Ullmann-Type Intramolecular C-O Reaction Toward Thieno[3,2-b]furan Derivatives with up to Six Fused Rings

Transcription

1 Ullmann-Type Intramolecular C-O Reaction Toward Thieno[3,2-b]furan Derivatives with up to Six Fused Rings Daoliang Chen,, Dafei Yuan,, Cheng Zhang,, Hao Wu,, Jianyun Zhang,, Baolin Li*, and Xiaozhang Zhu*,, School of Chemistry and Chemical Engineering, University of Chinese Academy of Sciences, Beijing , P. R. China Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing , P. R. China S1

2 Table of contents 1. Synthesis of compounds 3... S3 2. Optimization of the reaction conditions of 4l... S5 3. Proposed mechanism for intramolecular C-O Ullmann reaction... S6 4. DFT calculations... S7 5. CV spectra of C8-DTBDF... S9 6. OFET research of C8-DTBDF... S10 7. X-ray crystallographic analysis of BTBFs... S11 8. NMR spectra... S16 S2

3 1. Synthesis of compounds 3 Synthesis of compound 3a 3m: Table S1. The reaction substrate scope. Entry Product Yield (%) 1 3a b c d e f g h 78 S3

4 9 3i j k l m 81 Reaction conditions for general Suzuki coupling for synthesis of compounds 3: Compounds 1 (1 mmol), compounds 2 (1.5 mmol), Pd(PPh3)4, K2CO3 (4 mol), 1,4-dioxane (10 ml) and H2O (2 ml), 90 o C, 12 h. All reactions were conducted at 90 o C under N2 atmosphere. S4

5 2. Optimization of the reaction conditions of 4l Table S2. Optimization of the reaction conditions of 4l. Entry Metal Ligand Solvent Base Yield Time 1 CuI phen DMF K2CO3 18% 15 min 2 CuI phen DMF KOAc n.d. 15 min 3 CuI phen DMF NaHCO3 63% 1 h 4 CuI phen DMF LiOH trace 15 min 5 CuI phen DMF NaH2PO4 n.d. overnight All reactions were conducted at 90 o C under N2 atmosphere. S5

6 3. Proposed mechanism for intramolecular C-O Ullmann reaction Figure S1. Proposed mechanism for intramolecular Ullmann reaction. The proposed mechanism of the Ullmann reaction are widely believed to include two typical pathways, one is the radical mechanism, and the other is the Cu(III) mechanism. To gain mechanistic insights, we added 3 equivalent of butylated hydroxytoluene (BHT) as a radical quencher under the optimized reaction condition. The formation of the desired product was not inhibited, which suggests that no radical pathway was involved in the reaction. Therefore, we supposed that the reaction mechanism is an oxidative addition to form an aryl-cu(iii) phenoxide complex (C) that undergoes reductive elimination of the furan ring. As shown in Figure S1, firstly, intermediate A (the neutral form) was formed in the presence of base, which is in an equilibrium with the ion form B. Next, the copper(i) insertion of C-Br formed intermediate C (Cu III ) from intermediate A, and then reductive elimination occurred to afford the intramolecular cyclization product 4. S6

7 4. DFT calculations DFT calculation of BTBF Table S3. B3LYP/6-31G optimized standard orientation of BTBF Center Atomic Atomic Coordinates (Angstroms) Number Number Type X Y Z SCF Done: E(RB3LYP) = A.U. after 1 cycle Convg = D-08 -V/T = DFT calculation of BTBT Table S4. B3LYP/6-31G optimized standard orientation of BTBT Center Atomic Atomic Coordinates (Angstroms) Number Number Type X Y Z S7

8 SCF Done: E(RB3LYP) = A.U. after 15 cycles Convg = D-08 -V/T = S8

9 5. CV spectra of C8-DTBDF Measurements were carried out in a one-compartment cell under N2 atmosphere, equipped with a glassy-carbon electrode, a carbon counter electrode, and a Ag/AgCl reference electrode. The supporting electrolyte was a 0.1 mol/l dichloromethane solution of tetrabutylammonium perchlorate (TBAP). All potentials were corrected against Fc/Fc +. CV was measured with a scan rate of 100 mv/s. Figure S2. Cyclic voltammogram of C8-DTBDF in CH2Cl2 (HOMO: 5.42 ev). S9

10 6. OFET research of C8-DTBDF Table S5. OFET device performance Annealing Temperature Hole Mobility (cm 2 V 1 s 1 ) Avg (Max) Threshold Voltage (V) Avg (Min) Ion/Ioff Avg (Max) RT ( ) 14 ( 12) 10 5 (10 5 ) ( ) 22 ( 16) 10 5 (10 6 ) ( ) 23 ( 18) 10 4 (10 4 ) Figure S3. FET transfer characteristics and output curve. The highest occupied molecular orbital (HOMO) energy level of C8-DTBDF is determined by means of cyclic voltammetry (Figure S1) to be 5.42 ev below the vacuum level, which is suitable for OFET application. Bottom-gate bottom-contact OFETs were fabricated to investigate the semiconducting properties of C8-DTBDF. The semiconducting layers were spin-coated (in cholorform) onto octadecyltrichlorosilane-modified SiO2 (300 nm)/si substrates with pre-patterned gold source and drain electrodes. S10

11 7. X-ray crystallographic analysis of BTBFs X-ray crystallographic data of BTBF (4a), Cl-BTBF (4j), tbu-btbf (4d) and C8-DTBDF are listed in the Table S5. Table S6. X-ray crystallographic data of BTBF (4a) (CCDC No.: ), Cl-BTBF (4j) (CCDC No.: ), tbu-btbf (4d) (CCDC No.: ) and C8-DTBDF (CCDC No.: ). Compound 4a 4d CCDC No. CCDC CCDC Empirical formula C18 H16 O S C18 H16 O S Formula weight Temperature K K Wavelength Å Å Crystal system, space group Monoclinic, C 1 2/c 1 Monoclinic, P 1 21/c 1 Unit cell dimensions a = (14) Å = 90 b = 5.267(3) Å = (8) c = (9) Å = 90 a = (5) Å = 90 b = 5.977(3) Å = (6) c = (9) Å = 90 Volume 2002(2) Å (11) Å 3 Z, Calculated density 8, Mg/m 3 4, Mg/m 3 Absorption coefficient mm mm -1 F(000) Crystal size mm mm Theta range for data collection to deg to deg. Limiting indices -30<=h<=30, -6<=k<=6, -20<=l<=20-15<=h<=15, -7<=k<=7, -25<=l<=25 Reflections collected/unique 6561/2229 [R(int) = ] 9763/3135 [R(int) = ] Absorption correction Semi-empirical from equivalents Semi-empirical from equivalents Max. and min. transmission and and Refinement method Full-matrix least-squares on F 2 Full-matrix least-squares on F 2 Data / restraints / parameters 2229 / 0 / / 0 / 184 Goodness-of-fit on F Final R indices [I>2sigma(I)] R1 = , wr2 = R1 = , wr2 = R indices (all data) R1 = , wr2 = R1 = , wr2 = Largest diff. peak and hole and e.å and e. Å -3 S11

12 Compound 4j C8-DTBDF CCDC No. CCDC CCDC Empirical formula C14H7ClOS C30H38O2S2 Formula weight Temperature 173 K K Wavelength Å Å Crystal system, Monoclinic Triclinic space group P P -1 Unit cell dimensions a = (8) Å = 90 b = 3.842(2) Å = (14) c=13.114(10)å = 90 a = 6.657(3) Å = (7). b=8.177(4)å = (4). c = (5) Å = (8). Volume 536.0(6) Å (5) Å 3 Z, Calculated density 2, Mg/m 3 1, Mg/m 3 Absorption coefficient mm mm -1 F(000) Crystal size 0.23 x 0.12 x 0.07 mm x 0.08 x 0.03 mm 3 Theta range for data collection Limiting indices to to <=h<=14, -4<=k<=4, -16<=l<=17-8<=h<=8, -10<=k<=10, -16<=l<=16 Reflections collected/unique 6227 / 2394 [R(int) = ] 9042 / 3013 [R(int) = ] Absorption correction Semi-empirical from Semi-empirical from equivalents equivalents Max. and min. transmission and and Refinement method Full-matrix least-squares on F 2 Full-matrix least-squares on F 2 Data / restraints / parameters 2394 / 1 / / 0 / 155 Goodness-of-fit on F Final R indices [I>2sigma(I)] R1 = , wr2 = R1 = , wr2 = R indices (all data) R1 = , wr2 = R1 = , wr2 = Largest diff. peak and hole and e.å and e.å -3 S12

13 Thermal ellipsoid plots (50 % probability level) of BTBF (4a), Cl-BTBF (4j), tbu-btbf (4d) and C8-DTBDF are shown below. Figure S4. Thermal ellipsoid plots (50 % probability level) of BTBF (4a) Figure S5. Thermal ellipsoid plots (50 % probability level) of tbu-btbf (4d). Figure S6. Thermal ellipsoid plots (50 % probability level) of Cl-BTBF (4j). Figure S7. Thermal ellipsoid plots (50 % probability level) of C8-DTBDF. The packing mode of BTBF (4a) S13

14 Figure S8. The packing mode of BTBF (4a). The packing mode of BTBT is also included for comparison. The molecules of BTBF (4a) stack as a herringbone structure by C-H π (2.738 Å) interactions, and the π-π interaction distance is 3.41 Å, besides there is also substantial S-S interactions 3.47 Å, the O H bond distances between the neighboring molecules are 2.84 Å. The packing mode of 4d Figure S9. The packing mode of 4d. The packing structure of 4d is very interisting each two molecules packing by π-π interactions and dipole interactions with the distance 3.65 Å, and the packing structure of each dimer stacked by C-H π interactions with the distance 2.87 Å. S14

15 The packing mode of 4j Figure S10. The packing mode of 4j. 4j exhibits highly coplanar-conjugated frameworks due to the sulfur and oxygen bridges. The dihedral angle between the two outer benzene rings is only 0.5. The molecules arrange into a herringbone motif along the b-axis with an angle of 81.2 between the adjacent BTBF backbones. S S nonbonding interactions (3.473 Å) was observed along a-axis. Introduction of a chlorine substituent on BTBF backbone strongly influences the crystal packing. In the packing of 4j, each molecule stacks in a parallel fashion along b-axis with the interplane distance of about 3.46 Å and the tilt angle of about The adjacent stacks were linked through S S (3.555 Å) and S H nonbonding interactions to form a compressed highly ordered packing mode, which makes 4j an attractive candidate for device applications. S15

16 8. NMR spectra 2-(3-Bromobenzo[b]thiophene-2yl)phenol) (3a). S16

17 S17

18 2-(3-Bromothiophen-2-yl)phenol (3b) S18

19 S19

20 2-(3-Bromo-6-(tert-butyl)benzo[b]thiophen-2-yl)phenol (3c) S20

21 S21

22 2-(3-Bromobenzo[b]thiophene-2-yl)-5-(tert-butyl)phenol (3d) S22

23 S23

24 2-(3-Bromo-6-(tert-butyl)benzo[b]thiophen-2-yl)-5-(tert-butyl)phenol (3e) S24

25 S25

26 2-(3-Bromobenzo[b]thiophen-2-yl)-4-fluorophenol (3f) S26

27 S27

28 1-(2,3-Dibromobenzo[b]thiophen-6-yl)octan-1-one (3g) S28

29 S29

30 4-Bromo-2-(3-bromobenzo[b]thiophen-2-yl)phenol (3h) S30

31 S31

32 2-(3,6-Dibromobenzo[b]thiophen-2-yl)phenol (3i) S32

33 S33

34 2-(3-Bromobenzo[b]thiophen-2-yl)-4-chlorophenol (3j) S34

35 S35

36 2-(3-Bromo-5-chlorobenzo[b]thiophen-2-yl)phenol (3k) S36

37 S37

38 2-(3-bromo-5-chlorobenzo[b]thiophen-2-yl)-4-chlorophenol (3l) S38

39 S39

40 2-(3-bromo-5-chlorobenzo[b]thiophen-2-yl)-4-fluorophenol (3m) S40

41 S41

42 2,5-Bis(3-bromothiophen-2-yl)benzene-1,4-diol (3n) S42

43 S43

44 2,2 -(3,6-Dibromothieno[3,2-b]thiophene-2,5-diyl)diphenol (3o) S44

45 S45

46 Benzo[4,5]thieno[3,2-b]benzofuran (4a) S46

47 S47

48 Thieno[3,2-b]benzofuran (4b) S48

49 S49

50 2-(Tert-butyl)benzo[4,5]thieno[3,2-b]benzofuran (4c) S50

51 S51

52 7-(Tert-butyl)benzo[4,5]thieno[3,2-b]benzofuran (4d) S52

53 S53

54 2,7-Di-tert-butylbenzo[4,5]thieno[3,2-b]benzofuran (4e) S54

55 S55

56 8-Fluorobenzo[4,5]thieno[3,2-b]benzofuran (4f) S56

57 S57

58 1-(Benzo[4,5]thieno[3,2-b]benzofuran-2-yl)octan-1-one (4g) S58

59 S59

60 8-Bromobenzo[4,5]thieno[3,2-b]benzofuran (4h) S60

61 S61

62 2-Bromobenzo[4,5]thieno[3,2-b]benzofuran (4i) S62

63 S63

64 8-Chlorobenzo[4,5]thieno[3,2-b]benzofuran (4j) S64

65 S65

66 3-Chlorobenzo[4,5]thieno[3,2-b]benzofuran (4k) S66

67 S67

68 3,8-Dichlorobenzo[4,5]thieno[3,2-b]benzofuran (4l) S68

69 S69

70 3-Chloro-8- fluorobenzo[4,5]thieno[3,2-b]benzofuran (4m) S70

71 S71

72 DTBDF S72

73 S73

74 TTDBF S74

75 S75

76 C8-DTBDF S76

77 S77