Subject: SUMMARY: TM oxidative addition/reductive elimination to the C-C bond

From: "Ananikov V.P." <[email-masked]>
Date: Sun, 29 Jun 1997 23:12:39 -0700

Dear All,

Here is my original request and replies obtained on question I have
asked last week. I thank to: 
    Alexander A.Bagatur'yants [email-masked]
    Ole Swang  [email-masked]
    Georg Schreckenbach [email-masked]   
    Seiji Mori [email-masked]
for the helpful information.

Any additional comments?

all the best,
Valentin.
 
Valentin P. Ananikov
NMR Laboratory
N.D. Zelinsky Institute of Organic Chemistry
Leninsky Prospect 47
Moscow  117913
Russia
e-mail: [email-masked]
Fax     (095) 135 5328 
Phone   (095) 135 9094, (095) 938 3536

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 Subject: CCL:TM oxidative addition/reductive elimination to the C-C
bond
 Date: Tue, 24 Jun 97 04:14:23 +0300
 From:"Ananikov V.P." <[email-masked]>
 To: [email-masked]

Dear All,

         I would like to know if anyone have an experience in reaction 
pathway calculations of Transition Metals insertion(oxidative addition) 
to the C-C bond and corresponding reverse process(reductive elimination) 
as well.  There are many examples of TM addition to H-H, C-H, Si-H
bonds, 
but only a few references concerning C-C bond breaking/forming by TM 
complexes.  

Does ECP provide sufficient accuracy level for these calculations?
How important are electron correlation and relativistic effects on third 
row elements?

In case of insertion to the X-H bond the reactions were found to proceed 
through three-centered transition state, i.e.:

                                 X  - H
                                  \  /
                                   TM

Is it correct to guess the same transition state structure for insertion 
to the C-C bond?

your suggestions/references are welcome!

I will summarize.

thank you.

                                    sincerely yours,
                                    Valentin.

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reply 1
__________________________________________________________________________
  Subject: Re: CCL:TM oxidative addition/reductive elimination to the
C-C bond
  Date:  Tue, 24 Jun 1997 15:34:11 +0100
  From: "Alexander A.Bagatur'yants" <[email-masked]>
  Organization: Center on Photochemistry, Russian Academy of Sciences,
Moscow
                 Russia
  To: [email-masked]

Dear Valentine,
Many years ago, I was involved in this kind of activity (I mean
catalysis by transition metal complexes. There have been a lot of
articles published on this topic during last years. As to the problem
that you are interested in, the publications are rather limited, partly
because the number of experimental papers on this matter is also very
limited. In addition, the experiment is not easy to interpret in this
case. I can remember some papers of Roald Hoffmann, A. Weillard, A.
Dedieu, and, may be, you should look through papers of P. Siegbann, U.
Wahlgren, or M. Blomberg.
As to the mechanism, It could be rather diversified. Though the first
idea is this three-center transition state, we can imagine something
like a multistep process through some more plausible structures such as
addition through a C-H bond and then a transformation to a carbenoid
structure, and then a rearrangement in the coordination sphere of the
transition metal, or something else. I would like to discuss these
matters when in Moscow (I will return home on this weekend and then be
there till the end of August.
Sincerely yours
A. Bagatur'yants 

********************************************************************
* Prof. Alexander A. Bagatur'yants   Phone: (007)-(095)-9362588    *
* Center on Photochemistry           Fax:   (007)-(095)-9361255    *
* Russian Academy of Science                (007)-(095)-4335325    *
* ul. Novatorov 7a, Moscow           E-mail  [email-masked] *
* 117421 RUSSIA                              [email-masked]  *
********************************************************************
__________________________________________________________________________

reply 2
__________________________________________________________________________
  Subject: Re: CCL:TM oxidative addition/reductive elimination to the
C-C
           bond
  Date:  Tue, 24 Jun 1997 17:37:57 +0200
  From:  [email-masked]
  To:   <[email-masked]>

Dear Valentin,

For C-C bond oxidative addition to TM atoms, see M. R. A. Blomberg et
al., 
J. Am Chem. Soc. 113 (1991) 424.

Good luck,

Ole Swang
----------------------------------------------------------------
Ole Swang                        Research scientist, Dr. Scient.
SINTEF Applied Chemistry, Dept. of Hydrocarbon Process Chemistry
POB 124 Blindern, N-0314 Oslo, Norway.      Phone: +47 2206 7429 
Email: [email-masked]               Fax: +47 2206 7350
URL: http://www.sintef.no/units/chem/6630/ole.html
------------------  ._.. ._ ..___ ._ __..  ---------------------
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reply 3
__________________________________________________________________________
   Subject: Re: CCL:TM oxidative addition/reductive elimination to the
C-C
           bond
   Date: Tue, 24 Jun 1997 09:15:08 -0700
   From: [email-masked] (Georg Schreckenbach)
   To:   <[email-masked]>

Hi Valentin,

only a partial answer to your rather general question.

>Does ECP provide sufficient accuracy level for these calculations?

I don't see why ECP shouldn't be good enough, as long as you choose your
ECP, basis set, etc. carefully.

>How important are electron correlation and relativistic effects on third
>row elements?
Relativistic effects are, in my opinion, essential for the third
transition row,
also important for the second, but usually you can well do without for
the
first row of transition metals (so it depends on what you mean by "third
row").
The use of relativistic ECPs is a well established and valid
relativistic
method.
   Correlation effects are typically equally crucial for the transition
metal
complexes. That's part of the reason why DFT is so popular for them.

Best reagrds, Georg

P.S. Please summarize!

--
==============================================================
Dr. Georg Schreckenbach           Tel:     (USA)-505-667 7605
Theoretical Chemistry T-12        FAX:     (USA)-505-665 3909
M.S. B268, Los Alamos National      E-mail:  [email-masked]
Laboratory, Los Alamos, New Mexico, 87545, USA
==============================================================
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reply 4
__________________________________________________________________________
  Subject: CCL:TM oxidative addition/reductive elimination to the C-C
bond
    Date:  Wed, 25 Jun 1997 08:53:42 +0900 (JST)
    From: [email-masked] (Seiji Mori)
      To: [email-masked]
      CC: <[email-masked]>

Dear Dr. Ananikov:

I have experiences of C-C bond forming process you said as to
organocopper
case .

In the reductive elimination from Me3Cu(Me2O) and Me3Cu(H2O), Dorigo and
Schleyer
 (Angew. Chem. Int. Ed. Engl. 1995, 34, 476)
and Snyder (J. Am. Chem. Soc. 1995, 117, 11025)  show three-centered
transition state
using all-electron basis set and ECP, respectively.
Snyder's ECP results are good agreement with Dorigo's AE results.

We (Nakamura, Mori, Nakamura, Morokuma, JACS, 1997, 119, 4887 and
Nakamura, Mori, Morokuma, JACS, 1997, 119, 4900) also have shown that
in the case of organocopper reaction with acetylene and acrolein.
In the acetylene addition, the geometry using relavistic ECP using Dolg
et
al. are found to be
essentially the same as that using AE. (As to second and third-row TM,
relavistic effects
are not small. See. Pyykko, Chem. Rev. 1988, 88, 563.)

  In the paper on the conjugate addition to acrolein, we showed TSs in
the
oxidative addition
 and reductive elimination.
The oxidative addition TS can be viewed as three-centered.
Reductive elimination TS can be viewed as not only three-centered but
also
four-centered.

I hope my comment is your help.
Sincerely yours,
 Seiji Mori

###################################################
~  Seiji Mori.(M.Sc.)
~
~  Graduate student
~  Lab. of Physical Organic Chemistry, Department of Chemistry
~  The University of Tokyo
~  Hongo 7-3-1, Bunkyo-ku, Tokyo 113, JAPAN.
~  email:[email-masked]
~  TELE FAX：　　+81-3-3812-8099
: -)  ---
‾ http://www.chem.s.u-tokyo.ac.jp/Students/smori.html
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