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5. Syntheses, structures, and reactivity of diruthenium phosphine carbonyl complexes of nitrites and nitrates

Author

Shiu, Kom-Bei, Yang, Luh-Tin, Jean, Shih-Wei, Li, Chien-Hsing, Wu, Ru-Rong, Wang, Ju-Chun, Liou, Lin-Shu, and Chiang, Michael Y.

Subjects
Nitrites -- Research, Nitrates -- Research, Carbonyl compounds -- Research, Ruthenium -- Research, Chemistry
Abstract

The reaction between the cationic (Ru2(CO)4(NCMe)4L2)(BF4)2 where L = PPh3, PPH2(allyl), PPh2Me, PMe3 and excess NaNO2 or NaNO3 in MeOH affords diruthenium phosphine carbonyl complexes of the form (Ru2(CO)4(mu-NO2)2L2) and (Ru2(CO)4(mu-NO3)2L2) without producing oxygen-transfer products. It proceeds via the replacement of the weakly-coordinated equatorial MeCN ligands of the cation by nitrite and nitrate anions. The (Ru2(CO)4(mu-NO2)2L2) complexes exist in two isomeric forms while the (Ru2(CO)4(mu-NO3)2L2) complexes exist as a single isomer only.

Published
1996

6. Synthesis, structure, reactivity, and solution behavior of bis(dicarbonyl(hydridotris(1,2,4-triazolyl)borato)ruthenium(I))(Ru-Ru)

Author

Shiu, Kom-Bei, Guo, Wei-Ning, Peng, Shie-Ming, and Cheng, Ming-Chu

Subjects
Ruthenium -- Research, Potassium compounds -- Research, Coordination compounds -- Analysis, Chemistry
Abstract

Catena-(Ru(O(2)CMe)(CO)(2)) reacts with K(super +)HhB(tz)(3)(super -) to produce bis(dicarbonyl(hydridotris(1,2, 4-triazolyl)borato)ruthenium (I))complex. Crystal structure of this dimer shows that Ru-Ru bond length in this complex is shorter than that in its pyrazolyl analogue. NMR spectrum reveals its fluxional nature in solution. Cyclic voltammetry is used to analyze the redox properties of the compound.

Published
1994

16. Steric effects of bulky diazolylmethane ligands (N-N) on syntheses and structures of [Mo(N-N)(CO)4]

Author

Wang Sue-Lein, Shiu Kom-Bei, Liao Fen-Ling, Chou Chang-Chuan, Peng Shie-Ming, Lin Sheng-Ting, and Cheng Ming-Chu

Subjects
Steric effects, Stereochemistry, Ligand, Organic Chemistry, Substituent, Crystal structure, Biochemistry, Inorganic Chemistry, chemistry.chemical_compound, chemistry, X-ray crystallography, Materials Chemistry, Orthorhombic crystal system, Piperidine, Physical and Theoretical Chemistry, Monoclinic crystal system
Abstract

The N-N ligands of PhHC(3,5-Me 2 Pz) 2 , H 2 C(3,5-Me 2 ;4-BzPz) 2 , H 2 C(3- t BuPz) 2 and H 2 C(3(5)-PhPz) 2 wsere prepared readily from PhHCCl 2 or CH 2 Cl 2 by the same procedure as for H 2 C(3,5-Me 2 Pz) 2 (Pz = pyrazol-1-yl). Subsequent reactions with either [Mo(pip) 2 (CO) 4 ] (pip = piperidine) or [Mo(CO) 6 ], however, gave only [MoPhHC(3,5-Me 2 Pz) 2 (CO) 4 ] ( 1 ), [MoH 2 C(3-PhPz)(5-PhPz)(CO) 4 ] ( 2 ) and [MoH 2 C(3,5-Me 2 ;4-BzPz) 2 (CO) 4 ] ( 3 ). The structural characteristics of 1–3 , [WH 2 C(3,4,5-Me 3 Pz) 2 (CO) 4 ], [WH 2 C(3,5-Me 2 Pz) 2 (CO) 4 ] and [MoH 2 C(3,5-Me 2 Pz) 2 (CO) 4 ], reported previously, suggest firstly that the presence of a bulky substituent such as a phenyl or tert-butyl group at the pyrazolyl skeleton may afford strong nonbonded interaction in [MO(N-N)(CO) 4 ] and inhibit the formation of the stable complexes, [MoH 2 C(3- t BuPz) 2 (CO) 4 ] or [Mo(H 2 C(3-PhPz) 2 (CO) 4 ] and secondly, that the phenyl substituent at the carbon end of the six-membered boat metallacyle, formed by the N-N ligand and the central metal atom, is cis to the most distorted carbonyl in 1 . This explains the facile formation of the η 2 -arene compound, [MoPhHC(3,5-Me 2 Pz) 2 (CO) 3 ] as well as the regiospecific formation of [MoPhHC(3,5-Me 2 Pz) 2 (CO) 2 (η 3 -allyl)(Br)]. 1 , monoclinic, P 2 1 / n , a = 9.718(2), b = 14.198(4), c = 16.076(4) A, β = 96.62(2), Z = 4, R = 0.034, R w = 0.037, based on 2538 reflections with I ⪢ 3σ( I ); 2 , monoclinic, P 2 1 / n , a = 18.093(12), b = 13.138(4), c = 18.745(6) A, β = 98.79(6), Z = 8, R = 0.040, R w = 0.031, based on 4465 reflections with I ⪢ 2σ( I ); and 3 , orthorhombic, Pbca , a = 12.2387(18), b = 22.525(4), c = 20.028(5) A, Z = 8, R = 0.035, R w = 0.032, based on 2095 reflections with I ⪢ 2σ( I ).

Published
1994

17. Synthesis and structural characterization of two molybdenum carbonyl complexes containing dithiocarbamato ligands derived from pyrrolidine and piperidine

Author

Liao Fen-Ling, Shiu Kom-Bei, Wang Sue-Lein, Peng Shie-Ming, and Cheng Ming-Chu

Subjects
Chemistry, Stereochemistry, Ligand, Organic Chemistry, Iminium, Metal carbonyl, Crystal structure, Biochemistry, Medicinal chemistry, Pyrrolidine, Inorganic Chemistry, chemistry.chemical_compound, Materials Chemistry, Piperidine, Physical and Theoretical Chemistry, Triphenylphosphine, Monoclinic crystal system
Abstract

Reaction of [MO(pip) 2 (CO) 4 ] (pip=piperidine) with (S, S) − in acetonitrile gives readily [Moη 2 -(S, S)(CO) 4 ] − , isolated as [PPN][Mo(η 2 -(S, S))(CO) 4 ] (PPN + = bis(triphenylphosphine)iminium; (S, S) − = pyrrolidine- ( 1 ) or piperidine-1-carbodithioato ( 2 )). The two compounds have been characterized by elemental analysis, IR, nuclear magnetic resonance and X-ray crystallography. 1 : monoclinic, P 2 1 / n ; a = 16.207(5), b = 12.804(3) A, c = 20.398(4) A; β = 91.02(2)°; V = 4232(2) A 3 , Z = 4; R = 0.034, R w = 0.037 based on 4989 reflections with I > 3.0σ( I ). 2 : monoclinic, P 2 1 / n ; a = 14.148(4) A, b = 13.646(5) A, c = 22.535(8) A; β = 95.92(3)°; V = 4327(3) A 3 , Z = 4; R = 0.054, R w = 0.041 based on 2048 reflections with I > 2.0σ( I ). No appreciably modified ligand structure is found in response to the different p K a of the amine used to form the specific (S, S) − in the compounds. This feature is rationalized by the electron-withdrawing effect of the metal carbonyl fragment, leading to the observed similarity in both the CO stretching and the MoCO distances.

Published
1993

18. Coordination characteristics of three N,N′-di(azol-1-yl)methanes; substituent effects on infrared absorption and structure of the Group VI metal carbonyl derivatives

Author

Lee Gene-Hsiang, Wang Yu, Shiu Kom-Bei, Liou Kuen-Song, and Cheng Ming-Chu

Subjects
Ligand, Stereochemistry, Organic Chemistry, Cyclohexane conformation, Substituent, Infrared spectroscopy, Metal carbonyl, Triclinic crystal system, Biochemistry, Medicinal chemistry, Inorganic Chemistry, chemistry.chemical_compound, chemistry, Materials Chemistry, Physical and Theoretical Chemistry, Methylene, Tetrahydrofuran
Abstract

Compounds [M(H2CAz2)(CO)4] (M  Cr, Mo, or W), were obtained readily and similarly by refluxing the equivalent amounts of N,N′-di(azol-1-yl)methanes, H2CAz2 (Az = pyrazol-1-yl (Pz), 3,5-dimethylpyrazol-1-yl (Pz′) or 3,4,5-trimethylpyrazol-1-yl (Pz″) with [M(CO)6] (M  Cr, Mo, or W) in a mixed solvent system of 1,2-dimethoxyethane and tetrahydrofuran. Under phase transfer catalysis conditions this gives rise to the new nitrogen-bidentate ligand, H2CPz2″, by reaction of HPz″ with methylene chloride. IR absorption bands in the carbonyl region indicate that no regular trends can be found for different substituents on the pyrazolyl ring. This irregularity is attributed to flexibility of the boat conformation formed from the metal centre and the ligand, which is supported by comparative structure details of [Mo(H2CPz2′)(CO)4], reported previously, [W(H2CPz2″)(CO)4] (6) and [W(H2CPz2′)(CO)4] (7): 6, triclinic, P1, a = 8.403(3), b = 9.589(3), c = 13.310(3) A, α = 94.476(22), β = 102.837(21), γ = 110.355 (25)°, Z = 2, R = 0.024, Rw = 0.023, based on 3070 with I > 2σ (I). 7, monoclinic, P21/c, a = 9.178(3), b = 15.885(9), c = 12.394(10) A, β = 108.64(9)°, Z = 4, R = 0.030, Rw = 0.030, based on 2625 reflections with I > 2.5σ(I).

Published
1993

20. Linking Tribridged Dicopper Complexes with Neutral Dipyridyl Compounds to Coordination Oligomers and Polymers.

Author

Shiu, Ler ‐ Chun, Chuang, Jen ‐ Han, Wu, Tian ‐ Shung, and Shiu, Kom ‐ Bei

Subjects
COPPER compounds, BIPYRIDINE, COORDINATION polymers, OLIGOMERS, PHOSPHINES, SUPRAMOLECULAR chemistry
Abstract

The stable tribridged dicopper(I) carboxylate complexes [Cu2(μ-dppm)2(μ-O2CR)]BF4 (RCO2 - = formate (OFc-), m1; acetate (OAc-), m2; benzoate (OBAc-), m3; o-toluate (O2TAc-), m4; p-toluate (O4TAc-), m5; 4-phenylbutyrate (O4PBAc-), m6; 2-nitrobenzoate (O2NBAc-), m7), abbreviated as MM, and neutral dipyridyl compounds (NN; NN = 4,4'-bipyridine (bpy), 1,2-bis(4-pyridyl)ethane (bpa), trans-1,2-bis(4-pyridyl)ethylene (bpe), 4,4'-trimethylenedipyridine (tmp)) can form dynamic equilibria in CH2Cl2. From the equilibrium mixtures containing MM and NN with MM/NN = 1:1, nine 2:1 oligomers ([(m1)2(μ-bpy)](BF4)2 (o1a(BF4)2), [(m3)2(μ-bpe)](BF4)2 (o3c(BF4)2), [(m3)2(μ-tmp)](BF4)2 (o3d(BF4)2), [(m4)2(μ-bpe)](BF4)2 (o4c(BF4)2), [(m5)2(μ-bpy)](BF4)2 (o5a(BF4)2), [(m5)2(μ-tmp)](BF4)2 (o5d(BF4)2), [(m6)2(μ-bpa)](BF4)2 (o6b(BF4)2), [(m7)2(μ-bpy)](BF4)2 (o7a(BF4)2), [(m7)2(μ-bpa)](BF4)2 (o7b(BF4)2)), one 2:3 oligomer ([{(m2)(bpy)}2(μ-bpy)](BF4)2 (o2a(BF4)2)), and five 1:1 polymers ([(m2)(μ-bpe)] n (BF4) n (p2c(BF4) n) , [(m2)(μ-tmp)] n (BF4) n (p2d(BF4) n) , [(m3)(μ-bpy)] n (BF4) n (p3a(BF4) n) , [(m3)(μ-tmp)] n (BF4) n (p3d(BF4) n) , [(m7)(μ-tmp)] n (BF4) n (p7d(BF4) n)) were obtained as single crystals, and their structures were determined by X-ray crystallography. Both experimental and theoretical results support the presence of two oligomeric species, [{Cu2(μ-dppm)2(μ-O2CR)}2(μ-NN)]2+ and [{Cu2(μ-dppm)2(μ-O2CR)(NN)}2(μ-NN)]2+), in dynamic equilibrium. The oligomers (such as o3d(BF4)2) can serve as seeds to induce the formation of soluble coordination polymers as crystals (such as p3d(BF4)n). [ABSTRACT FROM AUTHOR]

Published
2017
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22. Synthesis and Structures of d10–d10M2(µ-dppm)2Complexes with Sensitive Metal–Metal Distances in Response to the Binding of Sigma Donors

Author

Shiu, Ler-Chun, Liu, Shih-An, Wu, Tian-Shung, and Shiu, Kom-Bei

Abstract

Diphosphine-bridged dicopper(I) acetate complexes [Cu2(µ-dppm)2(µ-OAc)]X (2X; X-= BF4-, PF6-) and [Cu2(µ-dppm)2(µ-OAc)(MeCN)]X (4X) were prepared and the structures of 2(PF6) and 4(PF6) determined by X-ray crystallography. The ground-state geometries of [Cu2(µ-dppm)2(µ-OAc)]+and [Cu2(µ-dppm)2(µ-OAc)(L)]+(L = py, MeCN, THF, acetone, MeOH) were also obtained using density functional theory (DFT). The increased Cu–Cu distances found experimentally and theoretically by comparing the structures of cation [Cu2(µ-dppm)2(µ-OAc)]+and its derivatives [Cu2(µ-dppm)2(µ-OAc)(L)]+reflect the binding of various sigma donors (L). When using [Cu2(µ-dppm)2(µ-OAc)]+as a structure sensor, the electron-donating strength of a sigma donor can be quantitatively expressed as a DFT-calculated Cu–Cu distance with the relative strength in the order py > MeCN> THF> acetone > MeOH, as determined. The increased Cu–Cu distances in [Cu2(µ-dppm)2(µ-OAc)(L)]+, relative to that in [Cu2(µ-dppm)2(µ-OAc)]+, are found to be sensitive to the binding of sigma donors (L). When using [Cu2(µ-dppm)2(µ-OAc)]+as a structure sensor, the electron-donating strength of a sigma donor can be quantitatively expressed as a DFT-calculated Cu–Cu distance with the relative strength of py > MeCN> THF> acetone > MeOH.

Published
2016
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