Synthesis and Molecular Structure of Six-Coordinate Dichlorodihydridoruthenium(IV) and Five-Coordinate Vinylideneruthenium(II) Complexes

Abstract

The dichlorodihydridoruthenium(IV) compound [RuH2Cl2(PiPr3)2] (4) was prepared from [RuCl2(C8H12)]n (3), PiPr3, and H2 in 2‐butanol via the chlorohydridoruthenium(II) derivative [RuHCl(H2)(PiPr3)2] (5) as an intermediate. The synthesis of 5 was achieved under similar conditions from 3, PiPr3, H2, and 2‐butanol in the presence of NEt3. Compound 4, which was characterized by X‐ray crystal structure analysis, reacts with excess phenylacetylene to give the phenylvinylidene complex [RuCl2(=C=CHPh)(PiPr3)2] (7) and with propargylic alcohols or derivatives thereof to afford the vinylcarbene complexes [RuCl2(=CHCH=CR2)(PiPr3)2] (9, 10), respectively. From 5 and terminal alkynes RC≡CH the chlorohydridovinylidene compounds [RuHCl(=C=CHR)(PiPr3)2] (11, 12) were obtained. The phenylvinylidene complex [RuCl2(=C=CHPh)(PCy3)2] (15) was prepared from phenylacetylene and either [RuH2Cl2(PCy3)2] (14) or one of the carbene deriva‐tives [RuCl2(=CHR)(PCy3)2] (16, 17) as starting materials. The X‐ray crystal structure analysis of 15 confirms a distorted square‐pyramidal geometry with the vinylidene ligand in the apical position. The interconversion of 4 to 5 and of the tricyclohexylphosphane counterparts 14 to 13 was achieved by hydrogen transfer from 2‐propanol in the presence of PR3. The reverse reaction occurs upon treatment of 5 or 13 with the corresponding phosphonium salt [HPR3]Cl or HCl, respectively.

The Sensitive Balance between Five-Coordinate Carbene and Six-Coordinate Carbyne Ruthenium Complexes Formed from Ruthenium Vinylidene Precursors

“…350 for 3a − j and at δ ca. 360 for 4a − c , which is in good agreement with the chemical shifts observed for other mononuclear vinylideneruthenium complexes. , …”

“…In contrast to the Cl−Ru−O1 axis, which is almost linear, the P1−Ru−P2 axis is significantly bent, both phosphorus atoms pointing away from the Ru−C1 unit. An analogous square-pyramidal configuration has been found for the carbeneruthenium complexes [RuCl 2 (CHCH 2 Ph)(P i Pr 3 ) 2 ] and [RuCl 2 (CHR)(PCy 3 ) 2 ] (R = 4-C 6 H 4 Cl, CHCPh 2 ) as well as for the related vinylidene derivatives [RuCl 2 (CCHPh)L 2 ] (L = P i Pr 3 , PCy 3 ) . Compared with [RuCl 2 (CHCH 2 Ph)(P i Pr 3 ) 2 ] and [RuCl 2 (CHR)(PCy 3 ) 2 ], the bond length Ru−C1 in 6a is rather short, whereas the distance C1−O2 is ca.…”

“…The axes P1−Ru1−P2 and Cl1−Ru1−Cl2 are significantly bent and pointing away from the Ru1−C1 unit. The coordination geometry is nearly identical to that of the parent vinylidene complex 1b , the only noticeable difference being the more pronounced bending of the P1−Ru1−P2 axis in 2b than in 1b [169.17(3)°] 7a. The most remarkable feature of the structure, however, is the distance Ru1−C1 [ca.…”

The Sensitive Balance between Five-Coordinate Carbene and Six-Coordinate Carbyne Ruthenium Complexes Formed from Ruthenium Vinylidene Precursors

“…350 for 3a − j and at δ ca. 360 for 4a − c , which is in good agreement with the chemical shifts observed for other mononuclear vinylideneruthenium complexes. , …”

“…In contrast to the Cl−Ru−O1 axis, which is almost linear, the P1−Ru−P2 axis is significantly bent, both phosphorus atoms pointing away from the Ru−C1 unit. An analogous square-pyramidal configuration has been found for the carbeneruthenium complexes [RuCl 2 (CHCH 2 Ph)(P i Pr 3 ) 2 ] and [RuCl 2 (CHR)(PCy 3 ) 2 ] (R = 4-C 6 H 4 Cl, CHCPh 2 ) as well as for the related vinylidene derivatives [RuCl 2 (CCHPh)L 2 ] (L = P i Pr 3 , PCy 3 ) . Compared with [RuCl 2 (CHCH 2 Ph)(P i Pr 3 ) 2 ] and [RuCl 2 (CHR)(PCy 3 ) 2 ], the bond length Ru−C1 in 6a is rather short, whereas the distance C1−O2 is ca.…”

“…The axes P1−Ru1−P2 and Cl1−Ru1−Cl2 are significantly bent and pointing away from the Ru1−C1 unit. The coordination geometry is nearly identical to that of the parent vinylidene complex 1b , the only noticeable difference being the more pronounced bending of the P1−Ru1−P2 axis in 2b than in 1b [169.17(3)°] 7a. The most remarkable feature of the structure, however, is the distance Ru1−C1 [ca.…”

New d 4 dihydrides of Ru( iv ) and Os( iv ) with π-donor ligands: M(H) 2 (chelate)(P i Pr 3 ) 2 with chelate = ortho-XYC 6

“…The hydride ligands appear as a sharp triplet (intensity 2H integrated vs. aryl ortho H), the aryl region shows only two chemical shifts (AA 0 XX 0 pattern), and the i Pr methyls appear as a doublet of doublets; the implied lack of virtual coupling in the latter suggests that the phosphines are not trans (i.e., 2 J PP 0 is not large). The 31 P NMR spectrum is a singlet near 91 ppm, which compares well to the value 19 103.2 ppm in Ru(H) 2 Cl 2 (P i Pr 3 ) 2 . 20 The presence of equimolar added catechol detectably alters the spectral parameters of Ru(H) 2 (OC 6 H 4 O)L 2 in benzene at 20 1C.…”

Hydrogenolysis of a Ruthenium Carbene Complex to Yield Dihydride−Dihydrogen Tautomers: Mechanistic Implications for Tandem ROMP−Hydrogenation Catalysis

“…Hydrogenolysis in nonchlorinated solvents, in the presence or absence of base (DMA; PS-DMA; DMA = dimethylacetamide, PS = Proton Sponge, 1,8-bis(dimethylamino)naphthalene), reveals a dihydrogen complex, either alone or accompanying 2 . By analogy with related work, hydridochloro complex 3 2b was expected. Heterolytic activation of dihydrogen is well known to give such species.…”

The Sensitive Balance between Five-Coordinate Carbene and Six-Coordinate Carbyne Ruthenium Complexes Formed from Ruthenium Vinylidene Precursors

“…350 for 3a − j and at δ ca. 360 for 4a − c , which is in good agreement with the chemical shifts observed for other mononuclear vinylideneruthenium complexes. , …”

“…In contrast to the Cl−Ru−O1 axis, which is almost linear, the P1−Ru−P2 axis is significantly bent, both phosphorus atoms pointing away from the Ru−C1 unit. An analogous square-pyramidal configuration has been found for the carbeneruthenium complexes [RuCl 2 (CHCH 2 Ph)(P i Pr 3 ) 2 ] and [RuCl 2 (CHR)(PCy 3 ) 2 ] (R = 4-C 6 H 4 Cl, CHCPh 2 ) as well as for the related vinylidene derivatives [RuCl 2 (CCHPh)L 2 ] (L = P i Pr 3 , PCy 3 ) . Compared with [RuCl 2 (CHCH 2 Ph)(P i Pr 3 ) 2 ] and [RuCl 2 (CHR)(PCy 3 ) 2 ], the bond length Ru−C1 in 6a is rather short, whereas the distance C1−O2 is ca.…”

“…The axes P1−Ru1−P2 and Cl1−Ru1−Cl2 are significantly bent and pointing away from the Ru1−C1 unit. The coordination geometry is nearly identical to that of the parent vinylidene complex 1b , the only noticeable difference being the more pronounced bending of the P1−Ru1−P2 axis in 2b than in 1b [169.17(3)°] 7a. The most remarkable feature of the structure, however, is the distance Ru1−C1 [ca.…”

New d 4 dihydrides of Ru( iv ) and Os( iv ) with π-donor ligands: M(H) 2 (chelate)(P i Pr 3 ) 2 with chelate = ortho-XYC 6

“…The hydride ligands appear as a sharp triplet (intensity 2H integrated vs. aryl ortho H), the aryl region shows only two chemical shifts (AA 0 XX 0 pattern), and the i Pr methyls appear as a doublet of doublets; the implied lack of virtual coupling in the latter suggests that the phosphines are not trans (i.e., 2 J PP 0 is not large). The 31 P NMR spectrum is a singlet near 91 ppm, which compares well to the value 19 103.2 ppm in Ru(H) 2 Cl 2 (P i Pr 3 ) 2 . 20 The presence of equimolar added catechol detectably alters the spectral parameters of Ru(H) 2 (OC 6 H 4 O)L 2 in benzene at 20 1C.…”

Hydrogenolysis of a Ruthenium Carbene Complex to Yield Dihydride−Dihydrogen Tautomers: Mechanistic Implications for Tandem ROMP−Hydrogenation Catalysis

“…Hydrogenolysis in nonchlorinated solvents, in the presence or absence of base (DMA; PS-DMA; DMA = dimethylacetamide, PS = Proton Sponge, 1,8-bis(dimethylamino)naphthalene), reveals a dihydrogen complex, either alone or accompanying 2 . By analogy with related work, hydridochloro complex 3 2b was expected. Heterolytic activation of dihydrogen is well known to give such species.…”

The Sensitive Balance between Five-Coordinate Carbene and Six-Coordinate Carbyne Ruthenium Complexes Formed from Ruthenium Vinylidene Precursors

“…350 for 3a − j and at δ ca. 360 for 4a − c , which is in good agreement with the chemical shifts observed for other mononuclear vinylideneruthenium complexes. , …”

“…In contrast to the Cl−Ru−O1 axis, which is almost linear, the P1−Ru−P2 axis is significantly bent, both phosphorus atoms pointing away from the Ru−C1 unit. An analogous square-pyramidal configuration has been found for the carbeneruthenium complexes [RuCl 2 (CHCH 2 Ph)(P i Pr 3 ) 2 ] and [RuCl 2 (CHR)(PCy 3 ) 2 ] (R = 4-C 6 H 4 Cl, CHCPh 2 ) as well as for the related vinylidene derivatives [RuCl 2 (CCHPh)L 2 ] (L = P i Pr 3 , PCy 3 ) . Compared with [RuCl 2 (CHCH 2 Ph)(P i Pr 3 ) 2 ] and [RuCl 2 (CHR)(PCy 3 ) 2 ], the bond length Ru−C1 in 6a is rather short, whereas the distance C1−O2 is ca.…”

“…The axes P1−Ru1−P2 and Cl1−Ru1−Cl2 are significantly bent and pointing away from the Ru1−C1 unit. The coordination geometry is nearly identical to that of the parent vinylidene complex 1b , the only noticeable difference being the more pronounced bending of the P1−Ru1−P2 axis in 2b than in 1b [169.17(3)°] 7a. The most remarkable feature of the structure, however, is the distance Ru1−C1 [ca.…”

New d 4 dihydrides of Ru( iv ) and Os( iv ) with π-donor ligands: M(H) 2 (chelate)(P i Pr 3 ) 2 with chelate = ortho-XYC 6

“…The hydride ligands appear as a sharp triplet (intensity 2H integrated vs. aryl ortho H), the aryl region shows only two chemical shifts (AA 0 XX 0 pattern), and the i Pr methyls appear as a doublet of doublets; the implied lack of virtual coupling in the latter suggests that the phosphines are not trans (i.e., 2 J PP 0 is not large). The 31 P NMR spectrum is a singlet near 91 ppm, which compares well to the value 19 103.2 ppm in Ru(H) 2 Cl 2 (P i Pr 3 ) 2 . 20 The presence of equimolar added catechol detectably alters the spectral parameters of Ru(H) 2 (OC 6 H 4 O)L 2 in benzene at 20 1C.…”

Hydrogenolysis of a Ruthenium Carbene Complex to Yield Dihydride−Dihydrogen Tautomers: Mechanistic Implications for Tandem ROMP−Hydrogenation Catalysis

“…Hydrogenolysis in nonchlorinated solvents, in the presence or absence of base (DMA; PS-DMA; DMA = dimethylacetamide, PS = Proton Sponge, 1,8-bis(dimethylamino)naphthalene), reveals a dihydrogen complex, either alone or accompanying 2 . By analogy with related work, hydridochloro complex 3 2b was expected. Heterolytic activation of dihydrogen is well known to give such species.…”