New Columnar Liquid Crystal Materials Based on Luminescent 2-Methoxy-3-Cyanopyridines

Supporting Information

New Columnar Liquid Crystal Materials Based on Luminescent 2-Methoxy-3-cyanopyridines

Ahipa. T. N.,a Vijith Kumar,b Airody Vasudeva Adhikari*a

a Department of Chemistry, National Institute of Technology Karnataka, Surathkal, Mangalore 575025, India.

b Solid State Structural Chemistry Unit, Indian Institute of Science, Bangalore - 560 012, India.

* Corresponding and presenting author. Tel.: +91 8242474046; fax: +918242474033.

E-mail addresses: , , .

Contents

General
Synthesis and structural Characterization
X-ray Crystallography
PXRD data
References

1.General

Solvents and reagents were purchased from Aldrich, Merck, and spectrochem and were used without further purification unless otherwise noted. The synthesis of target mesogens containing 2-methoxy-3-cyanopyridine as central core is described in Scheme S1. Analytical TLC was performed on pre-coated silica gel plates (Merck 60 Kieselgel F 254) and visualized with UV light, in order to check purity of sample. Infrared spectra of all compounds were recorded on a Nicolet Avatar 5700 FTIR (Thermo Electron Corporation). The UV-visible and photoluminescence spectra were taken in GBC Cintra 101 and Perkin Elmer LS55 fluorescence spectrophotometers respectively. 1H and 13C NMR spectra were recorded on a Bruker Avance DPX spectrometer at 400 MHz using CDCl3 or DMSO-d6 as the solvent, with tetramethylsilane as internal standard. Elemental analyses were performed on a Flash EA1112 analyzer (Thermo Electron Corporation). Melting points were determined by a Stuart apparatus and reported without correction. The sequence of phases and phase transition temperatures were identified by observing the textures and their changes under the polarizing optical microscope (POM). Polarized light microscopic studies were carried out using a Leitz Ortholux II Pol-BK microscope equipped with a Mettler FP82HT hot stage was used for temperature control, which enabled temperature stabilization within ±0.1 K. The phase transition temperatures were determined using a SHIMADZU DSC-60 differential scanning calorimeter with a heating rate of 10 °C min-1 (the apparatus was calibrated with indium, 156.6 °C). The about 3 mg of sample was hermetically sealed in an aluminium pan and placed in a nitrogen atmosphere.

2.Synthesis and structural Characterization

Scheme S1 Synthesis of cyanopyridine mesogen. Reagents and conditions: (i) KOH / EtOH, rt; (ii) Malononitrile, NaOMe, MeOH, rt

General procedure for the synthesis of compounds 1a-f and 2a-f.

The 4-n-alkoxyacetophenones 1a-f were prepared from 4-hydroxyacetophenone by reaction with the corresponding alkyl bromide following standard procedures [1, 2]. The 4-n-alkoxybenzaldehyde or 3-methoxy/ethoxy substituted 4-n-alkoxybenzaldehydes 2a-f were prepared from 4-hydroxybenzaldehyde or 3-methoxy/ethoxy substituted 4-hydroxybenzaldehyde by reacting with the corresponding alkyl bromide according to literature [3].Further,all the obtained analytical data were in agreement with the reported data.

General procedure for the synthesis of chalcones (3a-f).

A mixture of 4-n-alkoxyacetophenones 1a-f (1 equivalent) and corresponding 4-n-alkoxybenzaldehyde or or 3-methoxy/ethoxy substituted 4-n-alkoxybenzaldehydes 2a-f (1 equivalent) was taken in ethanol. To this added aqueous solution of potassium hydroxide (1.2 equivalents) slowly. Reaction mixture was then stirred at room temperature for 4 h. The precipitated product was filtered. The crude product was purified by recrystallization from ethanol.

1,3-Bis(4-(hexyloxy)phenyl)prop-2-en-1-one (3a).

Yellow solid, yield 78 %, m.p. 76-77 °C 1H NMR (400 MHz, DMSO-d6) 7.90 (d, J= 15.4 Hz, 1H, Olefinic H), 7.70 (d, J= 8.6 Hz, 2H, Ar-H), 7.56 (d, J= 15.4 Hz, 1H, Olefinic H), 7.19 (d, J= 8.6 Hz, 2H, Ar-H), 6.96 (d, J= 8.4 Hz, 2H, Ar-H), 6.72 (d, J= 8.4 Hz, 2H, Ar-H), 3.94 (t, J=6.6 Hz, 4H, Ar-OCH2-), 1.74-1.71 ( q, 4H, -OCH2-CH2-), 1.50-1.26 (m, 12H, -CH2-), 0.96 (t, J= 6.8 Hz, 6H, -CH3). 13C NMR (100 MHz, CDCl3) δ (ppm); 189.7, 163.3, 156.7, 145.2, 130.5, 129.5, 127.0, 126.8, 121.4, 114.3, 68.9, 31.9, 29.7, 25.7, 22.8, 14.1. IR (ATR, cm-1): 2918, 2853, 1648, 1604, 1579, 1245, 1019, 824.Anal.Calcd.For.C27H36O3: C. 79.37; H. 8.88; Found: C. 79.61; H. 8.97.

3-(4-(Hexyloxy)-3-methoxyphenyl)-1-(4-(hexyloxy)phenyl)prop-2-en-1-one (3b).

Yellow solid, yield 71 %, m.p. 82-83 °C, 1H NMR (400 MHz, DMSO-d6) 7.88 (d, J= 15.4 Hz, 1H, Olefinic H), 7.70 (d, J= 8.6 Hz, 2H, Ar-H), 7.56 (d, J= 15.4 Hz, 1H, Olefinic H), 6.96 (d, J= 8.6 Hz, 2H, Ar-H), 6.75 (d, J= 8.4 Hz, 1H, Ar-H), 6.70 (s, 1H, Ar-H), 6.61 (d, J= 8.4 Hz, 1H, Ar-H), 3.94 (t, J= 6.8 Hz, 4H, Ar-OCH2), 3.73 (s, 3H,Ar-OCH3), 1.74-1.71 (q, 4H, -OCH2-CH2-), 1.54-1.26 (m, 12H, -CH2-), 0.96 (t, J= 6.8 Hz, 6H, -CH3). 13C NMR (100 MHz, CDCl3) δ (ppm); 190.6, 163.3, 149.8,145.2, 130.5, 129.5, 127.8,121.4, 119.3, 114.9, 111.2, 68.9, 56.2, 31.9, 29.7, 25.7, 22.8, 14.1. IR (ATR, cm-1):2926, 2847, 1651, 1603, 1584, 1242, 821.Anal.Calcd.For.C28H38O4: C. 76.68; H. 8.73; Found: C. 76.43; H. 8.91.

3-(3-Ethoxy-4-(hexyloxy)phenyl)-1-(4-(hexyloxy)phenyl)prop-2-en-1-one (3c).

Yellow solid, yield 68 %, m.p. 80-81°C, 1H NMR (400 MHz, DMSO-d6) 8.15 (d, J= 8.6 Hz, 2H, Ar-H), 7.79 (d, J= 15.4 Hz, 1H, Olefinic H), 7.63 ( d, J= 15.4 Hz, 1H, Olefinic H),7.5 (s, 1H, Ar-H), 7.34 (d, J= 8.6 Hz, 1H, Ar-H), 7.05 (d, J= 8.4 Hz, 2H, Ar-H). 6.99 (d, J= 8.4 Hz, 1H, Ar-H), 4.10-4.00 (m, 6H, Ar-OCH2-), 1.77 -1.69 (m, 4H, -OCH2-CH2-), 1.46-1.26 (m, 15H, -CH2-), 0.88 (t, J= 6.8 Hz, 6H, -CH3). 13C NMR (100 MHz, CDCl3) δ (ppm); 189.7, 163.3, 146.6, 145.9, 130.5, 129.5, 121.4, 118.6, 114.9, 111.3, 68.9, 65.0, 31.9, 29.7, 25.7, 22.8, 14.1. IR (ATR, cm-1): 2923, 2849, 1646, 1600, 1573, 1244, 825. Anal.Calcd.For.C29H40O4: C. 76.95; H. 8.91; Found: C. 77.13; H. 8.85.

1,3-Bis(4-(octyloxy)phenyl)prop-2-en-1-one (3d).

Yellow solid, yield 79 %, m.p. 77-78 °C, 1H NMR (400 MHz, DMSO-d6) 8.12 (d, 8.8 Hz, 2H, Ar-H), 7.78 (d, J= 15.4 Hz, 1H, Olefinic H), 7.64 (d, J= 15.4 Hz, 1H, Olefinic), 7.19 (d, J= 8.4 Hz, 2H, Ar-H), 6.96 (d, J= 8.8 Hz, 2H, Ar-H), 6.99 (d, J= 8.4 Hz, 2H, Ar-H), 4.08-3.98 (m, 4H, Ar-OCH2-), 1.72- 16.9 (m, 4H, -OCH2-CH2-), 1.52-1.29 (m, 20H, -CH2-), 0.88 (t, J= 6.8 Hz, 6H, -CH3). 13C NMR (100 MHz, CDCl3) δ (ppm); 189.7, 163.3, 156.7, 145.2, 130.5, 127.0, 121.4, 114.3, 68.9, 31.9, 29.7, 26.0, 22.8, 14.1. IR (ATR, cm-1): 2931, 2851, 1648, 1598, 1577, 1241, 824. Anal.Calcd.For.C31H44O3: C. 80.13; H. 9.54; Found: C. 80.35; H. 9.47.

3-(3-Methoxy-4-(octyloxy)phenyl)-1-(4-(octyloxy)phenyl)prop-2-en-1-one (3e).

Yellow solid, yield 79 %, m.p. 87-88 °C, 1H NMR (400 MHz, DMSO-d6) 8.12 (d, 8.8 Hz, 2H, Ar-H), 7.78 (d, J= 15.2 Hz, 1H, Olefinic H), 7.64 (d, 15.2 Hz, 1H, Olefinic H), 7.50 (s, 1H, Ar-H), 7.33 (d, J= 8.8 Hz, 1H, Ar-H), 7.04 (d, J= 8.2 Hz, 2H, Ar-H), 6.99 (d, J= 8.2 Hz, 1H, Ar-H), 4.08- 3.98 (m, 4H, -OCH2-), 3.85 (s, 3H, Ar-OCH3), 1.76-1.63 (m, 4H, -OCH2-CH2-), 1.45-1.28 (m, 20H, -CH2-), 0.86 (t, J= 6.8 Hz, 6H, -CH3). 13C NMR (100 MHz, CDCl3) δ (ppm); 190.6, 163.3, 149.8, 145.2, 130.5, 129.5, 127.8, 121.4, 119.3, 114.9, 111.2, 68.9, 56.2, 31.9, 29.4. 26.0, 22.8, 14.1. IR (ATR, cm-1): 2928, 2852, 1646, 1600, 1579, 822. Anal.Calcd.For.C32H46O4: C. 77.69; H. 9.37; Found: C. 77.46; H. 9.41.

3-(3-Ethoxy-4-(octyloxy)phenyl)-1-(4-(octyloxy)phenyl)prop-2-en-1-one (3f).

Yellow solid, yield 74 %, m.p. 85-86.1 °C, 1H NMR (400 MHz, DMSO-d6) 8.12 (d, J= 8.8 Hz, 2H, Ar-H), 7.77 (d, J= 15.2 Hz, 1H, Olefinic H), 7.62 (d, J= 15.2 Hz, 1H, Olefinic H), 7.50 (s, 1H, Ar-H), 7.33 (d, J= 8.8 Hz, 1H, Ar-H), 7.05 (d, J= 8.2 Hz, 2H, Ar-H), 6.99 (d, J= 8.2 Hz, 1H, Ar-H), 4.13-3.99 (m, 6H, -OCH2-), 1.74-1.69 (m, 4H, -OCH2-CH2-), 1.41-1.26 (m, 23H, -CH2-), 0.84 (t, J=6.4 Hz, 6H, -CH3). 13C NMR (100 MHz, CDCl3) δ (ppm); 189.2, 163.3, 146.6, 145.2, 130.5, 127.4, 121.4, 118.6, 114.9, 111.3, 68.9, 65.0, 31.9, 29.7, 26.0, 22.8, 14.1. IR (ATR, cm-1): 2933, 2855, 1644, 1602, 1577, 824.Anal.Calcd.For.C33H48O4: C. 77.91; H. 9.51; Found: C. 78.15; H. 9.48.

General procedure for the synthesis of cyanopyridines (4a-f).

To a mixture of compounds 3a-f (1 equivalent) andmalononitrile (1 equivalent) was added slowly freshly prepared solution of sodium methoxide (20 equivalent of sodium in 10 ml of methanol) with continuous stirring at room temperature. Stirring was continued until the precipitate separates out. The solid separated was collected by filtration, washed with methanol and recrystallized from ethanol.

4,6-Bis(4-(hexyloxy)phenyl)-2-methoxynicotinonitrile (4a).

Yellow solid, yield 72 %. 1H NMR (400 MHz, CDCl3) δ (ppm) 8.04 (d, J= 8.8 Hz, 2H, Ar-H), 7.60 (d, J= 8.8 Hz, 2H, Ar-H), 7.36 (s, 1H, Ar-H(pyridine)), 7.02-6.97 (m, 4H, Ar-H), 4.16 (s, 3H, -OMe of pyridine), 4.03-4.00 (m, 4H, -OCH2-), 1.84-1.79 (m, 4H, -OCH2CH2-), 1.51-1.35 (m, 12H, -CH2-), 0.91 (t, J=7 Hz, 6H, -CH3). 13C NMR (100 MHz, CDCl3) δ (ppm); 165.12, 161.20, 160.64, 157.49, 156.04, 129.77, 129.52, 128.76, 128.48, 116.19, 114.86, 114.72, 112.23, 91.53, 68.19, 54.37, 31.55, 29.14, 25.68, 22.58, 14.00. IR (ATR, cm-1): 2937, 2857, 2213.9, 1578, 1235, 1017, 828. Anal.Calcd.For.C31H38N2O3: C. 76. 51; H. 7.87; N. 5.76; Found: C. 76.72; H. 7.83; N. 5.69.

4-(4-(Hexyloxy)-3-methoxyphenyl)-6-(4-(hexyloxy)phenyl)-2-methoxynicotinonitrile (4b). White solid, yield 68%. 1H NMR (400 MHz, CDCl3) δ (ppm) 8.05 (d, J= 8.8 Hz, 2H, Ar-H), 7.39 (s, 1H, Ar-H (pyridine)), 7.21 (d, J = 10.2 Hz, 2H, Ar-H), 6.99 (d, J= 8.8 Hz, 3H, Ar-H), 4.17 (s, 3H, -OMe of pyridine), 4.08- 4.01 (m, 4H, -OCH2-), 3.94 (s, 3H, OMe of Aromatic), 1.89-1.79 (m, 4H, -OCH2CH2- ), 1.54-1.36 (m, 12H, -CH2-), 0.91 (t, J= 7.2 Hz, 6H, -CH3 ). 13C NMR (100 MHz, CDCl3) δ (ppm); 165.15, 161.24, 157.54, 156.15, 150.24, 149.47, 129.73, 121.33, 116.20, 114.75, 112.73, 112.25, 112.03, 91.60, 69.13, 68.22, 56.28, 54.41, 31.56, 29.15, 29.05, 25.69, 25.63, 22.58, 14.01. IR (ATR, cm-1): 2929, 2859, 2206, 1579, 1251, 1014, 830. Anal.Calcd.For.C32H40N2O4: C. 74.39; H. 7.80; N. 5.42; Found: C. 74.58; H. 7.83; N. 5.37.

4-(3-Ethoxy-4-(hexyloxy)phenyl)-6-(4-(hexyloxy)phenyl)-2-methoxynicotinonitrile (4c).

White solid, yield 75 %. 1H NMR (400 MHz, CDCl3) δ (ppm) 8.05 ( d, J= 8.8 Hz, 2H, Ar-H), 7.38 (s, 1H, Ar-H(pyridine)), 7.21 (d, J= 10.2 Hz, 2H, Ar-H), 6.98 (d, J= 8.8 Hz, 3H, Ar-H), 4.19 (m, 5H, -OMe of pyridine, -OCH2-CH3), 4.09-4.01 (m, 4H, -OCH2-), 1.89-1.79 (m, 4H,-OCH2CH2-), 1.54- 1.33 (m, 15H, -CH2-), 0.91 (t, J= 6.8 Hz, 6H, -CH3). 13C NMR (100 MHz, CDCl3) δ (ppm); 165.15, 161.23, 157.50, 156.18, 150.74, 148.89, 129.76, 128.88, 128.78, 121.46, 116.21, 114.75, 114.01, 113.37, 112.29, 91.59, 69.26, 68.22, 65.05, 54.40, 31.56, 29.16, 29.08, 25.69, 25.65, 22.59, 14.86, 14.00. IR (ATR, cm-1):2921, 2860, 2215, 1579, 1251, 1032, 840. Anal.Calcd.For.C33H42N2O4: C. 74.69; H. 7.98; N. 5.28; Found; C. 74.91; H. 7.93; N. 5.32.

2-Methoxy-4,6-bis(4-(octyloxy)phenyl)nicotinonitrile (4d).

White solid, yield 65 %. 1H NMR (400 MHz, CDCl3) δ (ppm) 8.04 (d, J= 8.8Hz, 2H, Ar-H), 7.60 (d, J= 8.8 Hz, 2H, Ar-H), 7.36 (s, 1H, Ar-H(pyridine)), 7.02-6.97 (m, 4H, Ar-H), 4.16 (s, 3H, -OMe of pyridine), 4.03-4.00 (m, 4H, -OCH2-), 1.84-1.79 (m, 4H, -OCH2CH2-), 1.51-1.35 (m, 20 H, -CH2-), 0.91 (t, J=7 Hz, 6H, -CH3). 13C NMR (100 MHz, CDCl3) δ (ppm); 164.92, 157.15, 156.37, 156.14, 129.68, 128.03, 117.05, 114.96, 108.69, 93.32, 55.45, 31.96, 29.72, 26.01, 22.83, 14.17. IR (ATR, cm-1):2916, 2848, 2207, 1590, 1243, 1034, 836. Anal.Calcd.For.C35H46N2O3: C. 77.45; H. 8.54; N. 5.16; Found: C. 77.68; H. 8.47; N. 5.22.

2-Methoxy-4-(3-methoxy-4-(octyloxy)phenyl)-6-(4-(octyloxy)phenyl)nicotinonitrile (4e).

White solid, yield 62 %. 1H NMR (400 MHz, CDCl3) δ (ppm) 8.05 (d, J=8.8 Hz, 2H, Ar-H), 7.39 (s, 1H, Ar-H(pyridine)), 7.21 (d, J=10.2 Hz, 2H, Ar-H), 7.00 (d, J= 8.8Hz, 3H, Ar-H), 4.17 (s, 3H, -OMe of pyridine), 4.09-4.01(m, 4H, -OCH2-), 3.94 (s, 3H, -OMe of Aromatic), 1.89-1.79 (m, 4H,-OCH2CH2- ), 1.54-1.35 (m, 20 H, -CH2-), 0.89 (t, J=6.8 Hz, 6H, -CH3). 13C NMR (100 MHz, CDCl3) δ (ppm); 165.15, 161.24, 157.54, 156.15, 150.24, 149.46, 129.73, 128.79, 121.33, 116.20, 114.75, 112.72, 112.25, 112.01, 91.60, 69.13, 68.22, 56.28, 54.41, 31.80, 29.33, 29.21, 29.08, 26.02, 25.95, 22.64, 14.07. IR (ATR, cm-1): 2923, 2855, 2212, 1580, 1252, 1022, 826. Anal.Calcd.For. C36H48N2O4: C.75.49; H.8.45; N. 4.89; Found: C. 75.66; H. 8.51; N. 4.82.

4-(3-Ethoxy-4-(octyloxy)phenyl)-2-methoxy-6-(4-(octyloxy)phenyl)nicotinonitrile (4f).

white solid, yield 69 %. 1H NMR (400 MHz, CDCl3) δ (ppm) 8.05 (d, J=8.8 Hz, 2H, Ar-H), 7.38 (s, 1H, Ar-H(pyridine)), 7.21 (d, J= 10.2 Hz, 2H, Ar-H), 6.98 (d, J=8.8 Hz, 3H, Ar-H), 4.19 (m, 5H, -OMe of pyridine, -OCH2-CH3), 4.09-4.01 (m, 4H, -OCH2-), 1.89-1.79 (m, 4H,-OCH2CH2-), 1.54- 1.33 (m, 23 H, -CH2-, -OCH2-CH3), 0.91 (t, J= 6.8 Hz, 6H, -CH3). 13C NMR (100 MHz, CDCl3) δ (ppm); 165.15, 161.22, 157.50, 156.17, 150.73, 148.88, 129.75, 128.87, 128.78, 121.45, 116.21, 114.75, 114.00, 113.37, 112.28, 91.58, 69.26, 68.22, 65.05, 54.40, 31.80, 29.33, 29.22, 29.12, 26.02, 25.97, 22.65, 14.86, 14.08. IR (ATR, cm-1):2918, 2854, 2218, 1579, 1248, 1031,824. Anal.Calcd.For. C37H50N2O4: C. 75.73; H. 8.59; N. 4.77; Found: C. 75.55; H. 8.52; N.4.73.

Fig. S1 1H NMR spectrum of 4a (400 MHz, CDCl3)

Fig. S2 13C NMR spectrum of 4a (400 MHz, CDCl3)

Fig. S31H NMR spectrum of 4b (400 MHz, CDCl3)

Fig. S413C NMR spectrum of 4b (400 MHz, CDCl3)

Fig. S51H NMR spectrum of 4c (400 MHz, CDCl3)

Fig.S613C NMR spectrum of 4c (400 MHz, CDCl3)

Fig. S71H NMR spectrum of 4d (400 MHz, CDCl3)

Fig. S813C NMR spectrum of 4d (400 MHz, CDCl3)

Fig. S9 1H NMR spectrum of 4e (400 MHz, CDCl3)

Fig.S1013C NMR spectrum of 4e (400 MHz, CDCl3)

Fig. S111H NMR spectrum of 4f (400 MHz, CDCl3)

Fig. S1213C NMR spectrum of 4f (400 MHz, CDCl3)

3.X-ray Crystallography

Single crystal X-ray diffraction data sets were collected on an Oxford Xcalibur (Mova) diffractometer [4] equipped with an EOS CCD detector using MoKα radiation (λ= 0.71073 Å). The crystal was maintained at a desired temperature during data collection using the Oxford Instruments Cryojet-HT controller [5]. Structures were solved by direct methods using SHELXS-97 and refined against F2 using SHELXL-97 [6]. H-atoms were fixed geometrically and refined isotropically. The WinGX package [7] was used for refinement and production of data tables and ORTEP-3 [8] for structure visualization and making the molecular representations. Analysis of the H-bonded and π ··· π interactions was carried out using PLATON [9] for the two structures. Packing diagrams were generated by using MERCURY [10]. A summary of the crystallographic data and structural refinement details of compounds 4a and 4b are given in Table S1.

Table S1 Crystallographic data and structure refinement parameters of compounds 4a and 4b

Compound / 4a / 4b
Formula / C31H38N2O3 / C32H40N2O4
Formula weight / 486.63 / 516.66
CCDC number / 916621 / 916818
Temperature (K) / 110(2) / 110 (2)
Crystal form / Block / Block
Color / Colorless / Colorless
Crystal system / Monoclinic / Triclinic
Space group / P21/c / P-1
a (Å) / 24.942(2) / 12.041(1)
b (Å) / 15.928(3) / 16.162(1)
c (Å) / 13.704(1) / 17.012(4)
α (°) / 90 / 69.175(2)
β (°) / 94.739(4) / 73.371(3)
γ (°) / 90 / 69.132(3)
Volume (Å3) / 5426.1(6) / 2842.92(17)
Z / 8 / 4
Density (gcm-3) / 1.191 / 1.207
μ (mm-1) / 0.076 / 0.079
F (000) / 2096 / 1112
hmin, max / -30, 30 / -14, 14
kmin, max / -19, 19 / -19, 19
lmin, max / -16, 16 / -20, 20
Reflections collected / 10581 / 11146
Independent reflections / 6216 / 8686
R_all, R_obs / 0.1194, 0.0546 / 0.0650, 0.0486
wR2_all, wR2_obs / 0.1331, 0.1155 / 0.1978, 0.1720
min,max (e Å-3) / -0.270, 0.251 / -0.235, 0.344
GOOF / 0.968 / 0.800

Compounds 4a and 4b were crystallized from 1:1 mixture of methanol and chloroform in room temperature by slow evaporation method. The block shaped medium size crystal was mounted on a nylon loop with the help of paraton oil and X-ray analyses were carried out at 110K. The X-ray analysis of compound 4a indicates that the crystal structure belongs to the monoclinic space group P21/c with Z’=2 while 4b has crystallized in triclinic spacegroup P-1 with (Z’=2). There are two symmetry independent molecules are present in the assymetric unit of compound 4a as well as 4b. Figure S13 shows the ORTEP diagram of the compounds 4a and 4b at 50% probability ellipsoids

Fig. S13 Molecular structures (ORTEP diagram drawn at 50% probability ellipsoids at 110 K): Compound 4aP21/c (Z’=2); Compound 4b, P-1(Z’=2). (Only one molecule has been shown in the diagram for clarity)

Table S2 Intermolecular hydrogen bonds in the crystal structures of compounds 4a and 4b

Compound / D−H···A / d(D−H)Å / d(D−A)Å / d(H···A) Å / d(H···A) (deg) / Symmetry
4a / C(30)−H(26)···N(2) / 1.08 / 2.260(1) / 3.32 / 166 / 1-x,1/2+y,1/2-z
C(61)−H(69)···N(4) / 1.08 / 2.340(1) / 3.38 / 161 / -x,1/2+y,1/2-z
4b / C(11)−H(11)···N(4) / 1.08 / 2.440(2) / 3.51 / 170 / 1-x,1-y,1-z
C(51)−H(51)···O(8) / 1.08 / 2.470(1) / 3.48 / 155 / 1-x,1-y,1-z
C(61)−H(61)···O(1) / 1.08 / 2.520(1) / 2.90 / 100 / 1-x,1-y,1-z

Table S3 Pi−Pi interactions in crystal structures of compounds 4a and 4b

Compound / Cg···Cgb / d[Cg ···Cg] (Å) / Symmetry
4a / Cg(6) ···Cg(4) / 3.649(2) / -X,1-Y,1-Z
Cg(2) ···Cg(2) / 3.631(1) / 1-X,-Y,-Z
Cg(3) ···Cg(1) / 4.079(4) / 1-X,-Y,1-Z
4b / Cg(1)Cg(5) / 3.707(2) / X, Y, Z
Cg(3)Cg(4) / 3.519(1) / X, Y, Z

Table S4 C−H ···π interactions in crystal structure of the compounds 4a and 4b

Compound / D−H···A / d(D−H)Å / d(D−A)Å / d(H···A) Å / d(H···A) (deg) / Symmetry
4a / C(5)−H(16)···Cg(1) / 0.90 / 3.869(2) / 2.79 / 167 / 1-X,-Y,-Z
C(20)−H(33)···Cg(3) / 0.89 / 3.683(1) / 2.86 / 141 / X,1/2-Y,1/2+Z
C(52)−H(44)···Cg(6) / 0.88 / 3.600(2) / 2.79 / 140 / X,3/2-Y,1/2+Z
C(35)−H(60)···Cg(4) / 0.86 / 3.652(1) / 2.77 / 142 / -X,1-Y,-Z
4b / C(3−)H(3B) ···Cg(2) / 0.93 / 3.764(2) / 2.87 / 154 / -X,1-Y,2-Z
C(28)−H(28B)···Cg(3) / 0.85 / 3.563(1) / 2.71 / 147 / -X,-Y,1-Z
C(38) −H(38B)···Cg(2) / 0.91 / 3.793(1) / 2.87 / 160 / X,Y,Z

Table S5 Important torsions considered in compounds 4a and 4b

Compound / Torsion (°)
4a
(Z’=2) / M1 / C9−C10−C11−C26 / -40.00 / C15- C14-C13- N1 / 1.18
M2 / C40-C41-C42-C57 / -39.04 / C46-C45-C44- N3 / -0.89
4b
(Z’=2) / M1 / C25-C20-C15-C16 / -35.69 / C9-C10-C13-N1 / -17.45
M2 / C41-C45-C46-C50 / 40.15 / C57-C53-C48-N3 / -22.41

4.PXRD data

Table S6 Powder X-ray diffraction data of compounds 4c and 4f at room temperature

Compound / T(°C) / dobs(Å) / Phase symmetry / Miller indices hkl / dcal (Å) / Lattice parameters
4c / 25 / 16.01
11.66
8.06
4.89 / Colr
c2mm / 200
110
400
halo / 16.00
11.65
8.05 / a = 32.02 Å
b = 12.51 Å
S=400.57 Å2
Vm=881.26Å3
Scol=200.28Å2
4f / 25 / 20.19
15.34
7.80
4.57 / Colr
c2mm / 200
110
510
halo / 20.18
15.32
7.80 / a = 40.38 Å
b = 16.58 Å
S=669.50 Å2
Vm=974.42Å3
Scol=334.75Å2

dobs and dcal are the measured and theoretical diffraction spacings; dcal is deduced from the following mathematical expression: 1/dhk =√(h2/a2+k2/b2); hk are the indexations of the reflections corresponding to the rectangular symmetry, and a and b are the lattice parameters of the Colr phase (a=2d20). For the Colr, S=a×b where S is the lattice area and Scol=S/2 where, Scol is the columnar cross-section. Molecular volume Vm is calculated using the formula Vm=M / λδNA where M is the molecular weight of the compound, NA is the Avogadro number, δ is the volume mass density (≈1g cm-3), and λ(T) is a temperature correction coefficient at the temperature of the experiment (T), λ=VCH2(T0)/VCH2(T), where T0=25 °C, VCH2(T)=26.5616+0.02023T.

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