132154-04-2

Basic information

• Product Name: Mn₂(CO)6(C₃H₇NCHCHNC₃H₇)2
• CAS NO: 132154-04-2
• Molecular Weight: 558.395
• Mol File: 132154-04-2.mol

Chemical Properties

• CAS DataBase Reference: Mn₂(CO)6(C₃H₇NCHCHNC₃H₇)2(CAS DataBase Reference)
• NIST Chemistry Reference: Mn₂(CO)6(C₃H₇NCHCHNC₃H₇)2(132154-04-2)
• EPA Substance Registry System: Mn₂(CO)6(C₃H₇NCHCHNC₃H₇)2(132154-04-2)

Safety Data

• Hazardous Substances Data: 132154-04-2(Hazardous Substances Data)

Upstream product

• 71603-98-0 (CO)5MnMn(CO)3(i-Pr-DAB) 
• 96-47-9 2-methyltetrahydrofuran 
• 71603-98-0 (Mn(CO)5)(Mn(CO)3((CH₃)2CHNCHCHNCH(CH₃)2)) 

Relevant articles and documents

SPECTROSCOPIC STUDIES OF (M,M'= Mn, Re) AND THEIR PHOTOLYSIS PRODUCTS

Photolysis of (M, M' = 1,4-diazabuta-1,3-diene, RN=CH-CH=NR) in 2 -Me-THF leads to both homolytic and heterolytic splitting of the metal-metal bond depending on the solution temperature.In a rigid medium such as a CH4-matrix no breaking on the metal-metal bond is observed but instead formation of in which compound the dab-ligand is ?, ?, ?, ? bridging between M and M'.

Metal to ligand charge-transfer photochemistry of metal-metal-bonded complexes. 8. Photochemistry of (CO)5MnMn(CO)3(α-diimine) complexes. Coupling reactions of the radicals formed and X-ray structure of the photoproduct (CO)4Mn(σ-N,σ-N′,η 2-CN-iPr-pyca)Mn(CO)3

This article describes the photochemistry between 133 and 298 K of five metal-metal-bonded carbonyls (CO)5MnMn(CO)3(α-diimine) (1a-e) (α-diimine = 4,4′-dimethyl-2,2′-bipyridine (bpy′ (1a)), pyridine-2-carbaldehyde N-isopropylimine (iPr-pyca (1b)), 1,4-diisopropyl-1,4-diaza-1,3-butadiene (iPr-DAB (1c)), 1,4-di-p-tolyl-1,4-diaza-1,3-butadiene (pTol-DAB (1d)), 1,4-di-p-anisyl-1,4-diaza-1,3-butadiene (pAn-DAB (1e))) by irradiation into their metal to α-diimine charge-transfer (MLCT) band. At room temperature these complexes undergo homolysis of the metal-metal bond and the radicals formed dimerize to give Mn2(CO)10 and Mn2(CO)6(α-diimine)2 (2a-e). Of these dimers, 2d,e were thermally unstable at room temperature. They decomposed into their radicals, which were characterized with ESR in the case of 2d. Complexes 1b-e showed a side reaction at room temperature, giving rise to the formation of (CO)4Mn(σ-N,σ-N′,η 2-CN-iPr-pyca)Mn(CO)3 (3b) and (CO)3Mn(σ-N,σ-N′,η2-CN,η 2-C′N′-R-DAB) (4c-e), respectively. The crystal structure of 3b was determined, and the data are as follows: monoclinic, P21/a, with a = 15.425 (1) A?, b = 9.867 (1) A?, c = 12.988 (1) A?, β = 111.310 (9)°, and Z = 4; R = 0.041. Both Mn atoms possess a distorted octahedral geometry, and the Mn-Mn distance is shorter than that in Mn2(CO)10. The formation of these complexes 3b, 4c-e was quenched by radical scavengers and favored in viscous solvents such as paraffin. At lower temperatures, the quantum yields for the photoproduction of 2-4 decreased, and in the case of 1c, a novel complex, 5c, was formed at T ? 180 K by reaction of the Mn(CO)3(iPr-DAB) radicals. 5c was identified as Mn2(CO)4(σ-N,σ-N′,η 2-CN-iPr-DAB)2. Raising the temperature above 180 K caused a thermal conversion of 5c into Mn2(CO) 5(σ-N,σ-N′-iPr-DAB)(σ-N,σ-N′, η2-CN-iPr-DAB) (6c). A further increase of temperature above 200 K caused the formation of 2c out of 6c. At temperatures below 183 K, homolysis products were no longer formed, but instead the CO-loss complexes (CO)4Mn(μ-CO)Mn(CO)2(α-diimine) (7) were produced. The thermal and photochemical reactions of the CO-bridged complex 7a were studied. For both primary photoprocesses, homolysis and release of CO, the quantum yields were high and wavelength independent throughout the MLCT band. They are therefore proposed to occur from the same 3σbσ* state of the complex after intersystem crossing/internal conversion from the MLCT state(s). The relative quantum yields of homolysis and CO-loss reactions resemble the ones that were derived for Mn2(CO)10, which points to a similar mechanism for the photochemistry of both types of complexes.

Photochemistry of metal-metal-bonded complexes. 1. MLCT photolysis of (CO)5MM′(CO)3(α-diimine) (M, M′ = Mn, Re) in 2-MeTHF between 133 and 230 K

The photolysis in 2-MeTHF is reported for several complexes (CO)5MM′(CO)3(α-diimine) (M, M′ = Mn, Re) at temperatures varying from 133 to 230 K. Above 200 K homolysis of the metal-metal bond occurs for the complexes with M = Mn and M′ = Mn, Re. At temperatures below 200 K the main reaction products are [M(CO)5]- and [M′(CO)3(α-diimine)(2-MeTHF)]+ if M = Mn, Re and M′ = Mn. Although these 2-MeTHF-coordinated cations reacted back with [M(CO)5]- to the parent compound upon raising the temperature, several P(n-Bu)3-substituted complexes [M(CO)5]-[M′(CO) 3(α-diimine)(P(n-Bu)3)]+ could be isolated. It appeared that the ions were not formed by direct heterolysis of the metal-metal bond but instead by thermal disproportionation of a photosubstituted product (CO)5MM′(CO)2(α-diimine)(2-Me-THF). Several P(n-Bu)3-substituted complexes (CO)5MM′(CO)2(α-diimine)(P(n-Bu)3) could be identified for M = Re, M′ = Mn. Contrary to the complexes with M = Mn, Re and M′ = Mn, the corresponding (CO)5MnRe(CO)3(α-diimine) ones did not show photosubstitution of CO but instead breaking of a metal-nitrogen bond upon photolysis at 133 K. It is proposed that this bond breaking is the primary photoprocess at lower temperatures and that it is followed by release of CO in the case of M′ = Mn. An energy vs. distortion diagram is presented according to which the homolytic splitting of the metal-metal bond and the breaking of the metal-nitrogen bond occur from two different close-lying excited states, 3σbπ* and 3dππ*, respectively.