Quantum Chemical Investigation of Intramolecular Thione-Thiol

SUPPLEMENTARY MATERIAL

Quantum chemical investigation of intramolecular thione-thiol tautomerism of 1,2,4-triazole-3-thione and its disubstituted derivatives

Mehdi D. Davari, Zahra Zolmajd Haghighi, Homayoon Bahrami, Mansour Zahedi*

Department of Chemistry, Faculty of Sciences, Shahid Beheshti University, G.C., Evin, 19839-6313, Tehran, Iran

E-mail: [email protected]

Tel.: 0098-21-22401765

Fax: 0098-21-22401765

*Corresponding author

SM-1 Supplementary Material Contents:

Page SM3-T1 The average errors in bond distances and bond angles of 2,4-dihydro-3H-5-phenyl-4-amino- 1,2,4-triazole-3-thione calculated by different basis sets and B3LYP method. These parameters have been compared to the corresponding X-ray crystallography data in reference no. 40. The measures for dihedral angles were all the same so the average errors were zero and they are not mentioned here.

Pages SM4-SM21, T2-T19 The following tables show the calculated vibrational frequencies (cm-1) and IR intensities (km/mol) of some isomers of 2,4-dihydro-4-(4-halophenyl)-5-(isomeric pyridyl)-3H-1,2,4-triazole-3-thione at B3LYP/6-31G(d,p) level. The numbering system is the same as Fig. 2 in the main manuscript. For thione forms N-H, C-X, and C=S vibrational frequencies while for thiol forms S-H, C-F, and C-S vibrational frequencies have been assigned. The scaling factors have been obtained by correlation of experimental frequencies and calculated frequencies. These scales could be used for prediction of vibrational frequencies of the thiol or thione species where ever there is no experimental frequency for them. As an example, in Tables T7-T9 we could guess the experimental frequencies for thiol form using the calculated scaling factors for thione form in Tables T2-T6.

SM-2 T1

average error basis set bond distances (A°) bond angles (°) 6-31G 0.026 0.177 6-31G(d) 0.014 0.177 6-31G(d,p) 0.005 -0.038 6-31+G(d,p) 0.005 -0.002 6-31++G(d,p) 0.005 -0.002 6-311G(d,p) 0.003 -0.004 6-311+G(d,p) 0.003 0.021 6-311++G(d,p) 0.003 0.021 CC-PVDZ 0.008 -0.078 CC-PVTZ 0.008 -0.004

SM-3 T2- thione-FO2

Calculated Experimental Scaling No. Bond Vibration Intensity Frequency Frequency Factor 78 N-H Stretching 3682 126 3498 0.950 49 Stretching 1181 12 52 Stretching 1266 113 53 Stretching 1284 116 C-Cl 1050 0.823 54 Stretching 1312 14 55 Stretching 1317 4 56 Stretching 1323 7 57 Stretching 1348 9 59 C=S Bending 1420 54 1284 0.900 60 Stretching 1455 3

SM-4 T3- thione-FO1

Calculated Experimental Scaling No. Bond Vibration Intensity Frequency Frequency Factor 78 N-H Stretching 3682 128 3498 0.95 49 Stretching 1197 92 52 Stretching 1246 126 53 C-F Stretching 1305 29 1050 0.839 54 Stretching 1306 28 55 Stretching 1328 10 56 Stretching 1339 19 57 Stretching 1350 12 59 C=S Bending 1366 15 1284 0.900 60 Stretching 1458 39

SM-5 T4- thione-FM1

SM-6 T5- thione-FM2

SM-7 T6- thione-FPa

Calculated Experimental Scaling No. Bond Vibration Intensity Frequency Frequency Factor 78 N-H Stretching 3682 128 3472 0.943 49 Stretching 1180 14 52 Bending 1266 118 53 C-F Bending 1285 116 1065 0.830 54 Bending 1295 4 55 Bending 1317 2 56 Stretching 1347 27 57 Stretching 1357 92 59 C=S Bending 1424 45 1289 0.928 60 Stretching 1453 20

SM-8 T7-thiol-FPa

Calculated Experimental Scaling No. Bond Vibration Intensity Frequency Frequency Factor 70 Stretching 2704 0 0.943 36 S-H 934 18 Bending 37 954 1 52 1284 106 C-F Stretching 50 1179 13 23 637 20 40 988 7 Stretching 43 1022 9 C-S 0.830 44 1038 2 53 1292 4 Bending 54 2704 0

SM-9 T8-thiol-FM1

SM-10 T9- thiol-FM2

SM-11 T10- thione-ClO1

Calculated Experimental Scaling No. Bond Vibration Intensity Frequency Frequency Factor 78 N-H Stretching 3683 127 3462 0.940 36 Stretching 956 2 34 Bending 842 17 31 C-Cl Bending 761 8 735 0.826 29 Bending 746 1 28 Bending 720 11 27 Stretching 714 24 57 Stretching 1337 3 59 C=S Bending 1427 57 1278 0.897 60 Stretching 1443 4

SM-12 T11- thione-ClO2

Calculated Experimental Scaling No. Bond Vibration Intensity Frequency Frequency Factor 78 N-H Stretching 3681 130 3462 0.940 36 Stretching 958 1 34 Bending 845 26 31 Bending 763 18 C-Cl 735 0.820 29 Bending 746 2 28 Bending 723 10 27 Stretching 716 17 57 Stretching 1338 3 59 C=S Bending 1416 84 1278 0.930 60 Stretching 1445 6

SM-13 T12- thione-ClM1

Calculated Experimental Scaling No. Bond Vibration Intensity Frequency Frequency Factor 78 N-H Stretching 3683 129 3467 0.947 36 Stretching 956 2 34 Bending 843 22 31 C-Cl Bending 761 11 730 0.810 29 Bending 726 19 28 Bending 723 21 27 Stretching 719 5 57 Stretching 1354 112 59 C=S Bending 1421 86 1285 0.930 60 Stretching 1445 7

SM-14 T13- thione-ClM2

Calculated Experimental Scaling No. Bond Vibration Intensity Frequency Frequency Factor 78 N-H Stretching 3683 132 3467 0.947 36 Stretching 958 1 34 C- Cl Bending 844 23 31 Bending 761 8 730 0.820 29 Bending 725 18 28 Bending 723 18 27 Stretching 718 8 57 Stretching 1354 113 59 C=S Bending 1412 66 1285 0.930 60 Stretching 1444 7

SM-15 T14- thione-ClPa

Calculated Experimental Scaling No. Bond Vibration Intensity Frequency Frequency Factor 78 N-H Stretching 3681 132 3496 0.941 36 Stretching 957 2 34 Bending 846 33 31 C- Cl Bending 761 6 730 0.812 29 Bending 737 3 28 Bending 718 16 27 Stretching 709 13 57 Stretching 1353 117 59 C=S Bending 1421 72 1284 0.935 60 Stretching 1444 8

SM-16 T15- thione-BrO1

Calculated Experimental Scaling No. Bond Vibration Intensity Frequency Frequency Factor 78 N-H Stretching 3684 128 3460 0.940 36 Stretching 970 3 34 Bending 848 16 31 C-Br Bending 759 10 638 0.826 29 Bending 740 4 28 Bending 728 5 27 Stretching 714 24 57 Stretching 1336 3 59 C=S Bending 1426 60 1278 0.897 60 Stretching 1440 6

SM-17 T16- thione-BrO2

SM-18 T17- thione-BrM1

SM-19 T18- thione-BrM2

SM-20 T19- thione-BrPa