Literature Seminar

2007.11.28 Shinya Handa (D1)Low Valent Ruthenium Catalyzed
Bond-Forming Reactions with Olefins
0 Introduction

Ru
The name derives from Ruthenia, the Latin word for Rus',a historical area which includes present-day Ukraine, Belarus,and parts of Russia, Slovakia, and Poland. Karl Klaus named
the element in honour of his birthland, as he was born in Tartu,
Estonia, which was at the time a part of the Russian Empire.
(from wikipedia in English)

CCMMCCσ donation

π back donation

Excellent reviews of Ru-Catalyzed reactions.
Trost, B. M. et al. Angew. Chem., Int. Ed. 2005, 44, 6630.
Mitsudo, T.-A. et al. Synlett 2001, 309.
Murahashi, S.-I. et al. Chem. Rev. 1998, 98, 2599.
Other examples (See below)· Dr. Suto's lit. seminar (2004.10.27); Direct substitution propargyl alcohol· Morimoto-kun's seminar (2007.11.21); Synergy of transition metal complex with acid/base catalyst

Contents
0 Introduction ··································· 1
1 Dimerization of 2.5-norbornadiene
1.1 History ····································· 2
1.2 Discovory ································ 2
1.3 Formation of Divalent Ruthenacyles·········· 4

2 Ruthenium aqua complex ························ 5
3 Codimerization ········································· 7
3.1 History
3.2 Ru Catalyzed reaction
4 Outlook & Remark ···································· 91/9

1 Dimerization of 2.5-norbornadiene
1.1 HistoryMetal-catalyzed [2+2] cycloaddition

Iridium: Osborn, J. A. et al. J. Am. Chem. Soc. 1973, 95, 598.
[Ir(cod)2Cl]22ca. 35% y.

+ COO

Nickel: Noyori, R. et al. J. Am. Chem. Soc. 1973, 95, 1674.
Ni(cod)2Ph3P+48% y.

Ruthenium: Mitsudo, T.-A. et al. J. C. S. Chem. Commun. 1976, 722.
E

E

RuH2(PPh3)4+Eup to 57% y.

E

1.2 Discovery

Mitsudo, T.-A. and Watababe, Y. et al. J. C. S. Chem. Commun. 1994, 435.
Mitsudo, T.-A. et al. J. Am. Chem. Soc. 1999, 121, 1839.

O
Me2N

CO2Me

DMMl

PCTD: pentacyclo[6.6.0.02,6.03,13.010,14]tetradeca-4-11-diene
HCTD: heptacyclo[6.6.0.02,6.03,13.04,14.05,9.010,14]tetradecane

orMeO2C

MeO2C

HCTD

PCTD

CO2Me

O

MeO2C

CO2Me
DMFm

c.f. dimerized product of nbd

Me2N
DMAc

4bicyclo[2,2,1]heptane
skeletone cannot be seen.
What the mechanism ??
· time course studyB

A + dmfm

A + dmml
Ainduction
timeA + dmfm
A + dmml

induction periodgeneration of B

3rd order dependency on nbd
1st order dependency on catalyst

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MeO2C

CO2Me60 °C, tol
CO2Me
Ru(cod)(cot)

MeO2Cyellow
macrocrystal

ARu(cot)(dmfm)2· Complexation with dimethyl maleate gave same crystal

bond lengthax: longer
eq: shorter

B

What 's the mechanism ??
but+ others
5%
2%
38%

45%

There is no evidence 3a is the precursor.
At least 2 C-C bond must be cleaved.

Proposed mechanism

required
several stepsc.f.) Ibers, J. A.et al
J. Am. Chem. Soc. 1981, 103, 3014.

tetravalent412561171187

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1.3 Formation of Divalent Ruthenacycles

Rη4RRuη2Ura, Y. Mitsudo, T,-A. et al. Organometallics 2006, 25, 2934.

bicyclodecane
ligand complex
η4

η4

1-2:5-6-η4

η6

Ambiguity of the hapticity contributed togiving unoccupied orbital

ruthenacycle

η41-4-η4
Mitsudo, T,-A. et al. Organometallics 2000, 19, 5733.

further treatment
with bidentate pligand did notgave isolable complex

X-lay structure of 5

Proposed mechanism
PPHE(dmfm)RuOOMe

sp2 C-Hactivation

POPEPinsertion

RuOMeOEOEPRuOOMeMeOHEOMe

5Personal Speculation
Why does interesting dimerization occur??
· sp2 C-H bond is activated due to the strain of the C-C double
and also creavage of C-C single bond occurred.

strainE· Ru-carbonyl oxygene interaction is essential?
Ru was directed to b-H and via 5 membered ring coordination,
sp2 C-H activation was promoted· Electron deficient olefin played key role to acceralate the reaction.
easy formation of Ru-H species

HRuOOMe
carbonyl direction· Coordinative solvent THF made interaction with Ru center.
In place of P ligand, sp2 C-H activation was prompted.

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2 Ruthenium Aqua Complex

Mitsudo, T,-A. et al. Organometallics 2002, 21, 4960.
Mitsudo, T,-A. et al. Organometallics 2005, 24, 5724.
rwdew poolleypale

H2O coordinated with Ru center.
Hydrogen bond with dmfm ligand.
RuInterestingly, dmfm ligand coordinated with Ru to same enantioface .
(re,re)&(re,re) or (si,si)&(si,si)

O7c.f.) Sustman. J. et al. J. Organomet. Chem. 1994, 470, 191.

4(re)

(si)

(re,re)meso

4a(re,re)(re,re)chiral

H2O

O14b(re,re)(si,si)(si,si)4a4bη6

η4

7 was isolated in the case of dppm.
7-dppm was intact with H2O and extra
P ligand.

see page 4

Characters of Ru aqua complex 4
1HNMR

H2O δ 4.68

sharper

Shoulderappeared.

rather broad&split

geminal two protonsof H2O are nonequivalent(1) At –40 °C, peak corresponding toH2O became sharp temporary.
(2) Under -70 °C two different peaks ofH2O appeared. (split)

At higher temperature, H2O is equivalent.
That is because...
(1) rotationor(2) exchange with outer H2O

experimental calculated

Scheme 1. Possible positional exchange process of the water protons
via rotation and inversionµ3-oxotetraruthenium cluster

Kondo, T. and Mitsudo, T.-A. et al
J Organomet. Chem. 2007, 692, 530.

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DFT calculations
lose 2 hydrogen bonds

gain 2 hydrogen bonds
longerlongerinteraction
widerrotate

Rotation of H2O isenergetically favorable.

Exchange ofouter H2OWhat is the shoulder peak at –40 °C.

H2OERuERuMeOOHH2OOflipO

30.8 kcal/mol

OH

18 kcal/mol
OMe

H2O

H2O

8.5 kcal/mol
unstabledissociative

associative

Metal aqua complex as an asymmetric catalyst（物思いにふけってみました）(1) chiral center is close to the substrates
Effectively enantio-induction occurs?!

(2) different kinds of interactions of substrates
Wider ranges of substarates are applicable.
metal coordination

substrate
coordinationsitechirality

chirality(1) Examples of (S)-QUINAP complex(S)-QUINAPClCH2CH2Cl60 °C

hydrogen bondingchirality induction
PPh3Low yield should be solved.
Application to other metals
chiralitytransfer

N(S)-QUINAP

29% y.

(2) multifuctional complex

LiOO
O
La
LiOO
O
Li

combinations ofLewis Acid
Lewis BaseX
Brønsted Acid
Brønsted Base
· LiOH

image

*PCRu
H

*O
2nd generation LLB

NP

E

H
H

O

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3 Codimerization of Olefins

Reviews

3.1 History

Gooßen, L. J. Angew. Chem., Int. Ed. 2002, 41, 3775.
RajanBabu, T. V. Chem. Rev. 2003, 103, 2845.
Gooßen, L. J. et al. Angew. Chem., Int. Ed. 2007, 46, 7544.

Alderson, T.; Jenner, E. L.; Lindsey, R. V. Jr. J. Am. Chem. Soc. 1965, 87, 5638.
H2C

CH2

RhCl3·H2O

H3C

CH3400 atm

CH3+78%+H3C
20%

2%

Nickel-hydride catalyzed reactionc.f.) Brookhart, M. at al. J. Am. Chem. Soc. 1997, 119, 906
and references therein.

And also regioselectivity from the view of kinetic and thermodynamic
controles, see Handa's lit. Seminar 060715 Pd catalyzed oxidative reactions[Ni]-Hη3-intermediate3.2 Low Valent Ru Catalyzed Reaction
Mitsudo, T.-A. et al. J. Org. Chem. 2005, 70, 6623.

tpy=NNN

RuIII catalyst itself had no activity.
dissociation of arene was difficult
proposed mechanisms

red. elim.

β-elim.
ruthenacyclopentane

zerovalent

Ru0 is the active species.
Alcohol is not necessary for dimerization.

catalyst 3 wasutilized.

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Also other mechanism can be thought. (Path C: one candidate)
sp2 C-H
activation

Path Bβ-H elimination from 7 cannot be explained predominat
formation of trans-isomer.
How did active catalys [Ru]-H generated ??

red. elim.

Path CHPath C
After the C-H activation cis-isomermight be more stable?

[Ru]O

H [Ru]CO2R

CORinsertion

Kondo, T. et al. Angew. Chem., Int. Ed. 2007, 46, 5958.

· no reaction occurred with divalent Ru complex.
· linear adduct formed with (E) C=C double bond.
· Primary alcohol is essential (3 equiv.).
Time course study(parehthasis is isolated yield)

What is the role of alcohol ?
· Primary alcohol is essential(1-propanol, 1-octanol and ehanol)
Secondary, tertiary alcohol is not suitable.
Alcohol interacted with Ru complex.

induction periodalmost no [D2]-2a or [D3]-2aGeneration of [Ru]-H which rapidly reacted with styrene
and the product was intact to the active species.

red. elim.
insertion[Ru]

alocohol played nothing.
active species
β elim.
insertion[Ru]should be
predominant

ruthenacyclopentane

acceleration of reaction
ordirect other pathway

D distribution cannot be explained

Authers suggested path C. However, the observed phenomina is imcompatible.

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Is path B the most reasonable mechanism??

rapid equilibrium[Ru]-H was generated Ru and alcohol.

[Ru]· induction period ······· O· D distribution ······ ?
· regioselectivies ······· O[Ru]kinetic

thermodynamic

Further mechanistic study is required.

c.f.) Stahl, S. S. et al. J. Am Chem Soc. 2005, 127, 17888.

Ura, Y., Kondo, T. et al. Angew. Chem., Int. Ed. 2007, 46, 5160.

[6+2] cycloaddition
consumed the substrate some extent.

condition B································

PdB

AA'B'

Ru········

reaction condition························

condition A

catalytic activity

3 Outlook & Remark

Ru-catalyzed reactions
Reactivities, substrate scopes

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