Subject: Re: CCL:How can one get the chiral form of [5]Helicene, when using Spartan?

From: [email-masked] (Alan Shusterman)
Date: 30 Aug 96 09:17:36 PDT

--- You wrote:
Question: How can one get the chiral form of the [5] Helicene, When using 
Spartan?
--- end of quoted material ---
A small trick is involved.  Select the Naphthyl fragment from Rings in the
builder.  Put the fragment in the builder window, and then click on the
1-position to make 1,1'-binaphthyl (note: make sure the little circle on the
Naphthyl fragment is also on the 1-position).  Then press space bar and the
middle mouse button to do an internal rotation (this makes the binaphthyl
nonplanar).  Finally, add two aromatic C fragments to make the "middle" benzene
ring.  Minimize and you should get C2-symmetry (chiral) [5]helicene.

You may be interested in the following paper: RH Janke, et al, "Racemization
Barriers of Helicenes: A Computational Study" JACS, 118(25), 6031 (1996).

Alan Shusterman
Department of Chemistry
Reed College
Portland, OR  97202

---

From: "Wayne Huang" <[email-masked]>
Date: Fri, 30 Aug 1996 10:05:52 -0700

On Aug 29,  5:37pm, Omer Katzenelson wrote:
> Subject: CCL:How can one get the chiral form of [5]Helicene, when using Sp
> Dear CCLers,
>
> [5] Helicene has a helical structure made up of 5 ortho-condensed
> aromatic rings, and  was found to be chiral. Depending on the temperature
> racemization occurs.
> I was calculating the structure of [5] Helicene in Spartan using various
> models: AM1, Sybyl, etc. All of these structure had a C2v point group
> symmetry, which means that the structure is a-chiral.

Omer,

I have 9-helicene structures with both chiral forms (left- and right-handed),
which have been optimized by AM1. The chiral structure was generated from
its counter-part by symmetry operation with XZ plane reflection. Both
have C2 symmetry. I have merged these two together. You should be able to
build any chiral helicene by manipulating this template. The input file
is attached. Use Import feature to open it with Spartan.

Have fun!

--Wayne

-- 
+---------------------------------------------------------------------+
|  Wayne Huang, Ph.D.    	|  18401 Von Karman, Suite 370        | 
|  Computational Chemist 	|  Irvine, California 92715           |
|  Wavefunction, Inc.    	|  (714)955-2120 Fax: (714)955-2118   |  
|  [email-masked]     	|  World Wide Web: http://wavefun.com |
+---------------------------------------------------------------------+
 AM1 OPT 
Chiral 9-helicene structure
0 1
 1   1.074571013  12.378871918   0.354416996
 6   1.344658732  11.313071251   0.312904656
 1   3.415607929  11.607824326   0.818288088
 6   2.625231743  10.897450447   0.533199549
 6   0.612907767   8.977306366   0.064763427
 6   2.975026369   9.527014732   0.352405518
 6   0.313987732  10.359113693   0.066291735
 6   1.998730063   8.596376419  -0.071275987
 6   4.310030937   9.094069481   0.608663440
 6  -1.018278360  10.801406860  -0.188247338
 6   0.868165433   7.070253849  -2.573396206
 6  -0.491448194   8.057345390   0.197852433
 6   4.647901535   7.783419609   0.442380637
 1   5.039278984   9.830986977   0.976633251
 1   5.640694141   7.407610893   0.731839478
 6   3.727969885   6.876674652  -0.163909525
 6   4.089210510   5.510530949  -0.342011392
 6   2.465238810   7.338837147  -0.604761124
 6   3.248797655   4.658549786  -0.999333620
 1   5.041856289   5.159195900   0.081462994
 1   3.470214605   3.583462238  -1.073565245
 6   2.094184875   5.166082382  -1.661836028
 6   1.292562366   4.282688141  -2.452418327
 6   1.774032354   6.537084579  -1.581722140
 6  -2.595361471   6.230172157  -0.236401945
 6  -0.419714093   6.744327068   0.785951614
 6  -1.760046005   8.499480247  -0.246681929
 6  -2.797903776   7.555770397  -0.493313402
 6  -1.415895939   5.807482719   0.441701323
 6   0.530875623   6.363833427   1.805699468
 6  -2.006173372   9.892987251  -0.430004388
 1  -3.747625351   7.917087555  -0.914952219
 6  -1.275457144   4.433709621   0.817238271
 1  -3.352534533   5.476280689  -0.498480886
 1  -1.214743614  11.883316994  -0.221773043
 1  -3.015588522  10.212047577  -0.729898095
 6   2.323687315   5.559823513   3.839003086
 6   0.633819699   5.002697945   2.189162493
 6   1.288176894   7.314165115   2.534725904
 6   2.162646055   6.923360348   3.526830196
 6   1.564687729   4.615666866   3.183032751
 6  -0.255827725   4.034807682   1.623620868
 1   1.159378648   8.386232376   2.317704678
 1   2.737838268   7.676791668   4.084859371
 1   1.656844258   3.548492908   3.434548855
 1   3.042804003   5.261397839   4.615293503
 6  -0.874919116   8.044023514  -4.575484753
 6   0.794357717   8.453250885  -2.873372555
 6   0.105665915   6.179781437  -3.370882273
 6  -0.789413035   6.688990116  -4.342286587
 6  -0.055111472   8.929401398  -3.849783897
 1   1.443504572   9.157564163  -2.329712868
 6   0.298076212   4.767425060  -3.243017673
 1  -1.401655316   5.980681419  -4.920276165
 1  -0.094206288  10.006113052  -4.071288109
 1  -1.565274358   8.440636635  -5.333720207
 1   1.504181743   3.204073906  -2.398009539
 1  -2.013802528   3.714172363   0.432187378
 1  -0.117557824   2.976899147   1.892080188
 1  -0.346732825   4.096096516  -3.829447031
 1  -1.008600593  -7.885177135  -0.743904114
 6  -1.296118617  -6.823998451  -0.701074123
 1  -3.382215738  -7.161512852  -1.107768655
 6  -2.592869759  -6.433920860  -0.866637707
 6  -0.596992493  -4.472844601  -0.510988414
 6  -2.959249020  -5.068047523  -0.684175551
 6  -0.273021400  -5.848994255  -0.511930227
 6  -1.981935859  -4.115353107  -0.315421581
 6  -4.312328815  -4.662028790  -0.883342803
 6   1.077417254  -6.264426708  -0.314257443
 6  -0.766512334  -2.541282177   2.116218328
 6   0.482969671  -3.534756422  -0.704156280
 6  -4.666359901  -3.355876923  -0.715304077
 1  -5.043920040  -5.415988922  -1.209794641
 1  -5.678107262  -3.001211166  -0.962754607
 6  -3.736554146  -2.426038742  -0.161308795
 6  -4.114409447  -1.064691544   0.019034149
 6  -2.446682692  -2.860499382   0.225868076
 6  -3.260683298  -0.190461308   0.628222644
 1  -5.091734409  -0.735273480  -0.363873065
 1  -3.498265266   0.881241798   0.701404989
 6  -2.067829609  -0.669742584   1.242238045
 6  -1.247334003   0.236688524   1.985994339
 6  -1.726443291  -2.035588026   1.161711097
 6   2.570476770  -1.665368199  -0.385892957
 6   0.360223055  -2.229899168  -1.301905990
 6   1.778499961  -3.949047089  -0.313777506
 6   2.808964968  -2.984159470  -0.124838896
 6   1.353652000  -1.271531701  -1.013472438
 6  -0.642843902  -1.877963781  -2.280822039
 6   2.058408260  -5.335773468  -0.127528667
 1   3.783469677  -3.323631048   0.256472379
 6   1.170880795   0.095211186  -1.396370411
 1   3.324805737  -0.895122170  -0.166672349
 1   1.295129657  -7.342193604  -0.278585762
 1   3.086189508  -5.633287907   0.128994450
 6  -2.541252136  -1.129064798  -4.237889290
 6  -0.788295269  -0.523271441  -2.673227787
 6  -1.415023446  -2.849833250  -2.964432240
 6  -2.340988874  -2.485913038  -3.919337034
 6  -1.770602107  -0.164156184  -3.627267838
 6   0.108272158   0.466699034  -2.159178734
 1  -1.256689072  -3.916919947  -2.742464066
 1  -2.927095175  -3.255744219  -4.442539215
 1  -1.893826008   0.898310602  -3.885324478
 1  -3.300484896  -0.852299988  -4.983394623
 6   1.083933234  -3.461144447   4.046145916
 6  -0.653575122  -3.919288397   2.426794291
 6   0.015092610  -1.628398776   2.868593931
 6   0.962880194  -2.110558271   3.803101063
 6   0.248277441  -4.369159222   3.368054628
 1  -1.313795328  -4.641179085   1.920832157
 6  -0.208976671  -0.221242979   2.735080004
 1   1.587736487  -1.384951472   4.345007896
 1   0.317308038  -5.442450047   3.598667383
 1   1.815424919  -3.836792707   4.775953770
 1  -1.481076002   1.310654163   1.930192590
 1   1.912659764   0.832148790  -1.053094149
 1  -0.061612576   1.518885136  -2.431946754
 1   0.449474514   0.468070835   3.284305096
ENDCART
FROZEN
ENDFROZEN
PI
ENDPI
PAIRING
ENDPAIR
HESSIAN
   13    3   13    3    3    3    3    3    3    3    3    3
    3   13   13    3    3    3    3   13   13    3    3    3
    3    3    3    3    3    3    3   13    3   13   13   13
    3    3    3    3    3    3   13   13   13   13    3    3
    3    3    3   13    3   13   13   13   13   13   13   13
   13    3   13    3    3    3    3    3    3    3    3    3
    3   13   13    3    3    3    3   13   13    3    3    3
    3    3    3    3    3    3    3   13    3   13   13   13
    3    3    3    3    3    3   13   13   13   13    3    3
    3    3    3   13    3   13   13   13   13   13   13   13
    1    2    1
    2    4    5
    2    7    5
    4    6    5
    6    8    5
    5    7    5
    5    8    5
    6    9    5
    8   18    5
    9   13    5
   16   18    5
   17   19    5
   19   22    5
   22   24    5
   18   24    5
   16   17    5
   13   16    5
    3    4    1
    5   12    5
    7   10    5
    9   14    1
   11   24    5
   13   15    1
   19   21    1
   22   23    5
   17   20    1
   12   27    5
   27   28    5
   25   28    5
   25   29    5
   26   29    5
   12   26    5
   28   32    1
   29   33    5
   25   34    1
   26   30    5
   27   31    5
   10   35    1
   31   36    1
   10   31    5
   30   39    5
   39   40    5
   37   40    5
   37   41    5
   38   41    5
   30   38    5
   40   44    1
   41   45    1
   37   46    1
   38   42    5
   39   43    1
   11   49    5
   49   50    5
   47   50    5
   47   51    5
   48   51    5
   11   48    5
   50   54    1
   51   55    1
   47   56    1
   48   52    1
   49   53    5
   33   42    5
   33   58    1
   42   59    1
   53   23    5
   23   57    1
   53   60    1
   61   62    1
   62   64    5
   62   67    5
   64   66    5
   66   68    5
   65   67    5
   65   68    5
   66   69    5
   68   78    5
   69   73    5
   76   78    5
   77   79    5
   79   82    5
   82   84    5
   78   84    5
   76   77    5
   73   76    5
   63   64    1
   65   72    5
   67   70    5
   69   74    1
   71   84    5
   73   75    1
   79   81    1
   82   83    5
   77   80    1
   72   87    5
   87   88    5
   85   88    5
   85   89    5
   86   89    5
   72   86    5
   88   92    1
   89   93    5
   85   94    1
   86   90    5
   87   91    5
   70   95    1
   91   96    1
   70   91    5
   90   99    5
   99  100    5
   97  100    5
   97  101    5
   98  101    5
   90   98    5
  100  104    1
  101  105    1
   97  106    1
   98  102    5
   99  103    1
   71  109    5
  109  110    5
  107  110    5
  107  111    5
  108  111    5
   71  108    5
  110  114    1
  111  115    1
  107  116    1
  108  112    1
  109  113    5
   93  102    5
   93  118    1
  102  119    1
  113   83    5
   83  117    1
  113  120    1
ENDHESS