Reactivity of triosmium clusters with 3,4-dimethyl-1-phenylphosphole and cyanoethyldi-tert-butylphosphine ligands:X-ray crystal structures of [Os3(CO)9(l-OH)(l-H)(g1-PhPC4H2Me2)]and [Os3(CO)11(g1-tBu2PC2H4CN)]

Yomaira Otero • Deisy Pena • Ysaura De Sanctis •

Alejandro Arce • Edgar Ocando-Mavarez •

Ruben Machado • Teresa Gonzalez

Received: 4 October 2013 / Accepted: 13 December 2013 / Published online: 29 December 2013

� Springer Science+Business Media Dordrecht 2013

Abstract Reaction of [Os3(l-H)2(CO)10] with 3,4-dimethyl-

1-phenylphosphole in refluxing cyclohexane affords two

substituted triosmium clusters: [Os3(CO)9(l-H)(l3:g1:g1:g2-

PhPC4H3Me2)] (1) and [Os3(CO)9(H)(l2-g1:g2-PhPC4H4Me2)]

(2), of which cluster 2 exhibits two chromatographically non-

separable isomeric forms attributed to terminal and bridging

coordination of the hydride ligand, respectively. When this

reaction is performed in refluxing THF, the only product is the

cluster [Os3(CO)9(l-OH)(l-H)(g1-PhPC4H2Me2)] (3). Crystal-

lographic information obtained for cluster 3 shows the phosphole

ligand occupying an equatorial position, as expected, while the

OH group is asymmetrically bridging unlike previously reported

similar compounds. Additionally, interaction of the labile cluster

[Os3(CO)11(CH3CN)] with cyanoethyldi-tert-butylphosphine in

dichloromethane at room temperature was found to give

[Os3(CO)11(g1-tBu2PC2H4CN)] (4) as the only product; its

crystallographic characterization shows that the phosphine

ligand coordinates by means of the phosphorus atom in an

equatorial fashion, analogous to compound 3.

Introduction

Studies of the effects of electronic and coordinative defi-

ciency in mononuclear complexes suggest that unsaturated

transition metal clusters should exhibit unique patterns of

chemical behavior with potential applications in catalysis

[1–5]. The geometries adopted by such compounds can

also be an important factor influencing catalytic activity,

since certain geometric features can favor the interaction

with intermediates in the catalytic process [1, 6, 7]. Fur-

thermore, metal clusters may be able to access reaction

modes that have no counterparts in mononuclear chemistry.

This is manifested, for example, in reversible metal–metal

bond cleavage [8–11], skeletal rearrangement without

degradation [12–14] and ligand activation via multisite

coordination [15, 16]. Among the more easily studied low

to medium nuclearity clusters, relatively few unsaturated

species are known, and reactivity studies have been prin-

cipally based on [Os3(l-H)2(CO)10] [6, 17–20], [M(l-

H)L2]x (M = Rh, Ir; X = 2 or 4) [1, 3–5] and

[M4(CO)11(l4-PR)2] (M = Fe, Ru) [21–24]. Evidence for

the uptake of nucleophiles by saturated species has been

obtained for a selected group of clusters, such as the labile

species [M3(CO)12-x(CH3CN)x] (M = Os, Ru; x = 1, 2)

[16, 25–27].

We have been exploring the chemistry of the clusters

[Os3(l-H)2(CO)10] [15] and [Os3(CO)10(CH3CN)2] [16, 26,

27] with phosphole and phosphine ligands, from which we

have found simple substitution complexes, derivatives

containing ring-opened ligands, insertion of a phospholide

unit into a metal–metal bond [15] and bridging phosphido

ligands [27]. In this paper, we describe the reactivity of

unsaturated and saturated triosmium carbonyl clusters with

some versatile phosphorus-containing molecules. Specifi-

cally, we have focused on the reactions between the

unsaturated cluster [Os3(l-H)2(CO)10] and 3,4-dimethyl-1-

phenylphosphole, and those of the labile cluster

[Os3(CO)11(CH3CN)] with cyanoethyldi-tert-butylpho-

sphine; both reactions are easily carried out under mild

conditions.

Y. Otero � D. Pena � Y. De Sanctis � A. Arce (&) �E. Ocando-Mavarez � R. Machado � T. Gonzalez

Centro de Quımica, Instituto Venezolano de Investigaciones

Cientıficas (IVIC), Apartado 21827, Caracas 1020-A, Venezuela

e-mail: ajarce51@gmail.com

123

Transition Met Chem (2014) 39:239–246

DOI 10.1007/s11243-013-9796-3

Experimental

Materials and methods

[Os3(l-H)2(CO)10], [Os3(CO)11(CH3CN)], 3,4-dimethyl-1-

phenylphosphole and cyanoethyldi-tert-butylphosphine

were synthesized as previously described [28–32].

[Os3(CO)12] was used as supplied by Aldrich Chemical

Company, and all solvents were purified by standard

techniques [33].1H, 13C and 31P NMR spectra were recorded using

Bruker Avance AM300 and AM500 spectrometers, and

assignments of carbon chemical shifts were based on

HMBC and HMQC experiments. IR spectra were recorded

on a Perkin–Elmer Spectrum 100 series spectrophotometer.

Crystal structure determinations

Intensity data were recorded at room temperature on a

Rigaku AFC-7S diffractometer equipped with a Mercury

CCD detector using monochromated Mo(Ka) radiation

(k = 0.71070 A). An empirical absorption correction

(multi-scan) was applied using the package CrystalClear.

The structures were solved by direct methods and refined

by full-matrix least-squares on F2 using the SHELXTL-

PLUS package. All non-hydrogen atoms were refined

anisotropically, and hydrogen atoms were added at calcu-

lated positions (C–H = 0.93–0.97A) and refined as riding

with Uiso(H) = 1.2Ueq(C) or 1.5Ueq (methyl C). The

position of the hydride atom was observed in the last

residual density map and was included without any further

refinement. The hydrogen atom on O1 was included in its

found position and refined with isotropic displacement

parameters set at 1.2 9 Ueq.

Reaction of [Os3(l-H)2(CO)10] with 3,4-dimethyl-1-

phenylphosphole in cyclohexane

A solution of [Os3(l-H)2(CO)10] (100 mg, 0.173 mmol)

and 3,4-dimethyl-1-phenylphosphole (25 lL, 0.173 mmol)

in dried cyclohexane (50 mL) was boiled under reflux

under nitrogen for 3.5 h. After evaporation of the solvent,

TLC (SiO2) of the yellow residue (eluant: pentane) gave

two bands identified as [Os3(CO)9(l-H)(l3:g1:g1:g2-

PhPC4H3Me2)] (1) (10 mg, 9 %) and two inseparable iso-

mers of common formula [Os3(CO)9(H)(l2-g1:g2-

PhPC4H4Me2)] (2) (60 mg, 51 %).

Reaction of [Os3(l-H)2(CO)10] with 3,4-dimethyl-1-

phenylphosphole in THF

A solution of [Os3(l-H)2(CO)10] (100 mg, 0.173 mmol)

and 3,4-dimethyl-1-phenylphosphole (25 lL, 0.173 mmol)

in dried tetrahydrofuran (50 mL) was boiled under reflux

under nitrogen for 2 h. After evaporation of the solvent,

TLC (SiO2) of the yellow residue (eluant: n-hexane) gave

only one compound characterized as [Os3(CO)9(l-OH)(l-

H)(g1-PhPC4H2Me2)] (3) (57 mg, 47 %).

Reaction of [Os3(CO)11(CH3CN)] with cyanoethyldi-

tert-butylphosphine

A solution of [Os3(CO)11(CH3CN)] (50 mg, 0.537 mmol)

and cyanoethyldi-tert-butylphosphine (10 mg, 0.537 mmol)

in dried dichloromethane (50 mL) was stirred at room

temperature under nitrogen for 2 h. After evaporation of the

solvent, TLC (SiO2) of the yellow residue (eluant: dichlo-

romethane:hexane, 3:7 v:v) gave one main compound,

[Os3(CO)11(g1-tBu2PC2H4CN)] (4) (30 mg, 45 %).

[Os3(μ-H)2(CO)10] +

1 + 2

ΔCyclohexane

3.5 h

[Os3(CO)9(μ-OH)(μ-H)(η1-PhPC4H2Me2)] (3)

ΔTHF

2 h

1 2a 2b

H

OsOs

-

Os-

PH3C

H3C

(CO)3

(CO)3

(CO)3

H

OsOs

-

Os-

PH3C

H3C

(CO)3

(CO)3

(CO)3

P

H3C

H3C

H

OsOs

-

Os-

PH3C

H3C

(CO)3

(CO)3

(CO)3

Scheme 1 Reaction of [Os3(l-H)2(CO)10] with 3,4-dimethyl-1-phenylphosphole

240 Transition Met Chem (2014) 39:239–246

123

Ta

ble

1S

pec

tro

sco

pic

dat

afo

rco

mp

ou

nd

s1

–4

Co

mp

ou

nd

m(C

O)a

(cm

-1)

NM

Rb

(d,

pp

m)

J(H

z)

31P

13C

{1H

}1H

[Os 3

(CO

) 9(l

-H)(

l3:g

1:g

1:g

2-P

hP

C4H

3M

e 2)]

12

,08

2s

2,0

53

s

2,0

23

s

2,0

11

m

1,9

86

m

1,9

75

w

1,9

65

w

1,9

49

w

-2

3.4

6s

17

7.7

6s,

CO

17

7.3

9s,

CO

17

7.1

6s,

CO

17

6.3

5s,

CO

17

2.7

1s,

CO

17

0.2

9s,

CO

13

9.5

0d

,C

i

13

1.0

5d

,C

p

12

9.0

9d

,C

m

12

8.1

2d

,C

o

12

2.9

8d

,C

3

66

.11

d,

C2

39

.42

d,

C4

29

.38

s,C

H3

18

.80

d,

CH

3*

-1

2.5

1d

,C

1

7.4

4m

,H

m

7.4

4m

,H

p

7.3

4m

,H

o

3.7

3d

dd

d,

H1

3.5

7d

,H

4

2.4

1s,

CH

3

2.3

3s,

H2

0.7

9d

,C

H3*

-1

7.9

4d

,O

sHO

s

H1–

CH

3

6.8

P–

H1

37

.9

P–

H4

23

.9

P–

H(O

s)1

2.7

P–

Ci

6.0

P–

Cp

2.4

P–

Cm

9.0

P–

Co

11

.3

P–

C3

16

.2

P–

C2

4.3

P–

C4

48

.0

P–

CH

36

.8

P–

C1

14

.9

[Os 3

(CO

) 9(H

)(l

2-g

1:g

2-P

hP

C4H

4M

e 2)]

22

,08

2s

2,0

53

s

2,0

23

s

2,0

11

m

1,9

86

m

1,9

75

w

1,9

65

w

1,9

49

w

7.5

0m

,H

m

7.5

0m

,H

p

7.3

0m

,H

o

-2

9.7

0s

-3

8.2

5s

a5

.27

d,

H1

5.2

3d

,H

2

4.5

3s,

H3

3.2

6d

,H

4

2.5

3s,

CH

3

2.3

7s,

CH

3*

-1

8.1

4d

,O

sHO

s

P–

H1

12

.7

P–

H2

12

.5

P–

H4

13

.2

P–

H(O

s)1

2.3

b4

.79

d,

H1

4.7

5d

,H

2

4.6

4s,

H3

3.3

0d

,H

4

2.7

2s,

CH

3

2.2

3s,

CH

3*

-1

5.5

4s,

OsH

P–

H1

13

.4

P–

H2

13

.1

P–

H4

14

.6

Transition Met Chem (2014) 39:239–246 241

123

Ta

ble

1co

nti

nu

ed

Co

mp

ou

nd

m(C

O)a

(cm

-1)

NM

Rb

(d,

pp

m)

J(H

z)

31P

13C

{1H

}1H

[Os 3

(CO

) 9(l

-OH

)(l-

H)(

g1-P

hP

C4H

2M

e 2)]

32

,09

1m

2,0

50

s

2,0

09

s

1,9

86

m

1,9

76

w

1,9

69

m

1,9

45

w

10

.56

s1

84

.88

s,C

O

18

2.5

8d

,C

O

18

2.1

4s,

CO

17

8.5

7d

,C

O

17

7.5

4s,

CO

17

7.4

7d

,C

O

17

4.1

5d

,C

O

17

1.8

0s,

CO

15

5.7

1d

,C

3

15

2.0

3d

,C

2

13

1.2

6d

,C

o

13

1.1

3s,

Cp

12

9.4

0d

,C

m

12

8.6

6d

,C

4

12

7.7

8d

,C

i

12

3.4

5d

,C

1

18

.06

d,

CH

3

17

.58

d,

CH

3*

7.5

5m

,H

o

7.4

5m

,H

m

7.4

5m

,H

p

6.6

2d

,H

4

6.3

5d

,H

1

2.1

6s,

CH

3

2.1

2s,

CH

3*

-1

.05

d,

OH

-1

2.3

8d

,O

sH

P–

H1

32

.2

P–

H4

34

.4

P–

OH

3.3

P–H

(Os)

8.5

P–

CO

4.2

P–

CO

2.8

P–

CO

17

.5

P–

C3

10

.2

P–

C2

9.5

P–

Co

10

.9

P–

Cm

10

.7

P–

C4

49

.9

P–

Ci

52

.6

P–

C1

48

.2

P–

CH

31

1.8

P–

CH

3*

12

.1

[Os 3

(CO

) 11(g

1-t B

u2P

C2H

4C

N)]

c4

2,1

09

w

2,0

58

m

2,0

22

s

2,0

02

w

1,9

82

w

1,9

54

w

1,9

41

w

33

.78

s3

8.4

1d

,C

CH

3

30

.31

s,C

H3

22

.70

d,

C1

15

.54

s,C

2

2.7

1m

,H

2

2.5

7m

,H

1

1.3

6d

,C

H3

P–

CH

31

4.5

P–

C(C

H3)

19

.9

P–

C1

22

.4

aC

6H

12;

bC

DC

l 3(2

0�C

);c

C3(n

itri

le)

isn

ot

ob

serv

ed

242 Transition Met Chem (2014) 39:239–246

123

(CO) 3 Os2-

Os2-

Os2-

H

H(CO) 3

(CO) 4

P

CH3 CH3

Ph

Os2-

Os2-

Os5-

H

H COCO

OC P+

CH3

CH3

Ph

(CO) 4

(CO) 3

- CO

(CO) 4

(CO) 3 Os2-

Os2-

Os5-

H

H

CO

CO

OC

P+

CH3CH3

Ph(CO) 3

(CO)4

(CO) 3

P+

CH3

CH3

Ph

Os2-

Os2-

Os2-

H

H

H

(CO) 3

(CO) 3

(CO) 3

P+

CH3

CH3

Ph

Os2-

Os2-

Os2-

H

1

(CO) 3

(CO) 3

(CO) 3

P+

CH3

CH3

Ph

Os2-

Os2-

Os2-

H

2a

HH

(CO) 3

(CO) 3

(CO) 3

P+

CH3

CH3

Ph

Os2-

Os2-

Os2-

H2b

HH

+ Δ

Scheme 2 Mechanism for the formation of 1, 2a and 2b

Fig. 1 Molecular structure of

[Os3(CO)9(l-OH)(l-H)(g1-

PhPC4H2Me2)] (3), showing

50 % probability ellipsoids

Transition Met Chem (2014) 39:239–246 243

123

Results and discussion

Thermal treatment of [Os3(l-H)2(CO)10] with 3,4-

dimethyl-1-phenylphosphole

The reaction of [Os3(l-H)2(CO)10] with 3,4-dimethyl-1-

phenylphosphole in refluxing cyclohexane gives [Os3(CO)9

(l-H)(l3:g1:g1:g2-PhPC4H3Me2)] (1) in low yield, and in

higher yield two inseparable isomers of formula [Os3(CO)9

(H)(l2-g1:g2-PhPC4H4Me2)] (2) (60 mg, 51 %). When the

reaction is carried out in refluxing THF, only the unsatu-

rated [Os3(CO)9(l-OH)(l-H)(g1-PhPC4H2Me2)] (3) clus-

ter is obtained (Scheme 1). The spectroscopic data for

complex 1 (IR and NMR; Table 1) correspond to a com-

pound previously reported by our research group, obtained

in higher yield (35 %) from the reaction of [Os3(l-H)2

(CO)10] with 3,4-dimethyl-1-phenylphosphole in refluxing

cyclohexane for 6 h [15].

The IR spectrum of complex 2 in the carbonyl region is

characteristic of a nonacarbonyl trinuclear compound

similar to 1; its 31P{1H} NMR spectrum shows two singlets

at d = -29.70 and -38.25 ppm with different intensities,

suggesting the presence of a mixture of isomers (2a, 2b)

which proved to be chromatographically inseparable. The1H NMR spectrum confirms the existence of two deriva-

tives in approximately 7/3 ratio; the signals for both iso-

mers are consistent with partial hydrogenation of a

phosphole ring, such that the methylene protons are not

equivalent and are only coupled to the phosphorus atom.

On the other hand, two hydride signals at d = -15.54 and

-18.14 ppm are observed, which can be attributed to one

terminal and one bridging hydride, respectively. We were

unable to obtain suitable crystals for the X-ray diffraction

analysis of 2; however, based on the spectroscopic evi-

dence and comparison with its analogues [Ru3(CO)9(l-H)

(l-PPh2)] [34] and [Os2(CO)8(l3-g2-Ph2PCH2P(Ph)C6H4)(l-H)]

[35], the two structures shown for 2a and 2b in Scheme 1

are the most likely. Hence, each isomer is a nonacarbonyl

trinuclear osmium derivative with a partially hydrogenated

phosphole ligand, behaving as a four-electron donor: two

electrons are involved in g1-coordination by the phospho-

rus atom, and two more are provided by the coordinated

C=C bond. Both isomers are 47-electron unsaturated

clusters with two 18-electron and one 17-electron osmium

atoms. The difference between the two compounds is due

to the terminal or bridging coordination of the hydride

ligand. It seems likely that complex 2 is an intermediate

for the formation of complex 1, since increasing the

reaction time gives a better yield of complex 1, while

complex 2 is no longer observed, as reported previously

[15]. With the aim to better understand the formation of

the hydrogenated complex 1, we carried out the reaction

for a shorter period of time in refluxing cyclohexane,

obtaining two new compounds (2a, 2b) which are isomeric

and show fluxional behavior in the NMR time scale. We

believe that the formation of complexes 1, 2a and 2b can

be explained by the migration of a hydride from the

osmium atom to the unsaturated coordinated phosphole

ring, as shown in Scheme 2.

Complex 3 shows an IR spectrum similar to the one found

for [Os3(l-H)(l-OH)(CO)9(PMe2Ph)] [36], obtained from

Os

Os Os(CO)3

P

N

H3C

H3C

H3C

CH3

H3CH3C

[Os3(CO)11(CH3CN)] +25 ºC, 2 h

N

(t-Bu)2PCH2Cl2

4

(CO)4

(CO)4

Scheme 3 Reaction of [Os3(CO)11(CH3CN)] with cyanoethyldi-tert-butylphosphine

Table 2 Selected bond lengths (A) and angles (�) for compounds 3and 4

[Os3(CO)9(l-OH)

(l-H)(g1-PhPC4H2

Me2)] (3)

[Os3(CO)11(g1-tBu2

PC2H4CN)] (4)

Os1–Os2 2.790 (1) Os1–Os2 2.9384 (13)

Os1–Os3 2.818 (1) Os1–Os3 2.9022 (12)

Os2–Os3 2.821 (2) Os2–Os3 2.8770 (13)

P4–Os2 2.349 (7) Os1–P1 2.394 (5)

Os2–O1 2.227 (2) N1–C3 1.12 (3)

Os1–O1 2.089 (2) P1–Os1–Os3 176.13 (15)

P4–Os2–Os1 104.8 (2) P1–Os1–Os2 119.83 (14)

P4–Os2–Os3 165.0 (2) Os3–Os1–Os2 59.02 (3)

Os2–Os3–C34A 157.3 (8) Os3–Os2–Os1 59.86 (3)

Os1–O1–Os2 80.5 (6) Os2–Os3–Os1 61.12 (3)

Os2–Os1–O1 51.9 (5)

Os1–Os2–O1 47.6 (4)

Os2–Os1–Os3 60.4 (3)

Os1–Os2–Os3 60.3 (3)

Os1–Os3–Os2 59.3 (3)

C32A–Os3–C34A 169.7 (8)

Os3–Os1–C12A 91.9 (1)

Os1–Os3–C32A 84.9 (1)

244 Transition Met Chem (2014) 39:239–246

123

the reaction of [Os3H2(CO)9(PMe2Ph)] with H2O. Its 1H and13C NMR spectra show very small differences compared

with those of the free ligand, suggesting P-bonding of the

phosphole, but the protons for the phosphole ring are non-

equivalent. Additionally, the 1H NMR spectrum shows two

doublets at d = -1.05 and -12.38 ppm, associated with a

bridging hydroxyl and bridging hydride ligand, respectively.

An X-ray structure determination for complex 3 was carried

out; an ORTEP view of the molecule is shown in Fig. 1, and

bond lengths and angles are given in Table 2. The molecular

structure consists of a nonacarbonyl osmium triangle with

the phosphole ligand coordinated through the phosphorus

atom, acting as a two-electron donor. The phosphole ligand

is coordinated to Os2, occupying an equatorial site as

expected, and the Os2–P (2.349(7) A) bond distance is close

to the values found in other related triosmium clusters [36].

The Os1–Os2 edge of the triangle is asymmetrically bridged

by a OH group (Os1–O1 = 2.089(2) A and Os2–

O1 = 2.227(2) A) unlike those reported for [Os3(l-H)(l-

OH)(CO)9(PMe2Ph)] [36] where the two Os–OH distances

are quite similar (Os1–OH = 2.118(5) A and Os3–

OH = 2.135(5) A). The hydride ligand was not located but

structural details indicate that it lies along the Os1–Os2

bond, which is the shortest of the three Os–Os bonds [Os1–

Os2 = 2.790(1) A, Os1–Os3 = 2.818(1) A and Os2–

Os3 = 2.821(2) A]. The OH group located near the C3 and

C4 atoms gives rise to different chemical shifts in the 1H and13C NMR spectra for the phosphole ring, due to the restricted

rotation around the Os–P bond. It is probable that the OH

group comes from a contaminant, presumably moisture from

THF. In spite of repeated efforts, we were unable to establish

and/or eliminate the source of the OH group.

Thermal treatment of [Os3(CO)11(CH3CN)]

with cyanoethyldi-tert-butylphosphine

Reaction of [Os3(CO)11(CH3CN)] with cyanoethyldi-tert-

butylphosphine gives one main compound characterized as

[Os3(CO)11(g1-tBu2PC2H4CN)] (4) in high yield

(Scheme 3). Complex 4 is closely related spectroscopically

to known mono-substituted triosmium and triruthenium

cluster analogs [15, 37–40]. The molecular structure of

complex 4 was confirmed by an X-ray crystallographic

study (Fig. 2), and selected bond lengths and angles are

given in Table 2. The phosphine ligand is coordinated

through the phosphorus atom, occupying a sterically pre-

ferred equatorial site in the triangular metal cluster. The

Os–Os bond distances (Os1–Os2 = 2.9384(13) A, Os1–

Os3 = 2.9022(12) A, Os2–Os3 = 2.8770(13) A) are sim-

ilar to those found for the analogous [Os3(CO)11(g1-PR3)]

[39–41]. The N1–C15 bond length of 1.12(3) A is as

expected and very similar to those reported for non-coor-

dinated CN groups [42].

Conclusions

The work described here provides a new example of the

reactivity of the unsaturated [Os3(l-H)2(CO)10] and the

labile [Os3(CO)11(CH3CN)] clusters with phosphole and

Fig. 2 Molecular structure of

[Os3(CO)11(g1-tBu2PC2H4CN)]

(4), showing 50 % probability

ellipsoids

Transition Met Chem (2014) 39:239–246 245

123

phosphine ligands. We have found that the reaction of

[Os3(l-H)2(CO)10] with 3,4-dimethyl-1-phenylphosphole

leads to different products when carried out in different

solvents, cyclohexane or THF. A new nonacarbonyl trios-

mium cluster containing a partially hydrogenated phosp-

hole ligand was obtained from the reaction in cyclohexane

(complex 2), where the phosphole ligand behaves as a four-

electron donor: two electrons are provided by g1-coordi-

nation of the phosphorus atom and two electrons from the

coordinated C–C double bond. In contrast, when THF was

used as the solvent, only single coordination through the

phosphorus atom was observed (complex 3), and an

asymmetrically bridged OH ligand was provided from the

reaction medium. Meanwhile, interaction between the

labile cluster [Os3(CO)11(CH3CN)] and cyanoethyldi-tert-

butylphosphine yielded only one product (complex 4) in

which the phosphine ligand is bound to a metal center by

the phosphorus atom occupying an equatorial position.

Supplementary material

CCDC 957526 and 957525 contain the supplementary

crystallographic data for compounds 3 and 4, respectively.

These data can be obtained free of charge from The

Cambridge Crystallographic Data Center via www.ccdc.

cam.ac.uk/data_request/cif.

Acknowledgments We thank FONACIT for project G-20050000447

and to Laboratorio Nacional de Difraccion de Rayos-X, project LAB-

97000821.

References

1. Alley WM, Hamdemir IK, Wang Q, Frenkel AI, Li L, Yang JC,

Menard LD, Nuzzo RG, Oszkar S, Johnson KA, Finke RG (2010)

Inorg Chem 49:8131–8147

2. Yih K, Hamdemir IK, Mondloch JE, Bayram E, Ozkar S, Vasic

R, Frenkel AI, Anderson OP, Finke RG (2012) Inorg Chem

51:3186–3193

3. Fryzuk MD (1982) Organometallics 1:408–409

4. Sivak AJ, Muetterties EL (1979) J Am Chem Soc 101:4878–4887

5. Kulzick M, Price T, Muetterties EL, Day VW (1982) Organo-

metallics 1:1256–1258

6. Li C, Leong WK (2008) J Organomet Chem 693:1292–1300

7. Abe M, Michi T, Sato A, Kondo T, Zhou W, Ye S, Uosaki K,

Sasaki Y (2003) Angew Chem Int Ed 42:2912–2915

8. Huttner G, Schneider J, Muller H, Mohr G, Seyerl J, Wohlfahrt L

(1979) Angew Chem Int Ed Engl 18:76–77

9. Richter F, Vahrenkamp H (1982) Organometallics 1:756–757

10. Braunstein P, Rose J (1989) In: Bernal I (ed) Chemical bonds:

better ways tomake them and break them, vol 3. Elseiver,

Strasbourg, p 3

11. Braunstein P (1991) Mater Chem Phys 29:33–63

12. Bruce MI, Matisons JG, Rodgers JR, Wallis RC (1981) J Chem

Soc Chem Commun 20:1070–1071

13. Farrar DH, Jackson PF, Johnson BFG, Lewis J, Nicholls JKN,

McPartlin M (1981) J Chem Soc Chem Commun 9:415–416

14. Adams RD, Chen MI, Yang X (2012) Organometallics

31:3588–3598

15. Arce AJ, De Sanctis Y, Goite MC, Machado R, Otero Y, Gon-

zalez T (2012) Inorg Chim Acta 392:241–245

16. Arce AJ, De Sanctis Y, Manzur J, Deeming AJ, Powell NI (1991)

J Organomet Chem 408:C18–C21

17. Roberto D, Lucenti E, Roveda C, Ugo R (1997) Organometallics

16:5974–5980

18. Deeming AJ, Hasso S, Underhil M (1975) J Chem Soc Dalton

Trans 15:1614–1620

19. Jackson W, Johnson BFG, Kelland JW, Lewis J, Schorpp KT

(1975) J Organomet Chem 87:C27–C30

20. Keister JB, Shapley JR (1975) J Organomet Chem 85:C29–C31

21. Kahlal S, Udachin KA, Scoles L, Carty AJ, Saillard J (2000)

Organometallics 19:2251–2257

22. Wang W, Corrigan JF, Enright GD, Taylor NJ, Carty AJ (1998)

Organometallics 17:427–432

23. Vahrenkamp H, Wolters D (1982) Organometallics 1:874–875

24. Jaeger T, Aime S, Vahrenkamp H (1986) Organometallics

5:245–252

25. Lin Q, Leong WK (2003) Organometallics 22:3639–3648

26. Deeming AJ, Powell N, Arce AJ, De Sanctis Y, Manzur J (1991)

J Chem Soc Dalton Trans 12:3381–3386

27. Arce AJ, Machado R, De Sanctis Y, Gonzalez T, Atencio R,

Deeming AJ (2003) Inorg Chim Acta 344:123–127

28. Kaesz H (1971) J Chem Soc Chem Commun 10:477–477

29. Nicholls JN, Vargas MD (1989) Inorg Synth 26:289–293

30. Breque A, Mathey F (1981) Synthesis 12:983–985

31. Karsch HH, Hermann WA (1996) Synthetic methods of organo-

metallic and inorganic chemistry: phosphorus, arsenic, antimony

and bismuth, vol 3. Thieme, Richmond

32. Wolfsberger W, Burkart W, Werner H (1992) Z Naturforsch, B:

Chem Sci 47:155–159

33. Perrın D, Amarego W (1988) Purification of laboratory chemi-

cals. Pergamon Press, England

34. MacLaughlin S, Taylor N, Carty A (1984) Organometallics

3:392–399

35. Kabir S, Miah A, Sarker N, Hussain G, Hardcastle K, Nordlander

E, Rosenberg E (2005) Organometallics 24:3315–3320

36. Deeming A, Manning PJ, Rothwell IP, Hursthouse MB, Walker

NPC (1984) J Chem Soc Dalton Trans 9:2039–2045

37. Thapper A, Sparr E, Johnson BFG, Lewis J, Raithby PR, Nord-

lander E (2004) Inorg Chem Commun 7:443–446

38. Johnson BFG, Lewis J, Pippard DA (1981) J Chem Soc Dalton

Trans 2:407–412

39. Bruce MI, Liddell MJ, Hughes CA, Patrick JM, Skelton BW

(1988) J Organomet Chem 347:157–180

40. Johnson BFG, Lewis J, Nordlander E, Raithby PR (1996) J Chem

Soc Dalton Trans 19:3825–3831

41. Hansen VM, Ma AK, Biradha K, Pomeroy RK, Zaworotko MJ

(1998) Organometallics 17:5267–5274

42. Allen FH, Kennard O, Watson DG, Brammer L, Orpen AG,

Taylor R (1987) J Chem Soc Perkin Trans 2:S1–S19

246 Transition Met Chem (2014) 39:239–246

123