Ru(II)-catalyzed arylation of C1-aryl-β-carbolines using arylbromides and
heterocyclic bromides
With the optimal conditions in hand, we have investigated the scope of the βꢀcarbolineꢀ
directed Ruꢀcatalyzed orthoꢀarylation of 1ꢀphenylꢀβꢀcarbolines using various aryl halides.
orthoꢀArylation using aryl iodides and aryl bromides showed promising results with good
yields, whereas aryl chlorides produced a very low yield (Table 2). Substituents such as tꢀ
Buꢀ 2b, MeCOꢀ 2d, MeOꢀ 2e, Me2Nꢀ 2f, and ꢀCN 2g at the para position in aryl bromides
were well tolerated under the reaction condition (Table 2). Interestingly, the various
heterocyclic bromides such as thiophene 2h, pyridine 2i, isoquinoline 2j, indole 2l and
carbazole 2m show smooth arylation without poisoning the catalyst (Table 3). In general,
diarylation proceeds smoothly irrespective of electron rich or electron poor aryl bromide
partners employed. Next, we tested the reactivity by introducing the various functional
groups such as methyl 1b, methoxy 1c, cyano 1d, fluoro 1e, and nitro 1f at the C4' position of
the phenyl ring in C1ꢀphenylꢀβꢀcarboline (Table 2 and 3). Functional groups such as ꢀCN14
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Table 2. Ru(II)ꢀcatalyzed arylation using aryl bromides
R1
5
R1
R1
5.0 mol %
[RuCl2(p-cymene)]2
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7
8
9
30 mol %
diphenyl acetic acid
Ar
Ar
Ar
+
Ar Br
+
NH
NH
NH
N
N
N
0.5 mmol K2CO3,
NMP
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120 oC, 20 h
4
3
2
1
isolated yields
(0.5 mmol)
(0.2 mmol)
R1
3ae
4ae -
- 85%
10%
R1
3be - 88%
3de - 89%
3ee - 90%
3fe - 43%
4fe - 42%
NH
N
O
NH
O
N
di-
mono-
arylated
- yielda
arylated
- yielda
3af - 81%
3bf - 92%
3cf - 89%
3df - 89%
3ef - 90%
3ff - 40%
PhI
PhBr =
=
3aa - 89%
3aa - 85%
4aa - 7%
4aa - 8%
4bf - 5%
4ff - 48%
R1
3aa - 81%b 4aa - 10%b
R1 = H
= CH3
1a PhCl =
4aa - 34%
4ba - 8%
3aa - 51%
3ba - 88%
3ca - 85%
3da - 92%
3ea - 90%
1b
= OCH3 1c
= CN
= F
= NO2
1d
1e
1f
N
NH
N
N
3ab - 91%
R1
4ag - 9%
4fg - 41%
3ag - 85%
NH
N
NC
CN
NH
N
R1
3ac - 90%
3bc - 87%
3an - 88%
NH
O
O
N
NH
N
O
3ad - 83%
4ad - 10%
O
3ad - 81%b 4ad - 7%b
R1
3bd - 88%
3cd - 81%
3dd - 92%
4bd - 4%
4cd - 8%
3ed - 89%
O
O
4fd - 32%
NH
N
1 (0.2 mmol), 2 (0.5 mmol), [RuCl2(pꢀcymene)]2 (5.0 mol %), K2CO3 (0.5 mmol), Ph2CHCO2H (30 mol %),
NMP, 120 °C, 20 h. Isolated yield. bIsolated yield (1ꢀAd)CO2H (30 mol %).
a
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Table 3. Ru(II)ꢀcatalyzed arylation using hetroaryl bromides
4
5
6
R1
R1
R1
5.0 mol %
[RuCl2(p-cymene)]2
7
8
9
30 mol %
diphenyl acetic acid
Het
Het
Het
+
+
Het-Br
NH
NH
NH
N
N
N
0.5 mmol K2CO3,
NMP
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60
120 oC, 20 h
4
3
2
1
isolated yields
(0.5 mmol)
(0.2 mmol)
R1
3ah - 76%
4ah - 18%
4bh - 12%
4ak - 10%
3ak - 78%
3bh - 82%
3dh - 81%
3eh - 88%
S
S
N
N
NH
NH
N
N
4al - 13%
3al - 80%
4ai - 9%
3ai - 85%
N
NH
N
N
NH
NH
H
N
N
NH
N
N
N
NH
NH
N
N
H
4aj - 19%
3aj - 75%
3am - 79%
4am - 18%
1 (0.2 mmol), 2 (0.5 mmol), [RuCl2(pꢀcymene)]2 (5.0 mol %), K2CO3 (0.5 mmol), Ph2CHCO2H (30 mol %),
a
NMP, 120 °C, 20 h. Isolated yield.
and ꢀNO215 are well known orthoꢀdirecting groups. However, these functional groups did not
participate in the CꢀH activation process even with 5 equiv of aryl bromides.
Synthesis and reactivity of cycloruthenated C1-aryl-β-carboline
The orthoꢀarylation reactions are expected to proceed via five or sixꢀmembered
cyclometalation intermediates. To confirm this, various cyclometalation intermediates were
synthesized by stoichiometric reaction of C1ꢀarylꢀβꢀcarboline and [RuCl2(pꢀcymene)]2 in the
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presence of KOAc (3 equiv) at room temperature (Scheme 1a). Cycloruthenation in C1ꢀarylꢀ
1
βꢀcarbolines complexes was determined by H NMR, i.e., by the disappearance of the ortho
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8
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hydrogen of the 1ꢀphenyl substituent. Additionally, the 13C NMR showed significantly
deshielded signals (ranging from δ = 176 – 196 ppm), which corroborated the existence of a
RuꢀC σꢀbond in the structure. Eventually, the representative cycloruthenated complex 2cr
depicting N2 of the βꢀcarboline coordinating to the ruthenium was unambiguously confirmed
by single crystal Xꢀray diffraction study (Figure 2). To confirm the reactivity of the isolated
cycloruthenated species, 1cr was reacted with PhBr (2.5 equiv), which resulted in diarylated
product in 96% yield (Scheme 1b). Such a reaction demonstrated that 1cr is catalytically
competent intermediate.16 However, when 1cr was used as a catalyst (5 mol %) resulted in
the decrease of selective arylation (Scheme 1c).
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Cycloruthenated C1ꢀarylꢀβꢀcarboline derivatives 1crꢀ8cr were quite stable in solvents like
methanol, dichloromethane and chloroform. However, in DMSO, they exhibit some
1
reactivity which was followed by H NMR (Figure 3). The chloride ion present in 1cr is
replaced by DMSO to form 9cr (Figure 3(2)) and eventually to 10cr (Figure 3(3)) with the
expulsion of η6ꢀpꢀcymene ligand (Scheme 2).
cycloruthenated moiety stays intact. Downfield peaks at δ 12.17 (ꢀ), δ 11.88 (ꢀ) and 11.75
ppm (ꢁ) in figure 3(2) corresponds to cycloruthenated ꢀcarboline NH moiety of 9cr, 10cr
Surprisingly, in the entire cases
β
and 1cr respectively. In 13C NMR, cycloruthenated carbon (i.e., RuꢀC) for 1cr and 10cr
appears at δ 183.27 and δ 177.35 ppm respectively. Presence of mixture of 1cr, 9cr and 10cr
was observed clearly on 7th day (Figure 3(2)), and subsequently on 14th day 1cr and 9cr was
transformed to 10cr (Figure 3(3)). Aromatic CꢀH’s and η6−pꢀcymene CꢀH’s in 9cr (ꢀ)
exhibited downfield shift compared to 1cr (ꢁ). Free pꢀcymene (ꢁ) expelled in the reaction
were identified and matched with the authentic sample, and compound 10cr was isolated and
characterized by 1H NMR, 13C NMR and mass spectrometry.
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R1
R1
R1 = H
= CH3
1cr
2cr
6
7
8
9
KOAc
[RuCl (p-cymene)]
1/2
2
2
= OCH3 3cr
= CN
= F
Ru
MeOH
a)
NH
4cr
5cr
6cr
NH
rt, 12 h
Cl
N
N
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= NO2
1-6a
1-6cr
2.5 equiv PhBr
30 mol %
diphenyl acetic acid
Ph
N
Ph
Ph
NH
Ru
+
b)
NH
NH
0.5 mmol K2CO3,
NMP
Cl
N
N
120 oC, 20 h
1cr
4aa - <3%
3aa - 96%
1cr (5 mol %)
30 mol %
diphenyl acetic acid
2b
c)
1a
+
3aa - 54%
4aa - 41%
+
0.5 mmol K2CO3,
NMP
120 oC, 20 h
Scheme 1. Synthesis and catalytic property of cycloruthenated C1ꢀphenylꢀβꢀcarbolines.
Figure 2: ORTEP diagram of Ru(II) complex 2cr (50 % probability ellipsoids). Hydrogen
atoms and solvent molecules are omitted for clarity
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ꢀ
ꢁ
Scheme 2. Reactivity of cycloruthenated C1ꢀphenylꢀβꢀcarboline derivative 1cr in DMSO
Figure 3. Stack plot of 1H NMR spectra of the reaction of 1cr with DMSOꢀd6 with time. (1)
1cr + DMSOꢀd6 on 1st day; (2) 1cr + DMSOꢀd6 on 7th day; (3) 1cr + DMSOꢀd6 on 14th day.
Insets were 13C NMR chemical shift of cycloruthenated carbon on 1st (1cr) and 14th day
(10cr). (ꢁ) 1cr, (ꢀ) 9cr, (ꢀ) 10cr and (ꢁ) free pꢀcymene.
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Role of N2 and N9 in C1-aryl-β-carbolines as a directing group
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In order to understand the role of N2 or N9 as a directing group in C1ꢀarylꢀβꢀcarbolines, we
8
9
have chosen a model substrate 13 (1ꢀPhenylꢀ9Hꢀcarbazole)17 which is devoid of N2.
Suprisingly, 13 remains unreactive in the arylation conditions, and even when arylbromide
were taken in large excess (5 equiv) (Scheme 3). Thus, this model study strongly suggests
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that N2 have great role in arylation of C1ꢀarylꢀ
βꢀcarbolines derivatives than N9. In addition,
the cycloruthanted complex 2cr also supports the role of N2 as directing group over N9.
Scheme 3. Tests of arylation in the absence of N2
Scope of Ru(II)-catalyzed C1-thienyl-
bromides
β-carboline using arylbromides and heterocyclic
We examined CꢀH arylation of C1ꢀthienylꢀβꢀcarboline 5 by reacting with various aryl
bromides 2a-2i. When 5 reacted with a stoichiometic amount of [RuCl2(pꢀcymene)]2 at room
temperature in the presence of KOAc, an isolable rollover cycloruthenated intermediate18 7cr
was generated, which was characterized by multinuclear NMR and mass spectrometry (Table
4). Catalytically, the ortho CꢀH bond in the 1ꢀthienyl moiety of 5 was activated and
functionalized to give various new C3ꢀarylated C1ꢀthienylꢀβꢀcarboline derivatives 6aꢀ6i in
good yields (Table 4). To the best of our knowledge, there is no report in the literature on the
C3ꢀarylation of 2ꢀ(thiophenꢀ2ꢀyl)pyridine scaffolds using ruthenium as a catalyst.
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Table 4. Ruꢀcatalyzed arylation of C1ꢀthienylꢀβꢀcarboline using (hetro)aryl bromides.
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Scope of Ru(II)-catalyzed C1-PAHs-β-carboline using arylbromides
Next, we utilized this protocol to activate and functionalize the ortho CꢀH of PAHs
(polyaromatic hydrocarbons) in C1ꢀPAHsꢀβꢀcarbolines (Table 5). The 2ꢀnapthyl starting
material 7 reacted with 2a and 2d to yield monoarylated products 8a and 8d via
cycloruthenated intermediate 8cr (see Supporting Information). Likewise, 10 reacted with 2d
to give 11d, but formation of 12d was not detected due to steric and energetically unfavorable
6ꢀmembered cycloruthenated intermediate formation.
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Table 5. Ruꢀcatalyzed arylation of C1ꢀPAHsꢀβꢀcarboline using aryl bromides
5
6
7
8
9a - trace
9d
5.0 mol %
[RuCl2(p-cymene)]2
8a -
8d - 65%
52%
- trace
30 mol %
diphenyl acetic acid
Ar
Ar
Ar
(a)
Ar-Br
9
NH
NH
NH
N
N
N
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0.5 mmol K2CO3,
NMP
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2
5.0 mol %
[RuCl2(p-cymene)]2
Br
30 mol %
diphenyl acetic acid
(b)
O
NH
NH
NH
N
N
N
O
0.5 mmol K2CO3,
NMP
120 oC, 20 h
O
O
12d
11d
- NR
- 70%
2d
10
Plausible mechanism for Ru(II)-catalyzed arylation
In accord with previous Ru(II)ꢀcatalyzed direct arylation reactions,1g,10c,16 we propose the
arylation pathway in Scheme 4. The sequential mechanism involve concertedꢀmetalation
deprotonation (CMD) C, cycloruthenated species D (crystallographically characterized),
oxidative addition i.e., Ru(IV) species E and reductive elimination to give the arylated
product. Isolation of cycloruthenated complexes 1crꢀ8cr further substantiated this pathway.
Scheme 4. Possible mechanism for Ruꢀcatalyzed arylation
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CONCLUSION
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In summary, we have demonstrated the effective utility of βꢀcarboline as a directing group in
Ru(II)ꢀcatalyzed orthoꢀarylation reactions. This approach is applicable in arylating
(hetero)aryl and polyaromatic hydrocarbons attached to the βꢀcarboline scaffold. Role of N2/
N9 in C1ꢀarylꢀβꢀcarbolines as a directing group was understood from model substrate 13 and
Xꢀray crystal structure 2cr. Besides, catalytic and stability studies of the cycloruthenated
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complex 1cr have been explored.
A series of cycloruthenated βꢀcarboline intermediates,
and a library of new functionalized C1ꢀhetero(aryl)/PAHsꢀβꢀcarbolines, have been
synthesised, which is expected to possess photophysical properties and biological value.
EXPERIMENTAL SECTION
General remarks
Unless otherwise mentioned, all the reactions were carried out under nitrogen purged screw
cap reaction tubes. All solvents and reagents were of pure analytical grade. Various
ruthenium catalysts were prepared from literature procedure.19 The products were purified by
column chromatography, silica gel (60ꢀ120 mesh or 200ꢀ420 mesh). A gradient elution using
petroleum ether and ethyl acetate was performed based on preꢀcoated aluminiumm TLC
sheets (silica gel 60F 254).
Analytical information
1
All isolated compounds were characterized by H, 13C and HRMS. Compound 2cr was
characterized by single crystal Xꢀray diffraction (Figure 1 & S1). Copies of the 1H NMR, 13C
NMR can be found in the supporting information. All Nuclear Magnetic Resonance Spectra
1
were recorded on 400 MHz and 100 MHz NMR instrument for H and 13C NMR
1
respectively. All H NMR spectra were reported in units ppm (parts per million), and were
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measured relative to the signals for residual chloroform (7.26 ppm) and DMSO (2.54 ppm) in
the deuterated solvent. All 13C NMR spectra were reported in ppm relative to deuterated
chloroform (77.23 ppm) and DMSO (39.52 ppm). Coupling constants (J) are reported in Hz;
splitting patterns are assigned s = singlet, d = doublet, t = triplet, q = quartet, quin = quintet;
br = broad signal. GC MS and GC analyses were performed with an FID detector; nꢀdecane is
the internal standard. Highꢀresolution mass spectra (HRMS) were performed on TOFꢀQ
analyser.
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General synthetic procedure for C1-(hetero)aryl/PAHs-
β-carboline:
All C1ꢀ(hetero)aryl/PAHsꢀ ꢀcarboline was synthesized by modifying the reported
β
procedure.20 Briefly a mixture of (hetero)aryl/PAHs aldehyde (1.1 mmol) and tryptamine
(1.0 mmol) in anisole (10 ml) was heated to 120 °C over a period of 2h and then 5% Pd/C
(0.5 mmol) was added and reflux at 140 °C for 24h. The reaction mixture was filtered while
in hot and remove the solvent using rotary evaporation gave reddish brown oil, which was
dissolved in 1 ml of DCM and add petroleum ether forming yellow brown precipitate which
is used for direct arylation without doing any further purification. Spectroscopic data of
compounds 1aꢀ1f, 5, and 7 matches well with the literature.20b,21
General synthetic procedure for Cycloruthenated complexes (1cr-8cr):
In an ovenꢀdried, nitrogen gas flushed vial equipped with stirring bar, were placed C1ꢀ
(hetero)aryl/PAHsꢀβꢀcarboline (0.1 mmol), [RuCl2(pꢀcymene)]2 (0.05 mmol, 30.6 mg),
KOAc (0.3 mmol, 29.4 mg) and methanol (3ꢀ5 ml) and the mixture was stirred at ambient
temperature for 12ꢀ20h.22 Yellow precipitate was formed which was filtered and washed with
diethyl ether to get pure solid cycloruthenated complex with good yield (80ꢀ90%).
Synthetic procedure for 10cr:
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In an ovenꢀdried, nitrogen gas flushed vial equipped with stirring bar, were placed 1cr (52
mg, 0.1 mmol), and add 0.5 ml of DMSO solvent and the mixture was stirred at 65 °C for
overnight. The resulting solution was evaporated and the residue purified by column
chromatography using neutral alumina (DCM:MeOH = 95:5). The yellow fraction was
collected and evaporated in vacuum to get 10cr Yield: 95%
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General Synthetic procedure for direct arylation:
In an ovenꢀdried, nitrogen gas flushed vial equipped with stirring bar, were placed C1ꢀ
(hetero)aryl/PAHsꢀβꢀcarboline (0.2 mmol), [RuCl2(pꢀcymene)]2 (5 mol %, 0.01 mmol),
diphenyl aceticacid (30 mol%, 0.06 mmol), anhydrous NMP (1.5 ml). The mixture stirred
for 10 min at room temperature, followed by addition of K2CO3 (0.5mmol) and aryl bromide
(0.5 mmol). The reaction mixture was flushed with nitrogen, sealed with a Teflon–lined cap,
and heated at 120 °C with stirring. After 20h, the reaction mixture was diluted with water and
extracted with ethyl acetate, the organic layer was washed with water and dried over Na2SO4
and solvent was evaporated under reduced pressure. The crude product was purified by
column chromatography using petroleum ether and ethyl acetate as the solvent.
1
Cycloruthenated complex 1cr. Yield: 43.6 mg, 85%; H NMR (400 MHz, DMSOꢀd6): δ
11.75 (s, 1H, NH), 9.28ꢀ9.26 (d, J = 8 Hz, 1H), 8.32ꢀ8.30 (d, J = 8 Hz, 1H), 8.27ꢀ8.26 (br,
2H), 8.02ꢀ8.01 (d, J = 4 Hz, 1H), 7.80ꢀ7.77 (d, J = 9.2 Hz, 1H), 7.61ꢀ7.58 (t, J = 6 Hz, 1H),
7.34ꢀ7.30 (t, J = 8 Hz, 1H), 7.12 (br, 2H), 5.82ꢀ5.80 (d, J = 8 Hz, 1H, pꢀcymene), 5.71ꢀ5.70
(d, J = 4 Hz, 1H, pꢀcymene), 5.48ꢀ5.47 (d, J = 4 Hz, 1H, pꢀcymene), 5.20ꢀ5.19 (d, J = 4 Hz,
1H, pꢀcymene), 2.27 (m, 1H, pꢀcymeneꢀiPrꢀCꢀH), 1.96 (s, 3H, pꢀcymeneꢀCH3), 0.84ꢀ0.82 (d,
J = 8 Hz, 3H, pꢀcymeneꢀiPrꢀCH3), 0.75 ꢀ 0.73 (d, J = 8 Hz, 3H, pꢀcymeneꢀiPrꢀCH3). 13C
NMR (100 MHz, DMSOꢀd6): δ 183.3 (CꢀRu), 149.4, 145.1, 144.1, 141.4, 139.9, 131.0,
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129.6, 128.7, 127.2, 125.2, 121.7, 121.6, 120.2, 120.1, 112.8, 112.7, 101.0, 98.2, 91.3, 89.5,
85.2, 81.9, 30.3, 22.2, 21.3, 18.4. HRMS (ESI) m/z calculated for C27H25ClN2NaRu [M +
Na]+ 537.0647, found 537.0647; m/z calculated for C27H25N2Ru [M ꢀ Cl]+: 479.1061, found
479.1048.
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Cycloruthenated complex 2cr. Yield: 45.9 mg, 87%; H NMR (400 MHz, DMSOꢀd6): δ
11.65 (s, 1H, NH), 9.25ꢀ9.23 (d, J = 8 Hz, 1H), 8.32ꢀ8.31 (d, J = 4 Hz, 1H), 8.29ꢀ8.09 (m,
3H), 7.98ꢀ7.96 (d, J = 8 Hz, 1H), 7.77ꢀ7.75 (d, J = 8 Hz, 1H), 7.61ꢀ7.57 (t, J = 8 Hz, 1H),
7.33ꢀ7.30 (t, J = 8 Hz, 1H), 6.95ꢀ6.93 (d, J = 8 Hz, 1H), 5.82ꢀ5.80 (d, J = 8 Hz, 1H, pꢀ
cymene), 5.69ꢀ5.68 (d, J = 4 Hz, 1H, pꢀcymene), 5.49ꢀ5.47 (d, J = 8 Hz, 1H, pꢀcymene),
5.19ꢀ5.17 (d, J = 8 Hz, 1H, pꢀcymene), 2.42 (s, 3H), 2.29 (m, 1H, pꢀcymꢀiPrꢀCH), 1.97 (s,
3H, pꢀcymeneꢀCH3), 0.83ꢀ0.82 (d, J = 4 Hz, 3H, pꢀcymeneꢀiPrꢀCH3), 0.75ꢀ0.73 (d, J = 8 Hz,
3H, pꢀcymeneꢀiPrꢀCH3). 13C NMR (100 MHz, DMSOꢀd6) δ 183.3 (CꢀRu), 149.6, 145.0,
141.5, 141.3, 140.6, 136.3, 130.7, 129.4, 128.6, 124.9, 122.7, 121.5, 120.1, 112.6, 112.3,
101.0, 97.8, 91.4, 89.3, 85.5, 81.6, 48.6, 30.3, 22.2, 21.4, 18.4. HRMS (ESI) m/z calculated
for C28H27ClN2NaRu [M + Na]+ 551.0804, found 551.0801; m/z calculated for C28H27N2Ru
[M ꢀ Cl]+: 493.1218, found 493.1215.
1
Cycloruthenated complex 3cr. Yield: 48.9 mg, 90%; H NMR (400 MHz, DMSOꢀd6) δ
11.65 (s, 1H, NH), 9.20ꢀ9.18 (d, J = 8 Hz, 1H), 8.29ꢀ8.27 (d, J = 8 Hz, 1H), 8.21ꢀ8.19 (d, J =
8 Hz, 1H), 7.92ꢀ7.91 (d, J = 4 Hz, 1H), 7.79ꢀ7.75 (m, 2H), 7.58ꢀ7.56 (t, J = 4 Hz, 1H), 7.32ꢀ
7.29 (t, J = 6 Hz, 1H), 6.69ꢀ6.67 (d, J = 8 Hz, 1H), 5.79ꢀ5.78 (d, J = 4 Hz, 1H, pꢀcymene),
5.73ꢀ5.72 (d, J = 4 Hz, 1H, pꢀcymene), 5.48ꢀ5.47 (d, J = 4 Hz, 1H, pꢀcymene), 5.21ꢀ5.20 (d, J
= 4 Hz, 1H), 3.91 (s, 3H), 2.3 (m, 1H, pꢀcymeneꢀiPrꢀCH), 1.96 (s, 3H, pꢀcymeneꢀCH3), 0.86ꢀ
0.84 (d, J = 8 Hz, 3H, pꢀcymeneꢀiPrꢀCH3), 0.76ꢀ0.74 (d, J = 8 Hz, 3H, pꢀcymeneꢀiPrꢀCH3).
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13C NMR (100 MHz, DMSOꢀd6): δ 185.6 (CꢀRu), 157.7, 149.4, 145.0, 141.3, 137.2, 130.3,
129.1, 128.5, 126.1, 124.3, 121.5, 120.2, 120.1, 112.6, 111.7, 107.9, 101.0, 98.0, 90.9, 89.7,
85.3, 82.1, 54.8, 30.3, 22.3, 21.2, 18.3. HRMS (ESI) m/z calculated for C28H27ClN2NaORu
[M + Na]+ 567.0743, found 567.0702; m/z calculated for C28H27N2ORu [M ꢀ Cl]+: 509.1167,
found 509.1165.
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Cycloruthenated complex 4cr. Yield: 45.2 mg, 84%; H NMR (400 MHz, DMSOꢀd6): δ
11.92 (s, 1H, NH), 9.34ꢀ9.33 (d, J = 4 Hz, 1H), 8.61 (br, 1H), 8.39ꢀ8.35 (t, J = 8 Hz, 2H),
8.16ꢀ8.15 (d, J = 4 Hz, 1H), 7.79ꢀ7.77 (d, J = 8 Hz, 1H), 7.65ꢀ7.54 (m, 2H), 7.37ꢀ7.35 (d, J =
8 Hz, 1H), 5.93ꢀ5.92 (d, J = 4 Hz, pꢀcymene), 5.85ꢀ5.84 (d, J = 4 Hz, 1H, pꢀcymene), 5.61 ꢀ
5.60 (d, J = 4 Hz, 1H, pꢀcymene), 5.34ꢀ5.33 (d, J = 4 Hz, 1H), 2.2 (m, 1H, pꢀcymeneꢀiPrꢀ
CH), 1.90 (s, 3H, pꢀcymeneꢀCH3), 0.83ꢀ0.81 (d, J = 8 Hz, 3H, pꢀcymeneꢀiPrꢀCH3), 0.75ꢀ0.74
(d, J = 4 Hz, 3H, pꢀcymeneꢀiPrꢀCH3). 13C NMR (100 MHz, DMSOꢀd6): δ 183.4 (CꢀRu),
148.7, 147.2, 145.5, 142.2, 141.7, 131.8, 130.4, 129.2, 125.3, 124.6, 121.8, 120.5, 120.1,
120.0, 114.4, 112.7, 108.9, 102.2, 99.0, 91.8, 89.5, 86.2, 82.2, 30.3, 22.1, 21.4, 18.4. HRMS
(ESI) m/z calculated for C28H24ClN3NaRu [M + Na]+ 562.0600, found 562.0698; m/z
calculated for C28H24N3Ru [M ꢀ Cl]+: 504.1014, found 504.1011.
1
Cycloruthenated complex 5cr. Yield: 43.6 mg, 82%; H NMR (400 MHz, DMSOꢀd6): δ
11.72 (s, 1H, NH), 9.24ꢀ9.23 (d, J = 4 Hz, 1H), 8.32ꢀ8.26 (m, 2H), 8.02ꢀ8.00 (d, J = 8 Hz,
2H), 7.76ꢀ7.74 (d, J = 8 Hz, 1H), 7.61ꢀ7.57 (t, J = 8 Hz, 1H), 7.34ꢀ7.30 (t, J = 8 Hz, 1H),
6.92ꢀ6.88 (t, J = 8 Hz, 1H), 5.85ꢀ5.83 (d, J = 6 Hz, pꢀcymene), 5.76ꢀ5.75 (d, J = 4Hz, 1H, pꢀ
cymene), 5.54ꢀ5.52 (d, J = 8 Hz, 1H, pꢀcymene), 5.26ꢀ5.25 (d, J = 4 Hz, 1H), 2.3 (m, 1H, pꢀ
cymeneꢀiPrꢀCH), 1.97 (s, 3H, pꢀcymeneꢀCH3), 0.84ꢀ0.82 (d, J = 8 Hz, 3H, pꢀcymeneꢀiPrꢀ
CH3), 0.76ꢀ0.74 (d, J = 8 Hz, 3H, pꢀcymeneꢀiPrꢀCH3). 13C NMR (100 MHz, DMSOꢀd6): δ
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187.1 (CꢀRu), 159.1, 148.4, 145.1, 141.5, 140.6, 130.7, 129.7, 128.8, 126.4, 126.3, 125.4,
125.2, 121.6, 120.3, 120.1, 112.8, 112.6, 108.6, 108.4, 101.6, 98.6, 91.4, 89.5, 85.8, 82.2,
30.7, 22.1, 21.3, 18.3. HRMS (ESI) m/z calculated for C27H24ClFN2NaRu [M + Na]+
555.0553, found 555.0551; m/z calculated for C27H24FN2Ru [M ꢀ Cl]+ 497.0967, found
497.0964.
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Cycloruthenated complex 6cr. Yield: 44.7 mg, 80%; H NMR (400 MHz, DMSOꢀd6):δ
11.97 (s,1H, NH), 9.37ꢀ9.35 (d, J = 8 Hz, 1H), 8.96ꢀ8.95 (d, J = 4 Hz,1H), 8.45ꢀ8.43 (d, J = 8
Hz, 1H), 8.38ꢀ8.36 (d, J = 8 Hz, 1H), 8.20ꢀ8.19 (d, J = 4 Hz, 1H), 7.95ꢀ7.92 (m,1H), 7.80ꢀ
7.78 (d, J = 8 Hz, 1H), 7.67ꢀ7.63 (t, J = 8 Hz, 1H), 7.39ꢀ7.35 (t, J = 8 Hz,1H), 5.93ꢀ5.92 (d, J
= 4 Hz, 1H, pꢀcymene), 5.86ꢀ5.84 (d, J = 8 Hz, 1H, pꢀcymene), 5.63ꢀ5.62 (d, J = 4 Hz,1H, pꢀ
cymene), 5.37ꢀ5.35 (d, J = 8 Hz, 1H, pꢀcymene), 2.33 (m, 1H, pꢀcymeneꢀiPrꢀCH), 2.01 (s,
3H, pꢀcymeneꢀCH3), 0.85ꢀ0.83 (d, J = 8 Hz, 3H, pꢀcymeneꢀiPrꢀCH3), 0.76ꢀ0.74 (d, J = 8 Hz,
3H, pꢀcymeneꢀiPrꢀCH3). 13C NMR (100 MHz, DMSOꢀ d6):δ 184.7 (CꢀRu), 150.7, 145.6,
144.9, 132.6, 130.6, 129.3, 124.7, 121.8, 120.6, 120.0, 117.0, 114.8, 112.7, 102.4, 99.4, 91.4,
90.0, 86.2, 82.5, 78.9, 30.4, 22.2, 21.2, 18.4.
HRMS (ESI) m/z calculated for
C27H24ClN3NaO2Ru [M + Na]+ 582.0498, found 582.0496; m/z calculated for C27H24N3O2Ru
[M ꢀ Cl]+ 524.0912, found 524.0909.
1
Cycloruthenated complex 7cr. Yield: 42.1 mg, 81%; H NMR (400 MHz, DMSOꢀd6): δ
11.24 (s, 1H, NH), 9.11ꢀ9.10 (d, J = 4 Hz, 1H), 8.27ꢀ8.25 (d, J = 8 Hz, 1H), 7.85ꢀ7.81 (br,
4H), 7.58ꢀ7.54 (t, J = 8 Hz, 1H), 7.32ꢀ7.28 (t, J = 8 Hz, 1H), 5.86ꢀ5.85 (d, J = 4 Hz, 2H, pꢀ
cymene), 5.55ꢀ5.54 (d, J = 4 Hz, 1H, pꢀcymene), 5.32ꢀ5.30 (d, J = 8 Hz, 1H, pꢀcymene), 2.35
(m, 1H, pꢀcymeneꢀiPrꢀCH), 1.97 (s, 3H, pꢀcymeneꢀCH3), 0.88ꢀ0.87 (d, J = 4 Hz, 3H, pꢀ
i
cymeneꢀ PrꢀCH3), 0.78ꢀ0.76 (d, J = 8 Hz, 3H, pꢀcymeneꢀ iPrꢀCH3). 13C NMR (100 MHz,
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DMSOꢀd6): δ 183.8 (CꢀRu), 145.9, 144.8, 141.4, 137.2, 132.2, 128.9, 128.6, 128.4, 127.3,
121.6, 120.7, 120.1, 115.6, 113.1, 110.5, 100.6, 99.0, 89.7, 87.6, 85.5, 81.0, 30.4, 22.3, 21.4,
18.4. HRMS (ESI) m/z calculated for C25H23ClN2NaRuS [M + Na]+ 543.0212, found
543.0211; m/z calculated for C25H23N2RuS [M ꢀ Cl]+ 485.0625, found 485.0620.
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Cycloruthenated complex 8cr. Yield: 45.1 mg, 80%; H NMR (400 MHz, DMSOꢀd6): δ
11.94 (s,1H, NH), 9.37ꢀ9.36 (d, J = 4 Hz, 1H), 8.80 (s, 1H), 8.63 (s, 1H), 8.38ꢀ8.36 (d, J = 8
Hz, 1H), 8.13ꢀ8.12 (d, J = 4 Hz, 1H), 8.05ꢀ8.03 (d, J = 8 Hz, 1H), 7.86ꢀ7.80 (dd, J = 8.2 Hz,
2H), 7.68ꢀ 7.64 (t, J = 8 Hz, 1H), 7.51ꢀ7.48 (t, J = 6 Hz, 1H), 7.39 (q, J = 8 Hz, 2H), 5.90 ꢀ
5.89 (d, J = 4 Hz, 1H, pꢀcymene), 5.80ꢀ5.78 (d, J = 8 Hz, 1H pꢀcymene), 5.51 ꢀ5.49 (d, J = 8
Hz, 1H pꢀcymene), 5.24ꢀ5.23 (d, J = 4 Hz, 1H), 2.30 (m, 1H, pꢀcymeneꢀ iPrꢀCH), 2.02 (s, 3H,
pꢀcymeneꢀCH3), 0.85ꢀ0.83 (d, J = 8 Hz, 3H, pꢀcymeneꢀ iPrꢀCH3), 0.73ꢀ0.71 (d, J = 8 Hz, 3H,
pꢀcymeneꢀ iPrꢀCH3). 13C NMR (100 MHz, DMSOꢀd6): δ 176.5 (CꢀRu), 148.5, 145.5, 144.6,
141.6, 136.3, 133.3, 131.3, 130.3, 129.0, 128.3, 126.2, 125.5, 123.7, 123.1, 121.8, 120.4,
120.2, 113.7, 112.6, 101.6, 98.1, 91.7, 89.9, 85.0, 81.5, 48.6, 30.3, 22.2, 21.3, 18.4. HRMS
(ESI) m/z calculated for C31H27ClN2NaRu [M + Na]+ 587.0804, found 587.0800; m/z
calculated for C31H27N2Ru [M ꢀ Cl]+ 529.1218, found 529.1215.
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Cycloruthenated complex 10cr. Yield: 55.9 mg, 95%; H NMR (400MHz,DMSOꢀd6): δ
11.82 (s, 1H, NH), 9.56ꢀ9.55 (d, J = 4 Hz, 1H), 8.37ꢀ8.28 (m, 2H), 8.15ꢀ8.14 (d, J = 4 Hz,
1H), 7.81ꢀ7.79 (d, J = 8 Hz, 1H), 7.65ꢀ7.61 (t, J = 8 Hz,1H), 7.35ꢀ731 (t, J = 8 Hz,1H), 7.24
(br, singlet, 2H), 2.51 (s, 6H). 13C NMR (100MHz, DMSOꢀd6): δ 177.3 (CꢀRu), 149.5,
146.9, 141.9, 141.6, 140.5, 131.0, 130.7, 129.1, 127.6, 125.9, 121.9, 121.7, 120.3, 120.1,
112.8, 112.7, 47.6. HRMS (ESI) m/z calculated for C25H35N2NaO4S4Ru [M + Na]+
680.0421 found 680.0429.
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1-([1,1’:3’,1’’-terphenyl]-2'-yl)-9H-pyrido[3,4-b]indole 3aa. White solid, Yield: 67.3 mg,
7
8
9
1
85%; Rf (PE/EA = 20/1): 0.7. H NMR (400 MHz, CDCl3): δ 8.15 (d, J = 5.2 Hz, 1H), 7.92
(d, J = 7.9 Hz, 1H), 7.60ꢀ7.55 (m, 3H), 7.50 (d, J = 8.2 Hz, 2H), 7.38 (t, J = 7.6 Hz, 1H), 7.21
(d, J = 8 Hz, 1H), 7.14 (t, J = 7.4 Hz, 1H), 7.02ꢀ7.00 (m, 4H), 6.93ꢀ6.92 (m, 6H). 13C NMR
(100 MHz, CDCl3): δ 142.7, 142.2, 140.9, 140.0, 138.7, 136.9, 135.1, 129.8, 129.1, 128.9,
128.0, 127.7, 126.7, 121.7, 121.6, 119.8, 116.5, 113.3, 111.2. HRMS [M + H]+ calculated for
C29H20N2: 397.1705, found: 397.1697.
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1-([1,1'-biphenyl]-2-yl)-9H-pyrido [3,4-b]indole 4aa. White solid, Yield: 5.1 mg, 8%; Rf
1
(PE/EA = 20/1): 0.7. H NMR (400 MHz, CDCl3): δ 8.45 (d, J = 5.3 Hz, 1H), 7.98 (d, J =
8.0 Hz, 1H), 7.80 (d, J = 5.3 Hz, 1H), 7.68 (d, J = 7.0, 1.6 Hz, 1H), 7.68ꢀ7.47 (m, 4H), 7.37
(t, J = 8 Hz, 1H), 7.16ꢀ7.12 (m, 4H), 7.03ꢀ6.96 (m, 3H). 13C NMR (100 MHz, CDCl3): δ
140.8, 140.5, 140.1, 139.4, 135.5, 133.7, 131.4, 130.4, 129.2, 128.9, 128.6, 128.3, 128.2,
128.0, 127.7, 127.2, 121.6, 119.9, 113.7, 111.1. HRMS [M + H]+ calculated for C23H16N2:
321.1392, found: 321.1394.
1-(4,4''-di-tert-butyl-[1,1':3',1''-terphenyl]-2'-yl)-9
H
-pyrido[3,4-
b
]indole 3ab.
White
solid, Yield: 92.5 mg, 91%; Rf (PE/EA = 20/1): 0.65. 1H NMR (400 MHz, CDCl3): δ 8.16
(d, J = 5.6 Hz, 1H), 7.91 (d, J = 8 Hz, 1H), 7.61 (d, J = 5.2 Hz, 1H), 7.56ꢀ7.46 (m, 4H), 7.35
(t, J = 7.4 Hz, 1H), 7.17 (d, J = 8.4 Hz, 1H), 7.12 (t, J = 7.4 Hz, 1H), 6.92 (s, 8H), 1.01 (s,
18H). 13C NMR (100 MHz, CDCl3): δ 149.5, 143.5, 142.6, 140.1, 138.6, 138.0, 135.3,
134.9, 129.5, 129.0, 128.6, 128.1, 127.8, 124.5, 121.6, 121.5, 119.6, 113.1, 111.0, 34.2, 31.1.
HRMS [M + H]+ calculated for C37H36N2: 509.2957, found: 509.2955.
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1-(2,6-di(naphthalen-2-yl)phenyl)-9H-pyrido[3,4-b]indole 3ac. White solid, Yield: 89.3
1
mg, 90%; Rf (PE/EA = 20/1): 0.71. H NMR (400 MHz, CDCl3): δ 8.12 (d, J = 5.2 Hz, 1H),
7.83 (d, J = 8 Hz, 2H), 7.70 (s, 1H), 7.67 (br, 2H), 7.64ꢀ7.61 (m, 3H), 7.50ꢀ7.51 (m, 5H), 7.35
(d, J = 8.4 Hz, 2H), 7.29ꢀ7.24 (m, 5H), 7.17 (d, J = 8.2 Hz, 1H), 7.07ꢀ7.03 (m, 3H). 13C
NMR (100 MHz, CDCl3): δ 142.7, 139.9, 138.8, 138.4, 135.1, 133.0, 130.2, 129.2, 128.3,
128.0, 127.9, 127.4, 127.1, 127.0, 125.9, 125.7, 121.7, 121.6, 119.8, 113.4, 111.2. HRMS
[M + H]+ calculated for C37H24N2: 497.2018, found: 497.2020.
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1,1'-(2'-(9
H
-pyrido[3,4-
b
]indol-1-yl)-[1,1':3,1''-terphenyl]-4,4''-diyl)diethanone
3ad.
1
White solid, Yield: 79.7 mg, 83%; Rf (PE/EA = 20/1): 0.35. H NMR (400 MHz, CDCl3): δ
8.17 (d, J = 5.6 Hz, 1H), 7.94 (d, J = 8 Hz, 1H), 7.64ꢀ7.61 (m, 3H), 7.55ꢀ7.51 (m, 6H), 7.40
(t, J = 8 Hz, 1H), 7.24 (d, J = 8 Hz, 1H), 7.17 (d, J = 8 Hz, 1H), 7.12 (m, 4H), 2.36 (s, 6H).
13C NMR (100 MHz, CDCl3): δ 197.6, 145.5, 141.8, 140.0, 138.9, 135.3, 135.0, 131.0,
130.2, 129.4, 129.1, 128.4, 127.8, 121.8, 121.6, 120.2, 113.9, 111.3, 26.5. HRMS [M + H]+
calculated for C33H24N2O2: 481.1916, found: 481.1915.
1-(2'-(9H
-pyrido[3,4-
b
]indol-1-yl)-[1,1'-biphenyl]-4-yl)ethanone 4ad. White solid, Yield:
1
7.2 mg, 10%; Rf (PE/EA = 20/1): 0.4. H NMR (400 MHz, CDCl3): δ 8.39 (d, J = 5.2 Hz,
1H), 8.01 (d, J = 8 Hz, 1H), 7.80 (d, J = 5.2 Hz, 1H), 7.75 (s, 1H), 7.66 (d, J = 6.8 Hz, 1H),
7.60 (d, J = 8 Hz, 1H), 7.51 (m, 3H), 7.40 (t, J = 7.6 Hz, 1H), 7.21ꢀ7.14 (m, 4H), 2.35 (s, 3H).
13C NMR (100 MHz, CDCl3): δ 197.6, 145.6, 143.4, 140.0, 139.8, 139.4, 136.8, 135.4,
133.9, 131.0, 130.5, 129.3, 129.0, 128.9, 128.7, 128.4, 128.2, 121.7, 121.6, 120.1, 113.8,
111.2, 26.5. HRMS [M + H]+ calculated for C25H18N2O: 363.1497, found: 363.1453.
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1-(4,4''-dimethoxy-[1,1':3',1''-terphenyl]-2'-yl)-9H-pyrido[3,4-b]indole 3ae. White solid,
1
Yield: 77.5 mg, 85%; Rf (PE/EA = 20/1): 0.37. H NMR (400 MHz, CDCl3): δ 8.30 (d, J =
4 Hz, 1H), 8.02 (d, J = 8 Hz, 1H), 7.77 (s, 1H), 7.72 (d, J = 4 Hz, 1H), 7.53 (d, J = 8 Hz, 2H),
7.48ꢀ7.44 (t, J = 8 Hz, 1H), 7.31ꢀ7.17 (m, 2H), 7.03 (d, J = 8 Hz, 4H), 6.57 (d, J = 8 Hz, 4H),
3.63 (s, 6H). 13C NMR (100 MHz, CDCl3): δ 158.2, 143.5, 142.3, 140.1, 138.7, 136.6, 135.1,
134.5, 133.4, 131.4, 130.0, 129.4, 129.0, 128.0, 121.7, 121.7, 119.8, 113.3, 113.2, 111.3,
55.0. HRMS [M + H]+ calculated for C31H24N2O2: 457.1916, found: 457.1918.
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1-(4'-methoxy-[1,1'-biphenyl]-2-yl)-9
H
-pyrido[3,4-
b
]indole 4ae.
1
White solid, Yield: 7.0 mg, 10%; Rf (PE/EA = 20/1): 0.41. H NMR (400 MHz, CDCl3): δ
8.54 (d, J = 5.6 Hz, 1H), 8.10 (d, J = 8 Hz, 1H), 8.04 (s, 1H), 8.00 (d, J = 5.2 Hz, 1H), 7.75
(d, J = 7.6 Hz, 1H ), 7.58 (d, J = 3.6 Hz, 2H), 7.53 (m, 2H), 7.29ꢀ7.26 (m, 1H), 7.16 (d, J = 8
Hz, 2H), 6.63 (d, J = 8.4 Hz, 2H), 3.61 (s, 3H). 13C NMR (100 MHz, CDCl3): δ 159.0,
140.6, 133.3, 132.5, 131.6, 130.6, 130.3, 129.8, 127.9, 122.1, 120.7, 114.2, 114.0, 111.6,
55.1. HRMS [M + H]+ calculated for C24H18N2O: 351.1497, found: 351.1460.
N4 N4 N4'' N4''-tetramethyl-2'-(9H-pyrido[3,4-b]indol-1-yl)-[1,1':3',1''-terphenyl]-4,4''-
, , ,
diamine 3af. White solid, Yield: 78.1 mg, 81%; Rf (PE/EA = 20/1): 0.3. 1H NMR (400
MHz, CDCl3): δ 8.22 (d, J = 5.6 Hz, 1H), 7.94 (d, J = 8 Hz, 1H), 7.65 (s, 1H), 7.61 (d, J = 4
Hz, 1H), 7.49ꢀ7.45 (m, 1H), 7.39–7.32 (m, 3H), 7.21 (d, J = 8 Hz, 1H), 7.13 (t, J = 5.8 Hz,
1H), 6.86 (d, J = 8 Hz, 4H), 6.29 (d, J = 8 Hz, 4H), 2.68 (s, 12H). 13C NMR (100 MHz,
CDCl3): δ 149.0, 144.3, 142.7, 140.2, 138.8, 135.3, 134.2, 129.6, 129.3, 129.2, 128.9, 128.8,
128.0, 127.7, 121.9, 121.9, 121.6, 119.5, 113.0, 111.8, 111.4, 40.3. HRMS [M + H]+
calculated for C33H30N4: 483.2549, found: 483.2546.
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2'-(9
H
-pyrido[3,4-
b
]indol-1-yl)-[1,1’:3’,1’’-terphenyl]-4,4’’-dicarbonitrile 3ag.
White
1
solid, Yield: 75.8 mg, 85%; Rf (PE/EA = 20/2): 0.63. H NMR (400 MHz, CDCl3): δ 8.35
(d, J = 4 Hz, 1H), 8.04 (d, J = 8 Hz, 1H), 7.82 (d, J = 8.0 Hz, 1H), 7.75 (s, 1H), 7.69ꢀ7.67 (m,
1H), 7.67ꢀ7.41 (m, 4H), 7.45 (t, J = 6 Hz, 1H). 7.30ꢀ7.19 (m, 8H). 13C NMR (100 MHz,
CDCl3): δ 142.7, 142.2, 140.9, 140.0, 138.7, 136.9, 135.1, 129.8, 129.1, 128.9, 128.1, 127.7,
126.7, 121.7, 121, 6, 119.8, 116.5, 113.3, 111.2. HRMS [M + H]+ calculated for C31H18N4:
447.1610, found: 447.1612.
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2'-(9
H
-pyrido[3,4-
b
]indol-1-yl)-[1,1'-biphenyl]-4-carbonitrile 4ag. White solid, Yield: 6.2
1
mg, 9%; Rf (PE/EA = 20/2): 0.66. H NMR (400 MHz, CDCl3): δ 8.35 (d, J = 4 Hz, 1H),
8.04 (d, J = 8 Hz, 1H), 7.82 (d, J = 8.0 Hz, 1H), 7.75(s, 1H), 7.69ꢀ7.67 (m, 1H), 7.67ꢀ7.41 (m,
4H), 7.45(t, J = 6 Hz, 1H). 7.30ꢀ7.19(m, 8H). 13C NMR (100 MHz, CDCl3): δ 145.5, 140.0,
139.3, 133.9, 131.8, 130.8, 130.6, 129.5, 129.2, 129.0, 128.7, 121.9, 121.6, 120.4, 118.7,
114.0, 111.2, 110.7. HRMS [M + H]+ calculated for C24H15N3: 346.1344, found: 346.1299.
1-(3,3'',5,5''-tetramethoxy-[1,1':3',1''-terphenyl]-2'-yl)-9H-pyrido[3,4-b]indole
3an.
1
White solid, Yield: 90.8 mg, 88%; Rf (PE/EA = 20/2): 0.57. H NMR (400 MHz, CDCl3): δ
8.23 (d, J = 4 Hz, 1H), 7.93 (d, J = 8 Hz, 1H), 7.81 (s, 1H), 7.66 (d, J = 8Hz, 1H), 7.53ꢀ7.48
(m, 2H), 7.37ꢀ7.33 (t, J = 8Hz, 1H), 7.22ꢀ7.18 (t, J = 8Hz, 2H), 7.15ꢀ7.11(t, J = 8Hz, 1H),
6.21 (d, J = 3Hz, 4H), 6.03 (s, 2H), 3.30 (s,12H). 13C NMR (100 MHz, CDCl3): δ 159.9,
143.5, 142.7, 142.6, 140.1, 138.5, 135.4, 134.4, 131.4, 130.0, 129.6, 129.2, 128.2, 121.7,
121.5, 120.0, 111.2, 107.1, 106.9, 99.8, 55.2, 55.0. HRMS [M + H]+ calculated for
C33H28N2O4: 517.2127, found: 517.2124.
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1-(2,6-di(thiophen-2-yl)phenyl)-9H-pyrido[3,4-b]indole 3ah. Beige solid, Yield: 62.0 mg,
1
76%; Rf (PE/EA = 20/2): 0.64. H NMR (400 MHz, CDCl3): δ 8.40 (d, J = 4 Hz, 1H), 7.99
(d, J = 8 Hz, 1H), 7.82 (d, J = 8 Hz, 1H), 7.77 (s, 1H), 7.61ꢀ7.59 (d, J = 12 Hz, 2H), 7.51ꢀ
7.49 (m, 1H), 7.38ꢀ7.34 (m, 1H), 7.17ꢀ7.12 (m, 3H), 6.90ꢀ6.88 (dd, J = 4 Hz, 2H), 6.65ꢀ6.53
(m, 4H). 13C NMR (100 MHz, CDCl3): δ 142.2, 141.7, 140.1, 138.8, 135.6, 135.5, 133.8,
130.0, 129.3, 128.8, 128.3, 128.2, 127.4, 127.0, 126.8, 126.0, 126.0, 121.8, 121.7, 121.6,
120.0, 114.5, 111.5. HRMS [M + H]+ calculated for C25H16N2S2: 409.0833, found:
409.0830.
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1-(2-(thiophen-2-yl)phenyl)-9H-pyrido[3,4-b]indole 4ah. Beige solid, Yield: 11.7 mg,
18%; Rf (PE/EA = 20/2): 0.70. 1H NMR (400 MHz, CDCl3): δ 8.49 (d, J = 5.2 Hz, 1H),
8.02 (d, J = 7.6 Hz, 1H), 7.87 (d, J = 5.2 Hz, 1H), 7.73 (s, 1H), 7.64ꢀ7.58 (m, 2H), 7.49ꢀ7.36
(m, 3H), 7.21ꢀ7.17 (m, 3H), 6.96 (d, J = 3.2 Hz, 1H), 6.62 (d, J = 4.8 Hz, 1H). 13C NMR
(100 MHz, CDCl3): δ 143.6, 141.9, 140.2, 139.3, 136.5, 134.2, 133.3, 131.4, 130.2, 129.2,
128.8, 128.3, 128.2, 127.4, 126.6, 126.0, 121.7, 121.5, 120.0, 114.0, 111.3. HRMS [M + H]+
calculated for C21H14N2S: 327.0956, found: 327.0903.
1-(2,6-di(pyridin-3-yl)phenyl)-9H-pyrido[3,4-b]indole 3ai. Beige solid, Yield: 67.6 mg,
85%; Rf (PE/EA = 20/20): 0.45. 1H NMR (400 MHz, DMSOꢀd6): δ 11.17 (s, 1H), 8.25 (s,
2H), 8.17ꢀ8.14 (m, 3H), 8.08 (d, J = 8 Hz, 1H), 7.87 (d, J = 4 Hz, 1H), 7.82ꢀ7.79 (t, J = 6 Hz,
1H), 7.67 (d, J = 8 Hz, 2H), 7.45ꢀ7.41 (t, J = 8 Hz, 4H), 7.16ꢀ7.13 (t, J = 6 Hz, 1H), 7.06ꢀ7.03
(m, 2H). 13C NMR (100 MHz, DMSOꢀd6): δ 148.9, 147.6, 141.9, 140.6, 139.0, 137.3,
136.1, 135.8, 135.0, 130.0, 129.2, 127.9, 127.2, 122.5, 121.6, 120.3, 119.1, 113.8, 111.9.
HRMS [M + H]+ calculated for C27H18N4: 399.1610, found: 399.1607.
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1-(2-(pyridin-3-yl)phenyl)-9H-pyrido[3,4-b]indole 4ai. Beige solid, Yield: 5.7 mg, 9%; Rf
1
(PE/EA = 20/10): 0.55. H NMR (400 MHz, DMSOꢀd6): δ 11.10 (s, 1H), 8.30 (d, J = 8 Hz,
7
8
9
1H), 8.2 (s, 1H), 8.20ꢀ8.17 (m, 2H), 8.04 (d, J = 4 Hz, 1H), 7.70ꢀ7.64 (m, 4H), 7.48ꢀ7.43 (m,
3H), 7.21ꢀ7.18 (t, J = 6 Hz, 1H), 7.10ꢀ7.07 (m, 1H). 13C NMR (100 MHz, DMSOꢀd6): δ
149.0, 147.5, 143.2, 140.8, 137.7, 137.6, 137.1, 136.1, 135.8, 133.8, 130.6, 130.4, 129.0,
128.2, 128.0, 128.0, 122.7, 121.6, 120.5, 119.2, 113.8, 112.0. HRMS [M + H]+ calculated
for C22H15N3: 322.1344, found: 322.1342.
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1-(2,6-di(quinolin-6-yl)phenyl)-9H-pyrido[3,4-b]indole 3aj. White solid, Yield: 74.7 mg,
1
75%; Rf (PE/EA = 20/20): 0.44. H NMR (400 MHz, DMSOꢀd6): δ 11.19 (s, 1H), 8.74 (, J =
4 Hz, 1H), 8.10 (s, 1H), 8.09 (d, J = 4 Hz, 2H), 7.98ꢀ7.74 (m, 8H), 7.58 (d, J = 8Hz, 2H),
7.41ꢀ7.36 (m, 6H), 7.08ꢀ7.05 (m, 1H). 13C NMR (100 MHz, DMSOꢀd6): δ 150.3, 146.2,
141.6, 140.5, 139.0, 135.8, 135.1, 130.5, 130.0, 129.0, 127.9, 127.8, 127.5, 127.1, 121.5,
120.2, 119.0, 113.6, 111.8. HRMS [M + H]+ calculated for C35H22N4: 499.1923, found:
499.1926.
1-(2-(quinolin-6-yl)phenyl)-9Hꢀpyrido[3,4-b]indole 4aj. White solid, Yield: 14.1 mg,
19%; Rf (PE/EA = 20/10): 0.60. 1H NMR (400 MHz, CDCl3): δ 8.66 (dd, J = 4.2 Hz, 1H),
8.35 (d, J = 5.3 Hz, 1H), 8.03 (s, 1 H), 7.95 (d, J = 8 Hz, 1H), 7.85 (dd, J = 8 Hz, 1H), 7.76
(d, J = 5.2 Hz, 1H), 7.66 (dd, J = 7.6 Hz, 2H), 7.65 (s, 2H), 7.63ꢀ7.60 (m, 1H), 7.58ꢀ7.36 (m,
2H), 7.35ꢀ7.20 (m, 2H),7.29ꢀ7.03 (m, 3H). 13C NMR (100 MHz, CDCl3): δ 150.3, 147.1,
143.6, 140.1, 140.0, 139.3, 139.1, 136.9, 136.0, 134.0, 130.9, 130.6, 129.3, 129.0, 128.0,
127.5, 121.7, 121.5, 121.2, 120.0, 113.8, 111.2. HRMS [M + H]+ calculated for C26H17N3:
372.1501, found: 372.1488.
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1-(2,6-di(quinolin-3-yl)phenyl)-9
H
-pyrido[3,4-b]indol 3ak. White solid, Yield: 77.7 mg,
1
78%; Rf (PE/EA = 20/20): 0.52. H NMR (400 MHz, DMSOꢀd6): δ 11.30 (s, 1H), 8.50 (s,
2H), 8.19ꢀ8.10 (br, 3H), 8.00 (br, 1H), 8.01 (d, J = 5.3 Hz, 1H), 8.00ꢀ7.87 (m, 7H), 7.63 (m,
2H), 7.51 (m, 2H), 7.41 (s, 2H), 7.11 (br, 1H). 13C NMR (100 MHz, DMSOꢀd6): δ 155.5,
151.1, 147.1, 145.9, 144.2, 142.7, 141.3, 140.4, 140.3, 138.9, 135.9, 134.6, 133.6, 133.2,
132.6, 132.0, 132.0, 126.9, 125.5, 124.4, 119.2, 117.1. HRMS [M + H]+ calculated for
C35H22N4: 499.1844, found: 499.1848.
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1-(2-(quinolin-3-yl)phenyl)-9H-pyrido[3,4-b]indole 4ak. White solid, Yield: 7.4 mg, 10%;
1
Rf (PE/EA = 20/10): 0.65. H NMR (400 MHz, DMSOꢀd6): δ 11.20 (s, 1H), 8.43 (d, J = 2.2
Hz, 1H), 8.23 (d, J = 5.2 Hz, 1H), 8.21ꢀ8.05 (m, 2H), 8.01 (d, J = 5.3 Hz, 1H), 7.79ꢀ7.69 (m,
5H), 7.64 (s, 1H), 7.62 (d, J = 8 Hz, 1H), 7.51ꢀ7.48 (m, 1H), 7.44 (br, 2H), 7.19ꢀ7.15 (m,
1H). 13C NMR (100 MHz, DMSOꢀd6): δ 150.6, 145.8, 143.2, 140.8, 137.8, 137.5, 137.3,
134.7, 134.0, 133.8, 130.9, 130.6, 129.3, 129.1, 128.3, 128.0, 127.1, 126.6, 121.6, 120.5,
119.2, 113.8, 112.0. HRMS [M + H]+ calculated for C26H17N3: 372.1501 found: 372.1481.
1-(2,6-di(1
H
-indol-5-yl)phenyl)-9H-pyrido[3,4-b]indole 3al. White solid, Yield: 75.8 mg,
1
80%; Rf (PE/EA = 20/20): 0.35. H NMR (400 MHz, DMSOꢀd6): δ 10.93 (s, 1H), 10.86 (s,
2H), 8.11 (d, J = 4 Hz, 1H), 8.01 (d, J = 8 Hz, 1H), 7.72 (d, J = 4 Hz, 2H), 7.69ꢀ7.65 (m, 2H),
7.40ꢀ7.36 (m, 4H), 7.17 (t, J = 3 Hz, 2H), 7.09 (m, 1H), 6.96 (d, J = 8.4 Hz, 2H), 6.80 (dd, J
= 8.4 Hz, 2H), 6.20 (s, 2H). 13C NMR (100 MHz, DMSOꢀd6): δ 144.5, 143.6, 140.4, 136.8,
135.4, 135.2, 134.3, 132.1, 129.2, 128.0, 127.3, 126.9, 126.4, 125.2, 122.4, 121.3, 120.5,
120.4, 118.6, 112.9, 111.9, 109.9, 101.0. HRMS [M + H]+ calculated for C33H22N4:
475.1923, found: 475.1925.
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1-(2-(1H-indol-5-yl)phenyl)-9H-pyrido[3,4-b]indole 4al. White solid, Yield: 9.3 mg, 13%;
1
Rf (PE/EA = 20/10): 0.4. H NMR (400 MHz, CDCl3): δ 8.58 (d, J = 5.2 Hz, 1H), 8.02 (d, J
= 7.6 Hz, 2H), 7.87 (d, J = 5.2 Hz, 1H), 7.82ꢀ7.67 (m, 3H), 7.61 (s, 2H), 7.65ꢀ7.50 (m, 2H),
7.35 (t, J = 7.7 Hz, 1H), 7.21ꢀ6.96 (m, 4H), 6.46 (s, 1H). 13C NMR (100 MHz, CDCl3): δ
141.5, 140.1, 139.4, 133.8, 132.8, 131.6, 130.8, 129.0, 128.6, 128.1, 127.9, 127.2, 124.7,
123.2, 121.4, 121.4, 120.5, 119.6, 113.5, 111.0, 110.9, 102.8. HRMS [M + H]+ calculated
for C25H17N3: 360.1501, found: 360.1457.
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1-(2,6-di(9
H
-carbazol-3-yl)phenyl)-9
H
-pyrido[3,4-b]indole 3am.
1
White solid, Yield: 90.7 mg, 79%; Rf (PE/EA = 20/20): 0.45. H NMR (400 MHz, DMSOꢀ
d6): δ 11.07 (s, 1H), 11.03 (s, 2H), 8.10 (d, J = 4 Hz, 1H), 7.94ꢀ7.91 (m, 3H), 7.75 (d, J = 8
Hz, 3H), 7.67 (d, J = 4 Hz, 1H), 7.64 (d, J = 8 Hz, 2H), 7.41ꢀ7.27 (m, 6H), 7.12ꢀ7.03 (m,
7H). 13C NMR (100 MHz, DMSOꢀd6): δ 144.3, 143.1, 140.4, 139.8, 138.1, 136.8, 135.7,
135.4, 131.6, 129.2, 128.3, 127.4, 126.6, 126.5, 125.3, 122.2, 121.6, 121.4, 120.5, 119.5,
118.7, 118.1, 118.8, 110.9, 109.6. HRMS [M + H]+ calculated for C41H26N4: 575.2236,
found: 575.2235.
1-(2-(9
H
-carbazol-3-yl)phenyl)-9H-pyrido[3,4-b]indole 4am. White solid, Yield: 14.7 mg,
1
18%; Rf (PE/EA = 20/10): 0.5. H NMR (400 MHz, CDCl3): δ 8.46 (d, J = 5.2 Hz, 1H), 8.05
(s, 1H), 7.97 (s, 1H), 7.89 (d, J = 8 Hz, 1H), 7.81 (d, J = 7.6 Hz, 1H), 7.76 (d, J = 5.2 Hz, 1H)
7.68ꢀ7.61 (m, 3H), 7.53 (t, J = 7.6 Hz, 1H), 7.43 (t, J = 7.5 Hz, 1H), 7.24ꢀ7.15 (m, 3H), 7.09
(m, 3H), 6.97 (d, J = 8.2 Hz, 1H), 6.85 (d, J = 8.4 Hz, 1H). 13C NMR (100 MHz, CDCl3): δ
144.5, 141.3, 140.0, 139.8, 139.3, 138.6, 136.9, 133.8, 132.1, 131.5, 130.9, 129.2, 128.8,
128.0, 127.4, 126.7, 125.8, 123.5, 123.1, 121.5, 121.4, 120.2, 120.2, 119.7, 119.4, 113.6,
111.1, 110.6, 110.4. HRMS [M + H]+ calculated for C29H19N3: 410.1657, found: 410.1640.
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1-(5-methyl-[1,1'-biphenyl]-2-yl)-9
H
-pyrido[3,4-b]indole 3ba. White solid, Yield: 72.1
7
8
9
mg, 88%; Rf (PE/EA = 20/1): 0.75. 1H NMR (400 MHz, CDCl3): δ 8.44 (d, J = 5.2 Hz,
1H), 7.97 (d, J = 8.0 Hz, 1H), 7.78 (d, J = 5.2 Hz, 1H), 8.44 (d, J = 7.7 Hz, 1H), 7.51 (s, 1H),
7.36ꢀ7.34 (m, 3H), 7.31 (d, J = 2.6 Hz, 1H), 7.17ꢀ7.11 (m, 5H), 7.01ꢀ6.92 (m, 5H), 2.44 (s,
3H). 13C NMR (100 MHz, CDCl3): δ 140.9, 140.4, 140.1, 139.2, 139.1, 133.8, 131.3, 131.1,
128.8, 128.5, 128.3, 128.2, 127.2, 121.6, 121.4, 119.9, 113.5, 111.0, 21.4. HRMS [M + H]+
calculated for C30H22N2: 411.1861, found: 411.1863.
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1-(5-methyl-[1,1'-biphenyl]-2-yl)-9H-pyrido[3,4-b]indole 4ba.
White solid, Yield: 5.3 mg, 8%; Rf (PE/EA = 20/1): 0.8. 1H NMR (400 MHz, CDCl3): δ
8.43 (d, J = 5.3 Hz, 1H), 7.97 (d, J = 7.6 Hz, 1H), 7.78 (d, J = 5.2 Hz, 1H), 7.57ꢀ7.55 (m,
2H), 7.36ꢀ7.27 (m, 3H), 7.16ꢀ7.10 (m, 4H), 7.02ꢀ6.93 (m, 3H), 2.43 (s, 3H). 13C NMR (100
MHz, CDCl3): δ 143.9, 140.9, 140.4, 140.1, 139.1, 139.1, 133.8, 131.3, 131.1, 128.8, 128.5,
128.3, 128.2, 127.2, 121.6, 121.4, 119.9, 113.5, 111.0, 21.3. HRMS [M + H]+ calculated for
C24H18N2:335.1548, found: 335.1550.
1-(4-methyl-2,6-di(naphthalen-2-yl)phenyl)-9H-pyrido[3,4-b]indole 3bc. White solid,
1
Yield: 88.7 mg, 87%; Rf (PE/EA = 20/1): 0.52. H NMR (400 MHz, CDCl3): δ 8.11 (d, J =
4 Hz, 1H), 7.83 (d, J = 8 Hz, 1H), 7.70ꢀ7.49 (m, 9H), 7.43 (s, 2H), 7.34 (d, J = 8 Hz, 2H),
7.28ꢀ7.24 (m, 4H), 7.16 (d, J = 12 Hz, 1H), 7.06 (m, 3H), 2.52 (s, 3H). 13C NMR (100 MHz,
CDCl3): δ 142.6, 139.9, 139.0, 138.8, 138.6, 135.3, 133.0, 132.0, 131.0, 128.2, 128.0, 127.4,
127.0, 125.8, 125.7, 121.7, 119.7, 113.3, 111.2, 21.4. HRMS [M + H]+ calculated for
C38H26N2: 511.2174, found: 511.2170.
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