Polynuclear metal complexes linked by conjugated pyridines

Journal of Organometallic Chemistry 564 (1998) 257–266

Jiann T. Lin ^a,*, Ming-Fa Yang ^b, Chiitang Tsai ^b, Yuh S. Wen ^a

^aInstitute of Chemistry, Academia Sinica, Nankang, Taipei 115, Taiwan, ROC

^bDepartment of Chemistry, Chinese Culture Uni6ersity, Taipei, Taiwan, ROC

Received 1 April 1998; received in revised form 12 May 1998

Abstract

The alkyne entity in 4,4%-dipyridylbutadiyne (DPB), 1,4-bis(4%-pyridylethynyl)benzene (BPEB), (4-aminophenyl)-4%-pyridy-

lacetylene (APPA), ferrocenyl-4-pyridylacetylene (FPA) and 1,6-diferrocenyl-3-ene-1,5-hexadiyne (DFEHD) can be readily ligated

to Cp₂Mo₂(CO)₄and ‘Co₂(CO)₆’, derived from Co₂(CO)₈. Both alkyne and pyridine entities in DPB or BPEB can be ligated to

metal carbonyls, and (v₄-p^1:1:2:2-DPB)[W(CO)₅]₂[Cp₂Mo₂(CO)₄] (11), (v₄-p^1:1:2:2-BPEB)[W(CO)₅]₂[Cp₂Mo₂(CO)₄] (12), (v₆-

p

^1:1:2:2:2:2-BPEB)[W(CO)₅]₂[Cp₂Mo₂(CO)₄]₂

(13),

(v₆-p^1:1:2:2:2:2-BPEB)[W(CO)₅]₂[Co₂(CO)₆]₂

(14),

and

(v₆-p^1:1:2:2:2:2

-

BPEB)[W(CO)₅]₂[Cp₂Mo₂(CO)₄][Co₂(CO)₆] (15) were isolated. There exist semibridging carbonyl ligands in complexes which

Keywords: Polynuclear; Metal complexes; Conjugated pyridines

1. Introduction

complexes are popular among coordination com-

pounds, such conjugated pyridines should be useful

building blocks for polynuclear multi-metal complexes.

In this report, we will describe several multi-metal

complexes assembled by conjugated pyridyl ligands.

Some complexes derived from conjugated biferrocene

are also included for spectroscopic comparison.

Metals in close proximity have potential to exhibit a

cooperative effect which is useful in catalysis [1]. While

quite a few ligands, such as phosphido, sulﬁdo and

amino, are capable of bringing two metal fragments

closer [2], construction of polynuclear complexes is

generally facilitated by the use of polydentate ligands

[3]. Polydentate ligands containing alkyne entities have

been successfully used to assemble several metal moi-

eties [4] exploiting the ligating capability of alkynes [5].

It also appears to be interesting that the electronic

communication between two metal centers, linked by

the conjugated chain containing alkyne entity, is not

quenched upon ligation of the alkyne entity to metal

carbonyls ([4]a). Recently, we are interested in conju-

gated pyridyl ligands incorporating an alkyne entity [6]

owing to their usefulness in the preparation of

organometallics nonlinear optical materials [7] and

organometallic polymers [8]. Since metal pyridine [9]

2. Experimental section

2.1. Materials and apparatus

All reactions and manipulations were carried out

under N₂with the use of standard inert-atmosphere and

Schlenk techniques. Solvents were dried by adoping

standard procedures. Column chromatography was

performed under N₂with the use of silica gel (230–400

mesh ASTM, Merck) as the stationary phase in a

column of 35 cm length and 2.5 cm diameter. 4-

Ethynylpyridine [10], 4,4%-dipyridylbutadiyne (DPB) [6],

1,4-bis(4%-pyridylethynyl)benzene (BPEB) [6], (4-

aminophenyl)-4%-pyridylacetylene (APPA) [6], ferro-

* Corresponding author. Fax: +886

jtlin@chem.sinica.edu.tw

2

27831237; e-mail:

PII S0022-328X(98)00701-3

258

J.T. Lin et al. / Journal of Organometallic Chemistry 564 (1998) 257–266

cenyl-4-pyridylacetylene (FPA) [6], and Cp₂Mo₂(CO)₄

[11] were prepared by published procedures. IR mea-

surements were measured on a Perkin-Elmer 880 spec-

trometer. The NMR spectra were measured by using

Bruker AC200 and AC300 spectrometers. Mass spectra

2.3. (v₂-p^2:2-PY)[Cp₂Mo₂(CO)₄] (2, L=APPA; 3,

L=FPA)

Complexes 2 and 3 were synthesized by the same

procedure as used for 1 except that APPA and FPA

were used instead of DPB.

(FAB) were recorded on

spectrometer.

a

VG70-250S mass

Purple complex 2 was eluted with THF/hexane (1:3)

in a 46% yield. MS (FAB): m/e 627 (M⁺). Anal.

Found: C, 51.38; H, 3.02; N, 4.32. C₂₇H₂₀N₂O₄Mo₂.

Calc.: C, 51.61; H, 3.21; N, 4.46%.

2.2. (v₂-p^2:2-DPB)[Cp₂Mo₂(CO)₄] (1)

Orange complex 3 was eluted with THF/CH₂Cl₂(1:9)

in a 35% yield. MS (FAB): m/e 720 (M⁺). Anal.

Found: C, 51.40; H, 3.11; N, 1.72. C₃₁H₂₃NO₄FeMo₂.

Calc.: C, 51.62; H, 3.21; N, 1.94%.

To a ﬂask containing a mixture of Cp₂Mo₂(CO)₄

(1.00 g, 2.30 mmol) and DPB (0.47 g, 2.30 mmol)

was added 200 ml of CH₂Cl₂, and the solution

reﬂuxed for 24 h. The solvent was removed in vac-

uum, and the residue was chromatographed. Elution

with CH₂Cl₂/hexane (1:3) gave a purple band from

which the powder 1 was isolated in 74% yield (1.09

g) after removal of the solvent. MS (FAB): m/e

637 (M⁺). Anal. Found: C, 52.65; H, 2.60; N,

4.26. C₂₈H₁₈N₂O₄Mo₂. Calc.: C, 52.68; H, 2.84; N,

4.39%.

2.4. (v₂-p^2:2-BPEB)[Cp₂Mo₂(CO)₄] (4) and

(v₄-p^2:2:2:2-BPEB)[Cp₂Mo₂(CO)₄]₂(5)

Complexes 4 and 5 were synthesized by the same

procedure used for 1 except that BPEB was used in-

stead of DPB. Elution of the residue with THF/CH₂Cl₂

(1:9) gave an red band from which the powder 4 was

Table 1

Crystal data for compounds 1, 2·THF, 9 and 13

1

2·THF

9

13

Formula

C₂₈H₁₈N₂O₄Mo₂

638.33

8.809(2)

9.280(1)

16.237(3)

85.31(2)

C₃₁H₂₈N₂O₅Mo₂

699.44

9.026(1)

9.915(6)

16.878(5)

87.83(4)

C₄₀H₃₀O₂Fe₂Mo₂

878.25

14.243(2)

9.498(1)

25.178(2)

—

C₂₉H₁₆NO₉Mo₂W

898.18

8.597(2)

29.746(7)

11.7181(9)

—

Formula weight

˚

a (A)

˚

b (A)

˚

c (A)

h (°)

i (°)

k (°)

75.65(2)

72.52(1)

79.36(2)

72.75(2)

101.386(8)

—

94.09(1)

—

Crystal system

Space group

Triclinic

Monoclinic

P2₁/n

4

3339.1(6)

1.747

Monoclinic

P2₁/c

4

2989(1)

1.996

(

P1

2

P1

2

Z

3

˚

V (A )

1226.5(4)

1.729

1418(1)

1.639

D_calc.(g cm⁻³

)

Crystal size (mm)

Radiation Mo–K_h(A)

v (mm⁻¹

0.20×0.14×0.28

u=0.7107

1.01

0.10×0.14×0.28

u=0.7107

0.87

0.38×0.22×0.25

u=0.7107

1.61

0.38×0.09×0.16

u=0.7107

4.78

˚

)

Transmission factors

(max–min)

1.00–0.93

1.00–0.86

1.00–0.94

1.00–0.69

2q range (°)

Octants

2.0–45

−85h59, 05k59, −

175l517)

2.0–50

−95h59), 05k510, −

175l518

2.0–45

−155h515, 05k510),

05l527

2.0–45

−95h59, 05k532, 05

l512

No. of unique reﬂections 3211

3694

4350

4565

No. of reﬂections with

I\n|

2597 (n=2)

2859 (n=2)

3557 (n=2.5)

3107 (n=2)

No. of variables

326

0.026, 0.028

1.43

318

0.047, 0.055

2.70

433

0.027, 0.033

1.60

379

0.036, 0.037

1.50

R^a, Rw^b

GOF

Max D/|

0.002

0.001

0.121

0.004

^aR=SꢀF_oꢁ−ꢁF_cꢀ/SꢁF_oꢁ. ^bRw=[Sw(ꢁF_oꢁ−ꢁF_cꢁ)²/SwꢁF_oꢁ²]^1/2; w=1/[|²(F_o)+0.0001F²_o]. For 1 k=0.00005, 2·THF k=0.00005, 9 k=0.0001 and 13

k=0.0001.

J.T. Lin et al. / Journal of Organometallic Chemistry 564 (1998) 257–266

259

(FAB): m/e 851 (M⁺). Anal. Found: C, 45.25; H, 1.29;

N, 3.45. C₃₂H₁₂N₂O₁₂Co₄. Calc.: C, 45.10; H, 1.15; N,

3.29%.

Table 2

Atomic coordinates for complex 1

Atom

x

y

z

B_iso

Mo1

Mo2

O1

O2

O3

O4

N1

N2

C1

C2

C3

C4

C5

C6

C7

C8

C9

C10

C11

C12

C13

C14

C15

C16

C17

C18

C19

C20

C21

C22

C23

C24

C25

C26

C27

C28

0.39833(5)

0.10838(5)

0.6282(5)

0.1862(6)

0.2660(5)

0.0241(5)

0.3167(6)

0.9264(7)

0.5440(7)

0.2615(7)

0.2078(7)

0.0706(6)

0.4050(7)

0.3973(6)

0.2904(5)

0.1959(6)

0.2113(7)

0.2867(5)

0.3662(5)

0.4790(6)

0.5742(6)

0.6923(6)

0.8300(7)

0.9416(8)

0.7956(9)

0.6762(7)

0.5652(8)

0.6432(7)

0.5477(9)

0.4112(8)

0.4199(8)

0.91391(5)

1.15009(5)

0.9789(5)

0.8587(5)

1.0945(4)

0.8447(4)

1.4036(5)

1.3876(7)

0.9556(6)

0.8834(6)

1.1096(6)

0.9509(6)

1.4072(6)

1.3329(6)

1.2452(5)

1.2400(5)

1.3211(6)

1.1558(5)

1.1408(5)

1.1991(5)

1.2433(5)

1.2940(5)

1.1929(6)

1.2439(8)

1.4841(7)

1.4445(6)

0.6688(6)

0.7597(7)

0.8175(6)

0.7636(6)

0.6740(6)

1.4108(6)

1.3585(7)

1.2560(7)

1.2455(6)

1.3402(7)

0.78425(3)

0.74811(3)

0.8862(3)

0.9629(2)

0.5554(2)

0.7748(3)

1.0192(3)

0.4285(3)

0.8492(4)

0.8987(3)

0.6273(3)

0.7652(3)

0.9403(4)

0.8724(3)

0.8852(3)

0.9671(3)

1.0299(3)

0.8155(3)

0.7307(3)

0.6718(3)

0.6168(3)

0.5538(3)

0.5073(3)

0.4471(4)

0.4731(5)

0.5364(4)

0.7678(4)

0.7074(4)

0.6489(3)

0.6712(4)

0.7453(4)

0.7649(5)

0.7047(4)

0.7452(4)

0.8317(3)

0.8438(4)

2.71(2)

2.40(2)

6.7(3)

6.6(3)

5.3(2)

5.6(2)

4.5(3)

6.2(3)

4.2(3)

3.8(3)

3.4(3)

3.7(3)

4.5(3)

3.3(3)

2.3(2)

3.3(3)

3.9(3)

2.3(2)

2.4(2)

2.5(2)

3.0(3)

2.7(2)

3.9(3)

5.6(4)

6.5(4)

4.8(3)

4.9(3)

5.5(3)

5.0(3)

4.8(3)

4.6(3)

5.0(3)

4.5(3)

4.3(3)

4.0(3)

4.6(3)

2.6. (v₄-p^2:2:2:2-BPEB)[Cp₂Mo₂(CO)₄][Co₂(CO)₆] (7)

Complex 7 was synthesized by the same procedure as

used for 6 except that complex 4 was used instead of

BPEB. Dark brown complex 7 was eluted with THF/

CH₂Cl₂(2:3), resulting in an 18% yield. Anal. Found: C,

47.82; H, 2.14; N, 2.77. C₄₀H₂₂N₂O₁₀Co₂Mo₂. Calc.: C,

48.03; H, 2.22; N, 2.80%.

2.7. 1,6-Diferrocenyl-3-ene-1,5-hexadiyne (DFEHD)

(8)

Complex 8 was isolated as a minor product (10%)

Table 3

Atomic coordinates for complexes 2·THF

Atom

x

y

z

B_iso

Mo1

Mo2

O1

O2

O3

O4

N1

N2

C1

C2

C3

C4

C5

C6

C7

C8

C9

C10

C11

C12

C13

C14

C15

C16

C17

C18

C19

C20

C21

C22

C23

C24

C25

C26

C27

O5

0.20080(8)

0.4376(1)

0.208(1)

0.74240(8)

0.89782(7)

0.9057(9)

1.0039(8)

0.7807(8)

0.7147(7)

0.8928(7)

0.1562(7)

0.852(1)

0.909(1)

0.821(1)

0.7789(9)

0.903(1)

0.8769(9)

0.8359(6)

0.8266(8)

0.8554(9)

0.8028(7)

0.6958(7)

0.5589(7)

0.5083(7)

0.3765(8)

0.2917(8)

0.3430(8)

0.4741(8)

0.643(1)

0.601(1)

0.516(1)

0.504(1)

0.579(2)

1.097(1)

1.112(1)

1.1218(9)

1.1156(9)

1.100(1)

0.601(3)

0.556(3)

0.581(4)

0.695(4)

0.721(4)

0.86493(4)

0.81978(4)

1.0156(4)

0.8138(4)

0.7037(5)

0.9455(4)

0.5134(4)

0.6631(4)

0.9555(6)

0.8338(5)

0.7440(6)

0.8980(6)

0.5324(5)

0.6079(5)

0.6683(4)

0.6489(5)

0.5725(6)

0.7486(4)

0.7797(4)

0.7491(4)

0.6739(5)

0.6455(5)

0.6902(5)

0.7651(5)

0.7935(5)

0.9392(9)

0.8607(9)

0.8368(8)

0.902(1)

4.32(4)

4.39(4)

11.6(6)

9.1(4)

8.2(5)

8.7(5)

5.1(4)

8.1(5)

7.3(6)

5.9(5)

5.4(5)

5.5(5)

5.8(6)

5.1(5)

2.8(3)

4.2(4)

5.3(5)

3.0(3)

2.9(3)

3.1(3)

4.3(4)

4.8(4)

4.7(4)

5.8(5)

4.8(4)

8.8(8)

8.1(8)

8.3(8)

9.3(9)

10(1)

−0.0485(8)

0.7583(8)

0.617(1)

0.205(1)

0.815(1)

0.217(1)

0.044(1)

0.641(1)

0.554(1)

0.334(1)

0.375(1)

0.2766(8)

0.1379(9)

0.109(1)

0.3136(8)

0.4195(8)

0.5310(8)

0.529(1)

0.625(1)

0.726(1)

0.731(1)

0.634(1)

0.020(2)

0.037(2)

0.190(2)

0.264(2)

0.161(2)

0.509(2)

0.449(2)

0.290(2)

0.246(2)

0.388(2)

0.922(3)

0.806(5)

0.743(4)

0.770(4)

0.848(4)

−0.0220(7)

−0.0807(7)

−0.1639(6)

−0.1583(6)

−0.0709(7)

isolated in a 37% yield after removal of the solvent. MS

(FAB): m/e 713 (M⁺). Anal. Found: C, 56.79; H, 2.99;

N, 3.75. C₃₄H₂₂N₂O₄Mo₂Calc.: C, 57.16; H, 3.10; N,

3.92%. Further elution with THF/CH₂Cl₂(3:2) gave a

purple band from which the powder 5 was isolated in an

11% yield, again after removal of the solvent. MS (FAB):

m/e 1147 (M⁺). Anal. Found: C, 50.14; H, 3.27; N, 2.40.

C₄₈H₃₂N₂O₈Mo₂. Calc.: C, 50.20; H, 3.01; N, 2.44%.

2.5. (v₄-p^2:2:2:2-BPEB)[Co₂(CO)₆]₂(6)

0.9658(8)

0.833(1)

0.7582(9)

0.7816(8)

0.8663(8)

0.896(1)

0.362(2)

0.383(2)

0.464(2)

0.486(2)

10(1)

A solution of Co₂(CO)₈(241 mg, 0.71 mmol) in hexane

(50 ml) was added slowly to a solution of BPEB (200 mg,

0.35 mmol) in 100 ml of CH₂Cl₂. The resulting solution

was stirred at room temperature (r.t.) for 24 h and the

solvent was removed in vacuo. The residue was chro-

matographed using THF/CH₂Cl₂(1:15) as eluant. The

brown band collected was pumped to dryness and the

residue recrystallized from CH₂Cl₂/hexane to give com-

plex 6 as brown powder in a 43% yield (262 mg). MS

8.8(9)

8.0(8)

8.4(8)

11(1)

19.0(9)

24(1)

23(1)

24(1)

23(1)

C28

C29

C30

C31

0.422(3)

260

J.T. Lin et al. / Journal of Organometallic Chemistry 564 (1998) 257–266

Table 4

CH₂Cl₂/hexane (1:3) in a 36% yield. MS (FAB): m/e

Atomic coordinates for complexes 9

877 (M⁺). Anal. Found: C, 54.38; H, 3.54.

C₄₀H₃₀O₄Fe₂Mo₂. Calc.: C, 54.71; H, 3.44%.

Atom

x

y

z

B_iso

2.9. (v₄-p^2:2:2:2-DFEHD)[Cp₂Mo₂(CO)₄][Co₂(CO)₆] (10)

Mo1

Mo2

Fe1

Fe2

O1

O2

O3

O4

C1

C2

C3

C4

C5

C6

C7

C8

C9

C10

C11

C12

C13

C14

C15

C16

C17

C18

C19

C20

C21

C22

C23

C24

C25

C26

C27

C28

C29

C30

C31

C32

C33

C34

C35

C36

C37

C38

C39

C40

0.83715(3)

0.80401(3)

0.64795(4)

0.65277(5)

0.6675(3)

0.8042(3)

0.9545(3)

0.9691(3)

0.7287(4)

0.8110(3)

0.8994(4)

0.9072(4)

0.7644(3)

0.7075(3)

0.6037(3)

0.5476(3)

0.5731(3)

0.5804(3)

0.9513(3)

0.9111(4)

0.9370(4)

0.9916(4)

1.0022(3)

0.7308(6)

0.6653(4)

0.6949(5)

0.7810(5)

0.8085(5)

0.7496(3)

0.16882(3)

0.6961(3)

0.7619(3)

0.7936(3)

0.5632(4)

0.5076(3)

0.5189(3)

0.5834(4)

0.6105(4)

0.5814(4)

0.6459(4)

0.6182(4)

0.5387(4)

0.5162(3)

0.7602(7)

0.7891(5)

0.7340(8)

0.6645(6)

0.6843(8)

0.87747(4)

0.59125(4)

0.54175(7)

0.98612(8)

1.0730(4)

1.0128(5)

0.4629(5)

0.7392(4)

0.9977(5)

0.9581(6)

0.5117(6)

0.6953(6)

0.6870(5)

0.7398(4)

0.7554(5)

0.8174(5)

0.8899(5)

0.9563(5)

0.8335(6)

0.9664(6)

1.0516(6)

0.9680(7)

0.8352(6)

0.3754(7)

0.4767(7)

0.5568(7)

0.5099(8)

0.3958(8)

0.6624(5)

0.7475(4)

0.7002(5)

0.5862(5)

0.5634(5)

0.4401(6)

0.5274(6)

0.4833(5)

0.3683(5)

0.3408(5)

1.0358(5)

1.1452(5)

1.1944(6)

1.1138(7)

1.0168(6)

0.84691)

0.9450(9)

0.9448(8)

0.839(1)

0.07382(2)

0.02603(2)

0.18043(3)

−0.19532(3)

0.0866(2)

−0.0417(2)

0.1198(2)

−0.0158(2)

0.0820(2)

−0.0008(2)

0.0857(2)

0.0044(2)

0.0974(2)

0.0522(2)

2.57(2)

2.90(2)

2.60(3)

3.54(3)

5.7(2)

7.0(2)

5.3(2)

3.6(2)

4.4(3)

3.9(3)

2.6(2)

2.4(2)

2.8(2)

3.1(2)

3.3(2)

3.6(2)

3.9(2)

4.0(3)

4.9(3)

4.1(3)

6.3(4)

5.2(3)

5.0(3)

6.2(4)

7.3(4)

2.6(2)

2.7(2)

3.4(2)

3.5(2)

3.1(2)

4.0(2)

3.9(2)

3.7(2)

4.0(3)

3.7(2)

4.2(3)

4.9(3)

5.1(3)

4.3(3)

7.6(5)

7.4(5)

7.1(5)

8.4(5)

8.1(6)

Complex 10 was synthesized by the same procedure

used in the synthesis of 7 except that complex 9 was

used instead of complex 4. Dark green complex 7 was

eluted with CH₂Cl₂/hexane (1:9) in a 40% yield. MS

(FAB): m/e 1163 (M⁺). Anal. Found: C, 47.02; H,

2.50. C₄₆H₃₀O₁₀Co₂Fe₂Mo₂. Calc.: C, 47.46; H, 2.60%.

2.10. (v₄-p^1:1:2:2-DPB)[W(CO)₅]₂[Cp₂Mo₂(CO)₄] (11)

A THF solution (180 ml) of W(CO)₅(THF) prepared

in situ from W(CO)₆(551 mg, 0.78 mmol) was trans-

0.0388(2)

Table 5

−0.0028(2)

−0.0471(2)

−0.0862(2)

0.1535(2)

0.1565(2)

0.1160(2)

Atomic coordinates for complexes 13

Atom

x

y

z

B_iso

W

0.38888(5)

0.67931(9)

0.92452(9)

0.5163(9)

0.4320(9)

0.800(1)

1.163(1)

1.1614(9)

0.436(1)

0.696(1)

0.348(1)

0.055(1)

0.209(1)

0.525(1)

0.764(1)

1.074(1)

1.076(1)

0.418(1)

0.587(1)

0.366(2)

0.177(1)

0.277(1)

0.445(1)

0.512(1)

0.6680(9)

0.743(1)

0.664(1)

0.745(1)

0.854(1)

0.9302(9)

0.886(1)

1.046(1)

0.491(2)

0.623(3)

0.728(2)

0.643(4)

0.506(2)

0.793(1)

0.950(2)

1.037(1)

0.938(2)

0.784(1)

0.20707(1)

0.04220(3)

0.11261(3)

0.1649(3)

0.1184(3)

0.0605(3)

0.0440(3)

0.1169(3)

0.2901(3)

0.2323(3)

0.1267(3)

0.1876(4)

0.2697(3)

0.0907(4)

0.0575(4)

0.0686(4)

0.1153(4)

0.2598(4)

0.2236(4)

0.1552(4)

0.1929(4)

0.2463(4)

0.1349(4)

0.1104(3)

0.1162(3)

0.1477(4)

0.1703(4)

0.0910(3)

0.0575(3)

0.0289(3)

0.0295(3)

0.2285393)

0.77553(7)

0.77580(7)

0.3663(6)

0.7899(7)

1.0274(6)

0.8915(7)

0.5870(8)

0.3947(6)

0.1094(7)

0.0524(7)

0.3119(9)

0.0516(7)

0.7876(9)

0.9300(9)

0.8480(9)

0.6562(9)

0.3358(9)

0.1550(8)

0.1181(9)

0.2848(9)

0.1162(8)

0.4260(9)

0.5162(8)

0.5515(7)

0.489(1)

3.62(2)

3.24(4)

3.57(4)

3.4(3)

6.4(4)

7.3(5)

7.1(4)

7.5(5)

6.4(4)

8.0(5)

9.1(6)

9.5(6)

8.6(5)

4.4(5)

4.9(5)

4.8(6)

4.7(5)

4.0(5)

4.7(5)

5.3(6)

5.6(6)

5.1(6)

4.6(5)

4.0(4)

3.0(4)

6.0(6)

6.2(6)

3.2(5)

3.1(4)

3.2(4)

4.2(5)

4.5(5)

7.3(9)

8.3(9)

11(2)

Mo1

Mo2

N

O1

O2

O3

O4

O5

O6

O7

O8

O9

C1

C2

C3

C4

C5

0.0866(2)

0.1108(2)

−0.0002(3)

−0.0194(2)

−0.0571(2)

−0.0647(3)

−0.0275(3)

0.1526(2)

0.1790(2)

0.2328(2)

0.2408(2)

0.1922(2)

0.1169(2)

0.1436(2)

0.19752(2)

0.2048(2)

0.1552(2)

−0.1353(2)

−0.1424(2)

−0.1960(2)

−0.2222(2)

−0.1849(2)

−0.1709(3)

−0.2014(5)

−0.2506(4)

−0.2515(4)

−0.2003(5)

C6

C7

C8

C9

C10

C11

C12

C13

C14

C15

C16

C17

C18

C19

C21

C22

C23

C24

C25

C26

C27

C28

C29

C30

0.399(1)

0.6468(7)

0.6578(7)

0.5778(7)

0.4612(8)

0.6143(8)

0.806(2)

0.855(1)

0.773(3)

0.672(2)

0.694(2)

0.903(1)

0.945(1)

0.859(1)

0.76991)

0.796(1)

0.7810(7)

−0.0019(4)

−0.0121(4)

−0.0277(5)

−0.0356(5)

−0.0234(8)

−0.0103(5)

0.1592(4)

0.1563(4)

0.1756(5)

0.1910(4)

0.1806(4)

during the synthesis of ferrocenylbutadiyne following

the known procedure [12]. MS (FAB): m/e 444 (M⁺).

Anal. Found: C, 70.32; H, 4.31. C₂₆H₂₀Fe₂. Calc.: C,

70.31; H, 4.54%.

13(2)

8.7(10)

5.2(6)

6.1(6)

7.2(8)

6.7(7)

5.6(6)

2.8. (v₂-p^2:2-DFEHD)[Cp₂Mo₂(CO)₄] (9)

Complex 9 was synthesized by the same procedure

used in the synthesis of 1 except that DFEHD was used

instead of DPB. Dark purple complex 7 was eluted with

J.T. Lin et al. / Journal of Organometallic Chemistry 564 (1998) 257–266

Table 6 (Continued)

261

Table 6

˚

Selected bond distances (A) and angles (°) for complexes 1, 2·THF,

9, and 13

1

2·THF

9

13

1

2·THF

9

13

Mo2–C5–C6

Mo2–C6–C5

70.8(2)

72.8(3)

˚

Bond length (A)

Mo1–C10–C11 70.4(3)

Mo1–C11–C10 73.0(3)

Mo2–C10–C11 73.6(3)

Mo2–C11–C10 69.3(3)

Mo1–C15–C16

Mo1–C16–C15

Mo2–C15–C16

Mo2–C16–C15

C21–C5–C6

C5–C6–C7

C6–C7–C8

C7–C8–C9

C8–C9–C10

70.4(4)

73.0(4)

72.3(4)

71.5(4)

Mo1–Mo2

Mo1–C1

Mo1–C2

Mo1–C4

Mo2–C1

Mo2–C2

Mo2–C3

Mo2–C4

Mo1–C5

Mo1–C6

Mo2–C5

Mo2–C6

Mo1–C10

Mo1–C11

Mo2–C10

Mo2–C11

W–C5

2.9735(8)

1.986(6)

1.998(6)

2.894(5)

2.965(2)

1.96(1)

1.958(9)

2.9727(6)

1.964(5)

1.994(6)

2.781(5)

2.971(1)

1.97(1)

1.96(1)

70.3(5)

73.1(5)

72.7(5)

70.9(5)

2.86(1)

1.98(1)

1.956(6)

1.960(6)

1.99(1)

1.97(1)

1.967(6)

1.936(6)

2.223(4)

2.240(4)

2.186(4)

2.161(4)

133.0(4)

129.9(4)

130.8(4)

129.1(4)

170.2(5)

175.5(5)

2.209(4)

2.176(4)

2.140(4)

2.194(4)

2.187(7)

2.154(7)

2.189(7)

2.198(7)

C9–C10–C31

C7–C10–C11

133.7(4)

134.5(6)

135.4(6)

C10–C11–C12 138.8(4)

C11–C12–C13 175.2(5)

C12–C13–C14 177.5(5)

C12–C15–C16

2.01(1)

2.02(1)

2.01(1)

2.02(1)

1.96(1)

W–C6

W–C7

W–C8

W–C9

135.6(8)

134.6(8)

C15–C16–C17

C5–C6

C7–C8

C9–C10

C10–C11

C1–O1

C2–O2

C3–O3

C4–O4

1.357(6)

1.325(6)

1.192(8)

ferred to a ﬂask containing complex 1 (500 mg, 0.78

mmol). The solution was stirred at r.t. for 24 h, and the

solvent removed under vacuum. The residue was chro-

matographed using CH₂Cl₂/hexane (1:3) as eluent. The

deep red band collected was pumped dry and the

residue recrystallized from CH₂Cl₂/hexane to give com-

plex 11 as a deep red powder in a 26% yield (265 mg).

MS (FAB): m/e 1283 (M⁺). Anal. Found: C, 35.57; H,

1.35; N, 2.12. C₃₈H₁₈N₂O₁₄Mo₂W₂. Calc.: C, 35.52; H,

1.41; N, 2.06%.

1.379(6)

1.14(8)

1.136(7)

1.155(7)

1.162(7)

1.363(9)

1.14(1)

1.12(1)

1.13(1)

1.151(7)

1.140(7)

1.141(7)

1.178(7)

1.15(1)

1.16(1)

1.15(1)

1.14(1)

1.15(2)

1.13(2)

1.16(1)

C5–O5

C6–O6

C7–O7

C8–O8

C9–O9

C12–C13

Mo1–C15

Mo1–C16

Mo2–C15

Mo2–C16

1.201(7)

2.11. (v₄-p^1:1:2:2-BPEB)[W(CO)₅]₂[Cp₂Mo₂(CO)₄] (12)

2.195(9)

2.159(8)

2.180(9)

2.202(9)

Complex 12 was synthesized by the same procedure

employed in the synthesis of 11 except that complex 4

was used instead of complex 1. Orange–red complex 12

was eluted with CH₂Cl₂/hexane (1:2) in a 46% yield.

Anal. Found: C, 38.55; H, 1.80, N, 2.04.

C₄₄H₂₂N₂O₁₄Mo₂W₂. Calc.: C, 38.82; H, 1.63; N,

2.06%.

Bond angle (°)

Mo1–C1–O1

Mo1–C2–O2

Mo2–C3–O3

Mo2–C4–O4

C1–Mo1–C2

C3–Mo2–C4

C5–W–C6

C5–W–C7

C5–W–C8

C5–W–C9

C6–W–C7

C6–W–C8

C6–W–C9

C7–W–C8

C7–W–C9

C8–W–C9

Mo1–C5–C6

Mo1–C6–C5

179.6(5)

176.6(5)

176.0(4)

169.6(5)

84.7(2)

91(2)

168(1)

177.1(4)

172.9(4)

178.6(5)

167.6(4)

82.6(2)

176.8(9)

168.5(9)

178.1(9)

179.5(8)

88.4(5)

83.7(4)

90.2(4)

177.8(4)

92.0(4)

89.4(4)

87.6(4)

173.3(4)

87.4(4)

90.1(5)

90.2(4)

86.3(5)

177.5(9)

176.5(8)

177.2(7)

88.9(4)

83.1(4)

87.8(2)

2.12. (v₆-p^1:1:2:2:2:2-BPEB)[W(CO)₅]₂[Cp₂Mo₂(CO)₄]₂

(13)

Complex 13 was synthesized by the same procedure

employed in the synthesis of 11 except that complex 5

was used instead of complex 1. Orange–red complex 13

was eluted with CH₂Cl₂/hexane (1:2) in a 44% yield.

Anal. Found: C, 38.66; H, 1.70, N, 1.32.

C₅₈H₃₂N₂O₁₈Mo₄W₂. Calc.: C, 38.80; H, 1.80; N,

1.56%.

73.0(3)

71.6(3)

262

J.T. Lin et al. / Journal of Organometallic Chemistry 564 (1998) 257–266

Scheme 1.

2.13. (v₆-p^1:1:2:2:2:2-BPEB)[W(CO)₅]₂[Co₂(CO)₆]₂(14)

grams. Intensities were collected and corrected for

decay, absorption (empirical, C-scan) and L_Peffects.

The structures were solved by a combination of direct

methods [14] and difference Fourier methods and fur-

ther reﬁned by full-matrix least-squares techniques. All

non-H atoms were reﬁned anisotropically, while the H

atoms were included in the structure factor calculation

Complex 13 was synthesized by the same procedure

employed in the synthesis of 11 except that complex 6

was used instead of complex 1. Orange–red complex 14

was eluted with CH₂Cl₂/hexane (1:2) in a 46% yield.

Anal. Found: C, 33.42; H, 0.78, N, 1.75.

C₄₂H₁₂N₂O₂₂Co₂W₂. Calc.: C, 33.65; H, 0.81; N, 1.87%.

˚

in idealized positions with d_C–H=0.95 A. The ﬁnal

positional parameters are listed in Tables 2–5, and the

selected interatomic distances and bond angles are

given in Table 6. The THF molecule in 2·THF is

disordered. An inversion center is present in the cen-

troid of the benzene ring in 13.

2.14. (v₆-p^1:1:2:2:2:2-BPEB)[W(CO)₅]₂[Cp₂Mo₂(CO)₄]

[Co₂(CO)₆] (15)

Complex 15 was synthesized by the same procedure

used in the synthesis of 11 except that complex 7 was

used instead of complex 1. Orange–red complex 13 was

eluted with CH₂Cl₂/hexane (1:2) in a 35% yield. Anal.

Found: C, 36.31; H, 1.29, N, 1.34. C₅₀H₂₂N₂O₂₀-

Co₂Mo₂W₂. Calc.: C, 36.46; H, 1.35; N, 1.40%.

3. Results and discussion

Being isolobal [15] to an organic alkyne,

Cp₂Mo₂(CO)₄and ‘Co₂(CO)₆’ have a great tendency to

bind an alkyne in a ﬂyover fashion. As expected, one of

the alkyne moieties in DPB, BPEB, APPA, FPA, and

DFEHD are readily ligated to Cp₂Mo₂(CO)₄and

‘Co₂(CO)₆’, derived from Co₂(CO)₈. Although the com-

plex (v₄-p^2:2:2:2-BPEB)[Cp₂Mo₂(CO)₄]₂can be easily ob-

tained from the reaction of BPEB with Cp₂Mo₂(CO)₄,

(v₄-p^2:2:2:2-DPB)[Cp₂Mo₂(CO)₄]₂is elusive from the re-

action of DPB, even when an excess of Cp₂Mo₂(CO)₄is

used. It is interesting to note that the two consecutive

alkynes in Me₃SiCꢀC–CꢀCSiMe₃are both capable of

2.15. Crystallographic studies

Crystals of 1 and 9 were grown by slowly diffusing

hexane into a concentrated solution of relevant com-

plexes in CH₂Cl₂. Crystals of 2·THF were grown by

slowly diffusing hexane into a concentrated solution of

relevant complex in THF. Crystals of 13 were grown by

slowly diffusing hexane into a concentrated solution of

complex 13 in ethylacetate. These crystals were then

mounted on a thin-walled glass capillaries. Diffraction

data were measured using an Enraf-Nonious CAD4

diffractometer employing an ꢀ−2q scan mode. The

unit cell dimensions were determined by centering 25

reﬂections in an appropriate 2q range. Other relevant

experimental details are listed in Table 1. All data

reduction and reﬁnements were performed on a Mi-

croVax 3800 computer employing NRCVAX [13] pro-

interacting with

a

metal and form (v₄-p^2:2:2:2

-

Me₃SiCꢀC–CꢀCSiMe₃)[Cp₂W₂(CO)₄]₂([4]b). We previ-

ously demonstrated that ligation of pyridine in DPB

and BPEB to ‘W(CO)₅’ resulted in the formation of

(v-PY)[W(CO)₅]₂(PY=DPB, BPEB) ([6]a). Complexa-

tion of the alkyne moiety with Cp₂Mo₂(CO)₄or

‘Co₂(CO)_6’does not extinguish the ligating ability of the

J.T. Lin et al. / Journal of Organometallic Chemistry 564 (1998) 257–266

263

pyridine in DPB and BPEB. Therefore, complexes (v₄-

been synthesized easily, as illustrated in Scheme 1.

p^1:1:2:2-DPB)[W(CO)₅]₂[Cp₂Mo₂(CO)₄] (11), (v₄-p^1:1:2:2

-

The spectroscopic properties (Table 7) of these new

complexes are consistent with their formulation. For

complexes (1–5 and 9) which contain only Cp₂Mo₂(CO)₄

metal moiety, three characteristic carbonyl stretching

bands at ca. 1990 s, 1930 vs, and 1840 cm⁻¹are observed,

BPEB)[W(CO)₅]₂[Cp₂Mo₂(CO)₄] (12), (v₆-p^1:1:2:2:2:2-BP-

EB)[W(CO)₅]₂[Cp₂Mo₂(CO)₄]₂(13), (v₆-p^1:1:2:2:2:2-BP-

EB)[W(CO)₅]₂[Co₂(CO)₆]₂(14), and (v₆-p^1:1:2:2:2:2

-

BPEB)[W(CO)₅]₂[Cp₂Mo₂(CO)₄][Co₂(CO)₆] (15) have

Table 7

IR spectra in the w(CO) region and ¹H-NMR spectra of compounds 1–15

Compound

w(CꢀC),^aw(CO) (cm⁻¹

)

l (ppm)^b,cJ (Hz)

1

2001 s, 1939 vs, 1849 m

1984 s, 1924 vs, 1841 m

1987 s, 1925 vs, 1843 m

2200 w, 1989 s, 1927 vs, 1845 m

NCH (8.49, d, 2 H, ³J(H–H)=9.1); NCH (8.46, d, 2 H,

³J(H–H)=9.1); NCHCH (7.34, d, 2 H); NCHCH (7.32, d,

2 H), C₅H₅(5.47, s, 10 H)

2

3

4

NCH (8.36, d, 2 H, ³J(H–H)=5.8); NCHCH (7.05, d, 2 H);

H₂NCCH (6.79, d, 2 H, ³J(H–H)=8.5); H₂NCCH (6.51, d,

2 H); C₅H₅(5.35; s, 10 H); NH₂(3.65, s, 2 H)

NCH (8.56, d, 2 H, ³J(H–H)=5.9); NCHCH (7.71, d, 2 H);

C₅H₅(5.33; s, 10 H); C₅H₄(4.28, t, 2 H, J(H–H)=1.8);

C₅H₄(4.20, t, 2 H, J(H–H)=1.8); C₅H₅(4.07; s, 5 H)

NCH (8.60, d, 2 H, ³J(H–H)=6.0); NCH (8.38, d, 2 H,

³J(H–H)=6.0); C₆H₄(7.45, d, 2 H, ³J(H–H)=8.0);

NCHCH (7.42, d, 2 H, ³J(H–H)=6.0); C₆H₄(7.09, d, 2 H);

NCHCH (7.01, d, 2 H, ³J(H–H)=6.0); C₅H₅(5.37; s, 10 H)

NCH (8.33, d, 4 H, ³J(H–H)=6.0); NCHCH (6.98, d, 4 H);

C₆H₄(6.87, s, 4 H); C₅H₅(5.34; s, 20 H)

5

6

7

1979 s, 1915 vs, 1836 m

2092 m, 2061 vs, 2033 s

NCH (8.58, d, 4 H, ³J(H–H)=4.8); C₆H₄(7.55, s, 4 H);

NCHCH (7.45, d, 4 H)

2092 m, 2058 vs, 2029 s, 1998 m, 1937 s, 1850 m

NCH (8.59, d, 2 H, ³J(H–H)=6.1); NCH (8.34, d, 2 H,

³J(H–H)=6.1); C₆H₄(7.51, m, 4 H); NCHCH (7.10, d, 2

H, ³J(H–H)=6.1); NCHCH (7.00, d, 2 H); C₅H₅(5.38; s,

10 H)

8^d

9^d

ꢁCH (6.00, s, 2 H); C₅H₄(4.47; t, 4 H, J(H–H)=1.8); C₅H₄

(4.30; t, 4 H, J(H–H)=1.8); C₅H₅(4.23, s, 10 H);

ꢁCH (7.69, d, 1 H, ³J(H–H)=11.1); ꢁCH (6.14, d, 1 H);

C₅H₅(5.38; s, 10 H); C₅H₄(4.44, t, 2 H, J(H–H)=1.8);

C₅H₄(4.29; t, 2 H, J(H–H)=1.8); C₅H₄and C₅H₅(4.24, m,

9 H); C₅H₅(4.14, s, 5 H)

2160 w, 1982 s, 1918 vs, 1832 s

10^d

2083 m, 2047 vs, 2019 s, 1984 w, 1927 s, 1835 m

ꢁCH (7.93, d, 1 H, ³J(H–H)=14.5); ꢁCH (7.41, d, 1 H);

C₅H₅(5.41; s, 10 H); C₅H₄(4.54, t, 2 H, J(H–H)=1.8);

C₅H₄(4.49; t, 2 H, J(H–H)=1.8); C₅H₄(4.38, t, 2 H; J(H–

H)=1.8); C₅H₅(4.32, s, 5 H); C₅H₄(4.27, t, 2 H; J(H–

H)=1.8); C₅H₅(4.20, s, 5 H)

11

12

2168 w, 2069 m, 2009 w, 1955 sh, 1931 vs, 1903 s, 1863 w

2200 w, 2069 m, 1996 m, 1933 vs, 1901 s, 1859 w

NCH (8.90, d, 2 H, ³J(H–H)=6.6); NCH (8.74, d, 2 H,

³J(H–H)=6.6); NCHCH (7.43, pseudo triplet, 4 H, ³J(H–

H)=6.6); C₅H₅(5.56; s, 10 H)

NCH (9.01, d, 2 H, ³J(H–H)=6.7); NCH (8.68, d, 2 H,

³J(H–H)=6.7); NCHCH (7.53, d, 2 H, ³J(H–H)=6.7);

C₆H₄(7.51, d, 2 H, ³J(H–H)=8.6); NCHCH (7.12, d, 2 H,

³J(H–H)=6.7); C₆H₄(7.10, d, 2 H); C₅H₅(5.42; s, 10 H)

NCH (8.63, d, 4 H, ³J(H–H)=7.5); NCHCH (7.11, d, 4 H);

C₆H₄(6.90, s, 4 H); C₅H₅(5.37; s, 20 H)

13

14

15

2069 w, 1995 m, 1932 vs, 1900 m, 1853 m

2094 m, 2062 s, 2035 s, 1976 w, 1930 vs, 1903 m

NCH (8.99, d, 4 H, ³J(H–H)=6.4); C₆H₄(7.73, s, 4 H);

NCHCH (7.65, d, 4 H)

2094 m, 2068 s, 2060 s, 2033 m, 1998 w, 1975 w, 1928 vs,

1901 w, 1856 m

NCH (8.97, d, 2 H, ³J(H–H)=6.8); NCH (8.67, d, 2 H,

³J(H–H)=6.8); NCHCH (7.61, d, 2 H, ³J(H–H)=6.8);

C₆H₄(7.53, d, 2 H, ³J(H–H)=8.5); NCHCH (7.13, d, 2 H,

³J(H–H)=6.8); C₆H₄(7.10, d, 2 H); C₅H₅(5.42; s, 10 H)

s, singlet; d, doublet; m, multiplet.

^aMeasured in THF solution except for 6 (in toluene), 7 (in CH₂Cl₂) and 10 (in CH₂Cl₂). ^bMeasured in acetone-d₆except for 6, which was

c

measured in CDCl₃. Reported in ppm relative to TMS (0 ppm). ^dThe signals due to the AA%MM% spin system in symmetrical Cp ligands are, due

to their simple appearance, reported as triplets with coupling constants equal to half of the separation between the two outer lines.

264

J.T. Lin et al. / Journal of Organometallic Chemistry 564 (1998) 257–266

similar to the alkyne complexes of Cp₂Mo₂(CO)₄. The

lower energy stretching bands can be assigned to w(CO)

of the semibridging carbonyl ligand (vide infra) [16].

The carbonyl stretches for Co₂(CO)₆complexed with an

alkyne normally appear above 2000 cm⁻¹[17]. Conse-

quently, we are able to distinguish the carbonyl

stretches due to Co₂(CO)₆from those due to

Cp₂Mo₂(CO)₄in complexes 7 and 10. For complexes

11–13, the three moderate/strong carbonyl stretches

from W(CO)₅moiety are partially overlapping with the

three carbonyl stretches from Cp₂Mo₂(CO)₄metal moi-

ety. However, the two sets of carbonyl stretches are

discernible by comparison of the spectra of 11–13 with

those of 1 and 4, and the presence of the semibridging

carbonyl ligand in 11–13 is evident. In 14 and 15, the

carbonyl stretches for Co₂(CO)₆appear at the highest

frequency and can be distinguished from others. The

presence of the semibridging carbonyl ligand in 15 is

also evident. A weak w(CꢀC) stretching band is ob-

served at ca. 2200 cm⁻¹in all complexes which contain

unligated alkyne moiety.

An interesting feature in the ¹H-NMR spectra of

these complexes is that ligation of the alkyne moiety

has a great inﬂuence on the chemical shift of DPB,

BPEB, and DFEHD. Complexation of DPB and BPEB

with Cp₂Mo₂(CO)₄results in an upﬁeld shift of the

nearby pyridyl and phenyl protons by 0.2–0.4 ppm

(DPB: H_h(py)=8.66, H_i(py)=7.53 ppm; 1: H_h(py)=

8.49, 8.46, H_i(py)=7.33, 7.32 ppm; BPEB: H_h(py)=

8.63, H_i(py)=7.47, Ph=7.66 ppm; 4, H_h(py)=8.38,

H_i(py)=7.01, (Ph)_a=7.45 ppm, (Ph)_b=7.09 ppm). In

contrast, the pyridyl protons nearby the uncomplexed

alkyne have negligible change in chemical shift (4:

H_h% (py)=8.60, H’_b(py)=7.42 ppm). Complexation of

both alkyne entities with Cp₂Mo₂(CO)₄leads to a larger

upﬁeld shift of pyridyl and phenyl protons than 4 (5:

H_h(py)=8.31, H_i(py)=6.97, Ph=6.88 ppm). In 9, the

oleﬁn entity of DFEHD has a cis geometry on the basis

Fig. 1. ORTEP drawing of (v₂-p^2:2-DPB)[Cp₂Mo₂(CO)₄] (1). Thermal

ellipsoids are drawing in 50% probability boundaries.

3

of the coupling constant, J(H–H), and the structural

determination (vide infra). The effect of complexation

of the alkyne entity in DFEHD with Cp₂Mo₂(CO)₄or

Co₂(CO)₆on the chemical shift of oleﬁnic protons

(DFEHD: l=6.00; 9: l=7.69, 6.14; 10: l=7.93, 7.41

ppm) is greater than that in DPB and BPEB, albeit in

the opposite direction. The spectra of 2 and 3 seem to

follow the same trend. However, at this juncture in

time, we do not have a rationale for these differences

on the basis of the known substituent effects [18].

Pyridyl protons shift to lower ﬁeld upon ligation to

W(CO)₅, as expected.

The molecular structures of (v₂-p^2:2-DPB)[Cp₂Mo₂

(CO)₄] (1), (v₂-p^2:2-APPA)[Cp₂Mo₂(CO)₄] (2), (v₂-p^2:2

-

DFEHD)[Cp₂Mo₂(CO)₄]

(9),

and

(v₆-p^1:1:2:2:2:2

BPEB)[W(CO)₅]₂[Cp₂Mo₂(CO)₄]₂(13) were established

by X-ray diffraction analysis. The ORTEP drawings of

1, 2, 9, and 13 are shown in Figs. 1–4, respectively. A

Fig. 2. ORTEP drawing of (v₂-p^2:2-APPA)[Cp₂Mo₂(CO)₄] (2). Ther-

mal ellipsoids are drawing in 50% probability boundaries.

J.T. Lin et al. / Journal of Organometallic Chemistry 564 (1998) 257–266

265

prominent feature of these structures is a signiﬁcant

elongation of the CꢀC bond occurs upon coordination

of the alkyne. This is accompanied by the deviation of

the C–CꢀC bond angle from the ideal angle of 180°

(Table 8). The other prominent feature in these com-

plexes is that one of the CO ligands (1: C₄O₄; 2: C₁O₁;

9: C₄O₄; 13: C₂O₂) in Cp₂Mo₂(CO)₄is coordinated in a

semibridged fashion [19]. This can be easily recognized

by the characteristic bond angle M–C–O (1: semibridg-

ing, 169.6(5), others 178(2)°; 2: semibridging, 168(1),

Fig. 3. ORTEP drawing of (v₂-p^2:2-DFEHD)[Cp₂Mo₂(CO)₄] (9). Thermal ellipsoids are drawing in 50% probability boundaries.

Fig. 4. ORTEP drawing of (v₆-p^1:1:2:2:2:2-BPEB)[W(CO)₅]₂[Cp₂Mo₂(CO)₄] (13). Thermal ellipsoids are drawing in 50% probability boundaries.

Table 8

Bond distances (CꢀC) and angles (C–CꢀC) for alkynes in 1, 2, 9 and 13

˚

Compound

Distances (ligated) (A)

Distances (unligated) (A)

Angles (ligated) (°)

Angles (unligated) (°)

175.2(5), 177.5(5)

175.5(5), 170.2(5)

1

2

9

13

1.379(6)

1.37(1)

1.357(6)

1.37(1)

1.201(7)

1.192(8)

133.7(4), 138.8(4)

134.4(6), 135.4(7)

133.0(4), 129.9(4)

134.6(8), 135.6(8)

266

J.T. Lin et al. / Journal of Organometallic Chemistry 564 (1998) 257–266

Chem. Rev. 96 (1996) 759. (b) P. Lange, A. Schier, H. Schmid-

bauer, Inorg. Chem. 35 (1966) 637. (c) A. Miedaner, C.J. Curtis,

R.M. Barkley, D.L. Dubois, Inorg. Chem. 33 (1994) 5482. (d)

K.D. Karlin (Ed.), Progress in Inorganic Chemistry, vol. 42,

Wiley, New York, 1994, pp. 239. (e) A.L. Balch, Pure Appl.

Chem. 60 (1988) 555.

others 177(1)°; 9: semibridging, 167.6(4), others 176(3)°;

13: semibridging, 168.5(9), others 178(2)°) where M is

the metal to which it is ligated, and the M%–C distance

˚

(1: 2.894(5); 2: 2.86(1); 9: 2.781(5); 13: 2.86(1) A) where

M% is the metal to which it is semi-bridged. These values

are within the range found in similar complexes ([16]a,

[20]). Other relevant crystal data appear to be normal.

The Mo–Mo distances, which range from 2.964 (2) to

[4] (a) C.J. McAdam, N.W. Duffy, B.H. Robinson, J. Simpson,

Organometallics 15 (1996) 3935. (b) H. Lang, S. Blau, G. Rhein-

wald, L. Zsolnai, J. Organomet. Chem. 494 (1995) 65. (c) D.

Osella, L. Milone, C. Nervi, M. Ravera, J. Organomet. Chem.

488 (1995) 1. (d) K. Onitsuka, X.-Q Tao, W.-Q. Wang, Y.

Otsuka, K. Sonogashira, T. Adachi, T. Yoshida, J. Organomet.

Chem. 473 (1994) 195. (e) C.E. Housecroft, B.F.G. Johnson,

M.S. Khan, J. Lewis, P.R. Raithby, M.E. Robson, D.A. Wilkin-

son, J. Chem. Soc. Dalton Trans. (1992) 3171. (f) G.H. Worth,

B.H. Robinson, J. Simpson, Organometallics 11 (1992) 501.

[5] (a) E. Sappa, A. Tiripicchio, P. Braunstein, Chem. Rev. 83

(1983) 203. (b) S. Otsuka, A. Nakamura, Adv. Organomet.

Chem. 14 (1975) 245.

[6] (a) J.T. Lin, S.S. Sun, J.J. Wu, L. Lee, K.J. Lin, Y.F. Huang,

Inorg. Chem. 34 (1995) 2323. (b) J.T. Lin, S.S. Sun, J.J. Wu,

Y.C. Liaw, K.J. Lin, J. Organomet. Chem. 517 (1996) 217.

[7] (a) N.J. Long, Angew. Chem. Int. Ed. Engl. 34 (1995) 21. (b)

D.R. Kanis, M.A. Ratner, T.J. Marks, J. Am. Chem. Soc. 114

(1992) 10338.

˚

2.9735(8) A, are comparable to those of analogous

complexes [20]. The tungsten atom in 13 resides in an

approximately octahedral environment, and the two

oleﬁnic protons in 9 are in a mutually cis disposition.

To summarize, we have demonstrated that conju-

gated pyridyl ligands incorporating alkyne entities can

be used to assemble different metal moieties. In com-

plex 13, up to six metal fragments are accommodated.

Our future research aims at designing the ligands with

suitable shape to accommodate metal fragments selec-

tively, and designing an organometallic monomer for

the construction of polymers.

[8] M. Zdeih, K. Wynne, H.R. Allcock (Eds.), Inorganic and

Organometallic Polymers, Adv. Chem. Ser. 224, Am. Chem.

Soc., Washington, DC, 1988.

4. Supplementary material available

[9] J. Buckingham, J. Macintyre (Eds.), Dictionary of Organometal-

lic Compounds, Chapman and Hall, New York, 1984.

[10] L.D. Ciana, A. Haim, J. Heterocycl. Chem. 21 (1984) 607.

[11] D. Curtis, M.S. Hay, Inorg. Synth. 28 (1990) 150.

[12] Z. Yuan, G. Stringer, I.R. Jobe, et al., J. Organomet. Chem. 452

(1993) 115.

Complete crystal data, all bond distances and angles,

positional parameters, anisotropic thermal parameters,

and isotropic thermal parameters, are available, upon

request, from the authors.

[13] E.J. Gabe, Y. LePage, J.P. Charland, F.L. Lee, P.S. White, J.

Appl. Crystallogr. 22 (1989) 384.

[14] P. Main, S.J. Fiske, S.E. Hull, L. Lessinger, G. Germain, J.P.

Declercq, M.M. Woolfson, Multan80: A system of computer

programs for the automatic solution of crystal structures from

X-ray diffraction data, Universities of York, UK and Louvain,

Belgium, 1980.

[15] R. Hoffman, Angew. Chem. Int. Ed. Engl. 21 (1982) 711.

[16] (a) W.I. Bailey, M.H. Chisholm, F.A. Cotton, L.A. Rankel, J.

Am. Chem. Soc. 100 (1978) 5764. (b) R.J. Klingler, W. Butler,

M.D. Curtis, J. Am. Chem. Soc. 97 (1975) 3535.

[17] (a) C.U. Pittman Jr., L.R. Smith, Inorg. Chem. 17 (1978) 1995.

(b) G. Cetini, O. Gambino, R. Rossetti, E. Sappa, J. Organomet.

Chem. 8 (1967) 149.

[18] (a) E. Pretsch, J. Seibl, W. Simon, T. Clerc (Eds.), Tables of

Spectral Data for Structure Determination of Organic Com-

pounds, Springer-Verlag, Berlin, 1983. (b) T.K. Wu, B.P. Dailey,

J. Chem. Phys. 41 (1964) 3307.

Acknowledgements

We thank the Academia Sinica and the National

Science Council for ﬁnal support (Grant NSC-87-2113-

M-001-010).

References

[1] (a) I.M. Lorkovic, R.R. Duff, M.S. Wrighton, J. Am. Chem.

Soc. 117 (1995) 3617. (b) M.E. Broussard, B. Juma, S.G. Train,

W.J. Peng, S.A. Laneman, G.G. Stanley, Science 260 (1993)

1784. (c) P. Kalck, C. Serra, C. Machet, et al., Organometallics

12 (1993) 1021. (d) L. Gelmini, D.W. Stephan, Organometallics

7 (1988) 849.

[2] G. Wilkinson, F.G.A. Stone, E. Abels, (Eds.), Comprehensive

Organometallic Chemistry, vol. 6, Pergamon Press, Oxford, UK,

1982, ch. 40.

[19] (a) E.D. Jemmis, A.R. Pinhas, R. Hoffmann J. Am. Chem. Soc.

102 (1980) 2576. (b) F.A. Cotton, Prog. Inorg. Chem. 21 (1976)

1.

[20] F.A. Cotton, J.D. Jamerson, B.R. Stults, J. Am. Chem. Soc. 98

(1976) 1774.

[3] (a) V. Balzani, A. Juris, M. Venturi, S. Campagna, S. Serroni,

.

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Polynuclear metal complexes linked by conjugated pyridines

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