Copyright The Royal Society of Chemistry, 1998 Synthesis and Characterization of the Negative Ion of Non-Kekulé Benzene Brian T. Hill and Robert R. Squires* Department of Chemistry Purdue University West Lafayette, IN 47907 submitted to Journal of the Chemical Society, Perkin Transactions 2 Listings of optimized geometries (in GAUSSIAN archive format) and harmonic vibrational frequencies obtained from B3LYP/6-31+G* calculations for compounds 1, 2, 3, 4, 5, 7, 8, 9, and 10 1. 2,4-dimethylenecyclobutane-1,3-diyl, 3-B2u (D2h) \1\GINC-FLO\Freq\UB3LYP\6-31+G(d)\C6H6(3)\BRIAN\26-Feb-1997\0\\#N BEC KE3LYP/6-31+G* GEOM=CHECK GUESS=READ FREQ=NORAMAN SCF=(DIRECT,TIGHT)\\ COMMENT: bismethylenecyclobutane biradical b3lyp/6-31+g* 3D2h frequenc y\\0,3\C,1.0391340013,0.,0.\C,-1.0391340013,0.,0.\C,0.,1.0270643249,0. \C,0.,-1.0270643249,0.\C,2.4055406773,0.,0.\C,-2.4055406773,0.,0.\H,0. ,2.1110089408,0.\H,0.,-2.1110089408,0.\H,2.9694369186,-0.9282870931,0. \H,2.9694369186,0.9282870931,0.\H,-2.9694369186,0.9282870931,0.\H,-2.9 694369186,-0.9282870931,0.\\Version=IBM-RS6000-G94RevD.2\State=3-B2U\H F=-232.1058697\S2=2.058\S2-1=0.\S2A=2.001\RMSD=6.838e-09\RMSF=4.944e-0 5\Dipole=0.,0.,0.\DipoleDeriv=0., Frequencies -- 145.2552 271.2695 411.2928 Frequencies -- 445.3814 472.3188 476.9058 Frequencies -- 570.3025 641.1206 655.4983 Frequencies -- 692.5190 816.9933 822.7912 Frequencies -- 827.9337 894.0060 927.4379 Frequencies -- 1080.8348 1166.7889 1187.9154 Frequencies -- 1187.9369 1287.1326 1397.0992 Frequencies -- 1465.3355 1520.2512 1662.6975 Frequencies -- 3166.3720 3167.7001 3239.0256 Frequencies -- 3241.4650 3253.3086 3253.3581 2. 2,4-dimethylenecyclobutane-1,3-diyl radical anion, 2-B3g (D2h) \1\GINC-FLO\Freq\UB3LYP\6-31+G(d)\C6H6(1-,2)\BRIAN\29-Aug-1997\0\\#N GEOM=ALLCHECK GUESS=READ UB3LYP/6-31+G(D) FREQ\\COMMENT: bismethylenec yclobutane dirad anion b3lyp/6-31+g* 2D2h\\-1,2\C,0.,0.,-1.0594639149\ C,0.,0.,1.0594639149\C,0.,1.0082433273,0.\C,0.,-1.0082433273,0.\C,0.,0 .,-2.4323324802\C,0.,0.,2.4323324802\H,0.,2.0970328288,0.\H,0.,-2.0970 328288,0.\H,0.,-0.9288942739,-2.9999904807\H,0.,0.9288942739,-2.999990 4807\H,0.,0.9288942739,2.9999904807\H,0.,-0.9288942739,2.9999904807\\V ersion=IBM-RS6000-G94RevD.2\State=2-B3G\HF=-232.1433876\S2=0.767\S2-1= 0.\S2A=0.75\RMSD=4.010e-09\RMSF=7.842e-05\Dipole=0.,0.,0.\ Frequencies -- 144.4193 255.9965 347.5500 Frequencies -- 398.7918 418.4381 519.3911 Frequencies -- 534.5105 572.4833 585.3690 Frequencies -- 609.6456 649.6534 679.8587 Frequencies -- 849.5365 907.6864 910.2371 Frequencies -- 1058.8313 1165.6621 1199.9272 Frequencies -- 1200.6536 1210.2433 1449.6773 Frequencies -- 1460.5011 1585.8883 1655.3544 Frequencies -- 3126.4311 3127.0466 3162.0223 Frequencies -- 3169.2367 3193.7595 3193.7755 3. 1,3-bismethylenecyclobutane, 1-A1 (C2v) 1\1\GINC-FLO\Freq\RB3LYP\6-31+G(d)\C6H8\BRIAN\20-Feb-1997\0\\#N BECKE3 LYP/6-31+G* GEOM=CHECK GUESS=READ FREQ=NORAMAN\\COMMENT: bismethylenec yclobutane b3lyp/6-31+g* freq calc\\0,1\C,1.061124426,0.,0.0000329805\ C,-1.061124426,0.,0.0000329805\C,0.,-1.1032237973,-0.00006029\C,0.,1.1 032237973,-0.00006029\C,-2.3917941544,0.,0.0000255751\C,2.3917941544,0 .,0.0000255751\H,0.,-1.7490328663,0.8886276572\H,0.,-1.7487361684,-0.8 889599796\H,0.,1.7490328663,0.8886276572\H,0.,1.7487361684,-0.88895997 96\H,-2.9618824369,-0.9268707771,0.0001713643\H,-2.9618824369,0.926870 7771,0.0001713643\H,2.9618824369,-0.9268707771,0.0001713643\H,2.961882 4369,0.9268707771,0.0001713643\\Version=IBM-RS6000-G94RevD.2\State=1-A 1\HF=-233.3864873\RMSD=3.526e-09\RMSF=1.520e-05\Dipole=0.,0., Frequencies -- 44.9802 282.5265 363.7411 Frequencies -- 407.2964 417.8520 597.0152 Frequencies -- 609.3802 686.4658 777.5718 Frequencies -- 894.2777 908.0229 908.1844 Frequencies -- 909.0084 911.8614 931.7778 Frequencies -- 1043.8254 1071.4662 1178.9985 Frequencies -- 1183.9241 1236.8464 1242.0685 Frequencies -- 1264.5719 1456.0313 1458.2826 Frequencies -- 1460.2508 1481.4593 1728.4721 Frequencies -- 1779.6451 3031.1589 3036.4262 Frequencies -- 3068.0999 3071.0979 3147.1224 Frequencies -- 3147.4623 3222.1230 3222.2976 4. 1,3-dimethylenecyclobutan-2-ylidene carbene anion, 2-A' (near 2-B1, C2v) 1\1\GINC-FLO\Freq\UB3LYP\6-31+G(d)\C6H6(1-,2)\BOB\16-Aug-1997\0\\#N B3 LYP/6-31+G* FREQ=HPM GUESS=READ GEOM=CHECK SCF=DIRECT\\comment: dimeth ylenecyclobutylidene carbene anion Cs B3LYP/6-31+G* freqs\\-1,2\C,-0.0 178240619,0.,-1.1596278558\C,-0.0016511457,1.0125574894,-0.1020149053\ C,-0.0016511457,-1.0125574894,-0.1020149053\C,0.0156413207,0.,1.050957 6878\H,0.9178326394,0.,1.6910201706\H,-0.8669065526,0.,1.717814354\C,- 0.0011574062,2.3796628725,-0.0941819138\C,-0.0011574062,-2.3796628725, -0.0941819138\H,-0.0148884126,2.9349666203,-1.031913383\H,-0.014888412 6,-2.9349666203,-1.031913383\H,0.0128249042,2.9580464027,0.8306875393\ H,0.0128249042,-2.9580464027,0.8306875393\\Version=IBM-RS6000-G94RevD. 2\State=2-A'\HF=-232.1218215\S2=0.778\S2-1=0.\S2A=0.75\RMSD=2.863e-09\ RMSF=2.961e-05\Dipole=0.0284379,0.,1.8544408\DipoleDeriv=0.,0., Frequencies -- 68.0855 275.8672 417.0639 Frequencies -- 430.1054 473.7589 591.5034 Frequencies -- 606.2781 624.2821 730.2484 Frequencies -- 730.5792 786.5869 888.1491 Frequencies -- 926.5078 959.0516 982.7634 Frequencies -- 1080.3126 1165.2124 1198.4422 Frequencies -- 1276.6375 1347.7384 1419.3338 Frequencies -- 1482.8298 1521.3926 1597.9596 Frequencies -- 2929.8634 2957.7548 3108.4477 Frequencies -- 3109.8830 3184.5356 3184.8038 5. 1,3-bismethylenecyclobutane vinylidene carbene anion, 2-B2 (C2v) 1\1\GINC-FLO\Freq\UB3LYP\6-31+G(d)\C6H6(1-,2)\BOB\20-Aug-1997\0\\#N B3 LYP/6-31+G* GEOM=CHECK GUESS=READ FREQ=HPM SCF=DIRECT\\comment: dimeth ylenecyclobutane vinylidene carbene anion C2v\\-1,2\C,0.,0.,-2.5686179 944\C,0.,0.,-1.2380111131\C,0.,1.1064987011,-0.1270528501\C,0.,-1.1064 987011,-0.1270528501\C,0.,0.,0.9233887922\C,0.,0.,2.2609086511\H,0.,0. 9271024355,2.8357470422\H,0.,-0.9271024355,2.8357470422\H,-0.889677447 9,1.7566283936,-0.1032174747\H,0.8896774479,1.7566283936,-0.1032174747 \H,0.8896774479,-1.7566283936,-0.1032174747\H,-0.8896774479,-1.7566283 936,-0.1032174747\\Version=IBM-RS6000-G94RevD.2\State=2-B2\HF=-232.092 8001\S2=0.757\S2-1=0.\S2A=0.75\RMSD=4.732e-10\RMSF=7.175e-05\Dipole=0. ,0.,3.695911\DipoleDeriv=0.,0., Frequencies -- 37.6466 293.0054 316.4679 Frequencies -- 408.0779 426.2140 593.2028 Frequencies -- 635.7810 740.5397 777.8277 Frequencies -- 849.6965 857.7734 902.9405 Frequencies -- 916.2281 1007.0231 1027.6891 Frequencies -- 1135.3889 1186.8347 1198.2102 Frequencies -- 1231.8104 1444.6479 1457.9086 Frequencies -- 1478.2468 1587.2790 1719.8157 Frequencies -- 2974.4459 2980.7573 3002.1996 Frequencies -- 3003.7469 3107.3630 3170.8414 7. 1,3-bismethylenecyclobutane-2-yl anion, 1-A1 (C2v) 1\1\GINC-FLO\Freq\RB3LYP\6-31+G(d)\C6H7(1-)\BRIAN\21-Feb-1997\0\\#N BE CKE3LYP/6-31+G* GEOM=CHECK GUESS=READ FREQ=NORAMAN\\COMMENT: bismethyl enecyclobutane anion b3lyp/6-31+g* freq calc\\-1,1\C,1.0511436138,-0.0 837598695,0.0054320745\C,-1.0511436138,-0.0837598695,0.0054320745\C,0. ,-1.0462523983,0.0667480048\C,0.,1.0415971428,-0.0660777951\C,-2.42018 40521,-0.0200013172,0.0010226423\C,2.4201840521,-0.0200013172,0.001022 6423\H,0.,-2.1344350207,0.1359918786\H,0.,1.7401878679,0.7862874963\H, 0.,1.6265715835,-1.0000495952\H,-3.0390685826,-0.9154849999,0.05717819 08\H,-2.9382979632,0.9358556713,-0.0590320105\H,3.0390685826,-0.915484 9999,0.0571781908\H,2.9382979632,0.9358556713,-0.0590320105\\Version=I BM-RS6000-G94RevD.2\State=1-A'\HF=-232.7951695\RMSD=6.516e-09\RMSF=1.2 29e-05\Dipole=0.,0.2925147,-0.0181978\DipoleDeriv=0.,0., Frequencies -- 125.6933 273.7765 414.0250 Frequencies -- 468.7257 503.2021 539.4909 Frequencies -- 555.6736 583.4515 633.0161 Frequencies -- 638.9114 705.3348 789.1971 Frequencies -- 911.3667 956.2218 1017.2880 Frequencies -- 1020.3071 1087.3761 1185.6296 Frequencies -- 1198.2318 1248.6325 1309.1246 Frequencies -- 1448.3709 1457.5495 1489.9453 Frequencies -- 1579.0703 1666.9577 2984.6074 Frequencies -- 3015.4142 3117.3209 3117.9675 Frequencies -- 3140.8103 3184.4579 3184.4769 8. 3-methylene-1-methylcyclobutene, 1-A' (C1 near Cs) 1\1\GINC-FLO\Freq\RB3LYP\6-31+G(d)\C6H8\BOB\18-Sep-1997\0\\#N B3LYP/6- 31+G* GUESS=READ GEOM=CHECK FREQ=HPM SCF=DIRECT\\comment: B3LYP/6-31+G * 3-methylene-1-methylcyclobutene C1\\0,1\C,0.0174243518,-0.016168996, -2.4696094501\C,-0.0020177663,-0.0091322423,-1.1327955145\H,0.94056273 47,0.1360196932,-3.0233141912\H,-0.8882117776,-0.1741795846,-3.0509167 135\C,-1.0031393089,-0.1704782475,-0.0695510953\C,1.0743230468,0.18187 4366,-0.0428439961\C,-0.0969838645,-0.0092859503,0.9269494393\H,-2.075 1955615,-0.3522656314,-0.0825896865\H,1.5531751928,1.1701226261,-0.025 5426485\H,1.8521696042,-0.5928663176,-0.0118716713\C,-0.1459792591,-0. 0061921646,2.4143325532\H,0.5064483346,-0.7862081,2.8318947216\H,-1.16 30012312,-0.1755495508,2.7848476635\H,0.2122895053,0.9512262735,2.8186 009067\\Version=IBM-RS6000-G94RevD.2\HF=-233.393028\RMSD=7.404e-09\RMS F=4.350e-05\Dipole=0.054052,0.0131636,0.5140038\DipoleDeriv=0.,0.,0 Frequencies -- 130.2469 166.0793 254.8272 Frequencies -- 391.1240 399.1530 500.9251 Frequencies -- 603.3868 704.8596 764.0645 Frequencies -- 864.5343 879.4092 916.1426 Frequencies -- 960.1439 996.8479 1019.9356 Frequencies -- 1056.2904 1127.5570 1184.7043 Frequencies -- 1194.3135 1223.3947 1315.4774 Frequencies -- 1429.2648 1462.4291 1493.1771 Frequencies -- 1496.3283 1501.5540 1660.5599 Frequencies -- 1744.0389 3023.3046 3037.0992 Frequencies -- 3066.5933 3078.3181 3111.6976 Frequencies -- 3153.8985 3200.2572 3231.2992 9. 1,3-bismethylenecyclobutan-2-yl radical, 2-B1 (Cs near C2v) 1\1\GINC-FLO\Freq\UB3LYP\6-31+G(d)\C6H7(2)\BRIAN\28-Jan-1997\0\\#N BEC KE3LYP/6-31+G* GUESS=READ GEOM=CHECK FREQ=NORAMAN SCF=(DIRECT,TIGHT)\\ COMMENT: bismethylenecyclobutane radical b3lyp/6-31+g* frequency\\0,2\ C,1.0415329454,-0.0270227266,0.\C,-1.0398549051,-0.0645428713,0.\C,-0. 019596792,1.0902697512,0.\C,0.0184655237,-1.0239654588,0.\C,2.40125601 37,-0.0279183213,0.\C,-2.3987388212,-0.1144868888,0.\H,0.0378748417,-2 .1105620517,0.\H,-0.0311053303,1.7246176869,0.8945297926\H,-0.03110533 03,1.7246176869,-0.8945297926\H,2.9688967734,0.898406911,0.\H,2.964626 1025,-0.9577033788,0.\H,-2.9280728739,-1.0640711394,0.\H,-2.9994979699 ,0.7906933792,0.\\Version=IBM-RS6000-G94RevD.2\State=2-A"\HF=-232.7570 077\S2=0.791\S2-1=0.\S2A=0.751\RMSD=8.572e-09\RMSF=1.554e-05\Dipole=-0 .0007554,0.04007,0.\DipoleDeriv=0.,0 Frequencies -- 129.7160 270.7819 409.1043 Frequencies -- 435.9543 469.5007 593.2513 Frequencies -- 611.3994 637.3120 783.2449 Frequencies -- 796.3509 829.6008 838.7516 Frequencies -- 919.9000 934.4386 1010.3826 Frequencies -- 1029.5793 1115.3538 1172.4988 Frequencies -- 1219.8494 1271.9468 1324.0532 Frequencies -- 1406.6799 1454.2792 1493.6214 Frequencies -- 1538.3971 1641.2855 3054.1336 Frequencies -- 3100.3846 3159.2577 3160.2364 Frequencies -- 3206.6135 3243.9732 3244.1356 10. 1-methyl-3-methylenecyclobut-1-en-4-yl radical 2-A" (C1 near Cs) 1\1\GINC-FLO\Freq\UB3LYP\6-31+G(d)\C6H7(2)\BOB\19-Sep-1997\0\\#N B3LYP /6-31+G* GUESS=READ GEOM=CHECK FREQ=HPM SCF=DIRECT\\comment: B3LYP/6-3 1+G* 1-methyl-3-methylenecyclobut-1-en radical C1\\0,2\C,0.014879789,0 .0008224148,-2.4779907734\C,0.0088394893,0.0004586592,-1.1393157768\H, 0.94525934,0.0007242166,-3.0395449316\H,-0.9104123451,0.0012180917,-3. 0478648236\C,-1.0190014311,0.0004095995,-0.0589794574\C,1.0238425316,- 0.0001278987,-0.0495817065\C,-0.0081922156,-0.0001862354,0.925566637\H ,2.107730028,-0.0003724876,-0.0205970323\C,-0.0193771585,-0.0010524326 ,2.4181602058\H,-1.0419090886,0.0044339568,2.8090853209\H,0.4932351605 ,-0.8868282362,2.815452658\H,0.5034342357,0.8781195328,2.8167115743\H, -2.1032833585,0.0007602847,-0.0403975383\\Version=IBM-RS6000-G94RevD.2 \HF=-232.7411909\S2=0.779\S2-1=0.\S2A=0.75\RMSD=8.747e-10\RMSF=4.683e- 06\Dipole=0.0105554,-0.0005195,0.5341245\DipoleDeriv=0.,0., Frequencies -- 33.4740 145.8370 256.6712 Frequencies -- 407.7678 435.9802 510.3409 Frequencies -- 537.7437 618.7003 697.8520 Frequencies -- 721.5965 811.5326 868.3298 Frequencies -- 869.4212 936.2523 1053.3825 Frequencies -- 1053.6979 1146.2764 1173.2881 Frequencies -- 1182.7332 1269.2482 1426.9602 Frequencies -- 1467.2265 1502.1056 1505.7126 Frequencies -- 1552.0781 1741.8545 3038.0371 Frequencies -- 3087.0626 3121.8249 3161.8070 Frequencies -- 3233.1018 3237.7831 3241.0491