Chem Eur J 2002 SUPPORTING INFORMATION - Wiley- · PDF fileTable S1. Kinetic data for the ring flip process in 1d, derived from a line shape analysis. T [K] k [mol dm–3] 1/T [K–1

Copyright Wiley-VCH Verlag GmbH, 69451 Weinheim, 2002.

Chem. Eur. J. 2002

SUPPORTING INFORMATION

Persistent Bissilylated Arenium Ions

Rita Meyer, Karla Werner, Thomas Müller*

Table S1. Kinetic data for the ring flip process in 1d, derived from a line shape

analysis.

T [K] k [mol dm–3] 1/T [K–1] ln k

318 364.6 0.00314 5.8988

303.5 199 0.00329 5.2933

285 27.3 0.00351 3.30689

Figure S1. Arrhenius-type plot for the ring-flip process in 1d.

0.0031 0.0032 0.0033 0.0034 0.00353.0

3.5

4.0

4.5

5.0

5.5

6.0

6.5

ln[k

]

1/T [K−1]

lnk = (28.9 ±4.8) + (7265 ± 1456) /T

R = −0.980

Determination of the activation parameter for the ring-flip process in 1d.An Arrhenius-type evaluation of the kinetic data for the ring-flip process in 1d(see Table S4 and Figure S2) results in approximate values for the activation

energy EArr = (14.5 ± 2.9 kcal mol–1) and for the enthalpy of activation of ∆H‡ =

(15.1 ± 2.9 kcal mol–1) at T=300 K. The large errors are due to the limited

number of data points. A more precise kinetic study was not undertaken.

Table S2. Observed and calculated (GIAO/B3LYP/6-311G(d,p)//B3LYP/6-

31G(d) 13C NMR chemical shifts for a set of 8 model compounds

entry compound δ13Cexp δ13Ccalc notes1 C6H7

+ 52.2 53 benzenium ion, ref. a2 C6H7

+ 186.6 194.6 benzenium ion, ref. a3 C6H7

+ 136.9 142.4 benzenium ion, ref. a4 C6H7

+ 178.1 183.9 benzenium ion, ref. a5 C7H9

+ 49.5 49.1 toluenium ion, ref. b6 C7H9

+ 181.2 186.6 toluenium ion, ref. b7 C7H9

+ 139.4 143.3 toluenium ion, ref. b8 C7H9

+ 201.9 208.9 toluenium ion, ref. b9 C9H13

+ 51.9 52.6 mesitylenium ion, ref. c10 C9H13

+ 193.6 204.8 mesitylenium ion, ref. c11 C9H13

+ 133.8 139.2 mesitylenium ion, ref. c12 C9H13

+ 192.1 202.6 mesitylenium ion, ref. c13 C9H13

+ 28.4 31.7 mesitylenium ion, ref. c14 C9H13

+ 25.8 29.5 mesitylenium ion, ref. c15 C4H7

+ 201.5 213.8 methyl allyl cation, ref. d16 C4H7

+ 149.8 152.9 methyl allyl cation, ref. d17 C4H7

+ 255.1 259.2 methyl allyl cation, ref. d18 C4H7

+ 36.3 42.9 methyl allyl cation, ref. d19 C5H9

+ 175.0 190.2 1,1 dimethyl allyl cation, ref. e20 C5H9

+ 146.0 150.8 1,1 dimethyl allyl cation, ref. e21 C5H9

+ 274.3 274.6 1,1 dimethyl allyl cation, ref. e22 C5H9

+ 41.4 48.4 1,1 dimethyl allyl cation, ref. e23 C5H9

+ 33.1 32.6 1,1 dimethyl allyl cation, ref. e24 C6H11

+ 206.0 217.4 1,1,3 trimethyl allyl cation, ref. e25 C6H11

+ 143.9 147.1 1,1,3 trimethyl allyl cation, ref. e26 C6H11

+ 251.8 260.1 1,1,3 trimethyl allyl cation, ref. e27 C6H11

+ 37.2 44.3 1,1,3 trimethyl allyl cation, ref. e28 C6H11

+ 29.9 34 1,1,3 trimethyl allyl cation, ref. e29 C6H11

+ 27.4 29.6 1,1,3 trimethyl allyl cation, ref. e30 C7H13

+ 234.8 243.9 1,1,3,3 tetramethyl allyl cation, ref. f31 C7H13

+ 142.2 144.9 1,1,3,3 tetramethyl allyl cation, ref. f32 C5H9

+ 231.3 239.3 1,3 dimethyl allyl cation, ref. g33 C5H9

+ 147.0 149.9 1,3 dimethyl allyl cation, ref. g34 C5H9

+ 29.8 31.1 1,3 dimethyl allyl cation, ref. g[a] G. A. Olah, J. S. Staral, G. Asencio, G. Liang, D. A. Forsyth, G. D. Mateescu, J. Am. Chem.Soc. 1978, 100, 6299. [b] G. A. Olah, R. H. Schlosberg, R. D. Porter, Y. K. Mo, D. P. Kelly, G.D. Mateescu J. Am. Chem. Soc. 1972, 94, 2034.[c] C. A. Reed, N. L. P. Fackler, K.-C. Kim, D.Stasko, D. R. Evans, P. D. W. Boyd, C. E. F. Rickard, J. Am. Chem. Soc. 1999, 121, 6314.[d]H. Mayr, G. A. Olah, J. Am. Chem. Soc. 1977, 99, 510. [e] G. A. Olah, H. Mayr J. Am. Chem.Soc. 1976, 98, 7333. [f] G. A. Olah, P. R. Clifford, Y. Halpern, R. G. Johanson, J. Am. Chem.Soc. 1971, 93, 4219.[g] G. A. Olah, R. J. Spear J. Am. Chem. Soc. 1975, 97, 1539.

Figure S2. Plot of δ13C(calculated) vs. δ13C(experiment) and linear regression (data

from Table S2).

0 50 100 150 200 250 3000

50

100

150

200

250

300

δ δδδ13C(

calc

ulat

ed)

δδδδ13C(experiment)

δ13C(calculated) =(2.234±1.158) + (1.024±0.008) δ13C(experiment)

R = 0.999

Table S3. Cartesian coordinates of compounds 1a-g, 5a, 6a, 7-9, 11, TS(1a)optimized at the B3LYP/6-31G(d) level (in Å).

1a B3LYP/6-31G(d) Cs

Standard orientation: ---------------------------------------------------------- Center Atomic Coordinates (Angstroms) Number Number X Y Z ---------------------------------------------------------- 1 6 0.106419 -2.983294 0.000000 2 1 0.548358 -3.986707 0.000000 3 1 -0.980386 -3.136918 0.000000 4 6 0.534821 -2.246817 1.285125 5 6 0.534821 -2.246817 -1.285125 6 14 -0.263269 -0.569181 -1.615444 7 14 -0.263269 -0.569181 1.615444 8 1 0.289334 -2.863419 2.162641 9 1 0.289334 -2.863419 -2.162641 10 1 1.628805 -2.141104 1.305992 11 1 1.628805 -2.141104 -1.305992 12 6 0.534821 0.310791 3.073540 13 1 0.281847 -0.221800 3.998712 14 1 1.626601 0.339664 2.997714 15 1 0.172318 1.339159 3.180262 16 6 -2.123106 -0.686834 1.872067 17 1 -2.590505 0.292142 2.020821 18 1 -2.659639 -1.207286 1.074733 19 1 -2.285936 -1.259041 2.794975 20 6 0.534821 0.310791 -3.073540 21 1 0.281847 -0.221800 -3.998712 22 1 0.172318 1.339159 -3.180262 23 1 1.626601 0.339664 -2.997714 24 6 -2.123106 -0.686834 -1.872067 25 1 -2.590505 0.292142 -2.020821 26 1 -2.285936 -1.259041 -2.794975 27 1 -2.659639 -1.207286 -1.074733 28 6 0.126288 0.630072 0.000000 29 6 -0.745330 1.774458 0.000000 30 1 -1.820173 1.614366 0.000000 31 6 -0.261708 3.074187 0.000000 32 1 -0.946880 3.916243 0.000000 33 6 1.536386 0.924378 0.000000 34 1 2.245709 0.099227 0.000000 35 6 2.023278 2.221958 0.000000 36 1 3.092564 2.409106 0.000000 37 6 1.122368 3.295814 0.000000 38 1 1.502051 4.313995 0.000000 ----------------------------------------------------------

1b B3LYP/6-31G(d) C1

Standard orientation: --------------------------------------------------------------------- Center Atomic Atomic Coordinates (Angstroms) Number Number Type X Y Z --------------------------------------------------------------------- 1 6 0 -3.135043 0.018291 -0.934363 2 1 0 -3.974437 0.024264 -1.639983 3 1 0 -3.588108 0.020700 0.065518 4 6 0 -2.315697 -1.271365 -1.139904 5 6 0 -2.299105 1.297495 -1.138354 6 14 0 -0.911918 1.617906 0.100616 7 14 0 -0.933210 -1.611426 0.098925 8 1 0 -2.982371 -2.144680 -1.083181 9 1 0 -2.954193 2.179419 -1.079544 10 1 0 -1.904362 -1.290432 -2.159263 11 1 0 -1.888146 1.313019 -2.157908 12 6 0 0.120449 -3.078767 -0.427213 13 1 0 -0.474322 -3.997233 -0.348196 14 1 0 0.463890 -2.997276 -1.463620 15 1 0 0.999412 -3.204120 0.214848 16 6 0 -1.573570 -1.875185 1.848526 17 1 0 -0.765726 -2.044660 2.568252 18 1 0 -2.205365 -1.066943 2.225540 19 1 0 -2.187259 -2.785434 1.839238 20 6 0 0.160959 3.072023 -0.423694 21 1 0 -0.422698 3.997764 -0.346660 22 1 0 1.039575 3.187092 0.220791 23 1 0 0.506033 2.985738 -1.459173 24 6 0 -1.548602 1.887700 1.850662 25 1 0 -0.738563 2.042846 2.571164 26 1 0 -2.148111 2.807376 1.843135 27 1 0 -2.193120 1.088494 2.225462 28 6 0 0.325172 -0.005113 0.076523 29 6 0 1.178867 -0.011314 1.237261 30 1 0 0.721122 -0.011638 2.222866 31 6 0 2.558094 -0.020623 1.147437 32 1 0 3.161137 -0.029688 2.051151 33 6 0 1.024780 -0.008194 -1.185526 34 1 0 0.445793 -0.006165 -2.106830 35 6 0 2.403291 -0.016928 -1.273803 36 1 0 2.885714 -0.022950 -2.247246 37 6 0 3.199191 -0.021059 -0.109265 38 6 0 4.696349 -0.001297 -0.204999 39 1 0 5.163464 -0.489632 0.654865 40 1 0 5.049524 -0.479123 -1.123101 41 1 0 5.052095 1.038560 -0.221438 ---------------------------------------------------------------------

1c B3LYP/6-31G(d) C1

Standard orientation: --------------------------------------------------------------------- Center Atomic Atomic Coordinates (Angstroms) Number Number Type X Y Z --------------------------------------------------------------------- 1 6 0 3.077571 0.000318 -1.189682 2 1 0 3.870735 0.000372 -1.946973 3 1 0 3.592931 0.000472 -0.220339 4 6 0 2.241289 1.287450 -1.338903 5 6 0 2.241677 -1.287080 -1.338711 6 14 0 0.954067 -1.622266 0.004111 7 14 0 0.953799 1.622329 0.004104 8 1 0 2.909777 2.160938 -1.320101 9 1 0 2.910430 -2.160366 -1.319762 10 1 0 1.767586 1.311581 -2.330019 11 1 0 1.768039 -1.311506 -2.329855 12 6 0 -0.145339 3.088204 -0.429649 13 1 0 0.454383 4.006571 -0.410516 14 1 0 -0.585708 3.001879 -1.428108 15 1 0 -0.960621 3.218280 0.290969 16 6 0 1.793321 1.942721 1.659751 17 1 0 1.089581 2.221274 2.449480 18 1 0 2.415392 1.120349 2.023324 19 1 0 2.458202 2.803619 1.507126 20 6 0 -0.144871 -3.088161 -0.430059 21 1 0 0.454634 -4.006646 -0.410011 22 1 0 -0.960866 -3.217781 0.289834 23 1 0 -0.584297 -3.002122 -1.428959 24 6 0 1.793312 -1.942761 1.659863 25 1 0 1.089461 -2.221099 2.449566 26 1 0 2.457988 -2.803835 1.507327 27 1 0 2.415566 -1.120520 2.023418 28 6 0 -0.289312 -0.000044 0.035878 29 6 0 -1.233437 -0.000100 1.142655 30 6 0 -2.605802 -0.000274 0.892423 31 1 0 -3.290085 -0.000404 1.737706 32 6 0 -0.895778 -0.000142 -1.285354 33 6 0 -2.253074 -0.000328 -1.500091 34 1 0 -2.648322 -0.000513 -2.512134 35 6 0 -3.142189 -0.000347 -0.401524 36 6 0 -4.625444 0.000110 -0.629039 37 1 0 -4.923840 -0.875417 -1.218817 38 1 0 -5.185784 -0.006713 0.308506 39 1 0 -4.924642 0.884092 -1.205837 40 6 0 -0.799878 -0.000072 2.587549 41 1 0 -1.206519 0.878069 3.103969 42 1 0 -1.206083 -0.878476 3.103868 43 1 0 0.279687 0.000179 2.712975 44 1 0 -0.240027 -0.000128 -2.152296 ---------------------------------------------------------------------

1d B3LYP/6-31G(d) C1

Standard orientation: --------------------------------------------------------------------- Center Atomic Atomic Coordinates (Angstroms) Number Number Type X Y Z --------------------------------------------------------------------- 1 6 0 -2.667060 0.002576 -1.684050 2 1 0 -3.268365 0.003543 -2.601140 3 1 0 -3.389003 0.002660 -0.856905 4 6 0 -1.819787 -1.285794 -1.641518 5 6 0 -1.817879 1.289632 -1.640133 6 14 0 -0.855572 1.621444 -0.047564 7 14 0 -0.858101 -1.620418 -0.049110 8 1 0 -2.477480 -2.158777 -1.766619 9 1 0 -2.474267 2.163739 -1.764331 10 1 0 -1.140399 -1.313631 -2.504496 11 1 0 -1.138457 1.317385 -2.503090 12 6 0 0.309258 -3.086064 -0.231140 13 1 0 -0.279849 -4.006776 -0.324321 14 1 0 0.943541 -3.008147 -1.119850 15 1 0 0.960642 -3.204615 0.641979 16 6 0 -2.038922 -1.938839 1.383189 17 1 0 -1.524726 -2.220386 2.306575 18 1 0 -2.724955 -1.116635 1.604219 19 1 0 -2.655166 -2.798750 1.087463 20 6 0 0.313984 3.085452 -0.228555 21 1 0 -0.273740 4.007271 -0.319510 22 1 0 0.966595 3.201522 0.643977 23 1 0 0.947070 3.007968 -1.118154 24 6 0 -2.035455 1.940236 1.385414 25 1 0 -1.520448 2.222258 2.308219 26 1 0 -2.652134 2.799889 1.089855 27 1 0 -2.721096 1.117979 1.607424 28 6 0 0.357252 -0.000739 0.257321 29 6 0 1.020462 -0.001571 1.547198 30 6 0 2.418488 -0.001875 1.596377 31 1 0 2.914686 -0.002432 2.563485 32 6 0 1.229305 -0.000495 -0.903055 33 6 0 2.612286 -0.000885 -0.846511 34 6 0 3.191363 -0.001580 0.439859 35 6 0 0.284473 -0.002392 2.863103 36 1 0 0.568901 -0.882150 3.453619 37 1 0 0.572823 0.873746 3.457030 38 1 0 -0.797079 0.000144 2.755664 39 1 0 0.764211 0.000057 -1.885955 40 1 0 4.275443 -0.001900 0.531616 41 6 0 3.474591 -0.000515 -2.083838 42 1 0 4.125606 -0.881941 -2.110156 43 1 0 2.870157 -0.000814 -2.994934 44 1 0 4.124750 0.881551 -2.110192 ---------------------------------------------------------------------

1e B3LYP/6-31G(d) C1

Standard orientation: --------------------------------------------------------------------- Center Atomic Atomic Coordinates (Angstroms) Number Number Type X Y Z --------------------------------------------------------------------- 1 6 0 3.016074 0.316537 -0.500893 2 1 0 3.978877 0.435945 -1.012214 3 1 0 3.253850 0.288572 0.570659 4 6 0 2.132825 1.541332 -0.811003 5 6 0 2.376673 -1.018665 -0.933567 6 14 0 0.868152 -1.560269 0.073017 7 14 0 0.485838 1.688275 0.115188 8 1 0 2.672320 2.456367 -0.522451 9 1 0 3.103785 -1.831103 -0.785714 10 1 0 1.989394 1.628997 -1.894504 11 1 0 2.172958 -1.004396 -2.009797 12 6 0 -0.651324 2.974692 -0.657903 13 1 0 -0.188064 3.963258 -0.549333 14 1 0 -0.831178 2.811637 -1.724777 15 1 0 -1.622132 3.012820 -0.151154 16 6 0 0.874436 2.210167 1.883281 17 1 0 -0.008051 2.379620 2.505348 18 1 0 1.554792 1.539211 2.415799 19 1 0 1.390023 3.175853 1.791255 20 6 0 0.016842 -3.099141 -0.606853 21 1 0 0.711429 -3.946123 -0.547274 22 1 0 -0.863345 -3.357603 -0.006889 23 1 0 -0.302623 -3.011138 -1.649240 24 6 0 1.486011 -1.955764 1.811028 25 1 0 0.718812 -2.363159 2.473763 26 1 0 2.241000 -2.742322 1.675876 27 1 0 1.984053 -1.125968 2.321918 28 6 0 -0.573888 -0.097841 0.015556 29 6 0 -1.491731 -0.176685 1.156283 30 6 0 -2.871220 -0.238771 0.962272 31 6 0 -1.209769 -0.121070 -1.315310 32 6 0 -2.591130 -0.185528 -1.439950 33 6 0 -3.417791 -0.243616 -0.316149 34 1 0 -4.496026 -0.292621 -0.442972 35 1 0 -3.526617 -0.288013 1.827407 36 1 0 -3.037650 -0.191967 -2.429452 37 6 0 -1.047732 -0.208198 2.599166 38 1 0 -1.328496 -1.169318 3.047466 39 1 0 0.017818 -0.068934 2.741560 40 1 0 -1.576263 0.563491 3.170127 41 6 0 -0.428096 -0.091975 -2.608654 42 1 0 0.044496 -1.060382 -2.808709 43 1 0 -1.095931 0.117282 -3.447580 44 1 0 0.365812 0.655065 -2.617813 ---------------------------------------------------------------------

1f B3LYP/6-31G(d) C1

Standard orientation: --------------------------------------------------------------------- Center Atomic Atomic Coordinates (Angstroms) Number Number Type X Y Z --------------------------------------------------------------------- 1 6 0 -3.249863 0.003332 -0.858746 2 1 0 -4.103547 0.004539 -1.547015 3 1 0 -3.682127 0.003635 0.150306 4 6 0 -2.429203 -1.283500 -1.079788 5 6 0 -2.426143 1.288290 -1.079210 6 14 0 -1.013893 1.612414 0.131120 7 14 0 -1.018132 -1.611161 0.130967 8 1 0 -3.090460 -2.159481 -1.004328 9 1 0 -3.085263 2.165842 -1.003218 10 1 0 -2.040846 -1.304020 -2.107977 11 1 0 -2.037834 1.308402 -2.107427 12 6 0 0.034389 -3.076072 -0.405238 13 1 0 -0.547691 -3.999643 -0.297111 14 1 0 0.347505 -3.003854 -1.451817 15 1 0 0.932409 -3.182678 0.213304 16 6 0 -1.628970 -1.872988 1.892116 17 1 0 -0.808546 -2.016627 2.603033 18 1 0 -2.275560 -1.076949 2.270335 19 1 0 -2.220842 -2.797686 1.897779 20 6 0 0.042241 3.074429 -0.405848 21 1 0 -0.536587 3.999766 -0.295361 22 1 0 0.942019 3.177466 0.210736 23 1 0 0.352682 3.002344 -1.453228 24 6 0 -1.622594 1.875882 1.892724 25 1 0 -0.801009 2.022326 2.601737 26 1 0 -2.216284 2.799417 1.897932 27 1 0 -2.266769 1.079159 2.273570 28 6 0 0.233735 -0.001350 0.071729 29 6 0 1.106273 -0.001572 1.212814 30 1 0 0.664092 -0.001558 2.205895 31 6 0 2.493905 -0.001723 1.103288 32 6 0 0.880555 -0.001494 -1.212984 33 1 0 0.262979 -0.001469 -2.109222 34 6 0 2.263417 -0.001666 -1.363662 35 6 0 3.042163 -0.001761 -0.192259 36 1 0 4.126569 -0.001897 -0.293686 37 6 0 3.392986 -0.001957 2.315488 38 1 0 4.044165 0.879527 2.322413 39 1 0 2.815394 -0.001370 3.243663 40 1 0 4.043042 -0.884272 2.322862 41 6 0 2.921900 -0.001731 -2.721609 42 1 0 3.560527 -0.883242 -2.848909 43 1 0 2.182341 -0.002555 -3.526777 44 1 0 3.559252 0.880618 -2.849592 ---------------------------------------------------------------------

1g B3LYP/6-31G(d) C1

Standard orientation: --------------------------------------------------------------------- Center Atomic Atomic Coordinates (Angstroms) Number Number Type X Y Z --------------------------------------------------------------------- 1 6 0 3.276802 0.071239 -0.640900 2 1 0 4.217922 0.106497 -1.202879 3 1 0 3.567405 0.022354 0.416914 4 6 0 2.487501 1.368400 -0.908008 5 6 0 2.501790 -1.203605 -1.032904 6 14 0 1.005638 -1.613154 0.051018 7 14 0 0.899319 1.651547 0.088518 8 1 0 3.116263 2.232391 -0.644368 9 1 0 3.162739 -2.075988 -0.919582 10 1 0 2.302946 1.473173 -1.984124 11 1 0 2.244056 -1.172732 -2.097369 12 6 0 -0.160658 3.021545 -0.653252 13 1 0 0.380006 3.972449 -0.570457 14 1 0 -0.392148 2.866734 -1.711500 15 1 0 -1.106658 3.136298 -0.112099 16 6 0 1.406988 2.165597 1.829748 17 1 0 0.566424 2.401378 2.487319 18 1 0 2.061124 1.452453 2.340324 19 1 0 1.984096 3.091772 1.704146 20 6 0 0.005784 -3.081587 -0.581243 21 1 0 0.632843 -3.980716 -0.540277 22 1 0 -0.868638 -3.266090 0.053381 23 1 0 -0.343848 -2.974036 -1.612098 24 6 0 1.673872 -2.059152 1.758304 25 1 0 0.908510 -2.399507 2.460113 26 1 0 2.353327 -2.906165 1.591810 27 1 0 2.263212 -1.272979 2.239931 28 6 0 -0.298266 -0.031974 0.063941 29 6 0 -1.168307 -0.054373 1.246965 30 6 0 -2.551752 -0.045171 1.121001 31 1 0 -3.159321 -0.052646 2.022938 32 6 0 -1.011011 -0.021276 -1.228984 33 6 0 -2.394730 -0.011680 -1.279744 34 1 0 -2.886231 0.010036 -2.248684 35 6 0 -3.191521 -0.026705 -0.123588 36 6 0 -4.689116 -0.046332 -0.221429 37 1 0 -5.039970 0.400157 -1.155903 38 1 0 -5.049200 -1.084267 -0.199050 39 1 0 -5.154417 0.475179 0.620061 40 6 0 -0.655701 -0.094461 2.667770 41 1 0 -1.089743 0.729628 3.245135 42 1 0 -0.987557 -1.020202 3.153164 43 1 0 0.423702 -0.037908 2.753353 44 6 0 -0.300124 -0.035252 -2.563315 45 1 0 0.032798 -1.047940 -2.820489 46 1 0 -0.979242 0.287070 -3.356446 47 1 0 0.580895 0.604832 -2.592952 ---------------------------------------------------------------------

1a(H) B3LYP/6-31G(d) C1

Standard orientation: --------------------------------------------------------------------- Center Atomic Atomic Coordinates (Angstroms) Number Number Type X Y Z --------------------------------------------------------------------- 1 6 0 2.415592 1.526020 -0.812648 2 1 0 3.138380 2.037593 -1.464749 3 1 0 2.747061 1.736175 0.214382 4 6 0 1.011448 2.126064 -1.037988 5 6 0 2.478487 0.006378 -1.076767 6 14 0 1.420187 -1.066241 0.086770 7 14 0 -0.375393 1.514162 0.120946 8 1 0 1.060209 3.220739 -0.941373 9 1 0 3.519406 -0.340725 -1.001751 10 1 0 0.703926 1.939087 -2.078052 11 1 0 2.178965 -0.190097 -2.117477 12 6 0 -2.001678 2.298734 -0.454550 13 1 0 -1.903926 3.391615 -0.480620 14 1 0 -2.279734 1.960436 -1.457751 15 1 0 -2.828293 2.049599 0.218640 16 6 0 -0.044137 2.136473 1.886627 17 1 0 -0.838653 1.827530 2.576160 18 1 0 0.907553 1.791327 2.303582 19 1 0 -0.024086 3.233784 1.887584 20 6 0 1.476193 -2.869129 -0.501299 21 1 0 2.507320 -3.244113 -0.497754 22 1 0 0.885870 -3.525240 0.149402 23 1 0 1.081568 -2.976080 -1.517774 24 6 0 2.148361 -1.013627 1.838736 25 1 0 1.531052 -1.575040 2.549552 26 1 0 3.143793 -1.475616 1.837466 27 1 0 2.261639 0.002976 2.229206 28 6 0 -0.398949 -0.428177 0.052723 29 6 0 -1.212720 -1.089307 1.209530 30 1 0 -0.974822 -0.609787 2.165706 31 6 0 -2.706810 -1.071067 0.966403 32 1 0 -3.374903 -1.058009 1.825462 33 6 0 -0.995068 -0.799780 -1.285891 34 1 0 -0.368411 -0.713275 -2.173568 35 6 0 -2.286785 -1.160701 -1.432265 36 1 0 -2.685294 -1.392751 -2.417079 37 6 0 -3.190963 -1.161844 -0.283633 38 1 0 -4.262649 -1.214647 -0.463503 39 1 0 -0.910918 -2.146593 1.332418 ---------------------------------------------------------------------

5a B3LYP/6-31G(d) C1Standard orientation:

--------------------------------------------------------------------- Center Atomic Atomic Coordinates (Angstroms) Number Number Type X Y Z --------------------------------------------------------------------- 1 14 0 1.051880 0.843906 0.103806 2 6 0 -0.292010 -0.536745 0.041459 3 6 0 -1.737364 -0.014721 0.023671 4 1 0 -0.117557 -1.155302 -0.849126 5 1 0 -0.159253 -1.196621 0.909468 6 6 0 -2.765296 -1.216840 -0.027475 7 1 0 -1.925651 0.592999 0.917942 8 1 0 -1.885321 0.636240 -0.847639 9 1 0 -2.576360 -1.819534 -0.922636 10 1 0 -2.621475 -1.852412 0.853391 11 6 0 0.787337 2.011305 -1.361977 12 1 0 1.585376 2.761007 -1.412502 13 1 0 0.792355 1.471209 -2.315999 14 1 0 -0.158501 2.562190 -1.285322 15 6 0 0.862185 1.795813 1.728797 16 1 0 0.958438 1.131535 2.595637 17 1 0 1.646072 2.556924 1.818233 18 1 0 -0.101339 2.316047 1.803061 19 14 0 -4.457877 -0.491894 -0.058435 20 6 0 -5.300153 0.034302 1.502057 21 1 0 -6.339495 -0.321165 1.510778 22 1 0 -4.791057 -0.328972 2.398976 23 1 0 -5.351217 1.132189 1.545742 24 6 0 -5.275767 -0.101270 -1.671376 25 1 0 -4.537530 0.141900 -2.444286 26 1 0 -5.815216 -0.995064 -2.022363 27 1 0 -6.003352 0.711887 -1.587443 28 6 0 2.735776 0.008024 -0.002367 29 6 0 3.881749 0.777325 -0.284447 30 6 0 5.148873 0.197406 -0.342707 31 6 0 5.299944 -1.173111 -0.122604 32 6 0 4.180030 -1.957090 0.156451 33 6 0 2.914741 -1.370432 0.215388 34 1 0 3.791127 1.847103 -0.462886 35 1 0 6.016950 0.813212 -0.561398 36 1 0 6.285815 -1.627232 -0.169177 37 1 0 4.291250 -3.024455 0.327591 38 1 0 2.059623 -2.005641 0.435538 ---------------------------------------------------------------------

7 B3LYP/6-31G(d) C2v

Standard orientation: --------------------------------------------------------------------- Center Atomic Atomic Coordinates (Angstroms) Number Number Type X Y Z --------------------------------------------------------------------- 1 6 0 0.000000 0.000000 -1.400319 2 6 0 0.000000 1.255854 -0.629621 3 6 0 0.000000 -1.255854 -0.629621 4 6 0 0.000000 1.242255 0.742140 5 6 0 0.000000 -1.242255 0.742140 6 1 0 0.000000 2.193488 -1.179388 7 1 0 0.000000 -2.193488 -1.179388 8 6 0 0.000000 0.000000 1.416275 9 1 0 0.000000 0.000000 2.504100 10 1 0 0.853310 0.000000 -2.108757 11 1 0 -0.853310 0.000000 -2.108757 12 1 0 0.000000 2.164804 1.313112 13 1 0 0.000000 -2.164804 1.313112 ---------------------------------------------------------------------

8 B3LYP/6-31G(d) C1

Standard orientation: --------------------------------------------------------------------- Center Atomic Atomic Coordinates (Angstroms) Number Number Type X Y Z --------------------------------------------------------------------- 1 6 0 -1.903450 -0.000051 0.007269 2 6 0 -1.121183 1.250854 0.001388 3 6 0 -1.121115 -1.250897 0.001391 4 6 0 0.243879 1.236152 -0.009671 5 6 0 0.243935 -1.236061 -0.009679 6 1 0 -1.663819 2.192673 0.004009 7 1 0 -1.663707 -2.192748 0.004015 8 6 0 0.953573 0.000087 -0.015100 9 1 0 -2.614165 -0.000084 -0.842238 10 1 0 -2.597061 -0.000083 0.871031 11 1 0 0.806763 2.164438 -0.017603 12 1 0 0.806893 -2.164305 -0.017614 13 6 0 2.442339 0.000044 0.002998 14 1 0 2.860122 -0.895036 -0.465906 15 1 0 2.860439 0.897383 -0.461198 16 1 0 2.776674 -0.003010 1.053923 ---------------------------------------------------------------------

9 B3LYP/6-31G(d) C1

Standard orientation: --------------------------------------------------------------------- Center Atomic Atomic Coordinates (Angstroms) Number Number Type X Y Z --------------------------------------------------------------------- 1 6 0 0.000724 -1.418004 0.014048 2 6 0 -1.277863 -0.649412 0.000400 3 6 0 1.278540 -0.648136 0.000429 4 6 0 -1.234958 0.720737 -0.011035 5 6 0 1.234265 0.721978 -0.011069 6 6 0 -0.000691 1.421799 -0.014829 7 1 0 0.001146 -2.134710 -0.825249 8 1 0 0.001018 -2.084694 0.894623 9 1 0 -2.158235 1.292598 -0.020690 10 1 0 2.156966 1.294761 -0.020752 11 6 0 -0.001510 2.914165 0.005448 12 1 0 0.893801 3.331464 -0.463230 13 1 0 -0.895975 3.330380 -0.465864 14 1 0 -0.003372 3.251095 1.054318 15 6 0 -2.563896 -1.410938 -0.001990 16 1 0 -3.429562 -0.745771 0.022233 17 1 0 -2.636393 -2.042581 -0.897458 18 1 0 -2.618416 -2.087931 0.860367 19 6 0 2.565337 -1.408364 -0.001942 20 1 0 3.430338 -0.742328 0.022186 21 1 0 2.620572 -2.085417 0.860293 22 1 0 2.638429 -2.039813 -0.897529 ---------------------------------------------------------------------

6a B3LYP/6-31G(d) C1

Standard orientation: --------------------------------------------------------------------- Center Atomic Atomic Coordinates (Angstroms) Number Number Type X Y Z --------------------------------------------------------------------- 1 14 0 2.877819 -0.879851 0.245690 2 6 0 1.303309 0.174990 -0.048910 3 6 0 -0.019411 -0.607400 0.027730 4 1 0 1.284329 0.994130 0.684050 5 1 0 1.383199 0.651350 -1.036670 6 6 0 -1.254421 0.293680 -0.257420 7 1 0 0.001449 -1.433580 -0.694480 8 1 0 -0.119081 -1.064870 1.021530 9 1 0 -1.271771 1.126380 0.457950 10 1 0 -1.150941 0.739280 -1.256110 11 6 0 2.833809 -1.581811 2.004270 12 1 0 3.750489 -2.142401 2.221550 13 1 0 2.757729 -0.783411 2.751780 14 1 0 1.991849 -2.269241 2.154660 15 6 0 2.906349 -2.302561 -1.004710 16 1 0 2.859579 -1.931951 -2.035530 17 1 0 3.829979 -2.885661 -0.912390 18 1 0 2.071459 -2.998501 -0.855120 19 14 0 -2.865511 -0.666960 -0.137390 20 6 0 -2.982381 -2.116470 -1.320280 21 1 0 -3.926871 -2.661520 -1.230740 22 1 0 -2.842431 -1.821750 -2.365880 23 1 0 -2.175671 -2.819300 -1.073850 24 6 0 -3.441321 -1.048930 1.599140 25 1 0 -3.420511 -0.172010 2.252350 26 1 0 -4.442631 -1.487790 1.627250 27 1 0 -2.748901 -1.789670 2.021640 28 6 0 -4.320301 0.781940 -1.060250 29 1 0 -3.732631 0.795310 -1.979820 30 6 0 -4.196350 1.881720 -0.161550 31 6 0 -5.167090 2.105581 0.805430 32 1 0 -3.333720 2.536790 -0.236230 33 1 0 -5.065360 2.931931 1.501630 34 6 0 -5.509231 -0.002599 -1.028060 35 6 0 -6.473601 0.229931 -0.055730 36 1 0 -5.651981 -0.785809 -1.766230 37 1 0 -7.371551 -0.378559 -0.019330 38 6 0 -6.299520 1.279991 0.856050 39 1 0 -7.063220 1.467831 1.605590 40 6 0 4.391769 0.220779 0.014430 41 6 0 5.682269 -0.337901 0.100410 42 6 0 6.825939 0.443639 -0.060940 43 6 0 6.705940 1.811759 -0.314290 44 6 0 5.439440 2.389589 -0.404160 45 6 0 4.298750 1.600719 -0.241220 46 1 0 5.803599 -1.402081 0.295900 47 1 0 7.809469 -0.013052 0.009980 48 1 0 7.595280 2.423009 -0.441080 49 1 0 5.339220 3.453759 -0.601350 50 1 0 3.323640 2.076859 -0.316820 ---------------------------------------------------------------------

11 B3LYP/6-31G(d) C1

Standard orientation: --------------------------------------------------------------------- Center Atomic Atomic Coordinates (Angstroms) Number Number Type X Y Z --------------------------------------------------------------------- 1 6 0 -0.000756 -2.408885 -0.962955 2 1 0 -0.443568 -3.114109 -1.676631 3 1 0 -0.301356 -2.764952 0.031003 4 6 0 1.534744 -2.455866 -1.098759 5 6 0 -0.585446 -1.005745 -1.218179 6 14 0 -0.142006 0.348576 0.015019 7 14 0 2.532269 -1.461074 0.157546 8 1 0 1.882416 -3.494556 -0.997099 9 1 0 -1.684815 -1.049424 -1.198705 10 1 0 1.825409 -2.154680 -2.115410 11 1 0 -0.324292 -0.672459 -2.232849 12 6 0 4.359969 -1.418013 -0.290709 13 1 0 4.782752 -2.424954 -0.187123 14 1 0 4.529784 -1.093900 -1.322715 15 1 0 4.927835 -0.755583 0.372054 16 6 0 2.323655 -2.102711 1.915714 17 1 0 2.790928 -1.454470 2.664587 18 1 0 1.286166 -2.278091 2.212543 19 1 0 2.840306 -3.069943 1.968862 20 6 0 -0.731682 2.039432 -0.551070 21 1 0 -1.826891 2.056771 -0.486789 22 1 0 -0.349274 2.845107 0.085012 23 1 0 -0.453772 2.257650 -1.586973 24 6 0 -0.738942 0.001728 1.761524 25 1 0 -0.475002 0.807584 2.454618 26 1 0 -1.835459 -0.043134 1.718592 27 1 0 -0.388698 -0.943330 2.183331 28 6 0 -4.682141 -0.898049 1.016158 29 6 0 -4.646703 -1.246252 -0.337932 30 6 0 -4.661858 -0.248677 -1.316847 31 6 0 -4.712475 1.098014 -0.942434 32 6 0 -4.747253 1.445968 0.410755 33 6 0 -4.732440 0.447661 1.390338 34 1 0 -4.691627 -1.674473 1.776612 35 1 0 -4.630354 -2.293317 -0.629073 36 1 0 -4.656830 -0.519723 -2.369378 37 1 0 -4.746731 1.872566 -1.704131 38 1 0 -4.808302 2.491302 0.702039 39 1 0 -4.782002 0.718115 2.441865 40 6 0 1.933186 0.473753 0.045566 41 6 0 2.325068 1.242762 1.194827 42 6 0 2.313948 1.023587 -1.228578 43 1 0 2.069095 0.873160 2.184017 44 6 0 3.012266 2.442655 1.084061 45 6 0 3.002433 2.221179 -1.343692 46 1 0 2.048745 0.482464 -2.134277 47 1 0 3.290229 3.001446 1.972306 48 6 0 3.350775 2.929495 -0.185738 49 1 0 3.891171 3.868135 -0.273685 50 1 0 3.272360 2.609552 -2.320806 ---------------------------------------------------------------------

TS(1a) B3LYP/6-31G(d) C1

Standard orientation: --------------------------------------------------------------------- Center Atomic Atomic Coordinates (Angstroms) Number Number Type X Y Z --------------------------------------------------------------------- 1 6 0 -2.917974 0.000036 -0.595745 2 1 0 -4.012501 0.000055 -0.656998 3 1 0 -2.562488 -0.000083 -1.636002 4 6 0 -2.452397 1.267940 0.139803 5 6 0 -2.452448 -1.267734 0.140077 6 14 0 -0.612045 -1.685929 0.101070 7 14 0 -0.611958 1.685953 0.101047 8 1 0 -2.941531 2.153439 -0.292610 9 1 0 -2.941731 -2.153300 -0.292033 10 1 0 -2.789980 1.222287 1.184089 11 1 0 -2.789872 -1.221775 1.184403 12 6 0 -0.114374 2.621809 1.655730 13 1 0 -0.708112 3.544184 1.698738 14 1 0 -0.322284 2.065299 2.576004 15 1 0 0.941673 2.910651 1.655946 16 6 0 -0.201981 2.686311 -1.441170 17 1 0 0.866581 2.907105 -1.530148 18 1 0 -0.531777 2.201297 -2.366498 19 1 0 -0.732406 3.644903 -1.374436 20 6 0 -0.114337 -2.621981 1.655590 21 1 0 -0.708174 -3.544293 1.698587 22 1 0 0.941676 -2.910944 1.655638 23 1 0 -0.322064 -2.065540 2.575946 24 6 0 -0.202379 -2.686146 -1.441321 25 1 0 0.866092 -2.907406 -1.530233 26 1 0 -0.733249 -3.644510 -1.374857 27 1 0 -0.531846 -2.200783 -2.366583 28 6 0 0.602743 -0.000017 0.009509 29 6 0 1.288132 -0.000053 -1.260624 30 6 0 1.471045 -0.000021 1.161379 31 6 0 2.668986 -0.000093 -1.368656 32 6 0 2.852897 -0.000059 1.061188 33 1 0 1.025618 0.000017 2.151713 34 6 0 3.451500 -0.000096 -0.205763 35 1 0 3.143553 -0.000115 -2.344895 36 1 0 4.535157 -0.000123 -0.287761 37 1 0 3.468298 -0.000054 1.955343 38 1 0 0.698927 -0.000041 -2.172983 ---------------------------------------------------------------------

Table S4 . Absolute energies of arenium ions and related compounds.cpd. PG B3LYP/ B3LYP/

6–31G(d)b 6–311G(d,p)b

1a Cs –1088.06091 –1088.24345

[0] 205.5

1a(TS)[a] C1 –1088.05004 –1088.23225

[-1] 205.9

1b C1 –1127.38561 –1127.57804

[0] 222.7

1c C1 –1166.69991 –1166.90225

[0] 240.4

1d C1 –1166.69643 –1166.89847

[0] 240.4

1e C1 –1166.68409 –1166.88616

[0] 241.4

1f C1 –1166.70290 –1166.90474

[0] 240.0

1g C1 –1206.00828 –1206.22017

[0] 258.8

1a(H) C1 –1088.85979 –1089.05215

[0] 211.5

5a C1 –1088.01914 –1088.20506

[0] 203.5

[5a/C6H6], 6a C1 –1320.30453 –1320.54558

[0] 268.9

Table S4. continued.

[1a/C6H6], 11 C1 –1320.31613 –1320.55686

[0] 269.2

C6H6 D6h –232.24865 –232.30848

[0] 63.2

C6H7+, 7 C2v –232.55629 –232.61024

[0] 69.6

C6H8, 7(H) C2 –233.41894 –233.48128

[0] 77.1

C7H9+, 8 Cs –271.88743 –271.95153

[0], 87.0

C9H13+, 9 Cs –350.54274 –350.62495

[0] 121.8

Ph3C+ D3 -732.82511 –732.99007

[0] 176.5

Ph3CH C3 -733.66090 –733.83723

[0] 182.9

[a] Transition state for the isomerization of the chair conformation of the 1,3 disilahexane ring in 1a into the twisted boat conformation.

Figure S3. 79.5 MHz 29Si {1H} Inept NMR spectrum (upper trace) and 100 MHz 13C {1H} NMR spectrum of 1a in [D6] benzene (lower

trace, ! triphenylmethane).

100 50 0 -50 -100 PPM

150 100 50 0 PPM

[B(C6F5)4]−

Me2Si SiMe2

+

Figure S4. 79.5 MHz 29Si {1H} Inept NMR spectrum (upper trace) and 100 MHz 13C {1H} NMR spectrum of 1b in [D6] benzene (lower

trace, ! triphenylmethane, " Ph3C+).

150 100 50 0 PPM

100 50 0 -50 -100 PPM

[B(C6F5)4]−

Me2Si SiMe2

+

Figure S5. 49.7 MHz 29Si {1H} Inept NMR spectrum (upper trace) and 62.9 MHz 13C {1H} NMR spectrum of 1d in [D6] benzene (lower

trace, ! triphenylmethane).

150 100 50 0 PPM

150 100 50 0 -50 -100 PPM

Me2Si SiMe2

[B(C6F5)4]−+

Figure S6. 49.7 MHz 29Si {1H} Inept NMR spectrum (upper trace) and 62.9 MHz 13C {1H} NMR spectrum of 1e in [D6] benzene (lower

trace, ! triphenylmethane).

150 100 50 0 PPM

150 100 50 0 -50 -100 PPM

[B(C6F5)4]

Me2Si SiMe2

+

Figure S7. 49.7 MHz 29Si {1H} Inept NMR spectrum (upper trace) and 62.9 MHz 13C {1H} NMR spectrum of 1f in [D6] benzene (lower

trace, ! triphenylmethane, " [B(C6F5)4]– ).

150 100 50 0 PPM

150 100 50 0 -50 -100 PPM

[B(C6F5)4]

Me2Si SiMe2

+

Figure S8. 79.5 MHz 29Si {1H} Inept NMR spectrum (upper trace) and 100 MHz 13C {1H} NMR spectrum of 1g in [D6] benzene (lower

trace, ! triphenylmethane, " Ph3C+ ).

150 100 50 0 PPM

100 50 0 -50 -100 PPM

[B(C6F5)4]−

Me2Si SiMe2

+

Figure S9. Calculated charge distribution in arenium ions and related compounds (NBO[a] HF/6-311G(d)//B3LYP/6-31G(d)).

H H−0.52

0.35

−0.09

0.40

7

Me2Si SiMe2Me2Si SiMe2

1a

0.29

−0.880.21

−0.03

0.24

1.05b

0.22

−0.03

0.05−0.44 1.35b 0.93b−0.45 −0.41

−0.02 −0.530.01

0.00

0.04

0.02

0.01

+

5a

Me2Si SiMe2−0.95

0.04

−0.05

0.02

0.93b

0.01

−0.03

0.01−0.45

HH

−0.45

0.95b

1a(H)

Σ(dienyl): 0.92c Σ(dienyl): 0.61c Σ(dienyl): −0.01c

[a] NBO 4.0. E. D. Glendening; J. K. Badenhoop, A. E. Reed, J. E. Carpenter, F. Weinhold Theoretical Chemistry Institute, University

of Wisconsin, Madison, WI, 1996. [b] calculated group charge of the SiMe2 group. [c] calculated charge of the dienyl group (CH)5+(1a,

7) or (CH)4CH2 (1a(H)).