6-Methyl-2,4-diphenyl­quinoline

Huo, X.; Xu, Y.; Li, X.; Pan, X.

doi:10.1107/S1600536808015651

organic compounds

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ISSN: 2056-9890

Volume 64| Part 7| July 2008| Page o1187

doi:10.1107/S1600536808015651

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6-Methyl-2,4-diphenylquinoline

Xing Huo,^a Yanfen Xu,^a Xinyun Li ^a and Xinfu Pan ^a ^*

^aDepartment of Chemistry, State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000, People's Republic of China
^*Correspondence e-mail: huox03@lzu.cn

(Received 9 April 2008; accepted 24 May 2008; online 7 June 2008)

The molecules of the title compound, C₂₂H₁₇N, are linked by weak interactions, among which the most prominent are C—H⋯π interactions. The dihedral angles between the phenyl rings and the quinoline ring system are 43.3 (3) and 21.4 (3)°. The title product resulted from a three-component reaction of benzaldehyde, 1-ethynylbenzene and p-toluidine via C—H activation of 1-ethynylbenzene catalyzed by CuI in the ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate.

Related literature

For related literature, see: Allen et al. (1987 ); Park & Alper (2005 ); Shi et al. (2004 ); Skraup (1880 ).

Experimental

Crystal data

C₂₂H₁₇N
M_r = 295.37
Orthorhombic, P 2₁ 2₁ 2₁
a = 7.766 (1) Å
b = 9.851 (1) Å
c = 20.756 (2) Å
V = 1588.0 (3) Å³
Z = 4
Mo Kα radiation
μ = 0.07 mm⁻¹
T = 294 (2) K
0.41 × 0.35 × 0.30 mm

Data collection

Bruker SMART CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.971, T_max = 0.979
8562 measured reflections
1720 independent reflections
1302 reflections with I > 2σ(I)
R_int = 0.051

Refinement

R[F² > 2σ(F²)] = 0.043
wR(F²) = 0.120
S = 1.04
1720 reflections
210 parameters
H-atom parameters constrained
Δρ_max = 0.17 e Å⁻³
Δρ_min = −0.14 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

Cg2 and Cg3 are the centroids of the C1–C6 and C14–C19 rings, respectively .

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C6—H6⋯Cg3ⁱ	0.93	2.75	3.551 (3)	145
C11—H11⋯Cg2ⁱ	0.93	2.92	3.726 (3)	146
Symmetry code: (i) $[x+{\script{3\over 2}}, -y+{\script{1\over 2}}, -z]$ .

Data collection: SMART (Bruker, 1998 ); cell refinement: SMART; data reduction: SAINT (Bruker, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808015651/fb2095sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808015651/fb2095Isup2.hkl

checkCIF report

Comment top

Quinolines and their derivatives are very important in medical chemistry because of their extensive occurrence in natural products. Also, quinolines possess a wide spectrum of biological activities. The classic method of quinoline synthesis is Skraup's procedure (Skraup, 1880). The synthesis of the title compound follows a study of transition-metal catalyzed multi-component reactions which is a powerful synthetic tool to access complex structures from simple precursors by a one-pot procedure (Shi et al., 2004; Park & Alper, 2005).

In the title compound, all the bond lengths are normal (Allen et al., 1987). The angle between both phenyl rings in the structure is 34.6 (3) °. The dihedral angle between the phenyl ring C1—C6 and the ring C14—C21/N1 is 43.3 (3) °. The dihedral angle between the C7—C12 phenyl ring and the C14—C21/N1 ring is 21.4 (3) °.

Related literature top

For related literature, see: Allen et al. (1987); Park & Alper (2005); Shi et al. (2004); Skraup (1880). Definition of the centroids: Cg3: C14–C19 Cg2: C1–C6.

Experimental top

The p-toluidine (1.5 mmol) and benzaldehyde(1.5 mmol) were taken along with a catalytic quantity of CuI (0.45 mmol) in ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate (5 ml) (Scheme 2). The resulting mixture was stirred at 298 K for 15 minutes. At this stage 1-ethynylbenzene (1 mmol) was quickly poured into the reaction mixture and the temperature was raised to 404 K, kept at this temperature for 6 hours, then cooled to room temperature. The product was extracted from the reaction mixture by addition of diethyl ether. (It was possible to recover ionic liquid layer and to use it again without any pretreatment.) The combined organic layer was concentrated and the desired product was isolated by silica gel column chromatography(petrol/EtOAc, 20:1). Colourless sheet crystals were recrystallized from the deuterated chloroform CDCl3 by evaporation in the course of several days. Their average size was 2.5-3 mm.

Computing details top

Data collection: SMART (Bruker, 1998); cell refinement: SMART (Bruker, 1998); data reduction: SAINT (Bruker, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. The molecular structure with the atom-numbering scheme. The displacement ellipsoids are drawn at the 30% probability level.
	Fig. 2. The formation of the title compound.

6-Methyl-2,4-diphenylquinoline top

Crystal data top

C₂₂H₁₇N	F(000) = 624
M_r = 295.37	D_x = 1.235 Mg m⁻³
Orthorhombic, P2₁2₁2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P2ac2ab	Cell parameters from 803 reflections
a = 7.766 (1) Å	θ = 2.3–24.5°
b = 9.851 (1) Å	µ = 0.07 mm⁻¹
c = 20.756 (2) Å	T = 294 K
V = 1588.0 (3) Å³	Block, colourless
Z = 4	0.41 × 0.35 × 0.30 mm

Data collection top

Bruker SMART CCD area-detector diffractometer	1720 independent reflections
Radiation source: fine-focus sealed tube	1302 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.052
ω scans	θ_max = 25.5°, θ_min = 2.0°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −8→9
T_min = 0.971, T_max = 0.979	k = −11→11
8562 measured reflections	l = −25→22

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: difference Fourier map
R[F² > 2σ(F²)] = 0.043	H-atom parameters constrained
wR(F²) = 0.120	w = 1/[σ²(F_o²) + (0.0684P)²] where P = (F_o² + 2F_c²)/3
S = 1.04	(Δ/σ)_max < 0.001
1720 reflections	Δρ_max = 0.17 e Å⁻³
210 parameters	Δρ_min = −0.14 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008)
67 constraints	Extinction coefficient: 0.009 (2)
Primary atom site location: structure-invariant direct methods

Crystal data top

C₂₂H₁₇N	V = 1588.0 (3) Å³
M_r = 295.37	Z = 4
Orthorhombic, P2₁2₁2₁	Mo Kα radiation
a = 7.766 (1) Å	µ = 0.07 mm⁻¹
b = 9.851 (1) Å	T = 294 K
c = 20.756 (2) Å	0.41 × 0.35 × 0.30 mm

Data collection top

Bruker SMART CCD area-detector diffractometer	1720 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	1302 reflections with I > 2σ(I)
T_min = 0.971, T_max = 0.979	R_int = 0.052
8562 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.043	0 restraints
wR(F²) = 0.120	H-atom parameters constrained
S = 1.04	Δρ_max = 0.17 e Å⁻³
1720 reflections	Δρ_min = −0.14 e Å⁻³
210 parameters

Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
N1	0.8369 (3)	0.4866 (3)	0.14992 (11)	0.0493 (6)
C1	0.6966 (4)	0.5970 (3)	0.34443 (12)	0.0453 (7)
C2	0.7800 (4)	0.5422 (3)	0.39763 (13)	0.0538 (8)
H2	0.8605	0.4733	0.3920	0.065*
C3	0.7440 (5)	0.5893 (4)	0.45891 (14)	0.0640 (9)
H3	0.7997	0.5513	0.4942	0.077*
C4	0.6258 (5)	0.6926 (4)	0.46804 (14)	0.0678 (10)
H4	0.6016	0.7238	0.5093	0.081*
C5	0.5439 (5)	0.7489 (3)	0.41549 (13)	0.0621 (9)
H5	0.4649	0.8188	0.4214	0.074*
C6	0.5788 (4)	0.7021 (3)	0.35440 (13)	0.0493 (7)
H6	0.5232	0.7409	0.3193	0.059*
C7	0.8147 (4)	0.7190 (3)	0.11564 (12)	0.0448 (7)
C8	0.9118 (4)	0.6959 (3)	0.06060 (13)	0.0562 (8)
H8	0.9718	0.6147	0.0562	0.067*
C9	0.9206 (5)	0.7918 (3)	0.01228 (14)	0.0647 (9)
H9	0.9870	0.7750	−0.0242	0.078*
C10	0.8318 (5)	0.9124 (3)	0.01757 (15)	0.0638 (9)
H10	0.8375	0.9767	−0.0152	0.077*
C11	0.7347 (4)	0.9371 (3)	0.07175 (14)	0.0592 (9)
H11	0.6745	1.0182	0.0758	0.071*
C12	0.7268 (4)	0.8410 (3)	0.12009 (13)	0.0524 (8)
H12	0.6608	0.8586	0.1565	0.063*
C13	0.7370 (3)	0.5530 (3)	0.27752 (13)	0.0434 (7)
C14	0.7596 (3)	0.4139 (3)	0.25973 (13)	0.0448 (7)
C15	0.7277 (4)	0.3018 (3)	0.30025 (13)	0.0492 (7)
H15	0.6855	0.3175	0.3415	0.059*
C16	0.7564 (4)	0.1704 (3)	0.28110 (15)	0.0522 (8)
C17	0.8282 (4)	0.1481 (3)	0.22001 (14)	0.0559 (8)
H17	0.8570	0.0602	0.2077	0.067*
C18	0.8566 (4)	0.2523 (3)	0.17834 (14)	0.0545 (8)
H18	0.9014	0.2342	0.1377	0.065*
C19	0.8189 (4)	0.3880 (3)	0.19587 (13)	0.0454 (7)
C20	0.8015 (4)	0.6132 (3)	0.16636 (13)	0.0447 (7)
C21	0.7571 (4)	0.6497 (3)	0.23033 (12)	0.0472 (7)
H21	0.7413	0.7407	0.2406	0.057*
C22	0.7120 (5)	0.0522 (3)	0.32401 (16)	0.0677 (10)
H22A	0.6644	0.0853	0.3637	0.102*
H22B	0.8141	0.0007	0.3329	0.102*
H22C	0.6291	−0.0046	0.3028	0.102*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0537 (14)	0.0477 (15)	0.0465 (14)	0.0033 (13)	0.0026 (11)	−0.0044 (11)
C1	0.0542 (16)	0.0405 (15)	0.0412 (15)	−0.0047 (14)	−0.0011 (13)	−0.0024 (13)
C2	0.0665 (19)	0.0507 (18)	0.0444 (16)	−0.0062 (16)	−0.0071 (14)	−0.0017 (13)
C3	0.086 (2)	0.062 (2)	0.0436 (16)	−0.012 (2)	−0.0136 (16)	−0.0016 (16)
C4	0.094 (3)	0.068 (2)	0.0423 (17)	−0.014 (2)	0.0028 (17)	−0.0100 (16)
C5	0.076 (2)	0.0515 (19)	0.0586 (18)	−0.0029 (18)	0.0090 (17)	−0.0136 (17)
C6	0.0576 (17)	0.0474 (17)	0.0429 (15)	−0.0015 (16)	0.0037 (13)	−0.0029 (14)
C7	0.0497 (16)	0.0444 (17)	0.0404 (14)	0.0003 (14)	−0.0010 (13)	−0.0034 (13)
C8	0.0662 (19)	0.0513 (19)	0.0512 (17)	0.0081 (17)	0.0083 (15)	−0.0005 (15)
C9	0.084 (2)	0.064 (2)	0.0465 (17)	0.002 (2)	0.0151 (16)	0.0002 (17)
C10	0.092 (2)	0.052 (2)	0.0480 (18)	−0.004 (2)	−0.0054 (18)	0.0059 (16)
C11	0.075 (2)	0.0471 (18)	0.0557 (18)	0.0086 (18)	−0.0039 (16)	0.0001 (15)
C12	0.0601 (17)	0.0519 (18)	0.0451 (15)	0.0038 (16)	0.0013 (14)	−0.0036 (15)
C13	0.0448 (16)	0.0426 (16)	0.0428 (14)	−0.0009 (14)	−0.0007 (13)	−0.0007 (13)
C14	0.0447 (16)	0.0441 (16)	0.0455 (15)	0.0025 (14)	−0.0010 (12)	−0.0017 (13)
C15	0.0521 (17)	0.0498 (18)	0.0458 (15)	−0.0017 (15)	−0.0033 (13)	0.0019 (13)
C16	0.0533 (18)	0.0454 (18)	0.0579 (17)	0.0014 (15)	−0.0086 (15)	0.0009 (15)
C17	0.0617 (18)	0.0445 (18)	0.0616 (19)	0.0077 (16)	−0.0076 (16)	−0.0066 (16)
C18	0.0588 (18)	0.0524 (19)	0.0522 (18)	0.0091 (17)	0.0026 (14)	−0.0061 (17)
C19	0.0471 (15)	0.0438 (17)	0.0453 (15)	0.0023 (14)	0.0005 (13)	−0.0021 (13)
C20	0.0452 (15)	0.0453 (17)	0.0437 (15)	−0.0013 (14)	−0.0009 (12)	−0.0006 (13)
C21	0.0549 (17)	0.0417 (16)	0.0451 (15)	0.0032 (14)	0.0004 (14)	−0.0040 (14)
C22	0.079 (2)	0.0488 (19)	0.076 (2)	−0.0005 (18)	−0.0066 (19)	0.0077 (18)

Geometric parameters (Å, º) top

N1—C20	1.322 (4)	C10—H10	0.9300
N1—C19	1.369 (3)	C11—C12	1.381 (4)
C1—C2	1.390 (4)	C11—H11	0.9300
C1—C6	1.396 (4)	C12—H12	0.9300
C1—C13	1.489 (4)	C13—C21	1.375 (4)
C2—C3	1.383 (4)	C13—C14	1.430 (4)
C2—H2	0.9300	C14—C15	1.410 (4)
C3—C4	1.384 (5)	C14—C19	1.426 (3)
C3—H3	0.9300	C15—C16	1.373 (4)
C4—C5	1.379 (4)	C15—H15	0.9300
C4—H4	0.9300	C16—C17	1.403 (4)
C5—C6	1.376 (3)	C16—C22	1.506 (4)
C5—H5	0.9300	C17—C18	1.361 (4)
C6—H6	0.9300	C17—H17	0.9300
C7—C12	1.385 (4)	C18—C19	1.416 (4)
C7—C8	1.388 (4)	C18—H18	0.9300
C7—C20	1.485 (4)	C20—C21	1.418 (4)
C8—C9	1.380 (4)	C21—H21	0.9300
C8—H8	0.9300	C22—H22A	0.9600
C9—C10	1.378 (5)	C22—H22B	0.9600
C9—H9	0.9300	C22—H22C	0.9600
C10—C11	1.376 (4)

C20—N1—C19	118.0 (2)	C11—C12—H12	119.2
C2—C1—C6	118.4 (3)	C7—C12—H12	119.2
C2—C1—C13	122.0 (3)	C21—C13—C14	117.8 (2)
C6—C1—C13	119.5 (2)	C21—C13—C1	119.1 (3)
C3—C2—C1	120.4 (3)	C14—C13—C1	123.1 (2)
C3—C2—H2	119.8	C15—C14—C19	118.1 (3)
C1—C2—H2	119.8	C15—C14—C13	125.1 (2)
C2—C3—C4	120.5 (3)	C19—C14—C13	116.8 (3)
C2—C3—H3	119.8	C16—C15—C14	122.5 (3)
C4—C3—H3	119.8	C16—C15—H15	118.8
C5—C4—C3	119.6 (3)	C14—C15—H15	118.8
C5—C4—H4	120.2	C15—C16—C17	118.3 (3)
C3—C4—H4	120.2	C15—C16—C22	121.4 (3)
C6—C5—C4	120.2 (3)	C17—C16—C22	120.3 (3)
C6—C5—H5	119.9	C18—C17—C16	121.4 (3)
C4—C5—H5	119.9	C18—C17—H17	119.3
C5—C6—C1	120.9 (3)	C16—C17—H17	119.3
C5—C6—H6	119.5	C17—C18—C19	121.0 (3)
C1—C6—H6	119.5	C17—C18—H18	119.5
C12—C7—C8	117.7 (3)	C19—C18—H18	119.5
C12—C7—C20	121.8 (2)	N1—C19—C18	118.0 (2)
C8—C7—C20	120.4 (3)	N1—C19—C14	123.6 (3)
C9—C8—C7	120.9 (3)	C18—C19—C14	118.3 (3)
C9—C8—H8	119.6	N1—C20—C21	122.1 (3)
C7—C8—H8	119.6	N1—C20—C7	117.7 (2)
C10—C9—C8	120.5 (3)	C21—C20—C7	120.2 (3)
C10—C9—H9	119.7	C13—C21—C20	121.3 (3)
C8—C9—H9	119.7	C13—C21—H21	119.4
C11—C10—C9	119.4 (3)	C20—C21—H21	119.4
C11—C10—H10	120.3	C16—C22—H22A	109.5
C9—C10—H10	120.3	C16—C22—H22B	109.5
C10—C11—C12	119.8 (3)	H22A—C22—H22B	109.5
C10—C11—H11	120.1	C16—C22—H22C	109.5
C12—C11—H11	120.1	H22A—C22—H22C	109.5
C11—C12—C7	121.6 (3)	H22B—C22—H22C	109.5

C6—C1—C2—C3	1.2 (4)	C13—C14—C15—C16	−178.1 (3)
C13—C1—C2—C3	177.5 (3)	C14—C15—C16—C17	3.2 (4)
C1—C2—C3—C4	−0.6 (5)	C14—C15—C16—C22	−176.6 (3)
C2—C3—C4—C5	−0.2 (5)	C15—C16—C17—C18	−5.1 (5)
C3—C4—C5—C6	0.4 (5)	C22—C16—C17—C18	174.6 (3)
C4—C5—C6—C1	0.2 (5)	C16—C17—C18—C19	1.8 (5)
C2—C1—C6—C5	−1.0 (4)	C20—N1—C19—C18	179.9 (3)
C13—C1—C6—C5	−177.3 (3)	C20—N1—C19—C14	1.8 (4)
C12—C7—C8—C9	0.3 (4)	C17—C18—C19—N1	−174.7 (3)
C20—C7—C8—C9	178.0 (3)	C17—C18—C19—C14	3.5 (5)
C7—C8—C9—C10	−0.5 (5)	C15—C14—C19—N1	172.8 (3)
C8—C9—C10—C11	0.4 (5)	C13—C14—C19—N1	−7.1 (4)
C9—C10—C11—C12	−0.1 (5)	C15—C14—C19—C18	−5.3 (4)
C10—C11—C12—C7	0.0 (5)	C13—C14—C19—C18	174.8 (3)
C8—C7—C12—C11	−0.1 (4)	C19—N1—C20—C21	4.1 (4)
C20—C7—C12—C11	−177.7 (3)	C19—N1—C20—C7	−177.7 (2)
C2—C1—C13—C21	−135.1 (3)	C12—C7—C20—N1	157.1 (3)
C6—C1—C13—C21	41.1 (4)	C8—C7—C20—N1	−20.5 (4)
C2—C1—C13—C14	43.6 (4)	C12—C7—C20—C21	−24.7 (4)
C6—C1—C13—C14	−140.2 (3)	C8—C7—C20—C21	157.8 (3)
C21—C13—C14—C15	−173.5 (3)	C14—C13—C21—C20	−1.0 (4)
C1—C13—C14—C15	7.8 (4)	C1—C13—C21—C20	177.8 (2)
C21—C13—C14—C19	6.3 (4)	N1—C20—C21—C13	−4.6 (4)
C1—C13—C14—C19	−172.4 (3)	C7—C20—C21—C13	177.2 (3)
C19—C14—C15—C16	2.0 (4)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C6—H6···Cg3ⁱ	0.93	2.75	3.551 (3)	145
C11—H11···Cg2ⁱ	0.93	2.92	3.726 (3)	146

Symmetry code: (i) x+3/2, −y+1/2, −z.

Experimental details

Crystal data
Chemical formula	C₂₂H₁₇N
M_r	295.37
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	294
a, b, c (Å)	7.766 (1), 9.851 (1), 20.756 (2)
V (Å³)	1588.0 (3)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.07
Crystal size (mm)	0.41 × 0.35 × 0.30

Data collection
Diffractometer	Bruker SMART CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.971, 0.979
No. of measured, independent and observed [I > 2σ(I)] reflections	8562, 1720, 1302
R_int	0.052
(sin θ/λ)_max (Å⁻¹)	0.606

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.043, 0.120, 1.04
No. of reflections	1720
No. of parameters	210
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.17, −0.14

Computer programs: SMART (Bruker, 1998), SAINT (Bruker, 1998), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C6—H6···Cg3ⁱ	0.93	2.75	3.551 (3)	145
C11—H11···Cg2ⁱ	0.93	2.92	3.726 (3)	146

Symmetry code: (i) x+3/2, −y+1/2, −z.

Acknowledgements

The authors thank the State Laboratory of Applied Organic Chemistry, Lanzhou University, for funding this study.

References

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