A new asymmetric grignard cross-coupling reaction via an alkyl group isomerization catalyzed by chiral phosphine-nickel complexes

No. 21, pp 1799 - 1802, 1977. Pergamon Press.

Tetrahedron Letters

Printed

in Great Britain.

A NEW ASYMMETRIC GRIGNARD CROSS-COUPLING REACTION VIA AN ALKYL GROUP ISOMERIZATIONCATALYZED BY CHIRAL PHOSPHINE-NICKFLCOMPLEXES

Takaya Mise and Makoto Kumada*

Michio Zembayashi, Kohei Tamao, Tamio Hayashi, Department of Synthetic

We have previously

plexes

Faculty

of hzgineering,

in Japan 2 Maroh 1977; received

(Received

halides

Chemistry,

reported

to give optically as catalysts,

active

hydrocarbons

as exemplified

PhMeCHMgCl

that set-alkyl

7 April

in LX for publication

Grignard reagents in the presence

by the following

react

Kyoto 606, Japan

1977)

with aryl and alkenyl

of chiral

phosphine-nickel

com-

reaction.1*2 H

[Ni-P*]

CHz= CHBr

+

Kyoto Univemity,

L

CHz=CH-L*-Me

(13

I

Ph

This asymmetric coupling kinetic

resolution

Recently alkenyl

reacts

nickel

group isomerization

in 48% yield,

anticipated

complex-catalyzed

together

should afford

CHz= CHCH2CH2Br

+

of

optically

PhMgBr -

[Ni-P*]

isomeric

as a catalyst

butenylbenzenes.6 of any chiral

as

to give 3It was

phosphine-

3-phenyl-1-butene. H CHz=CH-:*-Me &l

1799

of $-

For example, 4-bromo-1-butene

in the presence active

reaction3

benzenes predominantly,

[Ni(dppp)C1z15

with other possible reaction

coupling

alkenyl

from primary to secondary.4

that such a coupling

complex as catalyst

but as a

Grignard reagents.

phenylmagnesium bromide in the presence

phenyl-1-butene therefore

set-alkyl

not as a true asymmetric synthesis

with a phenyl Grignard reagent gave secondary

of alkyl with

of racemic

is classified

we have found that a nickel-phosphine

halides

a result

reaction

(2)

No. 21

1800

This reaction provides a new type of asymmetric synthesis in which the achiral halide is converted into a chiral'moiety by the action of a chiral catalyst. It should be also noted that these two different types of asymmetric reaction, (1) and (Z), give the same chiral product, which allows us to evaluate stereochemistryof the reaction intermediatesmore precisely. The asymmetric synthesis could actually be achieved by the use of the following chiral phosphines as ligands. H e iEl C--F!Me2

PPhz PPh2

PPh2

(R)-(S)-BPPFA7

(R)-(S)-PPFA7

H

(R)-(S)-BPPFOH*

(-)-DIOPy

Typical procedure is as follows. An ethereal solution of phenylmagnesiumbromide (1.2 equiv) was added to an ethereal solution of 4-bromo-l-butene (A) (1 equiv) in the presence of an equimolar mixture of NiC12 and (R)-(S)-BPPFA (0.5 mol %). The mixture was refluxed for 46 hr.

Glc

analysis after usual work-up showed that 3-phenyl-1-butene (2) was formed in 58% yield,based on 5, along with 17% yield of (Z)-l-phenyl-2-buteneand trace amounts of 4-phenyl-1-buteneand (E)1-phenyl-2-butene. Lwas

isolated by preparative glc and was found to be optically active,

[a]E2 -2.16O (neat), corresponding to 33.8% optical yield of the R isomer. Results are summarized in Table 1. It seems of interest to compare the present results with those obtained from reaction (1). Firstly, optical yields attained by the present reaction are about one half or less of those obtained by reaction (1) for each chiral phosphine ligand.1>29'0 With respect to stereoselectivity, ferrocenylphosphinesare much more effective ligands than DIOP. Secondly, these two types of asymmetric coupling reaction give the enantiomeric products in the presence of the same chiral phosphine ligand; e.g., with (S)-(R)-BPPFAas a ligand (R)-(-)-&

is obtained from reac-

tion (l), while reaction (2) forms (S)-(+)-& These features may be rationalized by Scheme 1. Thus, according to the mechanism proposed for the nickel-phosphinecomplex-catalyzedGrignard cross-coupling reaction,3 chiral diorganonickel complexes2 andz are believed to be involved as crucial intermediates in the reactions (1) and (2), respectively. The fact that these two reactions give enantiomeric coupling products clearly indicates that both the intermediates contain the chiral carbon center of the same

No.

1 a01

21

Table

Asymmetric

1.

in the

Cross-Coupling

Presence

of

Reaction

Chiral

of

4-Bromo-l-butene

Phosphine-Nickel

with

Complexes

Phenylmagnesium

Bromide

as Catalysts’

3-Phenyl-1-butene

(A)

Ni catalystb Yield

Predominant d (% ee)

(neat)

28

-0.6ge

R

(5.7)

NiClz-

(R)- (S)-BPPFA

58

-2.16

R

(33.8)

NiClz-

(S)- (R)-BPPFA

58

+2.14

s

(33.4)

NiClz-

(R)- (S)-BPPFOH

24

-0.91

R

(14.2)

16

+1.21

s

(18.8)

a Catalyst/4-bromo-1-butene/PhMgBr the

ligands,

see

Maximum rotation

&em.

SOC.,

absolute these the

[a],22

[Nit (-)-DIOP)C12]

NiClz-2(S)-(R)-PPFA

of d

(%)’

2,

the of

2141

text.

(1952).

were

determined

The major

vinyl

[a];2

ee = Enantiomeric

part

may be attributable

one hand and the

Scheme

c Yields

Refluxed

(R)-(-)-3-phenyl-1-butene;

configuration. two reactions

= 5~10-~/1/1.2.

group

on the

excess.

for

by glc -6.39“

based

on the D. J.

e Benzene

the

observed

differences

to

the

different

bulkiness

attached

to

the

b For the

(neat):

of

other,

46 hr.

configuration

solution

in

organic Cram, J. (c

the

carbon

phenyl

center.

1 H Me, :c,Ph C [Ni-P*] 1

-I

Iw P* - Ni -CH=CH2

L.-

-

W-(-,-L

c p*’ ??. H Me, $cH=CH, C [Ni-P*] ?.

+

z-

Iw

P*-Ni-Ph

cp*/

-

halide

(k).

Amer.

2.9).

stereoselectivity

between

chiral

abbreviation

(S)- (+)-A

between group

on

No.

1802

A mechanism nickel

the

intermediate

merizes

to

pling

of

isomerization

arising

a chiral

formation

the

e.g.,

briefly

oxidative

discussed addition

a-1-methyl-2-propenyl-nickel

a butadiene-hydrido-nickel

faster

because

is

from the

productzdemonstrates

proceeds

in,

for

than

latter

that

the

of

coupling

isomerization

would

coupling

the

give

of

achiral

butadiene

of Ato

intermediate

complex. of

the

(cf.

L),

the

moieties

two organic group

via

coupling

catalyzed

nickel

possibly

formation

butenyl

formed

a low valent

The predominant

non-branched

and ethylene

An initially

here.

in the

n-allylic

products

the

nickel

iso-

transient chiral

cou-

intermediateL intermediates,

predominantly,

by nickel-hydride

3-butenyl-

species

via

of

21

as observed

complexes.ll

ACKNOWLEDGEMENTS

We thank and 985156) this

the

Grant-in-Aid

and Nitto

Institute

for

Scientific

of

Chemical

Research Research

of

the

Ministry

Ltd.

Co.,

for

of

Education

partial

(No.

financial

110305

support

of

work. REFERENCESAND NOTES

1.

Y. Kiso, also

K. Tamao,

G. Consiglio

2.

T. Hayashi,

3.

K. Tamao, Minato

4.

This

N. Miyake, and C.

Y.

Kiso,

and M. Kumada, Bull. is

the

secondary

in the

tion

secondary

from

Hezu.

first

M. Zembayashi,

Chem. Sot. example

nickel-phosphine to

primary

of

A.

Fujioka,

S.

Jpn., 49, 1958 (1976) the

alkyl

group

complex-catalyzed has been

Kumada, J. Amer. Chem. Sot., 2,

see

Chim. Acta, 56, 460 (1973).

K. Tamao and M. Kumada, J. Amer. Ckem. Sot., 98, 3718

M. Tajika, K. Sumitani,

reaction

K. Yamamoto and M. Kumada, Tetrahedron Lett., 3 (1974);

Botteghi,

K. Tamao,

Y.

I.

Kiso,

while

A.

cited

from primary

coupling, Y.

(1976).

Nakajima,

and references

isomerization

Grignard

observed:

9268 (1972);

Kodama,

the

K. Sumitani

therein. to isomerizaand M.

K. Tamao and M. Kumada, J. Organ+

Kiso,

metal. Chem., 50, Cl2 (1973). 5.

dppp = PhzP(CHz) 3PPh2.

6.

Yields

7.

T.

a.

T. Hayashi,

9.

H. B. Kagan and T.-P.

of

(1.5%),

10.

the

isomeric

products

and (E)-CH$H=CHCHzPh

Hayashi,

We have

lished

T. Mise

additional

Tolman,

1996

CH2=CHCH2CH2Ph (1.5%)

, (2) -CH3CH=CHCH2Ph

(12%).

and M. Kumada, Tetrahedron Lett., 4351 (1976). Dang, J. Amer. Chem. Sot., 94, 6429 (1972).

experimental purity:

results

showing

T. Hayashi,

that

(S)-(R)-BPPFA

M. Tajika,

as

ligand

affords

(R)-

K. Tamao and M. Kumada, unpub-

results.

R. G. Miller,

177

as follows:

K. Yamamoto and M. Kumada, Tetrahedra Lett., 4405 (1974).

(-)-2 of up to 60% optical 11.

are

T. J.

ibid., z,

(1972); (1972).

Y.

Kealy

and A.

6777 (1970);

Inoue,

T.

Kagawa,

L. Barney, A. C.

J. Amer. Chem. Sot., 89, 3756 (1967);

L. Su and J.

Y. Uchida

W. Collette,

and H. Hashimoto,

C. A.

J. Orgarwmetal. Chem.,

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