Paul A. Humphrey

A novel methodology for the synthesis of complexes containing long carbon chains linking metal centres: molecular structures of {Ru(dppe)Cp*}2(μ-C14) and {Co3(μ-dppm)(CO)7}2(μ3:μ3-C16)

Elimination of AuX(PR3)(X = halogen, R = Ph, tol) occurs readily in reactions between compounds containing C(sp)- or C(sp2)-X bonds and alkynyl or polyynyl gold(I) complexes; this reaction has been applied to the syntheses of complexes containing a variety of metal centres linked by C(n) chains (n up to 16).

Cluster chemistry: XC. Some complexes obtained from reactions between M3(CO)12 (M = Ru or Os) or Ru3(μ-dppm)(CO)10 and 2-substituted triphenylphosphines and related keto-phosphine ligands☆

Several complexes of the type M3Ln{PR2(C6H4X)} [M3Ln= (Ru/Os3(CO)11 or RU3(μ-dppm)(CO)9; X=NH2, NHCOPh, N=CHPh, CHO or CH=NNHAr, but not all combinations] have been prepared and their reactions studied. Predominant were H-migrations from the ary] substituent X to cluster; less facile were CC bond cleavage reactions, and PC bond cleavages were not observed. Under the conditions used, the complexes Ru3(CO)11{PPh2(C6H4X-2)} were transient intermediates in the formation of RU3(μ-H) {μ-PPh2(C6H4(XH)-2)}(CO)9; the analogous Ru3(μ-dppm) and Os3(μ-dppm) complexes were more robust. Similar reactions were found for clusters made by reaction of RU3(CO)12 and related complexes with PPh{2{CH2C(O)Ph}}, in which H-migration from the ligand to the cluster results in formation of a phosphino-enolate system. X-ray structures are reported for the complexes Os3(CO)11{PPh2(C6H4X-2)} [X = NH2, NHC(O)Ph, CHO, CH=NNHC6H3(NO2)2-2,4], Ru3(μ-dppm) (CO)9{PPh 2(C6H4X-2)} [X = NHC(O)Ph, CHO], Ru3(μ-H)(μ-PPh2(C6H4Y-2)(CO)9 [Y = NH, NC(Ph)O, N=CPh], Ru3(μ-H) (μ-) PPh2[C6H4NC(Ph)O-2](μ-dppm)(CO)7, Ru3(μ-H)(μ-dppm)(μ-PPh2(C6H4NH-2)(CO)7 and Os3(μ-H){(μ-PPh) 2(C6H4 CO-2)}(CO)9.

Cluster chemistry: LXXXII. Reactions between Ru3(μ-dppm)(CO)10 and 1-alkynes and related chemistry. Crystal structures of Ru3(μ-H)(μ3-C2C6F5)(μ-dppm)(CO)7, Ru3{μ3-PPhCH2PPh(C6H4))}(μ-C4H2Ph2)(CO)6, AuRu3(μ3-C2Ph)(μ-dppm)(CO)7{P(C6H4Me-p)3} and Ru2(μ-I)(μ-dppm)(μ-C2Ph)(CO)4

Abstract Reactions between Ru3(μ-dppm)(CO)10 (1) and 1-alkynes, HC2R (R = Ph, tBu, SiMe3, C6F5), have given 75–90% yields of Ru3(μ-H)(μ3-C2R)(μ-dppm)(CO)7 (3–6); the related complexes Ru3(μ-H)(μ3C2Ph)(μ-dppm)(CO)6(PPh3) and Ru3(μ-H)(μ3-C2Ph)(μ-dpam)(CO)7 have also been obtained, while addition of Au(C2Ph)(PR3) to 1 gave AuRu3(μ3-C2Ph)(μ-dppm)(CO)7(PR3) (R = Ph, 10; C6H4Me-p, 11). A reaction between Ru3(μ3-PPhCH2PPh(C6H4)(CO)9 and HC2Ph afforded Ru3{μ3-PPhCH2PPh(C6H4)}(μ-C4H2Ph2)(CO)6 (9), containing a metallacyclopentadiene unit. The complex Ru2(μ-I)(μ-dppm)(μ-C2Ph)(CO)4 (12) was obtained by treating 3 with I2. The molecular structures of 6, 9, 11 and 12 were determined by single-crystal X-ray studies.

Reactions of transition metal acetylides: VI. Some addition reactions of substituted styrenes with Ru(C2R)(L)2(η-C5H5) (R = Me OR Ph; L2 = (CO, PPh3), (PPh3)2 OR (dppe)). X-ray crystal structure of Ru{C[C(CN)2]CPhCH(C6H4NO2-4)}(dppe)(η-C5H5) · 0.5CH2Cl2

Abstract Further studies of the reactions between ruthenium σ-acetylide complexes and electrophilic olefins CHArC(CN)(X) (Ar = C 6 H 4 NO 2 -4, Ph; X = CN; Ar = C 6 H 4 NO 2 -4, X = CO 2 Et) have shown the formation of allylic, butadienyl, and in one case, cyclobutenyl complexes. The direction of addition is such that the =C(CN)(X) group becomes attached to the α-carbon of the acetylide. This is confirmed by the X-ray structure of Ru{C[C(CN) 2 ]CPhCH(C 6 H 4 NO 2 -4)}(dppe)(η-C 5 H 5 ) · 0.5CH 2 Cl 2 , cr with cell dimensions a 28.81(1), b 9.661(2), c 30.782(8) A, β 95.02 (3)°, and Z = 8. The structure was refined by a least-squares procedure with the use of 4291 statistically significant reflections [ I > 2.5σ( I )] to R 0.075 and R w 0.076.

Cluster chemistry: LXXXI. Reactions of Ru3(μ-dppm)(CO)10 with C2(CO2Me)2. X-ray structures of Ru3{μ3-C4(CO2Me)4}(μ-dppm)(CO)6, Ru3(μ-H)2{μ3-C2(CO2Me)2}(μ-dppm)(CO)7 and Ru4(μ3-H){μ-C2(CO2Me)2}{μ-PPh2CH2PPh(C6H4)}(CO)9☆

Abstract Several complexes have been obtained from reactions between Ru 3 (μ-dppm)(CO) 10 and C 2 (CO 2 Me) 2 , including Ru 3 {μ 3 -C 2 (CO 2 Me) 2 }(μ-dppm)(μ-CO)(CO) 7 (7), Ru 3 {μ 3 -C 4 (CO 2 Me) 4 }(μ-dppm)(CO) 6 , ( 8 ), Ru 4 (μ 4 -C 2 )(CO 2 Me) 2 }(μ-dppm)(CO) 10 ( 11 ) and Ru 4 (μ 3 -H){μ 4 -C 2 (CO 2 Me) 2 }{μ-PPh 2 CH 2 PPh(C 6 H 4 )}(CO) 9 ( 10 ). A complex related to 10 , containing a C 4 (CO 2 Me) 4 ligand, was obtained directly from Ru 3 (μ 3 -PPhCH 2 PPh(C 6 H 4 )}(CO) 9 and the alkyne. Ready replacement of CO by 2H occurred in the reaction of 7 with H 2 , which afforded Ru 3 (μ-H) 2 {μ 3 -C 2 (CO 2 Me) 2 }(μ-dppm)(CO) 7 ( 9 ). Complexes 8 , 9 and 10 were characterised by single-crystal X-ray studies: in 8 , the C 4 (CO 2 Me) 4 ligand forms a ruthenacyclopentadiene system which interacts in the η 4 mode with the second Ru atom, and via an ester CO group with the third Ru atom. In 9 , the alkyne is attached to the Ru 3 cluster in the μ 3 -η 2 -|| mode, while in 10 , it is incorporated into an octahedral C 2 Ru 4 cluster; the metallated dppm ligand bridges an edge of one of the wings of the Ru 4 butterfly. Complexes 10 and 11 were obtained in only 1% and 2% yield, respectively.

A novel method of introducing the Au2(PR3)2 (R = Ph, OMe) unit into metal clusters X-ray structures of three complexes containing Au2Ru3 cores and of Ru6C(μ-CO)2(CO)14 {Au(PPh3)}2

Abstract The complexes Ru 3 ( μ 3 -C 6 H 3 R){ μ -P(C 6 H 4 R-3) 2 } 2 (CO) 6 {Au 2 (PPh 3 ) 2 } (R = H ( 2 ), Me), Ru 3 {μ 3 -PPhCH 2 PPh(C 6 H 4 -2)}(CO) 8 -{Au 2 (PR 3 ) 2 } ( R = Ph , OMe (5)), Ru 3 (μ 3 -NPh) n (CO) 10−n {Au 2 (PPh 3 ) 2 } ( n = 1 ( 6 ), 2) and Ru 3 ( μ 3 -S) 2 (CO) 8 {Au 2 (PPh 3 ) 2 } have been obtained from reactions between [O{Au(PR 3 )} 3 ] + (R = Ph, OMe) and the ‘parent’ Ru 3 clusters; X-ray structural studies of 2 , 5 and 6 show that a CO group has been replaced by an Au 2 (PR 3 ) 2 fragment. In contrast, the two Au(PPh 3 ) groups bridge opposite RuRu bonds in Ru 6 C(μ-CO) 2 (CO) 14 {Au(PPh 3 )} 2 ( 9 ; X-ray structure). The known complexes Os 3 (CO) 11 {Au 2 (PPh 3 ) 2 }, and Os 3 H 2− n (CO) 10 - {Au(PPh 3 )} n ( n = 1, 2) were obtained from Os 3 (CO) 12 and Os 3 H 2 (CO) 10 respectively.

FURTHER OBSERVATIONS ON THE DIMERISATION OF ALKYNES ON TRIRUTHENIUM CLUSTERS

The reaction between Ru 3 { μ 3 -PPhCH 2 PPh(C 6 H 4 )}(CO) 9 ( 2 ) and HC 2 Ph resulted in insertion of a diene formed by coupling of the alkyne into an Ru–P(phosphido) bond to give a PPh(C 6 H 4 )CH 2 PPh(C 4 H 2 Ph 2 ) ligand. Thermolysis regenerated the original phosphido–phosphine ligand and the alkyne dimer, which was coordinated in the usual 2 η 1 : η 4 -mode. Similar metallacyclopentadiene complexes were obtained from 2 and HC 2 CO 2 Me, from Ru 3 { μ 3 -RC 2 (CO 2 Me)}( μ -dppm)( μ -CO)(CO) 7 and C 2 Ph 2 [R=CO 2 Me, H (2 isomers)], and from [Ru 3 ( μ 3 -PPhCH 2 PPh 2 )(CO) 9 ] − and C 2 Ph 2 , followed by protonation. X-ray structures are reported for the complexes Ru 3 { μ 3 -C 2 Ph 2 C 2 (CO 2 Me) 2 }( μ -dppm)(CO) 6 ( 5 ) and two isomers of Ru 3 { μ 3 -C 2 Ph 2 CHC(CO 2 Me)}( μ -dppm)(CO) 6 ( 8a and 8b ), Ru 3 { μ 3 -PPh(C 6 H 4 )CH 2 PPh(C 4 H 2 Ph 2 )}( μ -CO)(CO) 6 ( 9 ) and Ru 3 ( μ -H)( μ 3 -PPhCH 2 PPh 2 )( μ -C 4 Ph 4 )(CO) 6 ( 12 ). In 5 , 8a and 8b , one of the ester CO groups is bonded to an Ru atom also coordinated to phosphorus. Figure options Figure options Download full-size image Download as PowerPoint slide

Cluster chemistry: LXX. Preparation and X-ray structure of Ru3{μ3-C3(CO2Me)2}(]μ-CO)(CO)7(PMe2Ph)2

Abstract The title complex has been obtained from a reaction between Ru 3 (CO) 10 (PMe 2 Ph) 2 and C 2 (CO 2 Me) 2 . The alkyne is attached to the closed triangular Ru 3 cluster in the usual μ 3 -η 2 -|mode, the two Ru atoms to which the alkyne is σ-bonded also bearing the PMe 2 Ph ligands, and being bridged by a CO group. A minor product also isolated from this reaction was partially characterised as Ru 3 {C 2 (CO 2 Me) 2 } 3 (CO) 6 -(PMe 2 Ph) 2 .

Reactions of {Ru3(m-PPh2)(CO)9}2(m3:m3-C4) with H+/H- or H2 to Yield Penta- and Hexa-Nuclear Cluster Compounds

Addition of K[BHBus3] to {Ru3(µ-PPh2)(CO)9}2(µ3:µ3-C4) (1), followed by acidification, is proposed to give {Ru3H(µ-PPh2)(CO)9}2(µ3:µ3-C=CHCH=C) (2), in which hydrogen atoms have added to each cluster unit and to the C4 fragment of (1) to give a bis(vinylidene) ligand. The osmium analogue has also been prepared. In contrast, the reaction with dihydrogen results in the pentanuclear complex Ru3{µ3:µ-C2C2[Ru2(µ-PPh2)(CO)6]}(µ- PPh2)(CO)9 (3), by cleavage of an Ru(CO)3 fragment from (1).

Some Au3Ru3 clusters. X-ray structures of Ru3(μ3-CMeCHCMe)(CO)8{Au3(PPh3)3} and Ru3(μ3-C2Ph)(CO)8{Au3(PPh3)3}

Several clusters containing Au 3 Ru 3 cores have been made from reactions between hydrido-triruthenium clusters or AuRu 3 clusters and [0{Au(PPh 3 )} 3 ][BF 4 ]. In the former case, the Au 3 (PPh 3 ) 3 group acts as a three-electron donor, replacing (H + COX The molecular structures of Ru 3 ( μ 3 CMeCHCMe)(CO) 8 {Au 3 (PPh 3 ) 3 } ( 4 ) and Ru 3 ( μ 3 C 2 Ph(CO) 8 {Au 3 (PPh 3 ) 3 } ( 13 ) have been determined by X-ray crystallography. Comparisons are made between the parent Ru3 clusters and their aurated derivatives, which may contain open (bent) or closed triangular Au 3 P 3 moieties, according to whether there is more or less electron density on the cluster.