The synthesis and properties of pyrazino[2,3-g]quinoxaline-2,7-dione and pyrimido[4,5-g]quinazoline-4,9-dione based conjugated polymers and application in organic thin film transistors

Jesse Quinn, Chang Guo, Bin Sun, Yinghui He, Edward Jin, Adrian Chan, Lewis Ko and Yuning LiDepartment of Chemical Engineering, Univeristy of Waterloo

Overview

N

NH

O

N

N

O quinazolin-4(3H)-one

N

N

O

N

N

O2-methyl-3-(o-tolyl)quinazolin-4(3H)-one

(Methaqualone, Sedative)Cl

Cl

3-(2,6-dichlorophenyl)-2-ethylquinazolin-4(3H)-one(Cloroqualone, Sedative and Antitussive)

Br

3-(2-bromophenyl)-2-methylquinazolin-4(3H)-one(Mebroqualone, Sedative)

N

HN O

quinoxalin-2(1H)-one

N

N O

N

O2N

N

O

3-(4-(4-methoxyphenyl)piperazin-1-yl)-1-(4-nitrobenzyl)quinoxalin-2(1H)-one

(Aldose reductase inhibitors)

NH

N

O

SO ON

6-fluoro-4-(quinolin-8-ylsulfonyl)-3,4-dihydroquinoxalin-2(1H)-one(HIV-1 reverse transcriptase

inhibitors)

F

55

101099

44

N11O

O

N33

N88

22

N66

77R

R

Ar

ArN

N

ON

N

OR

R

Ar

Ar

pyrimido[4,5-g]quinazoline-4,9-dionequinazolin-4(3H)-one moiety

N

HN

Ar

pyrazino[2,3-g]quinoxaline-2,7-dionequinoxalin-2(1H)-one moiety

ON

NH

Ar

O N

HN

Ar

ON

NH

Ar

O

27

1

3

89

6 5 4

10

Potential semiconductors with polymerizable flanking units

Among the nitrogen containing natural products, quinazolinone and its isomer quinoxalinone represent the most important heterocyclic cores that complement many naturally occurring alkaloids as well as marketed pharmaceuticals. Substituted and unsubstituted quinazolinones and quinoxalinones exhibit broad biological and pharmaceutical properties:1-3

• Targetted protein inhibition• Sedative

• Antitussive

• Antimicrobial• Anti-inflammatory

• Antidepressant

Due to this undeniable importance of quinazolinone and quinoxalinone alkaloids in the pharmacological industry and their biological compatibility such material may be profoundly important to other fields of study.In the past two decades π-conjugated polymers have been extensively studied as channel semiconductors for organic thin film transistors (OTFTs). OTFTs have been utilized in many applications:

• Radio-frequency identification tags• Flexible displays

Here, we introduce two new nitrogen-containing building blocks, pyrimido[4,5-g]quinazoline-4,9-dione (PQ) and pyrazino[2,3-g]quinoxaline-2,7-dione (PQx). These large π-conjugated fused ring structures not only incorporate the quinazolinone or quinoxalinone moieties, but also create potential semiconductors. Such building blocks, with their intrinsic biological compatibility, may also find further application as key recognition elements in bio- or chemo-based OTFT sensors.

• Memory devices• Biological and Chemical sensors

Objectives

Gate

Insulator

SemiconductorSource Drain

Vd

Vg

Gate

Insulator

Vd

Vg

Time (s)0 500 1000 1500 2000 2500

0.02

0.00

0.06

0.04

0.10

0.08

0.14

0.12

10 ppm

20 ppm

30 ppm

35 ppm

Response

SemiconductorSource Drain

DESIRED ANALYTE

Curre

nt (A

)

Objectives:• PQ and PQx as channel

semiconductors for OTFTs• Multiparameter testing using

OTFT architecture• Ambient/Aqueous stability• Feasibility as a gas sensor• Feasibility as bio-sensor

NH2

H2N O

O

O

OOH

HOO

O

O

ONH2

H2N O

O

O

O

i) ii)

1 2

iii)

HN

NHO

O

OO

O

OS

S

iv) NHO

O

OHHO

SO

HN

SO

v) NO

O

OO

S

NS

vi)

3 45

N

NH

O

S

N

HN

O

S

vii) viii)

6 7 8

N

N

O

S

N

N

O

SR

R N

N

O

S

N

N

O

SR

R

Br

Br

N

N

N

N

S

O

O

S

C12H25

C10H21

C10H21

C12H25

Arn

H2N

H2N

NH2

NH2

S OHO

O

NH

N

N

HN

S

O

O

S

N

N

N

N

S

O

O

S

N

N

N

N

S

O

O

S

Br

Br

BrC12H25

C10H21C10H21

C12H25

C10H21

C12H25

C10H21

C12H25

C10H21

C12H25

SS

S

S

PPQx2T-BT-24

PPQx2T-TT-24

Ar

i)

ii)

iii) iv)

ArSn Sn

PQx2T-H

PQx2T-24

PQx2T-Br-24

iso-PQx2T-H

+

N

N

N

N

S

OC10H21

C12H25

iso-PQx2T-24

OC10H21

C12H25

S+

PQx2T-24

N

HN

N

HN

S

O O

S

SSSn Sn

N

NN

N

O

O

S

S R

RS S

n

PPQ2T-BT-R

ix) C18H37

C18H37

-24 -40

**C10H21

C12H25

R =

PQ and polymer synthesis. Reagents and conditions: (i) toluene, ammonium acetate, catalytic amount of acetic acid, 16 h (95%); (ii) n-butanol, sulfur, gentle reflux, 18 h (90%); (iii) DCM, 2-thiophenecarbonyl chloride, pyridine, 0 °C, 30 min, rt, 18 h (79%); (iv) ethanol, lithium hydroxide, 60 °C, 3 h (86%); (v) acetic anhydride, reflux, 3 h (78%); (vi) ammonium acetate, 170 °C, 1 h, 30% sodium hydroxide, ethanol, reflux, 1 h (95%); (vii) DMF, K2CO3, 130 °C, 16 h (73%); (viii) NBS, chloroform, 0 °C, rt, overnight (75%);4 (ix) Pd2(dba)3, P(o-tolyl)3, chlorobenzene, 130 °C, 48 h.5 PQx and polymer synthesis. Reagents and conditions: (i) acetic acid/reflux/overnight; (ii) K2CO3/DMF/130 °C; (iii) NBS/chloroform; (iv) Pd2(dba)3/P(o-tolyl)3/chlorobenzene/130 °C.6

Experimental

Results

(A-C) Reflectance mode XRD with AFM image insets of PPQ2T-BT-24 (2 µm x 2 µm), PPQx2T-BT-24 (2 µm x 2 µm) and PPQx2T-TT-24 (4 µm x 4 µm) thin films (~35 nm) spin-coated on dodecyltrichlorosilane-modified SiO2/Si substrates and annealed at different temperatures with Cu Kα radiation (λ = 0.15406 nm). PPQ2T-BT-40 (not shown) followed suit with PPQ2T-BT-24.5,6

TGA thermograms of PPQ2T-BT-24, and PPQ2T-BT-40 (A) and PPQx2T-BT-24, and PPQx2T-TT-24 (B) with a heating rate of 10 °C min-1 under nitrogen. No visible endothermic/exothermic transitions were observed on their DSC thermograms (not shown).5,6

ConclusionPreliminary results demonstrate that PQ and PQx are promising new building blocks for polymeric semiconductors:

AcknowledgementsThe financial support of this work from the Natural Sciences and Engineering Research Council (NSERC) of Canada (Discovery Grants #402566-2011) is greatly acknowledged.

References1. Zhou et al. MedChemComm 2014, 5 (10), 441 DOI: 10.1039/c3md00337j.2. Hussain et al. Eur. J. Med. Chem. 2014, 80, 383–392 DOI: 10.1016/j.ejmech.2014.04.047.3. Ghosh et al. RSC Adv. 2016, 6 (33), 27378–27387 DOI: 10.1039/C6RA00855K.4. Quinn et al. Tetrahedron Lett. 2015, 56 (17), 2280–2282 DOI: 10.1016/j.tetlet.2015.03.085.5. Quinn et al. J. Mater. Chem. C 2015, 3 (45), 11937–11944 DOI: 10.1039/C5TC02472B.6. Quinn et al. RSC Adv. 2016, 6 (26), 22043–22051 DOI: 10.1039/C5RA26227E.

• Good thermal stability• Lewis/organic acid-base adduct formation

• Unipolar semiconductor performance• Ambipolar semiconductor performance

Output and transfer curves of an OTFT device with a thin film of PPQ2T-BT-24 (A), PPQ2T-BT-40 (B), PPQx2T-BT-24 (C,D), and PPQx2T-TT-24 (E) annealed at 250 °C (A), 300 °C (B), and 200 °C (C-E), respectively. Bottom right image represents the bottom gate bottom contact device architecture. Device dimensions: channel length (L) = 30 µm; channel width (W) = 1000 µm. Performance ~10-3 cm2 V-1 s-1 (A-D) and ~10-2 cm2 V-1 s-1 (E).5,6

Gate

Insulator

SemiconductorSource Drain

Vd

Vg

30 μm

PQ

PQx

Name Egopt (eV) Eg

ec (eV) EHOMO (eV) ELUMO (eV) Mn (kDa) PDI

PPQ2T-BT-24 2.03 - -5.30 - 38.9 3.68

PPQ2T-BT-40 2.03 - -5.29 - 43.5 2.95

PPQx2T-BT-24 1.66 1.95 -5.54 -3.59 24.6 7.86

PPQx2T-TT-24 1.82 2.02 -5.54 -3.52 14.4 2.05

GPC data obtained using HT-GPC (140 °C). No reduction peak observed for PQ polymers in CV.5,6

(A–F) UV-Vis-NIR absorption spectra of PPQ2T-BT-24, PPQx2T-BT-24, and PPQx2T-TT-24 in chlorobenzene with various concentrations of TFA and BBr3, respectively, under nitrogen with a molar concentration of the polymer repeat unit at ~1X10-5 M.5,6

The next step is to demonstrate ambient condition stability and test material sensitivty and selectivity to specific gaseous analytes.