Regiospecificity in reactions of alkynes and phosphines with the phosphido-bridged iron-cobalt complex [(OC)4Fe(μ-PPh2)Co(CO)3]

Jason D. King; Martin J. Mays; Chi Yu Mo; Paul R. Raithby; Moira A. Rennie; Gregory A. Solan; Trushar Adatia; Gráinne Conole

doi:10.1016/S0022-328X(00)00082-6

Regiospecificity in reactions of alkynes and phosphines with the phosphido-bridged iron-cobalt complex [(OC)₄Fe(μ-PPh₂)Co(CO)₃]

Jason D. King, Martin J. Mays, Chi Yu Mo, Paul R. Raithby, Moira A. Rennie, Gregory A. Solan, Trushar Adatia, Gráinne Conole

Department of Chemistry

Research output: Contribution to journal › Article › peer-review

16 Citations (SciVal)

Abstract

The iron-cobalt phosphido-bridged complex [(OC)₄Fe(μ-PPh₂)Co(CO)₃] (1) can be prepared conveniently and in good yield from the reaction of [Co₂(μ-PPh₂)₂(CO)₆] with [Fe(CO)₅]. A study of the reactivity of 1 towards symmetrical and unsymmetrical alkynes, R¹CCR² (R¹=R²=CO₂Me, Ph; R¹=H, R²=Ph), has been undertaken. In all cases, five-membered ferracycle-containing products of the type [(OC)₃Fe{μ-PPh₂C(O)CR¹CR ²}Co(CO)₃] (R¹=R²=CO₂Me (2a), Ph (2c); R¹=H, R²=Ph (2b)), are initially obtained in which a molecule of CO and a molecule of R¹CCR² have been inserted regiospecifically into a Co-P bond in 1. Decarbonylation of 2a occurs during its preparation or in low yield on its thermolysis to give the four-membered ferracyclic species [(OC)₃Fe{μ-PPh₂C(CO₂Me)C(CO ₂Me)}Co(CO)₃] (3a). Similar thermolysis of 2b results not only in the related decarbonylation product [(OC)₃Fe(μ-PPh₂CHCPh)Co(CO)₃] (3b), but additionally in three other products all in low yield, namely the regioisomer of 3b, [(OC)₃Fe(μ-PPh₂CPhCH)Co(CO)₃] (4b), the aldehyde-substituted complex [(OC)₃Fe{μ-PPh₂C(CHO)CPh}Co(CO)₃] (5b) and the five-membered ferracycle-containing species [(OC)₃Fe{μ-PPh₂CHCPhC(O)}Co(CO)₃] (6b). Treatment of 2a and 2b with PPhMe₂ and P(OMe)₃ results in substitution of an iron-bound carbonyl group to give, respectively, [(PhMe₂P)(OC)₂Fe{μ-PPh₂C(O)C(CO ₂Me)C(CO₂Me)}(μ-CO)Co(CO)₂] (7a) and [{(MeO)₃P}(OC)₂Fe{μ-PPh ₂C(O)CHCPh}(μ-CO)Co(CO)₂] (7b) in high yield. In contrast, substitution of a cobalt-bound carbonyl is achieved on reaction of 3a with PPhMe₂ or PPh₂H to give [(OC)₃Fe{μ-PPh₂C(CO₂Me)C(CO ₂Me)}Co(CO)₂(L)] (L=PPhMe₂ (8a), PPh₂H (9a)). Thermolysis of the secondary phosphine-substituted complex 9a results in phosphorus-hydrogen bond cleavage to give [(OC)₃Fe{μ-PPh₂C(CO₂Me)CH(CO ₂Me)}(μ-PPh₂)Co(CO)₂] (10a). Single-crystal X-ray diffraction studies have been performed on complexes 7b, 8a and 10a.

Original language	English
Pages (from-to)	271-283
Number of pages	13
Journal	Journal of Organometallic Chemistry
Volume	601
Issue number	2
DOIs	https://doi.org/10.1016/S0022-328X(00)00082-6
Publication status	Published - 28 Apr 2000

Funding

This work was supported by the EPSRC (grant to C.-Y.M.).

Keywords

Alkyne
Cobalt
Dinuclear
Iron
Phosphido
Phosphine

ASJC Scopus subject areas

Biochemistry
Physical and Theoretical Chemistry
Organic Chemistry
Inorganic Chemistry
Materials Chemistry

Access to Document

10.1016/S0022-328X(00)00082-6

Cite this

@article{b8bd737eca29405c8395e2cec2bd2687,

title = "Regiospecificity in reactions of alkynes and phosphines with the phosphido-bridged iron-cobalt complex [(OC)4Fe(μ-PPh2)Co(CO)3]",

abstract = "The iron-cobalt phosphido-bridged complex [(OC)4Fe(μ-PPh2)Co(CO)3] (1) can be prepared conveniently and in good yield from the reaction of [Co2(μ-PPh2)2(CO)6] with [Fe(CO)5]. A study of the reactivity of 1 towards symmetrical and unsymmetrical alkynes, R1CCR2 (R1=R2=CO2Me, Ph; R1=H, R2=Ph), has been undertaken. In all cases, five-membered ferracycle-containing products of the type [(OC)3Fe{μ-PPh2C(O)CR1CR 2}Co(CO)3] (R1=R2=CO2Me (2a), Ph (2c); R1=H, R2=Ph (2b)), are initially obtained in which a molecule of CO and a molecule of R1CCR2 have been inserted regiospecifically into a Co-P bond in 1. Decarbonylation of 2a occurs during its preparation or in low yield on its thermolysis to give the four-membered ferracyclic species [(OC)3Fe{μ-PPh2C(CO2Me)C(CO 2Me)}Co(CO)3] (3a). Similar thermolysis of 2b results not only in the related decarbonylation product [(OC)3Fe(μ-PPh2CHCPh)Co(CO)3] (3b), but additionally in three other products all in low yield, namely the regioisomer of 3b, [(OC)3Fe(μ-PPh2CPhCH)Co(CO)3] (4b), the aldehyde-substituted complex [(OC)3Fe{μ-PPh2C(CHO)CPh}Co(CO)3] (5b) and the five-membered ferracycle-containing species [(OC)3Fe{μ-PPh2CHCPhC(O)}Co(CO)3] (6b). Treatment of 2a and 2b with PPhMe2 and P(OMe)3 results in substitution of an iron-bound carbonyl group to give, respectively, [(PhMe2P)(OC)2Fe{μ-PPh2C(O)C(CO 2Me)C(CO2Me)}(μ-CO)Co(CO)2] (7a) and [{(MeO)3P}(OC)2Fe{μ-PPh 2C(O)CHCPh}(μ-CO)Co(CO)2] (7b) in high yield. In contrast, substitution of a cobalt-bound carbonyl is achieved on reaction of 3a with PPhMe2 or PPh2H to give [(OC)3Fe{μ-PPh2C(CO2Me)C(CO 2Me)}Co(CO)2(L)] (L=PPhMe2 (8a), PPh2H (9a)). Thermolysis of the secondary phosphine-substituted complex 9a results in phosphorus-hydrogen bond cleavage to give [(OC)3Fe{μ-PPh2C(CO2Me)CH(CO 2Me)}(μ-PPh2)Co(CO)2] (10a). Single-crystal X-ray diffraction studies have been performed on complexes 7b, 8a and 10a.",

keywords = "Alkyne, Cobalt, Dinuclear, Iron, Phosphido, Phosphine",

author = "King, {Jason D.} and Mays, {Martin J.} and Mo, {Chi Yu} and Raithby, {Paul R.} and Rennie, {Moira A.} and Solan, {Gregory A.} and Trushar Adatia and Gr{\'a}inne Conole",

year = "2000",

month = apr,

day = "28",

doi = "10.1016/S0022-328X(00)00082-6",

language = "English",

volume = "601",

pages = "271--283",

journal = "Journal of Organometallic Chemistry",

issn = "0022-328X",

publisher = "Elsevier B.V.",

number = "2",

}

TY - JOUR

T1 - Regiospecificity in reactions of alkynes and phosphines with the phosphido-bridged iron-cobalt complex [(OC)4Fe(μ-PPh2)Co(CO)3]

AU - King, Jason D.

AU - Mays, Martin J.

AU - Mo, Chi Yu

AU - Raithby, Paul R.

AU - Rennie, Moira A.

AU - Solan, Gregory A.

AU - Adatia, Trushar

AU - Conole, Gráinne

PY - 2000/4/28

Y1 - 2000/4/28

N2 - The iron-cobalt phosphido-bridged complex [(OC)4Fe(μ-PPh2)Co(CO)3] (1) can be prepared conveniently and in good yield from the reaction of [Co2(μ-PPh2)2(CO)6] with [Fe(CO)5]. A study of the reactivity of 1 towards symmetrical and unsymmetrical alkynes, R1CCR2 (R1=R2=CO2Me, Ph; R1=H, R2=Ph), has been undertaken. In all cases, five-membered ferracycle-containing products of the type [(OC)3Fe{μ-PPh2C(O)CR1CR 2}Co(CO)3] (R1=R2=CO2Me (2a), Ph (2c); R1=H, R2=Ph (2b)), are initially obtained in which a molecule of CO and a molecule of R1CCR2 have been inserted regiospecifically into a Co-P bond in 1. Decarbonylation of 2a occurs during its preparation or in low yield on its thermolysis to give the four-membered ferracyclic species [(OC)3Fe{μ-PPh2C(CO2Me)C(CO 2Me)}Co(CO)3] (3a). Similar thermolysis of 2b results not only in the related decarbonylation product [(OC)3Fe(μ-PPh2CHCPh)Co(CO)3] (3b), but additionally in three other products all in low yield, namely the regioisomer of 3b, [(OC)3Fe(μ-PPh2CPhCH)Co(CO)3] (4b), the aldehyde-substituted complex [(OC)3Fe{μ-PPh2C(CHO)CPh}Co(CO)3] (5b) and the five-membered ferracycle-containing species [(OC)3Fe{μ-PPh2CHCPhC(O)}Co(CO)3] (6b). Treatment of 2a and 2b with PPhMe2 and P(OMe)3 results in substitution of an iron-bound carbonyl group to give, respectively, [(PhMe2P)(OC)2Fe{μ-PPh2C(O)C(CO 2Me)C(CO2Me)}(μ-CO)Co(CO)2] (7a) and [{(MeO)3P}(OC)2Fe{μ-PPh 2C(O)CHCPh}(μ-CO)Co(CO)2] (7b) in high yield. In contrast, substitution of a cobalt-bound carbonyl is achieved on reaction of 3a with PPhMe2 or PPh2H to give [(OC)3Fe{μ-PPh2C(CO2Me)C(CO 2Me)}Co(CO)2(L)] (L=PPhMe2 (8a), PPh2H (9a)). Thermolysis of the secondary phosphine-substituted complex 9a results in phosphorus-hydrogen bond cleavage to give [(OC)3Fe{μ-PPh2C(CO2Me)CH(CO 2Me)}(μ-PPh2)Co(CO)2] (10a). Single-crystal X-ray diffraction studies have been performed on complexes 7b, 8a and 10a.

AB - The iron-cobalt phosphido-bridged complex [(OC)4Fe(μ-PPh2)Co(CO)3] (1) can be prepared conveniently and in good yield from the reaction of [Co2(μ-PPh2)2(CO)6] with [Fe(CO)5]. A study of the reactivity of 1 towards symmetrical and unsymmetrical alkynes, R1CCR2 (R1=R2=CO2Me, Ph; R1=H, R2=Ph), has been undertaken. In all cases, five-membered ferracycle-containing products of the type [(OC)3Fe{μ-PPh2C(O)CR1CR 2}Co(CO)3] (R1=R2=CO2Me (2a), Ph (2c); R1=H, R2=Ph (2b)), are initially obtained in which a molecule of CO and a molecule of R1CCR2 have been inserted regiospecifically into a Co-P bond in 1. Decarbonylation of 2a occurs during its preparation or in low yield on its thermolysis to give the four-membered ferracyclic species [(OC)3Fe{μ-PPh2C(CO2Me)C(CO 2Me)}Co(CO)3] (3a). Similar thermolysis of 2b results not only in the related decarbonylation product [(OC)3Fe(μ-PPh2CHCPh)Co(CO)3] (3b), but additionally in three other products all in low yield, namely the regioisomer of 3b, [(OC)3Fe(μ-PPh2CPhCH)Co(CO)3] (4b), the aldehyde-substituted complex [(OC)3Fe{μ-PPh2C(CHO)CPh}Co(CO)3] (5b) and the five-membered ferracycle-containing species [(OC)3Fe{μ-PPh2CHCPhC(O)}Co(CO)3] (6b). Treatment of 2a and 2b with PPhMe2 and P(OMe)3 results in substitution of an iron-bound carbonyl group to give, respectively, [(PhMe2P)(OC)2Fe{μ-PPh2C(O)C(CO 2Me)C(CO2Me)}(μ-CO)Co(CO)2] (7a) and [{(MeO)3P}(OC)2Fe{μ-PPh 2C(O)CHCPh}(μ-CO)Co(CO)2] (7b) in high yield. In contrast, substitution of a cobalt-bound carbonyl is achieved on reaction of 3a with PPhMe2 or PPh2H to give [(OC)3Fe{μ-PPh2C(CO2Me)C(CO 2Me)}Co(CO)2(L)] (L=PPhMe2 (8a), PPh2H (9a)). Thermolysis of the secondary phosphine-substituted complex 9a results in phosphorus-hydrogen bond cleavage to give [(OC)3Fe{μ-PPh2C(CO2Me)CH(CO 2Me)}(μ-PPh2)Co(CO)2] (10a). Single-crystal X-ray diffraction studies have been performed on complexes 7b, 8a and 10a.

KW - Alkyne

KW - Cobalt

KW - Dinuclear

KW - Iron

KW - Phosphido

KW - Phosphine

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U2 - 10.1016/S0022-328X(00)00082-6

DO - 10.1016/S0022-328X(00)00082-6

M3 - Article

AN - SCOPUS:0000870803

SN - 0022-328X

VL - 601

SP - 271

EP - 283

JO - Journal of Organometallic Chemistry

JF - Journal of Organometallic Chemistry

IS - 2

ER -