Supporting Information

Supporting Information Tuning of Excited-State Intramolecular Proton Transfer (ESIPT) Fluorescence of Imidazo[1,2-a]pyridine in Rigid Matrices by Substitution Effect Toshiki Mutai,* irotaka Sawatani, Toshihide Shida, ideaki Shono, and Koji Araki* Department of Materials and Environmental Science, Institute of Industrial Science, the University of Tokyo, 4-6-1, Komaba, Meguro-ku, Tokyo 153-8505, Japan. E-mail: araki@iis.u-tokyo.ac.jp, mutai@iis.u-tokyo.ac.jp Contents: Table S1. Calculated energy level of M IPT and LUM IPT, and the lowest transition energy (ΔE) obtained using the CIS-method in the intramolecular hydrogen-transferred (IPT) state of 1 14.... Page S1 Gaussian job files for geometry optimization and energy calculation of the ESIPT state of 1 14. Figure S1 S26. 1 MR (400 Mz) and 13 C MR (100 Mz) spectra of 2 14 in CDCl 3.... S2 S15... S16 S41

Table S1. Calculated energy level of M IPT and LUM IPT, and the lowest transition energy (ΔE) obtained using the CIS-method in the intramolecular hydrogen-transferred (IPT) state of 1-14. M IPT /ev LUM IPT /ev ΔE /ev 1-6.14 0.79 3.58 2-5.73 0.82 3.35 3-5.97 0.82 3.50 4-6.33 0.67 3.61 5-6.37 0.65 3.63 6-6.16 0.72 3.53 7-6.08 0.84 3.59 8-6.29 0.48 3.47 9-6.29 0.48 3.46 10-6.37 0.41 3.46 11-6.47 0.22 3.42 12-6.18 0.85 3.62 13-6.11 0.51 3.38 14-6.10 0.44 3.37 S1

Gaussian job file of PIP (1) %chk=1_ipt_ex_pt.chk # opt cis/6-31g(d) nosymm fchk Density=All FChk=All Pop=Regular 1_ESIPT_ptimization C1-0.00001000 0.00000000 0.00000000 C2-0.60917700-1.19238200-0.36143300 C3-0.02146200-2.44120000-0.01288500 C4 1.09629100-2.51001000 0.76085600 5 1.63018100-1.3134960.28178300 C6 1.14546100-0.06882700 0.78028500 7 2.12320600 0.9004790.09817900 C8 3.18553600 0.2582280.77311300 C9 2.94538100-1.0986180.82310600 C10 4.3042980.03430600 2.27736100 C11 4.16120600 2.49185400 2.40669400 C12 5.31744000 3.22445300 2.89421900 C13 6.47495100 2.56366000 3.23585100 C14 6.5738570.18332600 3.11467400 C15 5.48354000 0.42704400 2.62806400 16 3.10332900 3.07919500 2.11234100 17 1.9757530.8895310.22394600 18-1.52924900-1.18449500-0.95191500 19-0.48205600-3.36074600-0.38790500 2.59843300-3.4443350.03334500 21 3.56493900-1.90509600 2.21201700 22 5.24072800 4.31315700 2.99427800 25 5.59389400-0.66013900 2.53307500 27-0.39876100 0.96576600-0.32594600 28 7.33425100 3.13287600 3.60962600 29 7.49919800 0.66849800 3.39298200 --Link1-- %chk=1_ipt_ex_pt.chk # cis=direct/6-31+g(d) nosymm geom=check Density=CI FChk=All Pop=Regular 1_ESIPT_ptimized_SinglePoint S2

Gaussian job file of 5 -methoxy PIP (2) %chk=2_ipt_ex_pt.chk # opt cis/6-31g(d) nosymm fchk Density=All FChk=All Pop=Regular 2_ESIPT_ptimization C1-0.00001000 0.00000000 0.00000000 C2-0.66703590-1.15852480-0.34158440 C3-0.15772760-2.43541110 0.04954020 C4 0.94434900-2.54824320 0.83559050 5 1.54400220-1.3742099.33747560 C6 1.13763370-0.11530000 0.79806890 7 2.13344940 0.8042068.15743600 C8 3.20498890 0.1173333.75159850 C9 2.87914420-1.2251408.85262870 C10 4.40340000 0.82509150 2.14988050 C11 4.49697270 2.2724159.92472790 C12 5.70146880 2.93394810 2.39603720 C13 6.71939450 2.23106470 2.97605770 C14 6.61166040 0.83655810 3.14461530 C15 5.44598060 0.14260920 2.73438980 16 3.59612790 2.9109701.34500730 17 2.1911590.78797940 0.94560550 18-1.57623210-1.11752100-0.94730160 19-0.67126360-3.33418860-0.30669280 2.38652010-3.5037433.13883200 21 3.45433830-2.05780130 2.25164820 22 5.77679510 4.01998060 2.26771580 23 7.70796630 0.25575200 3.73098660 C24 7.68273710-1.13628540 3.93635710 25 5.36426740-0.94199920 2.88365900 27-0.33699830 0.98069640-0.35097130 28 7.62593480 2.74994270 3.31349760 29 7.60842440-1.69344790 2.99529970 30 6.87586360-1.44237360 4.61235790 31 8.65349610-1.31905260 4.40467820 --Link1-- %chk=2_ipt_ex_pt.chk # cis=direct/6-31+g(d) nosymm geom=check Density=CI FChk=All Pop=Regular 2_ESIPT_ptimized_SinglePoint S3

Gaussian job file of 5 -methyl PIP (3) %chk=3_ipt_ex_pt.chk # opt cis/6-31g(d) nosymm fchk Density=All FChk=All Pop=Regular 3_ESIPT_ptimization C1-0.00001000 0.00000000 0.00000000 C2-1.17622320-0.18960680-0.69706930 C3-1.66143390-1.50962120-0.95969310 C4-1.04390820-2.60522070-0.45131690 5 0.04674720-2.42559140 0.43210060 C6 0.63986850-1.12545180 0.51347160 7 1.93069880-1.3135338.03443200 C8 2.19130400-2.6872054.14276510 C9 1.07399840-3.39300710 0.73724220 C10 3.47656620-3.1601560.62414890 C11 4.47054710-2.19048700 2.10150070 C12 5.71945840-2.73327380 2.61955760 C13 5.95482900-4.07925530 2.61667460 C14 5.00187060-4.98338200 2.12604220 C15 3.76476040-4.5040808.63833400 16 4.27354570-0.96295690 2.06051940 17 2.60259350-0.6208347.31820130 18-1.73064670 0.66451720-1.09476520 19-2.54529860-1.62243680-1.59562190 20-1.35857340-3.63554560-0.64989360 21 0.91465130-4.46626900 0.65904150 22 6.46487530-2.03072450 3.00981280 C23 5.29076700-6.43489200 2.12968610 25 3.02497030-5.2277213.27003280 27 0.43074190 0.99693730 0.13744020 28 6.90406630-4.47105650 3.00365560 29 5.45568480-6.79689080 3.15439820 30 6.20161710-6.6544626.55503360 31 4.47399230-7.0269085.69629950 --Link1-- %chk=3_ipt_ex_pt.chk # cis=direct/6-31+g(d) nosymm geom=check Density=CI FChk=All Pop=Regular 3_ESIPT_ptimized_SinglePoint S4

Gaussian job file of 5 -chloro PIP (4) %chk=4_ipt_ex_pt.chk # opt cis/6-31g(d) nosymm fchk Density=All FChk=All Pop=Regular 4_ESIPT_ptimization C1-0.00001000 0.00000000 0.00000000 C2-0.57218570-1.19153480-0.42181810 C3 0.05877080-2.43574400-0.14509740 C4 1.18079200-2.51120110 0.62260470 5 1.67865870-1.3262844.20971440 C6 1.15624940-0.07416510 0.76559410 7 2.09441590 0.9008528.14822410 C8 3.20562220 0.2652196.73702320 C9 3.00073040-1.0990489.73166620 C10 4.3277995.04416850 2.22966570 C11 4.23698990 2.51298370 2.24587670 C12 5.38919070 3.24116620 2.76825040 C13 6.49836630 2.57773110 3.21174430 C14 6.5534532.18082030 3.17238590 C15 5.46391500 0.42118870 2.67950840 16 3.23458340 3.1181015.83272390 17 1.9969737.9018793.15048660 18-1.49638400-1.18157200-1.00579980 19-0.37152080-3.34798650-0.57084850 2.71304730-3.44227970 0.84367280 21 3.64889040-1.90615060 2.06870520 22 5.33837870 4.33577870 2.79820050 Cl23 7.91015870 0.38580260 3.71240060 25 5.54794320-0.67293940 2.66810620 27-0.43349650 0.96817580-0.26895810 28 7.35961690 3.13259340 3.60438220 --Link1-- %chk=4_ipt_ex_pt.chk # cis=direct/6-31+g(d) nosymm geom=check Density=CI FChk=All Pop=Regular 4_ESIPT_ptimized_SinglePoint S5

Gaussian job file of 5 -bromo PIP (5) %chk=5_ipt_ex_pt.chk # opt cis/6-31g(d) nosymm fchk Density=All FChk=All Pop=Regular 5_ESIPT_ptimization C1-0.00001000 0.00000000 0.00000000 C2-0.67553730-1.16101450-0.36404090 C3-0.08808720-2.42959480-0.12606150 C4 1.14131060-2.56911710 0.45870850 5 1.83710030-1.38854300 0.83368880 C6 1.24333750-0.12107910 0.59163410 7 2.15380440 0.8582943.05694290 C8 3.31059130 0.2360040.60019530 C9 3.14788520-1.1489895.46806080 C10 4.3889072.01062080 2.14346460 C11 4.32459550 2.48196170 2.16869360 C12 5.40847590 3.25327100 2.69578270 C13 6.56364830 2.60875700 3.22644110 C14 6.5949144.22018550 3.16392260 C15 5.58817420 0.42149260 2.66914920 16 3.29928210 3.0692433.71470620 17 2.0322480.8485971.05773420 18-1.66230930-1.09608820-0.83538080 19-0.65248410-3.31992180-0.42702390 2.57431120-3.55143380 0.63327170 21 3.84037650-1.9117635.77380150 22 5.34093680 4.33313280 2.71648030 Br23 8.08178140 0.38876190 3.83675070 25 5.70434070-0.65237710 2.66866100 27-0.46193670 0.97378540-0.18835910 28 7.35875140 3.20950380 3.62431110 --Link1-- %chk=5_ipt_ex_pt.chk # cis=direct/6-31+g(d) nosymm geom=check Density=CI FChk=All Pop=Regular 5_ESIPT_ptimized_SinglePoint S6

Gaussian job file of 5 -fluoro PIP (6) %chk=6_ipt_ex_pt.chk # opt cis/6-31g(d) nosymm fchk Density=All FChk=All Pop=Regular 6_ESIPT_ptimization C1-0.00001000 0.00000000 0.00000000 C2-0.62828930-1.19963780-0.34763180 C3-0.00647220-2.44162240-0.09975690 C4 1.22559770-2.52747450 0.49024020 5 1.86435050-1.32742740 0.86100080 C6 1.24456850-0.07924040 0.59961370 7 2.13857660 0.8964651.07438900 C8 3.29454360 0.2585447.57871600 C9 3.14241740-1.1079716.45839390 C10 4.3966120.03517930 2.12063440 C11 4.30921380 2.50605710 2.12806540 C12 5.42324610 3.23475670 2.71403000 C13 6.52254190 2.57761710 3.21180950 C14 6.5758638.18163250 3.16385090 C15 5.50564590 0.40666350 2.62152290 16 3.33120330 3.1095943.65366990 17 2.0645649.8995188.03345140 18-1.61395790-1.17680480-0.81935530 19-0.52616190-3.36158400-0.38774200 2.74827960-3.46598100 0.70008870 21 3.81318110-1.9174084.74448010 22 5.36818100 4.32920640 2.74741200 F23 7.64922840 0.53922270 3.64002610 25 5.58764050-0.68747010 2.61770180 27-0.47424680 0.96578370-0.19572210 28 7.35735110 3.14207540 3.64565760 --Link1-- %chk=6_ipt_ex_pt.chk # cis=direct/6-31+g(d) nosymm geom=check Density=CI FChk=All Pop=Regular 6_ESIPT_ptimized_SinglePoint S7

Gaussian job file of 6-methyl PIP (7) %chk=7_ipt_ex_pt.chk # opt cis/6-31g(d) nosymm fchk Density=All FChk=All Pop=Regular 7_ESIPT_ptimization C1-0.00001000 0.00000000 0.00000000 C2-0.97047800-0.88356600-0.44543200 C3-0.82590300-2.29353400-0.24614600 C4 0.23958700-2.79965800 0.43910000 5 1.15919900-1.9043580.01124400 C6 1.07639300-0.51729800 0.70377100 7 2.30969300 0.0615950.10459300 C8 3.09674300-0.9628270.68704300 C9 2.45107500-2.1763450.56251800 C10 4.37354100-0.63501600 2.29499700 C11 5.35064600-1.58253800 2.44840600 C12 6.59786300-1.25000300 3.03331800 C13 6.85506400 0.04623300 3.44919400 C14 5.9074620.03990600 3.31194500 C15 4.60765100 0.74719000 2.73830200 16 3.7328710.62766600 2.62811300 17 2.4230670.0028690.45196200 18-1.84840400-0.51480600-0.98410100 20 0.41073400-3.87086400 0.59733200 21 2.78514400-3.1755660.83887500 22 7.35565500-2.03128300 3.15009600 24-0.0751810.07384500-0.19773100 25 7.82744300 0.28655100 3.89539400 26 6.11336800 2.06213300 3.64904700 C27-1.86818800-3.19593000-0.80102700 29 5.17871900-2.61361200 2.11655900 30-1.52268500-4.23533900-0.87279900 31-2.76054700-3.18496600-0.16026100 32-2.17762800-2.87830900-1.80543800 --Link1-- %chk=7_ipt_ex_pt.chk # cis=direct/6-31+g(d) nosymm geom=check Density=CI FChk=All Pop=Regular 7_ESIPT_ptimized_SinglePoint S8

Gaussian job file of 6-chloro PIP (8) %chk=8_ipt_ex_pt.chk # opt cis/6-31g(d) nosymm fchk Density=All FChk=All Pop=Regular 8_ESIPT_ptimization C1-0.00001000 0.00000000 0.00000000 C2-1.09705100-0.67942700-0.53225400 C3-1.10261500-2.09706500-0.57508500 C4-0.06452100-2.85236300-0.11435400 5 1.04788200-2.17364600 0.41592600 C6 1.05960900-0.75516000 0.47018800 7 2.29273000-0.4077470.06176300 C8 3.00755600-1.5798970.36163100 C9 2.25516000-2.68035600 0.97454400 C10 4.31968700-1.5121860.97812900 C11 5.01740700-2.65344100 2.27085100 C12 6.30191600-2.59180500 2.87333900 C13 6.87636900-1.37093700 3.17770600 C14 6.21761000-0.18841900 2.90420500 C15 4.90359300-0.19657900 2.28947200 16 4.30511100 0.86749500 2.04040800 17 2.66364100 0.5070440.26084500 18-1.95969900-0.12929900-0.91859800 20-0.04387400-3.94740200-0.13438200 21 2.48067400-3.7429170.05016000 22 6.82976400-3.52543700 3.09279200 24 0.0203160.09335500 0.04354800 25 7.86892900-1.34045800 3.64272100 26 6.67608500 0.77714800 3.14660400 Cl27-2.46233600-2.86614100-1.22899100 29 4.59229400-3.63843000 2.04288300 --Link1-- %chk=8_ipt_ex_pt.chk # cis=direct/6-31+g(d) nosymm geom=check Density=CI FChk=All Pop=Regular 8_ESIPT_ptimized_SinglePoint S9

Gaussian job file of 6-bromo PIP (9) %chk=9_ipt_ex_pt.chk # opt cis/6-31g(d) nosymm fchk Density=All FChk=All Pop=Regular 9_ESIPT_ptimization C1-0.00001000 0.00000000 0.00000000 C2-1.09868400-0.67889100-0.53432700 C3-1.07606300-2.08056200-0.56531200 C4-0.06144400-2.86151400-0.11346200 5 1.04786000-2.18197200 0.42664100 C6 1.05765400-0.76063100 0.47273300 7 2.28706100-0.4105850.05876800 C8 3.00963500-1.5819430.36129300 C9 2.26410500-2.68375900 0.97992300 C10 4.32182600-1.5023560.97711300 C11 5.02660600-2.63958100 2.27389500 C12 6.30841000-2.56894400 2.87540600 C13 6.87597500-1.34218000 3.17643100 C14 6.21094100-0.16591000 2.89944400 C15 4.89714000-0.18336000 2.28417200 16 4.29234300 0.87678800 2.03146300 17 2.65693800 0.5055470.25708500 18-1.96766500-0.14342500-0.92522900 19-0.05836100-3.95591200-0.14462500 20 2.49275000-3.7455840.05516700 21 6.84278100-3.49815900 3.09840200 22 0.0239570.09304300 0.04337700 23 7.86808500-1.30531800 3.64155800 24 6.66296800 0.80362000 3.13902800 Br25-2.57488800-2.93002900-1.29201500 26 4.60606900-3.62738100 2.04873400 --Link1-- %chk=9_ipt_ex_pt.chk # cis=direct/6-31+g(d) nosymm geom=check Density=CI FChk=All Pop=Regular 9_ESIPT_ptimized_SinglePoint S10

Gaussian job file of 6-trifluoromethyl PIP (10) %chk=10_ipt_ex_pt.chk # opt cis/6-31g(d) nosymm fchk Density=All FChk=All Pop=Regular 10_ESIPT_ptimization C1-0.00001000 0.00000000 0.00000000 C2-0.97047800-0.88356600-0.44543200 C3-0.82590300-2.29353400-0.24614600 C4 0.23958700-2.79965800 0.43910000 5 1.15919900-1.9043580.01124400 C6 1.07639300-0.51729800 0.70377100 7 2.30969300 0.0615950.10459300 C8 3.09674300-0.9628270.68704300 C9 2.45107500-2.1763450.56251800 C10 4.37354100-0.63501600 2.29499700 C11 5.35064600-1.58253800 2.44840600 C12 6.59786300-1.25000300 3.03331800 C13 6.85506400 0.04623300 3.44919400 C14 5.9074620.03990600 3.31194500 C15 4.60765100 0.74719000 2.73830200 16 3.7328710.62766600 2.62811300 17 2.4230670.0028690.45196200 18-1.84840400-0.51480600-0.98410100 20 0.41073400-3.87086400 0.59733200 21 2.78514400-3.1755660.83887500 22 7.35565500-2.03128300 3.15009600 24-0.0751810.07384500-0.19773100 25 7.82744300 0.28655100 3.89539400 26 6.11336800 2.06213300 3.64904700 C27-1.86818800-3.19593000-0.80102700 29 5.17871900-2.61361200 2.11655900 F30-1.52268500-4.23533900-0.87279900 F31-2.76054700-3.18496600-0.16026100 F32-2.17762800-2.87830900-1.80543800 --Link1-- %chk=10_ipt_ex_pt.chk # cis=direct/6-31+g(d) nosymm geom=check Density=CI FChk=All Pop=Regular 10_ESIPT_ptimized_SinglePoint S11

Gaussian job file of 6-cyano PIP (11) %chk=11_ipt_ex_pt.chk # opt cis/6-31g(d) nosymm fchk Density=All FChk=All Pop=Regular 11_ESIPT_ptimization C1-0.00001000 0.00000000 0.00000000 C2-0.93025100-0.86747400-0.47656700 C3-0.68853500-2.29840900-0.41103500 C4 0.49641300-2.76998500 0.14147400 5 1.45022300-1.89630600 0.62839700 C6 1.20981700-0.49446000 0.56121100 7 2.35870000 0.1514690.12465600 C8 3.29128200-0.8135530.55417100 C9 2.75785200-2.0550250.25136500 C10 4.60380200-0.53651400 2.21067900 C11 5.49774000-1.51882300 2.58164500 C12 6.74953100-1.25870000 3.19476300 C13 7.16008900 0.06142000 3.43436100 C14 6.3368600.09254400 3.09785600 C15 4.99222200 0.86368500 2.53618200 16 4.2313310.81664000 2.39350600 17 2.4271610.1333600.21040700 18-1.86581200-0.49263800-0.91477000 20 0.63798800-3.85685300 0.17216900 21 3.26961700-2.9933310.46554700 22 7.41881600-2.08510600 3.48933800 24-0.1962220.07655700-0.05875200 25 8.13262900 0.27354300 3.90259200 26 6.66654800 2.12417900 3.27196400 C27-1.67255200-3.19601600-0.91539900 28-2.48263200-3.92396100-1.33014000 29 5.29562600-2.58787700 2.44213800 --Link1-- %chk=11_ipt_ex_pt.chk # cis=direct/6-31+g(d) nosymm geom=check Density=CI FChk=All Pop=Regular 11_ESIPT_ptimized_SinglePoint S12

Gaussian job file of 4 -methoxy PIP (12) %chk=12_ipt_ex_pt.chk # opt cis/6-31g(d) nosymm fchk Density=All FChk=All Pop=Regular 12_ESIPT_ptimization C1-0.00001000 0.00000000 0.00000000 C2-0.53271530-1.20439650-0.41601950 C3 0.12181060-2.43632920-0.09966050 C4 1.21163220-2.47141310 0.70610410 5 1.64723700-1.2707535.31910080 C6 1.12618820-0.03544290 0.81689110 7 2.05824580 0.9621865.16099760 C8 3.17050470 0.3608133.76888340 C9 2.98082540-1.0053716.81713080 C10 4.2848126.16891420 2.23322320 C11 4.14011620 2.63124690 2.30138420 C12 5.27167830 3.38968540 2.81670860 C13 6.42007680 2.74129460 3.19675420 C14 6.5436367.33359260 3.09544830 C15 5.46854690 0.57752500 2.61490050 16 3.10462800 3.2074189.92937720 17 1.9285906.9588186.17213720 18-1.43772770-1.22986380-1.02900200 19-0.27332810-3.36116080-0.53225620 2.76351830-3.38449880 0.95356710 21 3.64403970-1.79263110 2.16939850 22 5.16030080 4.47910230 2.88624590 23 7.55277630 3.34641010 3.70091090 C24 7.52218320 4.74207840 3.87785410 25 5.57852780-0.51276000 2.54916400 27-0.43613380 0.95590770-0.30697950 29 7.47286760 0.83569310 3.39576940 30 6.73429280 5.05595460 4.57231870 31 7.41219100 5.27599600 2.92702180 32 8.50628880 4.94164600 4.31029380 --Link1-- %chk=12_ipt_ex_pt.chk # cis=direct/6-31+g(d) nosymm geom=check Density=CI FChk=All Pop=Regular 12_ESIPT_ptimized_SinglePoint S13

Gaussian job file of 6-chloro-5 -methyl PIP (13) %chk=13_ipt_ex_pt.chk # opt cis/6-31g(d) nosymm fchk Density=All FChk=All Pop=Regular 13_ESIPT_ptimization C1-0.00001000 0.00000000 0.00000000 C2-1.18978870-0.18246590-0.67479890 C3-1.69481720-1.51060700-0.88596380 C4-1.09027580-2.60729190-0.37369460 5 0.02871110-2.42107720 0.46883450 C6 0.62982550-1.12325630 0.52915020 7 1.92477070-1.3156054.05496710 C8 2.16333440-2.6820018.20321280 C9 1.03207300-3.38777650 0.80620920 C10 3.43515830-3.1629358.70815850 C11 4.43440730-2.19650620 2.18113720 C12 5.67349170-2.74363250 2.71491220 C13 5.89354600-4.09356090 2.73674340 C14 4.93711170-4.99450460 2.25400440 C15 3.70711470-4.5088073.74712160 16 4.24600990-0.96762790 2.12509410 17 2.59482880-0.6227645.34366120 18-1.74728350 0.66286860-1.08813650 Cl19-3.09299700-1.67114680-1.83015960 20-1.44068600-3.63261990-0.53987090 21 0.86387480-4.46181030 0.75684330 22 6.42564690-2.04403100 3.09787320 C23 5.21181320-6.44831340 2.27883340 25 2.96289760-5.2306886.38438570 27 0.44696170 0.99343150 0.11046570 28 6.83563130-4.48860250 3.13781770 29 5.36974270-6.79836520 3.30886570 30 6.12328930-6.6823739.71084810 31 4.39176730-7.0387736.84943200 --Link1-- %chk=13_ipt_ex_pt.chk # cis=direct/6-31+g(d) nosymm geom=check Density=CI FChk=All Pop=Regular 13_ESIPT_ptimized_SinglePoint S14

Gaussian job file of 5 -methyl-6-trifluoromethyl PIP (14) %chk=14_ipt_ex_pt.chk # opt cis/6-31g(d) nosymm fchk Density=All FChk=All Pop=Regular 14_ESIPT_ptimization C1 0.26872100-0.21172300-0.46611400 C2-0.66152000-1.07919700-0.94268100 C3-0.41980400-2.51013200-0.87714900 C4 0.76514400-2.98170800-0.32464000 5 1.71895400-2.10802900 0.16228300 C6 1.47854800-0.70618300 0.09509700 7 2.62743100-0.06025400 0.65854200 C8 3.56001300-1.0252760.08805700 C9 3.02658300-2.26674800 0.78525100 C10 4.87253300-0.7482370.74456500 C11 5.76647100-1.73054600 2.11553100 C12 7.01826200-1.47042300 2.72864900 C13 7.42882000-0.15030300 2.96824700 C14 6.60559100 0.88082100 2.63174200 C15 5.26095300 0.65196200 2.07006800 16 4.5000620.6049170.92739200 17 2.75158300 0.94911800 0.73700000 18-1.58873600-0.70190600-1.37398400 F19-1.89730700-3.04870700-2.78725300 20 0.94471800-4.05565100-0.27465500 21 3.51307600-3.22177000 0.98363400 C22 7.68754700-2.29682900 3.02322400 F23-0.91442500-4.85606200-1.48814700 24 0.08828300 0.86218500-0.51370200 25 8.40031800 0.04852200 3.42075300 26 6.9498880.90409700 2.78162900 C27-1.48382300-3.48071600-1.42251900 F28-2.66920900-3.47647600-0.51977700 29 5.49454500-2.7689490.92612500 30 8.72498600-1.98184600 2.91094800 31 7.49936900-3.16130600 2.38653900 32 7.49936900-2.56366500 4.06317000 --Link1-- %chk=14_ipt_ex_pt.chk # cis=direct/6-31+g(d) nosymm geom=check Density=CI FChk=All Pop=Regular 14_ESIPT_ptimized_SinglePoint S15

2 C 3 5 -Methoxy PIP (2) Figure S1. 1 MR spectrum (CDCl 3, 400 Mz) of 2.

C 3 5 -Methoxy PIP (2) Figure S2. 13 C MR spectrum (CDCl 3, 100 Mz) of 2.

C 3 5 -Methyl PIP (3) Figure S3. 1 MR spectrum (CDCl 3, 400 Mz) of 3.

C 3 5 -Methyl PIP (3) Figure S4. 13 C MR spectrum (CDCl 3, 100 Mz) of 3.

2 Cl 5 -Chloro PIP (4) Figure S5. 1 MR spectrum (CDCl 3, 400 Mz) of 4.

Cl 5 -Chloro PIP (4) Figure S6. 13 C MR spectrum (CDCl 3, 100 Mz) of 4.

Br 5 -Bromo PIP (5) Figure S7. 1 MR spectrum (CDCl 3, 400 Mz) of 5.

Br 5 -Bromo PIP (5) Figure S8. 13 C MR spectrum (CDCl 3, 100 Mz) of 5.

2 F 5 -Fluoro PIP (6) Figure S9. 1 MR spectrum (CDCl 3, 400 Mz) of 6.

F 5 -Fluoro PIP (6) Figure S10. 13 C MR spectrum (CDCl 3, 100 Mz) of 6.

2 C 3 6-Methyl PIP (7) Figure S11. 1 MR spectrum (CDCl 3, 400 Mz) of 7.

C 3 6-Methyl PIP (7) Figure S12. 13 C MR spectrum (CDCl 3, 100 Mz) of 7.

2 Cl 6-Chloro PIP (8) Figure S13. 1 MR spectrum (CDCl 3, 400 Mz) of 8.

Cl 6-Chloro PIP (8) Figure S14. 13 C MR spectrum (CDCl 3, 100 Mz) of 8.

2 Br 6-Bromo PIP (9) Figure S15. 1 MR spectrum (CDCl 3, 400 Mz) of 9.

Br 6-Bromo PIP (9) Figure S16. 13 C MR spectrum (CDCl 3, 100 Mz) of 9.

2 CF 3 6-Trifluoromethyl PIP (10) Figure S17. 1 MR spectrum (CDCl 3, 400 Mz) of 10.

CF 3 6-Trifluoromethyl PIP (10) Figure S18. 13 C MR spectrum (CDCl 3, 100 Mz) of 10.

2 C 6-Cyano PIP (11) Figure S19. 1 MR spectrum (CDCl 3, 400 Mz) of 11.

C 6-Cyano PIP (11) Figure S20. 13 C MR spectrum (CDCl 3, 100 Mz) of 11.

2 C 3 4 -Methoxy PIP (12) Figure S21. 1 MR spectrum (CDCl 3, 400 Mz) of 12.

C 3 4 -Methoxy PIP (12) Figure S22. 13 C MR spectrum (CDCl 3, 100 Mz) of 12.

2 Cl C 3 5 -Methyl-6-chloro PIP (13) Figure S23. 1 MR spectrum (CDCl 3, 400 Mz) of 13.

Cl C 3 5 -Methyl-6-chloro PIP (13) Figure S24. 13 C MR spectrum (CDCl 3, 100 Mz) of 13.

2 CF 3 C 3 5 -Methyl-6-trifluoromethyl PIP (14) Figure S25. 1 MR spectrum (CDCl 3, 400 Mz) of 14.

CF 3 C 3 5 -Methyl-6-trifluoromethyl PIP (14) Figure S26. 13 C MR spectrum (CDCl 3, 100 Mz) of 14.